White-rimmed Shingle Lichen (Fuscopannaria leucosticta): COSEWIC assessment and status report 2019

Official title: COSEWIC Assessment and Status Report on the White-rimmed Shingle Lichen (Fuscopannaria leucosticta) in Canada 2019

Committee on the status of Endangered Wildlife in Canada (COSEWIC)
Threatened 2019

COSEWIC assessment summary

Assessment summary – May 2019

Common name: White-rimmed Shingle Lichen

Scientific name: Fuscopannaria leucosticta

Status: Threatened

Reason for designation: This rare lichen in Canada grows in wet forests of Nova Scotia, New Brunswick and Ontario, with three known subpopulations. The main threat to the species in Canada is logging of host trees Eastern White Cedar and Red Maple. As with other cyanolichens, this species is sensitive to atmospheric pollution in the form of acid rain and to climate change including more extreme weather events leading to blowdown of host trees. The decline in number of mature individuals observed over the past ten years is expected to continue, with about 45% of the population expected to be lost over the next three generations.

Occurrence: Ontario, Quebec, New Brunswick, Nova Scotia

Status history: Designated threatened in May 2019.

COSEWIC executive summary

White-rimmed Shingle Lichen
Fuscopannaria leucosticta

Wildlife species description and significance

White-rimmed Shingle Lichen, Fuscopannaria leucosticta, is a rare lichen that grows on trees in wet forests of eastern Canada. The lichen consists of many small, overlapping lobes (like shingles). These lobes typically have a dark olive-grey colour on their upper surface, and a noticeable white rim on the edges. Mature colonies produce many brownish-coloured discs (fruiting bodies) on their upper surface.

Distribution

White-rimmed Shingle Lichen has a disjunct global distribution. It occurs primarily in eastern Canada, the southeastern United States, and also in Europe and the Asia-Pacific region. In Canada, it is found in New Brunswick, Nova Scotia, and a small area in western Ontario. In the U.S.A., it has not been detected in any New England states for at least 30 years.

Habitat

The White-rimmed Shingle Lichen lives almost exclusively on the bark of trees in wet forests. It is most commonly found on Red Maple in Nova Scotia, and on Eastern White Cedar in New Brunswick and Ontario. It usually occurs on the uppermost surface of tree trunks that lean away from the vertical position, and it avoids the southwestern sides of trunks. The preferred habitat of this species ranges from open swamps, with persistent standing water throughout the year, to dense riparian (stream or lakeside) corridors or transitional habitats near peatlands.

Biology

Lichens are symbiotic organisms, formed by the association of a fungus and a photosynthetic green alga or cyanobacterium. In the White-rimmed Shingle Lichen, the photosynthetic partner is a cyanobacterium belonging to the genus Nostoc. The fungus is an ascomycete in the family Pannariaceae.

This lichen is thought to disperse over long distances by spores but may colonize nearby patches of tree bark if fragments break off the main body (thallus). Because the spores contain only fungal DNA, a compatible cyanobacterium must already be present if new habitats are to be colonized. The generation time of this species is unknown, but related lichen species require between 5 and 22 years to reach maturity. Available data suggest the generation time is at least 12 years.

Population size and trends

Based on surveys, 1,663 thalli of the White-rimmed Shingle Lichen have been enumerated and found on 502 trees in 88 occurrences, in Canada. Of the known thalli, about 45% are in New Brunswick, about the same percentage are in Nova Scotia, and less than 10% are in Ontario. Based on the information provided by distribution models and developed for this report, the population in Canada is estimated to be approximately 9,265 thalli in total.

Threats and limiting factors

The main threat to White-rimmed Shingle Lichen in Canada is logging of Eastern White Cedar and Red Maple. This species is also sensitive to atmospheric pollution in the form of acid rain. Climate change is also a threat particularly in the form of warmer dryer summers to which this lichen is sensitive as its photosynthetic partner is a cyanobacterium. Hence, it requires liquid water to initiate photosynthesis, unlike lichens associated with green algae that become metabolically active with humid air. Climatic changes not only stress the lichen but may also result in an increase in the incidence of forest fires. Furthermore, the predicted increase in the frequency of extreme weather events is likely to cause blowdown of host trees. Grazing by invasive slugs is another threat but currently it seems to be limited to Nova Scotia. Overall, it is predicted that 45% of the population of White-rimmed Shingle Lichen could be lost over the next three generations (36 years) as a result of threats.

Protection, status, and ranks

White-rimmed Shingle Lichen has a national rank of N2N3 – imperilled to vulnerable and a general status rank of N3 (vulnerable). The Natural Heritage Information Centre (Ontario) ranks the species as S1S2 (critically imperilled to imperilled), and the Atlantic Conservation Data Centre ranks it as S2S3 (imperilled to vulnerable) in New Brunswick and Nova Scotia.

Technical summary

Scientific name: Fuscopannaria leucosticta

English name: White-rimmed Shingle Lichen

French name: Fuscopannaire à taches blanches

Range of occurrence in Canada: Ontario, Quebec, New Brunswick, Nova Scotia

Demographic information

Generation time based on other studied cyanolichen species.

12 years

Is there an [observed, inferred, or projected] continuing decline in number of mature individuals?

Yes, both observed and projected

Estimated percent of continuing decline in total number of mature individuals within [5 years or 2 generations]

36%

[Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over the last [10 years, or 3 generations]

9.3% decline over last ten years

[Projected or suspected] percent [reduction or increase] in total number of mature individuals over the next [10 years, or 3 generations]

45% projected reduction over the next three generations

[Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over any [10 years, or 3 generations] period, over a time period including both the past and the future. 9.3% lost over last ten years plus 36% losses projected over the next 2 generations.

45% reduction

Are the causes of the decline a) clearly reversible and b) understood and c) ceased?

a. no, not in the short-term unless logging is curtailed and climate change is controlled
b. yes
c. no

Are there extreme fluctuations in number of mature individuals?

No

Extent and occupancy information

Estimated extent of occurrence (EOO)

576,652 km²

Index of area of occupancy (IAO) (Always report 2x2 grid value)

344 km²

Is the population “severely fragmented” that is, is >50% of its total area of occupancy in habitat patches that are (a) smaller than would be required to support a viable population, and (b) separated from other habitat patches by a distance larger than the species can be expected to disperse?

a. possibly: 78% of sites have fewer than 15 mature individuals (colonies,) and 49% have fewer than 5.
b. Long-distance dispersal by ascospores is possible but has a very low probability of success.

Number of “locations”^* (use plausible range to reflect uncertainty if appropriate)

>10 to 88

Is there an [observed, inferred, or projected] decline in extent of occurrence?

Yes – Inferred if the small Ontario subpopulation is lost as a result of forestry activities, air pollution or habitat disturbance.

Is there an [observed, inferred, or projected] decline in index of area of occupancy?

Yes – Projected

Is there an [observed, inferred, or projected] decline in number of subpopulations?

Yes – Inferred if the small Ontario subpopulation is lost as a result of forestry activities, air pollution or habitat disturbance.

Is there an [observed, inferred, or projected] decline in number of “locations”*?

Yes – Projected decline

Is there an [observed, inferred, or projected] decline in [area, extent and/or quality] of habitat?

Yes – In all three subpopulations, projected on the basis of forestry activities and climate change.

Are there extreme fluctuations in number of subpopulations?

No

Are there extreme fluctuations in number of “locations”?

No

Are there extreme fluctuations in extent of occurrence?

No

Are there extreme fluctuations in index of area of occupancy?

No

^* See definitions and abbreviations on COSEWIC website and International Union for Conservation of Nature (IUCN) (Feb 2014) for more information on this term.

Quantitative analysis

Probability of extinction in the wild is at least [20% within 20 years or 5 generations, or 10% within 100 years]: Not done

Threats (actual or imminent, to populations or habitats, from highest impact to least)

Was a threats calculator completed for this species? Yes (draft Appendix 1). 27 February 2018.

Major threats include:

1. Logging and wood harvesting
2. Climate change and severe weather
3. Air pollution
4. Invasive and other problematic species (invasive slugs)

What additional limiting factors are relevant? In the long-term, there may also be impacts from shifting bioclimatic envelopes on host trees and further acidification of habitats.

Rescue effect (immigration from outside Canada)

Status of outside population(s)?

The nearest occurrences to the Ontario subpopulation are in Minnesota, Wisconsin, and Michigan, where the species has largely disappeared and not been collected within the last 15 years. The species has also not been found since 1986 in Pennsylvania and since 1953 in Maine.

Is immigration known or possible?

It is possible but unlikely given the distance involved.

Would immigrants be adapted to survive in Canada?

Probably, as long as suitable strains of the cyanobacterium are available for capture by the germinating lichen spores.

Is there sufficient habitat for immigrants in Canada?

Probably if forestry activity and air pollution levels are reduced.

Are conditions deteriorating in Canada?⁺

Yes – Eastern White Cedar and Red Maple swamps are being logged for lumber and biomass. Such old-growth forests are not regenerating rapidly enough to compensate for losses.

Are conditions for the source population deteriorating?⁺

Yes – Collections in northern U.S.A. states are less frequent, suggesting reduced prevalence.

Is the Canadian population considered to be a sink?⁺

Unlikely

Is rescue from outside populations likely?

Unlikely

⁺ See Table 3 (Guidelines for modifying status assessment based on rescue effect).

Data sensitive species

Is this a data sensitive species? No – There is a possibility that owners of private or unprotected forests might wish to proceed with logging if this lichen were known to occur. However, with consultation between government, industry, and the public, knowledge about the presence of this lichen species is more likely to prove beneficial, as a result of increased awareness about endangered organisms.

Status history

COSEWIC: Designated threatened in May 2019.

Status and reasons for designation

Status: Threatened

Alpha-numeric codes: A3c+4c

Reasons for designation: This rare lichen in Canada grows in wet forests of Nova Scotia, New Brunswick and Ontario, with three known subpopulations. The main threat to the species in Canada is logging of host trees Eastern White Cedar and Red Maple. As with other cyanolichens, this species is sensitive to atmospheric pollution in the form of acid rain and to climate change including more extreme weather events leading to blowdown of host trees. The decline in number of mature individuals observed over the past ten years is expected to continue, with about 45% of the population expected to be lost over the next three generations.

Applicability of criteria

Criterion A (Decline in total number of mature individuals): Meets threatened, A3c, as there is a projected future reduction in the total number of mature individuals in the lichen population of 45% over the next three generations (36 years), based on projected loss habitat as a result of logging activities and extreme weather events, as the loss of occupied sites over the past few years is expected to continue at similar rates in the future. Also meets threatened A4c, as the observed reduction in the availability of host trees over the past few years due to forest harvesting is projected to continue into the future over a total period (past and future) of at least three generations (36 years) with an overall population reduction of about 45%.

Criterion B (Small distribution range and decline or fluctuation): Does not meet criteria as the EOO exceeds the limit and there are more than 10 locations.

Criterion C (Small and declining number of mature individuals): May meet threatened, C1 as the total estimated population may be less than 10,000 mature individuals and there is an estimated continuing decline that may exceed 10% of the number of mature individuals over three generations.

Criterion D (Very small or restricted population): Does not meet criteria as the total population exceeds 1000 individuals and the IAO exceeds the threshold.

Criterion E (Quantitative analysis): Not done.

COSEWIC history

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal-Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWIC designated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.

COSEWIC mandate

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens.

COSEWIC membership

COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members and the co-chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status reports on candidate species.

Definitions (2019)

Wildlife species

A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.

Extinct (X)

A wildlife species that no longer exists.

Extirpated (XT)

A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.

Endangered (E)

A wildlife species facing imminent extirpation or extinction.

Threatened (T)

A wildlife species likely to become endangered if limiting factors are not reversed.

Special concern (SC)
(Note: Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990.)

A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.

Not at risk (NAR)
(Note: Formerly described as “Not In Any Category”, or “No Designation Required.”)

A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.

Data deficient (DD)
(Note: Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” [insufficient scientific information on which to base a designation] prior to 1994. Definition of the [DD] category revised in 2006.)

A category that applies when the available information is insufficient (a) to resolve a species’ eligibility for assessment or (b) to permit an assessment of the species’ risk of extinction.

The Canadian Wildlife Service, Environment and Climate Change Canada, provides full administrative and financial support to the COSEWIC Secretariat.

Wildlife species description and significance

Name and classification

Scientific Name: Fuscopannaria leucosticta (Tuck.) P.M. Jørg. (1994)

Synonym: Parmelia leucosticta Tuck. (1853); Pannaria leucosticta (Tuck.) Tuck. ex Nyl. (1859); Pannularia leucosticta (Tuck.) Stizenb. (1887)

Common Name: White-rimmed Shingle Lichen, Fuscopannaire à taches blanches

Family: Pannariaceae

Major Group: Lichens (Lichenized Ascomycetes) Fuscopannaria leucosticta (Tuck.) P.M. Jørg. is a cyanobacterial lichen in the family Pannariaceae.

Morphological description

Fuscopannaria leucosticta has a sub-foliose to squamulose growth form, usually forming irregularly shaped colonies of 1 to 8 cm across. The upper surface (cortex) of the thallus ranges from mineral grey to a rust-brown or even blackish colour but is most often a medium olive-grey. Squamules are usually small, less than 0.5 mm across, but lobes of some thalli can reach up to 2 mm across (Figure 1). Both squamules and larger lobes typically display a distinct white colour along the margins that is formed by closely appressed white hairs called the tomentum. Fuscopannaria leucosticta has a prothallus, consisting of a blue-black fibrous mat of hyphae that underlies the thallus or body of the lichen and extends several millimetres beyond its edges. This prothallus is well-developed in F. leucosticta, up to 0.5 mm thick, or slightly greater than the thallus itself.

The photosynthetic partner in F. leucosticta is a cyanobacterium in the genus Nostoc. This photobiont is also common in many other lichens of the Pannariaceae.

Fruiting bodies (apothecia) in F. leucosticta have a broad brown disc that extends above the surface of the cortex and is surrounded by a thallus-coloured margin consisting of both the fungus and cyanobacterium. These apothecia are 0.5 to 1.5 mm across. When wet, apothecia appear swollen, with the disc often protruding beyond the edges of the exciple and appearing light brown or peach-coloured. When dry, the disc is typically sunken and dark brown or rust-brown. The absence of asexual reproductive structures (for example, soredia) is a diagnostic feature of the species.

The spores of F. leucosticta are colourless, elliptical, 19 to 23 x 9 to 11 μm, and surrounded by a clear gelatinous layer (perispore) that is smooth, 23 to 27 μm long, and usually tapered to a point at both ends (Jørgensen 2000). This is a useful distinction from morphologically similar species. Two similar species can be distinguished by their spores. Protopannaria pezizoides has spores that are slightly larger, and with a perispore that has a warty surface and blunt tips. Pannaria rubiginosa spores have a roughened surface and are often pointed at only one end. However, these spore-based features are only necessary for the identification of atypical specimens.

Chemistry

Fuscopannaria leucosticta can also be distinguished from other species by its chemistry. The interior layer (medulla) of F. leucosticta does not react when spot-tested with PD (para-phenylenediamine), whereas the medulla of Pannaria rubiginosa will usually turn orange (Jørgensen 1978). The asci of F. leucosticta react with a potassium iodide solution; they possess an apical amyloid ring structure, which will turn blue when iodine solutions are added. Neither Protopannaria pezizoides, nor Pannaria rubiginosa have such structures. Nevertheless, while Protopannaria pezizoides shows no reaction with exposure to iodine solutions, in Pannaria rubiginosa both asci and paraphyses will react blue.

Designatable units

There is considerable geographic separation between occurrences in Ontario and those in New Brunswick and Nova Scotia. Fuscopannaria leucosticta colonizes Eastern White Cedar, Thuja occidentalis, in Ontario and New Brunswick, and Red Maple, Acer rubrum, in Nova Scotia. These differences in host associations are likely due to the prevalence of particular host species in the wet forests where the lichen thrives (Haughian et al. 2018), rather than to any incipient ecotypification or population divergence. There appear to be no morphological differences in the samples collected from the three subpopulations. No molecular work has been done on thalli from different areas. Thus, there is no information to warrant more than one designatable unit.

Special significance

Fuscopannaria leucosticta is one of a group of rare cyanolichens that are largely dependent upon Eastern White Cedar or Red Maple swamp forests. This group includes Erioderma mollisimum (endangered; COSEWIC 2009, 2014), Pannaria lurida (threatened; COSEWIC 2016), and Degelia plumbea (special concern; COSEWIC 2010). All of the above species were detected during surveys of high-probability F. leucosticta habitats. Fuscopannaria leucosticta appears to be a valuable indicator of old, undisturbed forests (Haughian et al. 2018), an increasingly rare type of ecosystem in Atlantic Canada (Loo and Ives 2003). Other At risk species, like the Canada Warbler (Wilsonia canadensis; COSEWIC 2008) and the Olive-sided Flycatcher (Nuttallornis borealis; COSEWIC 2007), are also associated with these ecosystems and were detected during the recent surveys.

Distribution

Global range

Fuscopannaria leucosticta is a species of temperate forests with a disjunct distribution, primarily in eastern North America and northern parts of the Asia Pacific region (Jørgensen 1978; Jørgensen and Sipman 2007; GBIF Secretariat 2017). In the eastern United States, it has been reported as an infrequent species on several lichen inventories (Perlmutter 2006; Keller et al. 2007; Lendemer and Tripp 2008) (Figure 2). There appears to be a disjunct western component of the range around Lake Superior. F. leucosticta is uncommon in Africa (Alstrup and Christensen 2006), South America (Jørgensen and Sipman 2007) and Europe (Spribille 2009).

The global distribution pattern of F. leucosticta suggests that it is a Tertiary relict because it is primarily found in places that served as interglacial refuges throughout Europe, Asia, and North America (Jørgensen and Sipman 2007).

Canadian range

In Canada, F. leucosticta is currently limited to New Brunswick and Nova Scotia, with a small cluster of occurrences in western Ontario. There was an early record from Quebec, just north of Montréal in the 1880s, although the exact site could not be verified. The lichen is assumed to no longer be present in this area, as satellite imagery indicates that there is no suitable habitat in the general area. Other surveys in Quebec have, to date, failed to discover F. leucosticta in the province.

The species is considered to consist of three subpopulations in Canada. The first is largely restricted to a broad Southwest-Northeast band across the mid-latitude of New Brunswick, running from Fredericton to Bathurst with sporadic sites elsewhere (Figures 3 and 7). The second subpopulation in Nova Scotia occurs mainly on the east coast of southwestern Nova Scotia (in Shelburne and Queens counties), with sporadic sites throughout the eastern mainland. The Ontario subpopulation consists of a small cluster of sites from Thunder Bay west to the Quetico region in Rainy River District. Records from western Canada have been determined to be other species. There is very little likelihood of movement between the three subpopulations as the distances are large and both the Bay of Fundy and a large amount of land separate Nova Scotia and New Brunswick occurrences, and a very large distance separates Ontario from others (see Life cycle and reproduction).

Extent of occurrence and area of occupancy

The calculated extent of occurrence (EOO) was 67,652 km² and the index of area of occupancy (IAO) was 344 km².

Search effort

Pre-2016 searches

Search effort is summarized in several ways. The pre-2016 sites for F. leucosticta in each province as well as the sites that have been visited in other surveys for lichens in the Pannariaceae but where F. leucosticta was not recorded are shown in Figures 3 to 6. A second set of maps shows the recently verified (2016 to 2017) occurrences in each province as well as sites where the lichen was not found, although the habitat appeared to be suitable (Figure 7 to 10). Note that the place where the lichen is found is termed a site. If one or more trees are colonized close together at the site, they are counted as a single occurrence. If one or more trees are colonized at a distance greater than one kilometre (a distance greater than propagules are generally disseminated on a regular basis) from the first site, the tree or group of trees would be counted and regarded as a separate occurrence. Where occurrences are found at greater distances than the propagules ever normally disperse, for example, between Ontario and New Brunswick, the lichens are regarded as belonging to separate subpopulations in the sense used by IUCN.

The search effort is also summarized as the number of person-hours spent searching. In total, 785 hours were spent searching for F. leucosticta in 2016 to 2017; Nova Scotia had the most person-hours followed by New Brunswick, Ontario, and Quebec (Table 1). In total, 25 people contributed to these searches.

Thirdly, the search effort is summarized as the number of trees examined in New Brunswick and part of Nova Scotia (Table 2). In New Brunswick, almost 10,000 trees were inspected; in Nova Scotia, 761 trees were inspected. In this report, observers are shown by initials: CP = Chris Pepper, CV = Cole Vail, DS = Dwayne Sabine, EH = Eleni Hines, FA = Frances Anderson, JG = Jean Gagnon, KD = Kendra Driscoll, RB = Richard Blacquiere, RC = Robert Cameron, SB = Samuel Brinker, SC = Stephen Clayden, SH = Sean Haughian, SS = Steven Selva, TN = Tom Neily, CS = Chad Simmons.

Nova Scotia totals:
Hosts trees: 67
Searched trees: 761
Trees ratio: 0.088
Total of thalli: 448
Thalli host tree: 6.69
Thalli searched trees: 0.589

New Brunswick totals:
Hosts trees: 247
Searched trees: 9999
Trees ratio: 0.025
Total of thalli: 764
Thalli host tree: 3.09
Thalli searched trees: 0.076

Until 2016, F. leucosticta was not regularly targeted for specific searches in Canada, but considerable effort has been expended to monitor related cyanolichens, especially members of the Pannariaceae. Consequently, a “Target Group Sampling” approach (Ponder et al. 2001) can be applied to infer historical search effort. Search effort before 2016 has varied among provinces, based on the availability of naturalists, biologists, or lichenologists. For example, between 2003 and 2012, lichenologists estimate that they spent over 3000 hours searching for Erioderma pedicellatum (Boreal Felt Lichen) in Nova Scotia (COSEWIC 2014). E. pedicellatum grows on Balsam Fir in wetlands. Extensive preharvest surveys are done on Crown lands by experienced lichenologists as part of the Special Management Practice (Nova Scotia Department of Natural Resources 2018). En route to and from the Balsam Fir habitats, the lichenologists passed through Red Maple and other wet habitats, where they recorded rare lichens, especially the cyanolichens. In New Brunswick, Stephen Clayden has conducted general inventories of Eastern White Cedar swamp forests for over a decade.

In New Brunswick (NB), prior to recent survey efforts, F. leucosticta was collected 23 times from 13 sites (Figure 3). The collections are held at the New Brunswick Museum (NBM). One was made from a single site in each of Charlotte and Saint John counties, two collections were made in Restigouche County, two were made in Kent County (at two sites), eight were made in York County (at five sites), and eight were made in Northumberland County (in Goodfellow Brook Protected Natural Area). These were all made in the course of more generalized macrolichen surveys in lichen-rich habitat. The oldest collection was made by Wolfgang Maas in 1986; most others were made after 2005 by SC (often with SS or KD), or by DS. For details of many of these records see Consortium of North American Lichen Herbaria (2017). The CNALH records also include 297 records of other cyanolichens, and there are a further 63 collections from intensive mycological forays that took place in New Brunswick, where observers could reasonably have been expected to detect F. leucosticta, if it was present. The collected Pannariaceae specimens are at the New Brunswick Museum.

In Nova Scotia, 63 records from 24 sites documented F. leucosticta prior to 2016 (Figure 4), but not all were accompanied by collected material. These records were predominantly from Shelburne County, with 38 observations from 13 sites. All have multiple collections associated with them. Another 15 observations and collections were from three sites in Queens County. Four collections were from four sites in Halifax County, and three records were from two sites in Digby County. The other two records were from a single site in Annapolis and Lunenburg counties. The earliest collection of F. leucosticta was made by Hinds and Hinds (1999). The majority of observations in Nova Scotia were made after 2005 by SC, TN, CP, RC, and FA. Some were recorded opportunistically, but most were made during contracted surveys for other at risk species as part of pre-cutting assessments. There are approximately 1400 records of other at risk cyanolichens in the extensive database maintained by the Mersey Tobeatic Research Institute, and there are 139 cyanolichen records from the province that are held by other herbaria (Consortium of North American Lichen Herbaria 2017).

In Ontario, three sites of F. leucosticta were reported prior to 2016. One was from Algoma District in Lake Superior Provincial Park with a single 1993 collection by S. Sharnoff on the Nokomis Trail near Old Woman Bay. The second area is from the Rainy River District in western Ontario, where it was collected by early American lichenologist Bruce Fink, who visited the Emo area in July of 1901 and made over 20 F. lecucosticta collections (most are replicates of material from one area with the same collection number), all labelled “on cedar in swamps”. A third specimen was collected in the Nipissing District in central Ontario. This collection was made by Roy Cain in 1935 on a decayed log along the Gull Lake Portage, Lake Temagami. It was originally identified as F. leucosticta by Albert William Herre. The specimen at the Canadian Museum of Nature appears to have gone missing but there is a duplicate collection in the Field Museum in Chicago which was re-examined in 2017 by R.T. McMullin and found to be misidentified. There are 234 other Pannariaceae records (Consortium of North American Lichen Herbaria 2017) and notable collectors include C. Wetmore and I.M. Brodo.

In Quebec, three collections were reported (Consortium of North American Lichen Herbaria 2017), but all are older than 65 years, and two were found to have been misidentified. There were two records in the Field Museum, Chicago. In 1943, E. Lepage purportedly collected F. leucosticta, along with several other lichens, on a day trip spent collecting along the Rimouski River, near the Rapide du Bois Brûlé. This specimen was recently re-examined by FA and found to have been misidentified. The second Field Museum collection was made in 1939, by Brother Marie-Anselme in the vicinity of Saint-Félicien, in Comté de Lac-St-Jean (Accession No. C1005165F). When photographs of the herbarium label and annotations were examined (Consortium of North American Lichen Herbaria 2017), it appeared to be a different species. Originally it was recorded as Pannaria microphylla, but in 2000 the name was revised to Fuscopannaria leucophaea (Vahl) P.M. Jørg. The only other record from Quebec was made in 1888 near Lac Clair, approximately 50 km north of Montréal but no collector information is listed on the packet (Harvard University 00437227). A possible duplicate collection, also made in 1888, is from the herbarium of H. Willey (Smithsonian 2878810). Again, no collector is listed for this record. Nevertheless, J. Macoun was known to have collected extensively in Canada in 1888 and may have made both collections. No detailed locality notes are available on any of these packets. Possible associated geographic data appear to have been added after the fact by museum staff, making relocation extremely difficult. Moreover, the Lac Clair area has undergone extensive agricultural and residential development since 1888, suggesting that even if the original identifications were correct, suitable habitat is no longer likely to exist. There are 1105 records of lichens in the Pannariaceae (Consortium of North American Lichen Herbaria 2017) indicating significant search effort for cyanolichens in the province.

Several collections of F. leucosticta have been reported from other provinces in Canada, but have proved to be misidentified. The single Newfoundland collection from Little Ridge, Trinity Bay, by A. Waghorne (University of Minnesota 017101), identified as F. leucosticta, has since been revised to Pannaria rubiginosa (by S.R. Clayden). Specimens reported to be F. leucosticta from British Columbia and the western United States (Figure 2), have been re-examined by I.M. Brodo and shown to belong to another species, Fuscopannaria leucostictoides (Ohlsson) P.M Jørg. A record from the Kananaskis area in Alberta (CANL 102211) was also recently examined by R.T. McMullin at the Canadian Museum of Nature and found to have been misidentified.

Recent searches

In New Brunswick, most of the search effort for F. leucosticta consisted of dedicated sampling trips and surveys of potentially suitable sites (Figure 7). Over 207 person-hours were spent in 2016 to 17 searching for F. leucosticta in New Brunswick. SH and KD surveyed former sites and nearby suitable habitat near Clark Point Protected Natural Area, Ten Mile Creek, New River Beach, and Oromocto Lake. Later in the summer of 2017, SH, SC, KD, and FA (with CV or EH - student research assistants from the NBM) spent 5 days, 10 days, 5 days, and 3 days, respectively, searching for F. leucosticta and other rare lichens and bryophytes in Spednic Lake Protected Natural Area for the BiotaNB program (cf. Drost 2017). SH and FA also conducted surveys when suitable habitat was encountered when hiking throughout New Brunswick and Nova Scotia. RB and SH spent 7 days surveying high probability sites throughout the northern and eastern parts of New Brunswick. In total, observers scanned an average of 463 potential host trees in sites where F. leucosticta was found to be present, and 256 trees in sites where the species was not detected. Once the species was found at a site, the distance walked was extended and estimated to be about (5.4 km) greater than at sites where F. leucosticta was not detected (1.9 km). This difference represents the early recognition of poor sites where the lichen was unlikely to be found and economized on available search time.

In Nova Scotia, from winter 2016 to summer 2018, approximately 433 hours were spent conducting extensive surveys for epiphytic cyanolichens. Between winter of 2016 and summer of 2017, 133 hours specifically targeted F. leucosticta. The targeted surveys were led by RC and TN in Halifax County, and by FA and TN in Digby, Shelburne, Lunenburg, and Queens counties. Surveys by CP in Queens and Shelburne counties were conducted as part of other floristic surveys over the winter of 2016 to 2017. All but five previous sites of F. leucosticta were revisited during these surveys (Figure 8).

Between March and August 2018, SH recorded the presence and abundance of F. leucosticta opportunistically while doing site selection and sampling for a study on the effects of clearcut edges on lichen communities in mixedwood swamps. This included approximately 120 hours (300 person-hours) of extensive surveys during the site-selection phase, 160 hours (320 person-hours) of occasional observation in suitable habitat during the site-installation phase, and an additional 100 hours (100 person-hours) of intensive surveys during the sampling phase. The extensive surveys involved SH and one or two assistants walking much of the extent of approximately 180 potentially suitable (identified as suitable using GIS queries) habitat polygons across the province, with a focus on observing stand structure, lichen community composition, and cut boundary delineation, using a wandering transect method similar to the targeted F. leucosticta surveys. Occasional observations during the site-installation phase consisted of infrequent glances at suitable host trees that were previously unnoticed; considerably less effort was spent looking for lichens at this time, so these hours are not included in the search effort totals. Intensive surveys included the recording of all cyanolichen species growing upon the north- and south-facing sides of 21 Red Maple trees in each of 10 study sites, at regular sampling intervals from a clearcut edge. Each tree was observed (by SH) for an average of 20 minutes, depending on the richness of the epiphyte community. Because no thalli of F. leucosticta were detected through intensive surveys that had not already been detected during the site-selection phase, this search effort is not included in the search effort totals.

In Ontario, SB has made extensive surveys for rare plants and lichens (Oldham and Brinker 2011; Brinker 2017; Lewis and Brinker 2017). He undertook surveys for F. leucosticta during fieldwork that brought him within range of suitable habitat (Figure 9). SB also made several dedicated collecting trips to areas that he or others had previously visited and seemed to be possible F. leucosticta habitat. He searched in the general vicinity of two sites where the historical collections had proved to be correctly identified: Emo, and Lake Superior Provincial Park. SB and others also spent 123 person-hours searching for F. leucosticta during other field surveys in Ontario.

In Quebec, searches for F. leucosticta were carried out by JG or by JG and FA, when doing general lichen surveys in botanically interesting habitats (Figure 10). Efforts were biased towards southeastern Quebec, where habitats of higher quality were presumed to exist for F. leucosticta, due to the similarities with northern New Brunswick where the lichen was known to occur. Approximately 22 person-hours were spent searching for the target species in Quebec.

Habitat

Habitat requirements

Forest and understorey composition

Suitable habitat for F. leucosticta can be identified through the combination of canopy and understorey species. Common canopy and understorey species throughout Canada include Abies balsamea, Alnus incana ssp. rugosa, Rubus pubescens, and Clintonia borealis. In Atlantic Canada, common understorey associates of F. leucosticta include ferns in the genus Osmundastrum (for example, O. cinnamomeum and O. regalis), hollies (Ilex verticillata and I. mucronata), and ash (Fraxinus nigra and F. americana), with peat (Sphagnum) mosses dominating the ground cover in depressions and feathermosses (Hylocomium splendens or Rhytidiadelphus triquetrus) dominating on hummocks. In Ontario, understorey associates include Acer spicatum, Cypripedium reginae, Rhamnus alnifolia, Carex vaginata, Cystopteris bulbifera, and Calypso bulbosa.

Like many cyanolichens, F. leucosticta is restricted to rich (sensu Bowling and Zelazny 1992; Racey et al. 1996), high-moisture ecosystems, such as minerotrophic swamps and riparian forests. This was confirmed in recent modelling work showing that depth to water table and precipitation were two important predictors of its distribution in Nova Scotia after mean annual temperature and distance from the coast (Pearson et al. 2018).

Host trees

Fuscopannaria leucosticta grows on the bark of Red Maple trees in Nova Scotia, and on Eastern White Cedars in New Brunswick and Ontario. The reason for the difference in tree preference between Nova Scotia and other regions is not entirely understood. It may result from a need for a bark with certain moisture-holding ability and pH buffering capacity as well as a suitable microclimate. These conditions are provided by Eastern White Cedar forests that are more common in New Brunswick, and by Red Maple swamps which are more common in Nova Scotia (cf. COSEWIC 2002).

Fuscopannaria leucosticta’s host trees are usually medium- to large-sized, with a noticeable lean and a diameter at breast height (DBH) of 24.8 cm for Red Maple and 26.5 cm for Eastern White Cedar. Occasionally, the DBH can be less than 10 cm, but such trees are always within stands that contain large-sized trees. This suggests that stand longevity, rather than tree age or size, is important in determining habitat suitability (Boch et al. 2013).

In addition to displaying a preference for certain tree species, F. leucosticta displays a preference for heights on the tree bole. Colonies are most often found between 1.0 and 1.8 m up the tree (Figure 11). A decline in frequency was detected above this height, but it is difficult to quantify this without ladders or other access to the upper trunks. Fuscopannaria leucosticta was rarely found below 0.3 m, perhaps due to greater competition with bryophytes and other lichens.

Host trees (both Red Maple and Eastern White Cedar) commonly lean at angles of 20 degrees away from the vertical, with F. leucosticta colonies growing exclusively upon the upwards-facing side of the trunks (Figure 12a,b). This is likely because the upper sides of sloped trunks receive more precipitation and light filtering through the canopy than the lower sides. Field data also clearly indicate an aspect bias for F. leucosticta, with colony frequency increasing along a Southwest to Northeast gradient (Figure 12c). This aspect bias suggests an aversion to microhabitats with high heat loading and desiccation stress. Indeed, the importance of poor drainage was also corroborated by the field surveys in 2017, where sites with F. leucosticta tended to be flat and have standing water (Figure 13).

These lichens are dependent upon old, often leaning trees in old-growth forests, so the number and longevity of host trees should be considered as important as the number of individual thalli, in terms of understanding population size and trends.

Habitat trends

Almost 50% of the total F. leucosticta population in Canada is found in New Brunswick. It appears to be restricted to wet, old-growth forests (sensu Mosseler et al. 2003; Stewart et al. 2003) or undisturbed swamp-forests, provided that they contain Eastern White Cedar. During fieldwork for this report (cf. Haughian et al. 2018 and earlier seach efforts), 21 of 22 (95%) of the newly detected sites in New Brunswick showed no evidence of anthropogenic disturbance, that is, old undisturbed forests. The 22 sites included nine new sites that were discovered before field-testing of the MaxEnt model was done. The number 22 that emerged from that model (Haughian et al. 2018 ) was a coincidence and does not relate to this analysis. In contrast, 56% of the predicted suitable habitats where the lichen was NOT found showed evidence of logging having taken place, probably between 30 and 50 years ago (based on the state of decay of cut stumps that were present). Another 25% showed evidence of dramatic water level changes due to beaver activity.

In New Brunswick, a GIS-based forest inventory was created for the province from aerial photo interpretation (imagery from the 2010s), covering over 80% of the forested area (Crown lands and small private lands). These data indicate that approximately 50% of old cedar-dominated stands in the province are on Crown lands. Approximately 13% (9,748 ha) of these old cedar-dominated stands on Crown lands are in Protected Natural Areas (PNAs) where no harvest is allowed. Other areas are deer-wintering areas, riparian areas or are part of the operationally constrained land base (for example, steep areas, wet areas). Thus, they are not available for clearcut harvest, but may be available for some level of harvest. Overall, there was about a 17% decline in the amount of old cedar-dominated forest between 1980 and 2010 (New Brunswick ERD preliminary analysis). This estimated decline may be an overestimate because some stands that were identified as Eastern White Cedar in the 1980s inventory were actually not cedar. However, some stands that were identified as not containing Eastern White Cedar occasionally do have it, so the errors may be balanced. This decline is likely to continue as forestry extends into Eastern White Cedar and Red Maple swamps, which were previously not much exploited. Indeed, recent changes in forest management strategy in New Brunswick suggest that logging of old forests is likely to continue at higher-than-historical levels (Province of New Brunswick 2014). However, in August 2018, the New Brunswick provincial government released a review of the 2014 forest strategy. One of the commitments was: “over the next five years, designate an additional 150,000 hectares of Conservation forest”. This may include additional old cedar forest. Furthermore, there is a commitment in New Brunswick to set aside more land as protected areas (Pathway to Target 1), which may lead to additional old cedar forest being protected (Province of New Brunswick 2018). Using information from the most recent forest inventory layer (NBERD preliminary analysis 2018), Sabine personal communication (2019) calculated that there are 7,863 old, wet cedar stands (37,078 ha). These haven’t had forest harvest activity since at least the early 1980s (beginning of the inventory). The cedar stands are across central New Brunswick, the zone that the Haughian et al. (2018) model indicated was more suitable for F. leucosticta. When considering a minimum stand size of 12.5 ha (for a circular stand with a 200 m radius), there are 430 stands totalling 8,239 ha. Thus, there may be about 15% more potential habitat for the species in New Brunswick than was estimated for the draft report which used a then available figure of 6,666 stands (“polygons”) of old unmanaged cedar, with an average stand area of 7.7 ha (range: 0.01 to 154.3 ha) (Clayden, personal communication 2019).

In Nova Scotia, there are no long-term harvest plans available to project trends in the harvesting of particular areas or types of forested habitats. Currently, information on planned harvests is only being released county by county and area by area (Bayne 2019). However, at the present time, forestry outputs are well-documented in the province. These suggest that the utilization of species that are common in old-mixedwood swamps for pulpwood and biofuel has been increasing over the last 10 years (Nova Scotia Department of Natural Resources 2017). There are recent amendments to the Province’s Special Management Practices (SMPs) for forests on Crown land in relation to species at risk and to buffer sizes around these species. These amendments protect several species but exclude F. leucosticta. Counter-intuitively, the implementation of these SMPs could lead to an increase in the amount of forest harvesting in Shelburne and Queens counties (Duncan Bayne personal communication 2018), where F. leucosticta is most common and abundant; this is because the forest sector has been avoiding harvesting in these places in recent years, due to the lack of certainty surrounding SMPs for lichens. On the other hand, these SMPs may confer increased protection to species that often co-occur with F. leucosticta (Nova Scotia Department of Natural Resources 2018). This applies where F. leucosticta occurs within the bufffer for that protected species. Buffers for these associated lichen species at risk vary from 100 to 200 m. F. leucosticta would have to occur in the same occurrence as the associated species before effective protection would be achieved. Three of 61 occurrences in Nova Scotia (Table 3) that have large numbers of F. leucosticta thalli (80,113, and 173) should be given protection by the presence of other species at risk (Nova Scotia Department of Environment 2018). Nova Scotia’s approach to forestry was recently reviewed (Lahey 2018) and the Nova Scotia provincial government has committed to “ecological forestry” in the future. Ecological forestry places a greater emphasis on preserving ecological values over economic ones, and early implementation has already resulted in the doubling of species at risk staff and associated resources (Hurlburt personal communication, 2019). As in the case of New Brunswick, the outlook seems brighter, but only action to curtail clear cutting will help species at risk such as F. leucosticta. One element under development is forest harvest environmental assessments, which should help wildlife species under threat (Nova Scotia Government 2919).

In Ontario, the known sites for F. leucosticta all fall within the Northwest Region, specifically in the Black Spruce Forest Zone (035) and the Lakehead Forest Zone (796), but it is not yet known whether the recorded sites of F. leucosticta fall within stands designated for cutting. The number of old cedar forests and swamps being harvested appears to be increasing in Ontario (personal observation, SB), perhaps due to efforts of the Ontario Ministry of Natural Resources to capitalize on a species it deems to be underutilized (Buda et al. 2011).

Biology

Life cycle and reproduction

Fuscopannaria leucosticta’s primary mode of reproduction is by ascospores as there are no asexual reproductive structures such as soredia or isidia. Fruit bodies (apothecia), form and asci are formed within these that each have eight spores. Once mature, the asci eject spores into the atmosphere, where they disperse passively by wind currents. It is not known how far these spores travel, or how long they survive aloft in the atmosphere, but studies of deposition in other taxa have shown that deposition drops off to near zero over a distance of several metres, and thereafter exists at a background (landscape) level (Lönnell et al. 2012). If ascospores land on a suitable substratum within close proximity to a photobiont (that is, a Nostoc sp.), lichen resynthesis begins (Honegger 2008). If the photobiont strain and mycobiont partners are sufficiently compatible, a lichen will begin to form and differentiate into a thallus. In the case of F. leucosticta, development of a hypothallus, which binds the lichen to the substrate, appears to precede other components of the lichen, and is also regularly seen growing through and over the top of bryophytes, suggesting a possible allelopathy.

Thalli as small as 1 to 2 cm² appear to be capable of generating apothecia, but these are typically small apothecia (~0.5 mm in diameter) and produce very few ascospores. Once thalli reach sizes of 40 cm² or more, a profusion of apothecia is typically observed in the middle of the colony. Fuscopannaria leucosticta is unusual in that spore production within each apothecium appears to be low compared to that of other foliose cyanolichens (personal observation, SH and SC). Although no quantitative data were collected, this can be easily observed by dissecting the apothecia of F. leucosticta and comparing spore densities with, for example, Protopannaria pezizoides.

It is not currently known how long it takes F. leucosticta to develop from a germinating ascospore to a productive mature colony, nor is the lifespan known. Some common, rapidly growing lichens that associate with green algae like Trebouxia, can take as little as 5 to 10 years, in a temperate maritime climate, to develop a thallus with reproductive bodies on it (Eaton and Ellis 2014). Other lichens require 9 to 22 years in boreal rainforests (Larsson and Gauslaa 2011). On long-lived trees, epiphytic cyanolichens may live for an average of 40 years (Öckinger and Nilsson 2010). The oldest thallus of F. leucosticta that has been relocated in the field was 12 years old. Apothecia form on quite small thalli of F. leucosticta, and the generation time is estimated to be 12 years for the purpose of this report, but it may be longer than this.

Fuscopannaria leucosticta has a preference for leaning host trees (mean lean angle of 20°), so the lifespan of a particular thallus may be determined by the longevity of the host tree. Once trees develop a lean of more than 15°, the chance of stem failure increases exponentially; lean angles of 20° or more are at considerable risk of falling (Coder 2000). Such trees may be removed in managed forests for safety reasons (Coder 2000) but are not removed on Crown lands.

The cyanobacterial partner of the lichen symbiosis is a Nostoc sp., which can form colonies independent from lichens on soil, tree bark, and in the water-retaining capillary spaces of bryophyte colonies (Dodds et al. 1995; Zackrisson et al. 2009). Lichen-forming fungi often require particular strains of Nostoc and cannot develop unless they are on the bark surface, but no molecular studies have been done with F. leucosticta to identify the preferred strain.

Physiology and adaptability

Lichens like F. leucosticta, with a cyanobacterial photobiont, have the capacity to fix atmospheric nitrogen (Nash 1996). Depending on the lichen species and other environmental constraints, such as the availability of phosphorus (Knops et al. 1996; Hooper and Vitousek 1998), the fixed nitrogen is largely retained in the lichen until the thallus decomposes (Nash 2008). In cyanolichens such as F. leucosticta, both photosynthesis and nitrogen fixation are dependent upon the availability of liquid water to activate the necessary enzymes (Antoine 2004), and to ensure energy inputs from photosynthesis (Dodds et al. 1995). Fuscopannaria leucosticta, like many other cyanolichens, does not thrive in habitats with a low availability of liquid water (Rikkinen 2015).

Because the photobiont in F. leucosticta is a cyanobacterium, this lichen can contribute to nitrogen nutrition of the forests it inhabits. Cyanolichens, in general, are responsible for fixing a significant proportion of the nitrogen that enters cyanolichen-rich ecosystems (Coxson and Nadkarni 1995). In forests of central B.C., for example, trees that host cyanolichens have higher levels of N from atmospheric sources than those that do not (Kobylinski and Fredeen 2015), and increased soil nitrogen has been observed under terrestrial cyanolichens (Knowles et al. 2006). While the contribution of F. leucosticta would likely be small relative to that of more abundant species, the cyanolichen community as a whole should be considered an important functional component in swamp forests of eastern Canada.

Dispersal and migration

In lichens: (1) small propagules are dispersed more widely than large ones, and (2) large propagules have a greater chance of growing and producing adult colonies than small ones. In lichens, sexually produced propagules (that is, ascospores in apothecia) are much smaller than asexual ones (for example, soredia, isidia, and thallus fragments). Consequently, lichens which rely primarily upon sexual reproduction are expected to disperse widely but be relatively ineffective at colonizing new habitats locally. In contrast, those that rely primarily upon asexual reproduction (isidia or soredia) are expected to occupy most available substrata within a localized habitat but be relatively ineffective at colonizing new habitats (Hedenås and Ericson 2008; Fedrowitz et al. 2012). Fuscopannaria leucosticta produces apothecia, but no asexual reproductive structures (Jørgensen 2000) and so is hypothesized to be relatively effective in long-distance dispersal, but relatively ineffective at expansion within suitable habitats. This is supported by the low proportion of potential host trees (Eastern White Cedars) upon which F. leucosticta was detected during 2017 surveys in New Brunswick (mean = 2.6%, SD = 2.6%).

Fuscopannaria leucosticta appears to compete effectively with other epiphytes on the lower bole of many host trees, and is occasionally found as a sprawling vertically elongated colony covering as much as 50% of the lower bole of a host tree. One out of every 5 to 10 trees displayed this pattern in New Brunswick, and anecdotal evidence suggests similar frequencies in Nova Scotia. This pattern suggests that a well-developed colony can spread down and perhaps up by scales being broken off and transported very short distances by water movement (Armstrong 1987) or activity of animals (McCarthy and Healy 1978). These thallus scales, if they become re-attached to the bark, can develop into a large secondary colony which may or may not be confluent with the original. In conclusion, it seems likely that F. leucosticta is transported to new habitats via wind-blown sexually produced spores, and that the few spores that successfully resynthesize the lichen can form an extended colony on a tree or cluster of trees from locally distributed thallus fragments.

Given this strategy, it is surprising that F. leucosticta is not more common across the landscape, or more abundant within apparently suitable habitats. It also surprising that it is less common than many closely related Pannariaceae that reproduce only asexually (for example, Pannaria conoplea). One explanation may be that, in addition to requiring suitable habitat and host trees, colonization of new habitats requires a specific strain of cyanobacterium for resynthesis of the lichen; it may even require a strain used by predominantly asexual cyanolichen species (for example, P. conoplea or Fuscopannaria sorediata), or by liverworts like Frullania spp., which have water sacks colonized by cyanobacteria (Belinchón et al. 2015). Such facilitation has been hypothesized to occur between Frullania asagrayana and Erioderma pedicellatum (Cornejo and Scheidegger 2016).

Interspecific interactions

Fuscopannaria leucosticta is often associated with several understorey species, and other epiphytic mosses, lichens, and liverworts. In an inspection of the 19 herbarium collections at the New Brunswick Museum, the three most common associates were Frullania asagrayana and Radula complanata, two common corticolous liverworts that are most frequently found on hardwoods, and Ptilidium pulcherrimum, a generalist corticolous liverwort. In addition, Parmelia sulcata, Sanionia uncinata, Dicranum montanum, and D. viride were each found associated with F. leucosticta in three herbarium collections from cedar trees. While none of these species are rare, their combination underlines the rich corticolous community of bryophytes and lichens that develops in old, wet to mesic hardwood or cedar forests.

Population sizes and trends

Sampling effort and methods

The fieldwork goals for this report were to: (1) visit as many known sites for F. leucosticta as possible to verify that the species is still present, (2) visit as many likely sites (based on recommendations from local naturalists and through the use of GIS habitat data) as is possible, given time constraints, (3) obtain accurate counts of the number of thalli, host trees, and sites for the species, (4) photograph and collect voucher specimens, as appropriate, and lodge specimens at the New Brunswick Museum, and (5) to obtain sufficient ecological data to accurately describe the autoecology of F. leucosticta.

Surveys in 2017 consisted of timed searches within habitat that was deemed to be suitable for hosting the species. In New Brunswick and Ontario, this generally meant limiting searches to old stands of Eastern White Cedar with a high water table, or a hummock and hollow microtopography that suggested ephemeral flooding. In Nova Scotia, similar habitats were sought, albeit while looking for old Red Maple trees instead of cedar, because cedar is rare in the southern portion of the province. In addition to these trees Black Ash (Fraxinus nigra) was inspected in suitable habitat. Both leaning and upright trees were assessed to determine lean angle, but extra attention was paid to leaning trees during searches. During a typical search, observers would walk a wandering transect through the stand for approximately 1 to 2 hours, at a pace of approximately 0.5 to 1 km per hour, and spend 2 to 5 seconds scanning each cedar tree from the ground to approximately 4 m in height. When leaning trees were seen in the distance, observers walked towards them and carefully examined the upper surface.

For those sites in which scanned trees were counted, F. leucosticta was detected on an average of four out of every 100 trees, but prevalence varied widely among sites, ranging from 1 thallus per 285 trees (West of Red Pine Knoll) to almost one thallus per ten trees at Goodfellow Brook (Table 2). Given this knowledge, observers doing survey work in the future can be confident that they have suitably assessed a site if they have conducted visual scans of at least 300 trees per site before concluding the species is not present. Depending on the density of the vegetation, this search effort could be realized in approximately one hour by two observers, while walking over approximately 1 km.

In addition to counting thalli and trees, habitat data were collected in New Brunswick and parts of Nova Scotia. Data were recorded at three levels: habitat, substrate, and thallus. Habitat data included dominant canopy species, canopy cover, ground slope and aspect, and a qualitative description of moisture regime. Substrate data included the DBH and species of host tree, the number of colonies per tree, the height range of colonies on the tree, the lean angle of the tree, the aspect of the tree’s lean, and the identity of associated epiphytic lichens or bryophytes. Thallus data included the size of the contiguous colony, the median direction the colony was facing, and the percent of the colony that was grazed or necrotic.

Because field surveys were often limited to less than a complete census for logistical reasons, and because data were incorporated opportunistically from multiple sources during the assessment process, several methods were used to improve the realism of population estimates. When complete thallus count data were not available, but tree counts or detections were, the number of colonies was estimated by multiplying the average number of thalli per tree (for a given province) by the number of host trees or detections known for that site. This method was used to estimate the number of thalli for sites visited by CP before the status assessment began, as well as the number of thalli in five sites that could not be revisited in Nova Scotia. Nevertheless, the count of the number of known thalli should be regarded as conservative, because surveys for the most densely populated sites (for example, Goodfellow Brook Protected Natural Area) in New Brunswick and Little Bon Mature Lake in Nova Scotia) did not include all suitable habitat patches within the site.

To ensure that the primary observers for this study used similar survey and counting methods, two large sampling trips of 2 to 3 days were made near the beginning of the field season. These trips involved FA, RC, SC, SH, and TN, and focused on standardizing survey techniques and search images. These took place in the Shelburne area of Nova Scotia, and in the Miramichi area of New Brunswick, so those surveying for this lichen could see high-quality sites in each province.

Abundance

Based on survey data collected between 2016 and 2018, the total known population of F. leucosticta in Canada is 1663 mature thalli, distributed among approximately 502 host trees in 88 sites (Table 1). The largest known subpopulation is in Nova Scotia (822 thalli known from 224 trees in 57 sites), followed by New Brunswick (764 thalli on 247 trees in 26 sites), then Ontario (77 thalli on 31 trees in 5 sites). The mean number of thalli per tree was 3.1 in New Brunswick, 6.7 in Nova Scotia, and 2.5 in Ontario.

The total possible subpopulation sizes were estimated for both New Brunswick and Nova Scotia using a linear extrapolation, based on recently developed distribution models (Table 1). The projected possible subpopulation size for New Brunswick was 4,315 thalli. The projected subpopulation size for Nova Scotia was 4,311 thalli (see Technical Summary and Appendices 2 and 3 for details). The data from the small subpopulation in Ontario were insufficient to employ the same estimation methods, but using an alternative method, a local expert (SB) estimates the possible subpopulation could be 639 thalli. When combined with the number of observed thalli in Nova Scotia and New Brunswick, the estimate for the total population in Canada is 9,265 individuals.

Survey efforts in Ontario were more limited than in the Atlantic Provinces. Searches by SB in 2017 did not re-locate any F. leucosticta individuals in Lake Superior Provincial Park in what appeared to be suitable old-growth or mature forests with little evidence of anthropogenic disturbance. This cedar-dominated forest was found along and adjacent to the trail (which is still present). After searching, it was concluded that this occurrence is no longer present. Suitable habitat may exist elsewhere in the park but could not be searched given time constraints and inaccessibility. Similarly, searches of remnant Eastern White Cedar swamps within a 50 km radius of Emo in 2017 were unsuccessful. Given the likelihood of high nitrogen pollution from extensive agricultural development around Emo, it is unlikely that F. leucosticta still occurs nearby. However, SB discovered six new occurrences in Ontario in 2016 and 2017 as part of a combination of routine forest land surveys and dedicated searching.

Fluctuations and trends

Population trends are currently difficult to assess, because 2017 was the first year that data were collected on the number of thalli and number of colonized trees. The surveys in 2017 yielded new sites, but none showed evidence of past stand-replacing disturbance (sensu Pickett and White 1985). Thus, it seems unlikely that any of the new detections represent recent colonizations. Enough previously known sites in New Brunswick and Nova Scotia were re-visited to identify that there are occurrences where the lichen no longer exists (Figure 14) and to extrapolate average loss rates. The same was done for Ontario for consistency with the other provinces (Table 4).

Fuscopannaria leucosticta apparently requires undisturbed old-growth forest to thrive (Haughian et al. 2018). From observation, it is assumed that (1) all thalli that were detected on residual trees in recently logged stands will succumb to necrosis and slough off the trees in a short time (that is, 1 to 3 years), (2) thalli in stands that were expected to be logged (based on the presence of marking tape during the surveys in 2016 and 2017) will either be directly lost or will succumb to necrosis and slough off the trees shortly after logging takes place (that is, 2 to 4 years), and (3) future losses will occur at approximately the same rate as past ones. Using these assumptions, losses were projected, assuming a 0.93% annual reduction in thalli for the next three generations (36 years) in all provinces, for all thalli (Table 5). The decline in the number of thalli over the last 10 years is unknown as thalli were not generally counted prior to 2017 but simply recorded as ‘present’. For this reason, the annual loss rate of thalli is inferred using the proportion of lost sites over the last 10 years, divided by ten, that is 0.93%.

The rates of population decline were expected to differ among provinces, and to be lower in protected than unprotected habitats. Unexpectedly, there were differences in the loss rates between protected vs unprotected habitats and between provinces. For example, the estimated annual loss rate (for sites) on unprotected lands in New Brunswick was 1.9%, and no losses were recorded in protected lands. In contrast, unprotected lands in Nova Scotia had losses of 0.41% of sites per year, whereas the loss in protected sites was 1.67%. The differences between provinces for unprotected sites likely results from variations in forest harvesting. The differences between protected sites cannot be readily explained. However, per-province annual loss rates, in protected and unprotected habitats, were used to estimate the overall (national) annual loss rate and so calculate future population sizes (Figure 15, Table 4).

If losses of old, unmanaged forests continue, combined with other sources of mortality, it is estimated that there will be losses of 0.93% per year for the Canadian population (Tables 4, 5). Over three generations (36 years), declines of 45% in mature individuals (thalli) are likely to occur in Canada (Figure 15). This decline was calculated using the methods outlined in Appendices 2 and 3.

Because projected population declines depend heavily upon forest harvesting rates, declines could be substantially reduced if additional habitats are protected. In particular, protecting the sites with the largest numbers of thalli (for example, the Little Bon Mature Lake or Canada Hill sites in Nova Scotia, and Albert Lake or Pigeon River sites in Ontario) could lead to considerably greater population stability. On the other hand, the projected losses may be somewhat greater than estimated, as harvesting in lichen-rich forests has been stalled in Nova Scotia in recent years (while Special Management Practices and Status Assessments have been under development) and harvesting will likely soon increase (see Habitat trends).

On Crown Lands, Special Management practices (SMP) have been introduced in Nova Scotia following ongoing monitoring for the extremely sensitive cyanolichen Erioderma pedicellatum (Nova Scotia Department of Natural Resources 2018). Studies have revealed that a buffer zone of 100 m is insufficient, and a Special Management Practice now involves leaving a 500 m buffer around occurrences following pre-harvest surveys on Crown land. Other listed, less sensitive lichens are protected by either a 200 m or 100 m buffer zone around occurrences (Nova Scotia Department of Natural Resources 2018), but F. leucosticta was not included in the list. While some protection may be afforded to this species by the presence of the other recognized rare lichens, its somewhat different habitat, and occurrence on White Cedar, means that the current Special Management Practice will not fully protect F. leucosticta on Crown land. Furthermore, the Special Management Practice does not apply to forestry activities on privately owned land where many occurrences for F. leucosticta have been documented.

Rescue effect

This is expected to be very low as there are no nearby thalli of F. leucosticta growing in the USA. The nearest occurrences to the Ontario subpopulation are in Minnesota, Wisconsin, and Michigan, where the species has largely disappeared and has not been collected within the last 15 years. In addition, this lichen has not been found since 1986 in Pennsylvania. In the past, it was recorded in several New England states, but may be extirpated there, not being found since 1953 in Maine.

Threats and limiting factors

The threats calculator assessment for Fuscopannaria leucosticta is high to medium (Appendix 1). The threats, reviewed below, were categorized following the IUCN-CMP (International Union for the Conservation of Nature – Conservation Measures Partnership) unified threats classification system. This is based on the standard lexicon for biodiversity conservation of Salafsky et al. (2008). Threats are presented in decreasing order of severity. The greatest threat to F. leucosticta is current and future logging and wood harvesting. However, there are other threats which are also likely to have an impact on F. leucosticta. The main potential threats for each occurrence are listed in Table 3. The various threats to F. leucosticta are discussed below using the Threats calculator headings.

Logging and wood harvesting (Threat 5.3)

It is uncertain whether harvesting in marginal or wet forests will continue at the current rate. This seems likely given recent trends that project increased pulp and fuelwood harvest in forests that are marginally valuable for timber in three provinces. While there are protected forest areas in each province, 77% of the total known population of F. leucosticta in Canada occurs outside these areas and is at risk of being lost due to wood harvesting activities (Table 3).

In New Brunswick, five newly detected occurrences (representing 81 thalli) were already flagged with cutblock-boundary tape during the surveys for this status report, and one (representing 34 thalli) was recently cut. Slightly necrotic thalli were also detected on several trees in retention patches at the Blissfield Clearcuts site. This suggests that edge effects will lead to the loss of further thalli. Losses of 13% of the total known population of F. leucosticta in New Brunswick are likely over the next 1 to 2 years in the cutblocks that have been flagged (flagging usually indicates that logging will take place in 1 to 2 months). Even if the host trees are retained, thalli will likely only remain alive in retention strips for an uncertain period of time after logging. They will eventually succumb to negative edge influences (sensu Harper et al. 2005) that include increased heat and desiccation stress. Cyanolichens, like F. leucosticta, have been shown to be especially sensitive to stress due to edge effects (Gauslaa et al. 2019; Haughian & Harper 2018) as they require liquid water to initiate and maintain photosynthesis and nitrogen fixation. Logging has resulted in the loss of three other occurrences in New Brunswick within the last ten years (Figure 14).

In Nova Scotia, several previously recorded thalli may also have been lost because of adjacent logging activities. In addition, several newly discovered occurrences will likely soon be lost due to logging activities that felled host trees or left residual host trees isolated. This was inferred from the presence of several necrotic thalli on residual trees in four newly detected sites. For example, extensive necrosis (bleaching) was detected on residual trees in or adjacent to clearcuts at the Blue Hill Mud Lake occurrences, on the Crane Lake occurrence, and the occurrence southeast of Burnaby Lake.

In Ontario, one site (discovered in 2016) was noted to have been clearcut in 2017, and another one had considerable logging activity nearby.

Pollution (Threat 9)

Cyanolichens as a group are known to be sensitive to acidification of their habitat (Richardson and Cameron 2004; Hauck and Spribille 2005). Acidification caused by SO₂ emissions and acid rain disrupt photosynthesis (Bertuzzi and Tretiach 2013) and can cause membrane leakage (Häffner et al. 2001). Significant reductions in SO₂ and NO_x occurred in Canada and the United States between 1990 and 2014 (Carou et al. 2008; International Joint Commission 2016), leading to increased soil pH in some areas (Lawrence et al. 2015). However, ecosystem recovery will likely continue to lag behind regulatory changes as soils in other locations have shown only partial recovery or no recovery at all (Lawrence et al. 2015). Consequently, persistent acidic conditions may exceed the buffering capacity of host tree bark, making it unsuitable for colonization by cyanolichens like F. leucosticta (Nieboer et al. 1984). Thus pollution poses a persistent risk to terrestrial ecosystems (Clair and Hindar 2005; Clair et al. 2011).

Climate change and severe weather (Threat 11)

Epiphytic cyanolichens can be negatively affected by changes in climate (Bjerke et al. 2003; COSEWIC 2016). Expected changes to the climate in eastern Canada over the next century include increased mean annual temperatures and a slight increase in precipitation as well as an increased frequency and severity of extreme high temperatures, heavy precipitation events, and earlier spring thaws. This could lead to earlier peak flows in watersheds (Romero-Lankao et al. 2014). In addition, a decline in the frequency of fog events has been detected for recent decades in Atlantic Canada (Wang 2006). Such changes could result in an increasingly negative water balance of thalli, due to increased evaporation and reduced understorey humidity, potentially leading to desiccation stress in cyanolichens (Marini et al. 2011).

There remains significant uncertainty with respect to the impacts of climate change on fog, rainfall, and wind in Atlantic Canada (Lemmen 2016; McClearn 2018). However, F. leucosticta is sensitive to the availability of liquid water. As a result, reduced frequency of rainfall or fog events, and warmer, dryer summers, as exemplified in Maritime Canada in 2018 (and to a lesser extent in summers since 2013), are likely to have a negative impact on the species. For example, the mean monthly temperature in Yarmouth, Nova Scotia, the general area of the province where F. leucosticta is more common, was about two degrees hotter in July and August in the years 2013 to 2018 compared with the period from 1961 to 1990. Furthermore, the rain was 20 mm less for these months between the two periods (Environment and Climate Change Canada 2018). These conditions, not only provide more stress for F. leucosticta, but also enhance the risk for forest fires.

An additional threat is provided by the predicted increase in the number and severity of weather events including storms and flooding. These are likely to lead to more and widespread tree blowdown events. Windthrow of host trees is also likely if the climate warms as there is less time during the year when soils are frozen. Branches may also be broken during extreme snowfall events (Saad et al. 2017). This could reduce the number of suitable host trees for epiphytes like F. leucosticta.

Invasive non-native/alien species/diseases (Threat 8.1)

Gastropod (snail and slug) grazing has been shown to play an important role in structuring epiphyte communities (Asplund and Gauslaa 2008). Expansions of non-native gastropods may negatively impact F. leucosticta and other epiphytic cyanolichens, particularly in Nova Scotia (Cameron 2009). During the fieldwork for this report, grazing damage (indicated by the selective removal of cortical layers, exposing the white medulla underneath) was more extensive on thalli in Nova Scotia (mean of 6.32% of each thallus) than in New Brunswick (mean of 0.68% of each thallus). Some grazing is likely sustainable and may even be beneficial for F. leucosticta, as it may prevent competitive exclusion in lichen communities (Boch et al. 2016) and facilitate the dispersal of lichen colonies via endozoochory (McCarthy and Healy 1978). Nevertheless, the extensive grazing damage detected in Nova Scotia sites may be caused by invasive Arion spp., which are known to damage lichen populations (Asplund and Gauslaa 2008, 2010; Cameron 2009; Moss and Hermanutz 2010). The combination of several stressors (for example, acidification or climate change) may increase cyanolichen susceptibility to grazing damage by limiting the manufacture of anti-herbivory compounds (Baur et al. 1994; Lawrey et al. 1999). Warmer temperatures may also affect the survival or population growth of invertebrate herbivores (Bjerke et al. 2003).

Other ecosystem modifications (Threat 7.3)

Rather than allowing natural regeneration after logging, there is an increasing policy to replant with coniferous species to be harvested subsequently for pulp and wood fibre. The New Brunswick government has committed to increasing the size of wood and pulp plantations from 12 to 21% on forested Crown lands over the next 50 years (Province of New Brunswick 2014). Conversion of old cedar-dominated forests to coniferous wood and pulp plantations would make conditions unsuitable for F. leucosticta. Fortunately, this threat is currently limited to sites that occupy gentle slopes or upland habitats, and for this reason was not considered in the Threats Calculator Assessment. The bark characteristics (water holding capacity, morphology and pH) of Eastern White Cedar that is colonized by F. leucosticta are quite different from pine and spruce bark, which is not suitable for colonization by most cyanolichens. Wood-fibre and timber plantations harbour fewer cryptogamic species than old, structurally complex forests in eastern Canada (Gilliam and Roberts 1995; Ross-Davis and Frego 2002; Veinotte et al. 2003). Plantation canopies are also dense, which makes conditions unsuitable for lichen colonization (Porté et al. 2004; Carnus et al. 2006; Aubin et al. 2008; Cole et al. 2008; Haughian and Frego 2017).

Limiting factors

Fuscopannaria leucosticta is found on the bark of Red Maple (Acer rubrum) trees in Nova Scotia, and on Eastern White Cedars (Thuja occidentalis) in New Brunswick and Ontario. In all three provinces, this lichen grows in mature old wet forests that have been undisturbed for more than 50 years (see Habitat trends). Any combination of threats which affects the habitat requirements are likely to limit the occurrence of this lichen.

Number of locations

Based on surveys, there are at least 1,663 thalli, distributed among 502 trees in 88 occurrences. The number of locations for the White-rimmed Shingle Lichen in Canada is assessed also as 88. This number is used because logging, fires, and alien snail infestation operate at the individual occurrence or stand level. Climate change impacts may operate at a regional level, so there could be as few as 3 locations for the 3 subpopulations, but the number is probably more than ten.

Protection status and ranks

Legal protection and status

Global status

Globally, NatureServe assigns F. leucosticta a status of G3G5 - vulnerable to secure (last reviewed 2000-12-08). The species is considered endangered in parts of Europe and may have been extirpated when acid rain deposition was at its highest intensity in the mid-to-late twentieth century (Jørgensen 1978; Jørgensen and Sipman 2007). F. leucosticta, one of the rarest macrolichens in Europe, was found recently in Greece. It had not been seen on this continent for over a century, when it was recorded from Italy and Slovenia (Spribille 2009).

In the United States, F. leucosticta is thought to have been extirpated from most of New England by the mid-20^th century, persisting only in southeastern parts of the country (Hinds and Hinds 2007). Only three states have rankings for the species: North Carolina (SNR - unranked), Pennsylvania (SNR), Wisconsin (S1 - critically imperilled).

Status in Canada

Fuscopannaria leucosticta has been given a national rank of N2N3 (2015-0607) – imperilled to vulnerable. The species was also assigned a general status rank of N3 (vulnerable) by Canadian Endangered Species Conservation Council (2016).

In addition, the species has been given an S rank under the NatureServe/General Status S-ranks system generated by the provinces and territories together with the CDCs. The rank of S1S2 was assigned to this species for Ontario, by the Natural Heritage Information Centre, while the rank of S2S3 – critically imperilled to imperilled, was given for New Brunswick and Nova Scotia, by the Atlantic Canada Conservation Data Centre.

Habitat protection and ownership

Currently, 33% of known thalli (24% of sites) are protected by harvest limitations (Table 6). In New Brunswick, these include protected natural areas, riparian buffer strips, and provincial and national parks. Approximately 13% (9,748 ha) of old cedar-dominated stands on New Brunswick Crown lands are in Protected Natural Areas where there is no harvest allowed, although 35% of the areas surveyed for F. leucosticta were protected lands. In Nova Scotia, approximately 17.5% of the sites with F. leucosticta were protected lands, including nature and wilderness reserves, riparian buffers, provincial parks, and set-aside stands which contain a SARA-designated ‘At risk’ species. In Ontario, protections for F. leucosticta include only a single provincial park and a nature reserve, but these represent 33% of sites.

Protected areas confer either partial or full protection, depending in part on the proximity of the protected area boundaries; for example, the best habitat for F. leucosticta within Kouchibouguac National Park is along a small section of the southwestern park border. Colonies occur on both sides of this border and even the colonies in the National Park could be affected by altered microclimatic conditions (edge effects) if cutting happened outside this boundary.

While it is not yet known how far clearcuts must be from F. leucosticta thalli to ensure survival, it is likely complicated by the landscape context. For example, if clearcut logging and the accompanying road construction results in a drop of the water table, the negative edge influence will likely extend much farther into the wet forest or swamp than it otherwise would. The impacts of adjacent logging may also be more severe in marginal habitat; sites that only support small numbers of thalli may be less optimal ecologically, and therefore would require smaller changes to become unsuitable. For example, one former site in New Brunswick (Ten Mile Creek) was known to have had a single, small thallus, which was lost after a windthrow event, followed by a limited amount of selective cutting. Richer, or more extensive, sites might survive such small-scale disturbances. Removing sites with many host trees and thalli from the harvestable landbase would likely be an effective strategy to reduce losses from logging and unexpected losses from stochastic natural disturbances.

In July 2018, NBERD provided habitat protection (harvest eligibility) information for a number of sites (194 individual points) for species in cedar swamps in Southwest and Northeast New Brunswick. Of these sites, 76% (147/194) were on provincial Crown land. Of those, 107/147 (73%) of the points occurred in those parts of the Crown forest where no harvesting can occur. The remaining 39 points (27%) were in forest that is eligible for clearcut harvest (20/147) or partial harvest only (19/147), but they may not be harvested (Sabine, personal communication 2019).

Some protection from potential damage caused by recreational development, such as building and using ATV or truck trails, could be achieved through a combination of public education / signage, with restrictions for motorized vehicles in wet habitats, and trail-buffer requirements.

Acknowledgements and authorities contacted

Acknowledgements

Much of the fieldwork in New Brunswick was supported by a grant from the New Brunswick Wildlife Trust Fund, and both the New Brunswick and Nova Scotia governments contributed significantly (cash and in kind) to the project. The Ontario Ministry of Natural Resources and Forestry provided in-kind support for the Ontario component of the project.

The report writers wish to thank the following individuals for their efforts in collecting or sharing data and verifying records: Chris Pepper, Cole Vail, Dwayne Sabine, Eleni Hines, Frances Anderson, Jean Gagnon, Kendra Driscoll, Richard Blacquiere, Robert Cameron, Samuel Brinker, Stephen Clayden, Steven Selva, Tom Neily, and Chad Simmons. Samuel Brinker (National Heritage Information Centre, Ontario Ministry of Natural Resources and Forestry) and Tom Neily provided extensive assistance in Ontario and Nova Scotia, respectively; Jean Gagnon conducted surveys in southeastern Quebec; Kendra Driscoll, Dwayne Sabine, Cole Vail, and Eleni Hines assisted with data collection in New Brunswick; Kara Pearson shared a pre-publication draft of her habitat modelling study for Nova Scotia. Finally, Dr. R. Troy McMullin (Canadian Museum of Nature) inspected several old specimens and searched for additional records in North American herbaria.

Authorities contacted

Sean Blaney, Ph.D., Director, Atlantic Canada Conservation Data Centre.

J. Sherman Boates, Ph.D., Manager, Biodiversity, Wildlife Division, Department of Natural Resources, Government of Nova Scotia.

Jacques Labrecque, Botaniste, Ministère du Développement durable, de l'Environnement et des Parcs du Québec.

Rachel McDonald, Senior Environmental Advisor, National Defence, Government of Canada.

R. Troy McMullin, Research Scientist, Lichenology, Canadian Museum of Nature.

Shelley Pruss, Ph.D., Species Conservation Specialist, Natural Resources Conservation Branch, Parks Canada / Government of Canada.

Mary Sabine, Biologist, Species at Risk Program, Fish and Wildlife Branch, Department of Natural Resources, Government of New Brunswick.

Information sources

Alstrup, V. and S.N. Christensen. 2006. New records of lichens with cyanobacteria from Tanzania and Kenya. Cryptogam Mycolology 27:57 to 68.

Antoine, M. E. 2004. An Ecophysiological Approach to Quantifying Nitrogen Fixation by Lobaria oregana. Bryologist 107:82 to 87.

Armstrong, R. A. 1987. Dispersal in a population of the lichen Hypogymnia physodes. Environmentla and Experimental Botany 27:357 to 363.

Asplund, J. and Y. Gauslaa. 2008. Mollusc grazing limits growth and early development of the old forest lichen Lobaria pulmonaria in broadleaved deciduous forests. Oecologia 155:93 to 99. doi:10.1007/s00442-007-0891-z.

Asplund, J. and Y. Gauslaa. 2010. The gastropod Arion fuscus prefers cyanobacterial to green algal parts of the tripartite lichen Nephroma arcticum due to low chemical defence. Lichenologist 42:113. doi:10.1017/S0024282909990284.

Aubin, I., C. Messier and A Bouchard. 2008. Can plantations develop understorey biological and physical attributes of naturally regenerated forests? Biological Conservation 141:2461 to 2476. doi:10.1016/j.biocon.2008.07.007.

Bayne, D. personal communication 2018. Regional Biologist Western Region, Nova Scotia Department of Natural Resources, communication (July 25).

Bayne, D. pers. comm. 2019, Regional Biologist Wesstern Region, Nova Scotia Department of Natural Rsources, communication (April, 25^th)

Baur A., B. Baur and L. Fröberg. 1994. Herbivory on calcicolous lichens: different food preferences and growth rates in two co-existing land snails. Oecologia 98:313 to 319. doi:10.1007/BF00324219.

Belinchón, R, R. Yahr and C. J. Ellis. 2015. Interactions among species with contrasting dispersal modes explain distributions for epiphytic lichens. Ecography (Cop) 38:762 to 768. doi:10.1111/ecog.01258.

Bertuzzi, S. and M. Tretiach. 2013. Hydrogen sulphide inhibits PSII of lichen photobionts. Lichenolologist 45:101 to 113. doi:10.1017/S0024282912000667.

Bjerke, J.W., M. Zielke and B. Solheim. 2003. Long-term impacts of simulated climatic change on secondary metabolism, thallus structure and nitrogen fixation activity in two cyanolichens from the Arctic. New Phytolologist 159:361 to 367. doi:10.1046/j.1469-8137.2003.00812.x.

Boch, S., D. Prati and M. Fischer. 2016. Gastropods slow down succession and maintain diversity in cryptogam communities. Ecology. 97:2184 to 2191. doi:10.1002/ecy.1498.

Boch,S., D. Prati, D. Hessenmöller, E. D. Schulze and M. Fischer. 2013. Richness of lichen species, especially of threatened ones, is promoted by management methods furthering stand continuity. PLoS One 8. doi:10.1371/journal.pone.0055461.

Bowling, C. and V. Zelazny. 1992. Forest site classification in New Brunswick. Forestry Chronical 68:34 to 41.

Brinker, S.R. 2017. Discovery of Chamaenerion latifolium (L.) Holub (Onagraceae) in the Great Lakes region. Great Lakes Botany 56:3 to 9.

Buda, N.J., R.G. White, G.Kayahara, and S.F. Duckett. 2011. Silvicultural Practices for Eastern White Cedar in Boreal Ontario. Thunder Bay, ON: Ontario Ministry of Natural Resources Technical Report Report No.: 005.

Cameron, R.P. 2009. Are non-native gastropods a threat to endangered lichens? Canadian Field-Naturalist 123:169 to 171.

Carnus, J-M., J.A. Parrotta, E.G.Brockerhoff, M. Arbez, M.J. Kremer, D. Lamb, K. O’Hara and B. Walters. 2006. Planted forests and biodiversity. Journal of Forestry 104 (2):65 to 77.

Carou, S., J. Aherne, R. Ouimet, P.A. Arp, S.A. Watmough, I. DeMerchant, M. Shaw, B. Vet and V, Bouchet et al. 2008. A National Picture of Acid Deposition Critical Loads for Forest Soils in Canada: A report prepared for the CCME Acid Rain Task Group. Ottawa, ON.

Clair, T.A. , I.F. Dennis and R. Vet 2011. Water Chemistry and Dissolved Organic Carbon Trends in Lakes from Canada’s Atlantic Provinces: No Recovery from Acidification Measured after 25 Years of Lake Monitoring. Canadian Journal of Fisheries and Aquatic Science 68:663 to 674.

Clair, T.A. and A. Hindar. 2005. Liming for the mitigation of acid rain effects in freshwaters: A review of recent results. Environmental Reviews 13:91 to 128. doi:10.1139/a05-009.

Clayden, S.R. personal communication 2019. E mail communication. New Brunswick Museum 22^nd May.

Coder, K. 2000. Estimating Leaning Tree Failures. Athens Warnell School of Forest Resources Extension Publications Report No.: FOR00-13.

Cole, H. A., S.G. Newmaster, L. Lanteigne and D. Pitt. 2008. Long-term outcome of precommercial thinning on floristic diversity in north western New Brunswick, Canada. Forest - Biogeosciences 1:145 to 156. doi:10.3832/ifor0470-0010145.

Consortium of North American Lichen Herbaria. 2017. Site Records for Fuscopannaria leucosticta. [accessed Aug 31 2017]

Cornejo, C. and C. Scheidegger. 2016. Cyanobacterial gardens: The liverwort Frullania asagrayana acts as a reservoir of lichen photobionts. Environmental and Microbiology Reports 8:352 to 357. doi:10.1111/1758-2229.12386.

COSEWIC. 2002. COSEWIC assessment and status report on the Boreal Felt Lichen Erioderma pedicellatum in Canada. Ottawa, ON.

COSEWIC. 2007. COSEWIC assessment and status report on the Olive-sided Flycatcher Contopus cooperi in Canada. Ottawa, ON: Committee on the Status of Endangered Wildlife in Canada.

COSEWIC. 2008. COSEWIC Assessment and Status Report on the Canada Warbler Wilsonia canadensis. Ottawa, ON.

COSEWIC. 2009. COSEWIC assessment and status report on the Vole Ears Erioderma mollissimum in Canada. Ottawa, ON.

COSEWIC. 2010. COSEWIC assessment and status report on the Blue Felt Lichen Degelia plumbea in Canada. Ottawa, ON.

COSEWIC. 2014. COSEWIC assessment and status report on the Boreal Felt Lichen Erioderma pedicellatum Boreal population Atlantic population in Canada. Ottawa, ON.

COSEWIC. 2016. COSEWIC assessment and status report on the Wrinkled Shingle Lichen Pannaria lurida in Canada. Ottawa, ON.

Coxson, D. S. and N.M. Nadkarni . 1995. Ecological Roles of Epiphytes in Nutrient Cycles of Forest Ecosystems. In: Lowman M.D., Nadkarni N. M. and Roy J. (editors). Forest Canopies. 1st ed. Cambridge, MA, U.S.A.: Academic Press Inc. 624 p.

Dodds, W. K., D.A. Gudder and D. Mollenhauer. 1995. the Ecology of Nostoc. Journal of Phycolology 31:2 to 18. doi:10.1111/j.0022-3646.1995.00002.x.

Drost, P. 2017. No stone unturned: Biota New Brunswick uncovers new species. Fredericton, NB.

Eaton, S., and C.J. Ellis . 2014. High demographic rates of the model epiphyte Lobaria pulmonaria in an oceanic hazelwood (western Scotland). Fungal Ecology 11:60 to 70. doi:10.1016/j.funeco.2014.03.007.

ESRI Inc. 2017. ArcGIS Spatial Analyst.

Environment Canada 2018. Canadian Climate Normals and Station data

Fedrowitz, K., M. Kuusinen and T.Snäll. 2012. Metapopulation dynamics and future persistence of epiphytic cyanolichens in a European boreal forest ecosystem. Journal of Applied Ecology 49:493 to 502. doi:10.1111/j.1365-2664.2012.02113.x.

Gauslaa. Y., P. Bartemucci, and K. A. Solhaug. 2019. Forest edge-induced damage of cephalo- and cyanolichens in inland old-growth rainforest of northern British Columbia. Manuscript in submission. Canadian Journal of Forestry Research 49:434 to 439.

GBIF Secretariat. 2017. Fuscopannaria leucosticta (Tuck.) P.M.Jørg. GBIF Backbone Taxon. [accessed Oct 9 2017]

Gilliam FS. Roberts MR. 1995. Plant diversity in managed forests. Ecological Applications 5:911 to 912.

Häffner E., B. Lomský, V. Hynek, J.E.Hallgren, F.Batic and H. Pfanz H. 2001. Physiological responses of different lichens in a transplant experiment following an SO2-gradient. Water Air and Soil Pollution 131:185 to 201.

Harper, K. A., S.E. MacDonald, P.J. Burton, J. Chen, K.D. Brosofske, S.C. Saunders, E.S. Euskirchen, D. Roberts, M.S. Jaiteh and P.A.Esseen. 2005. Edge influence on forest structure and composition in fragmented landscapes. Conservervation Biology 19:768 to 782.

Hauck, M. and T. Spribille. 2005. The significance of precipitation and substrate chemistry for epiphytic lichen diversity in spruce-fir forests of the Salish Mountains, northwestern Montana. Flora Morpholology, Distribution and Functional Ecology of Plants 200:547 to 562. doi:10.1016/j.flora.2005.06.006.

Haughian, S.R., R.P.Cameron and S.R. Clayden. 2018. On the distribution and habitat of Fuscopannaria leucosticta in New Brunswick, Canada. Ecoscience (1 to 15). DOI: 10.1080/11956860.2018.1526997.

Haughian, S.R. and K.A. Frego . 2017. Does CWD mediate microclimate for epixylic vegetation in boreal forest understories? A test of the moisture-capacitor hypothesis. Forest Ecolology and Management 389:341 to 351. doi:10.1016/j.foreco.2017.01.011.

Haughian, S.R, and K.A. Harper. 2018. Clearcut edge influence on epiphytic cyanolichens in old, wet, mixedwood forests of Nova Scotia: Year 1 of the L-ACER field study. Eastern CANUSA Forestry Conference, October 18 to 20, 2018. Fredericton, NB, Canada.

Hedenås, H. and L. Ericson. 2008. Species sites at stand level cannot be understood without considering the landscape context: Cyanolichens on aspen in boreal Sweden. Biological Conservation 141:710 to 718. doi:10.1016/j.biocon.2007.12.019.

Hurlburt, D. pers.comm. 2019. Manager of Biodiversity, Nova Scotia Department of Lands and Forests, E mail correspondence, May 12^th, 2019

Hinds, J.W and P.L.Hinds. 2007. The macrolichens of New England. Buck WR, Daniel TF, editors. New York, NY, U.S.A.: New York Botanical Garden Press.

Honegger, R. 2008. Morphogenesis. In: Nash T.H. , editor. Lichen Biology. 2nd edition, Cambridge, U.K.: Cambridge University Press. Pp. 71 to 95.

Hooper, D.U. and P.M Vitousek. 1998. Effects of plant composition and diversity on nutrient cycling. Ecological Monographs 68:121 to 149.

International Joint Commission. 2016. Canada United States Air Quality Agreement: Progress Report 2016. Progress Reports.

Jørgensen, P.M. 1978. The lichen family Pannariaceae in Europe. Opera Botanica 45:1 to 123.

Jørgensen, P.M. 2000. Survey of the lichen family Pannariaceae on the American continent, North of Mexico. Bryologist 103:670 to 704.

Jørgensen, P.M. and H.J.M. Sipman. 2007. The lichen Fuscopannaria leucosticta (Tuck.) P. M. Jørg. found in the tropics. Lichenologist 39:305. doi:10.1017/S0024282907006767.

Keller, H.W., J.S. Ely, H.T. Lumbsch and S.B. Selva. 2007. Great Smoky Mountains National Park’s First Lichen Bio-Quest. Southeastern Naturalist Special Issue:89 to 98.

Knops, J.M.H., T.H. Nash and W.H. Schlesinger. 1996. The influence of epiphytic lichens on the nutrient cycling of an oak woodland. Ecological Monographs 66:159 to 179.

Knowles, R.D. , J. Pastor and D.D. Biesboer. 2006. Increased soil nitrogen associated with dinitrogen-fixing, terricolous lichens of the genus Peltigera in northern Minnesota. Oikos 114:37 to 48. doi:10.1111/j.2006.0030-1299.14382.x.

Kobylinski, A. and A. L. Fredeen. 2015. Importance of arboreal cyanolichen abundance to nitrogen cycling in sub-boreal spruce and fir forests of Central British Columbia, Canada. Forests 6:2588 to 2607. doi:10.3390/f6082588.

Lahey, W. 2018 An independent Review of Forestry Practices in Nova Scotia, Executive Summary Conclusions and Recommendations (PDF).

Larsson, P and Y. Gauslaa 2011. Rapid juvenile development in old forest lichens. Botany 89(1): 65 to 72. doi:10.1139/B10-086.

Lawrence, G. B, P.W. Hazlett, I.J. Fernandez, R Ouimet , S.W. Bailey, W.C.Shortle, K.T. Smith and M.R. Antidormi. 2015. Declining acidic deposition begins reversal of forest-soil acidification in the Northeastern U.S. and Eastern Canada. Environmental Science & Technology 49(22): 13103 to 13111. DOI: 10.1021/acs.est.5b02904.

Lawrey, J.D., A.P.Torzilli and V. Chandhoke. 1999. Destruction of lichen chemical defenses by a fungal pathogen. American Journal of Botan 86:184 to 189. doi:10.2307/2656935.

Lemmen, D.S., F.J. Warren, T.S. James and C.S,L. Mercer-Clarke ( editors) 2016. Canada’s Marine Coasts in a Changing Climate; Government of Canada, Ottawa, ON, 274p.

Lendemer, J.C. and E.A.Tripp. 2008. Contributions to the lichen flora of North Carolina: A preliminary checklist of the lichens of Gorges State Park. Bryologist 111:57 to 67.

Lewis, C.J. and S.R. Brinker SR. 2017. Notes on new and interesting lichens from Ontario, Canada – III. Opusc Philolichenum. 16:153 to 187.

Lönnell, N., K. Hylander, B.G. Jonsson and S. Sundberg. 2012. The fate of the missing spores - patterns of realized dispersal beyond the closest vicinity of a sporulating moss. PLoS One. 7. doi:10.1371/journal.pone.0041987.

Loo, J.A. and N. Ives. 2003. The Acadian forest: historical condition and human impacts. Forestry Chronical 79:462 to 474. doi:10.5558/tfc79462-3.

Marini, L., J. Nascimbene and P.L. Nimis. 2011. Large-scale patterns of epiphytic lichen species richness: Photobiont-dependent response to climate and forest structure. Science of the Total Environment 409:4381 to 4386. doi:10.1016/j.scitotenv.2011.07.010.

McCarthy, P.M. and J.A. Healy. 1978. Field and study notes: dispersal of lichen propagules by slugs. Lichenologist 10:131 to 134.

McCLearn, M. 2018. Rising seas and climate change. Globe and Mail. May 14^th.

Moss, M. and L. Hermanutz. 2010. Monitoring the small and slimy - Protected areas should be monitoring native and non-native slugs (Mollusca: Gastropoda). Natural Areas Journal 30:322 to 327.

Mosseler, A., I.D. Thompson and B.A. Pendrel. 2003. Overview of old-growth forests in Canada from a science perspective. Environmental Reviews 11:S1 to S7. doi:10.1139/a03-018.

Nash, T.H. 1996. Photosynthesis, respiration, productivity, and growth. In: Nash T.H., editor. Lichen Biology. Cambridge, U.K.: Cambridge University Press. Pp. 88 to 120.

Nash, T.H.. 2008. Nitrogen, its metabolism and potential contribution to ecosystems. In: Lichen Biology. Cambridge, U.K.: Cambridge University Press Pp. 218 to 235.

Nieboer, E, J.D. MacFarlane and D.H.S. Richardson. 1984. Modifications of plant cell buffering capacities by gaseous air pollutants. In: M. Koziol & F.R. Whatley (editors). Gaseous air pollutants and plant metabolism. London, U.K.: Butterworths. Pp. 313 to 330.

Nova Scotia Department of Environment. 2018. Identifying lichen rich areas in Nova Scotia (Draft #180215_B). Nova Scotia Department of Environment, Halifax, NS, Canada.

Nova Scotia Department of Natural Resources 2018, At risk Lichens–Special Management Practices (PDF) May 23, 10p.

Nova Scotia Government 2919. Response To the Independent Review of Forest Practices in Nova Scotia Ecological Forestry Implementation - March 26, 2019 update.

Nova Scotia Department of Natural Resources. 2017. Registry of Buyers Annual Reports (2010 to 2017). Halifax, NS, Canada.

Nova Scotia Department of Natural Resources. 2018. At risk lichens – Special Management Practices. Nova Scotia Department of Natural Resources, Kentville, NS, Canada.

Öckinger, E.and S.G. Nilsson. 2010. Local population extinction and vitality of an epiphytic lichen in fragmented old-growth forest. Ecology 91:2100 to 2109.

Oldham, M.J. and S.R. Brinker. 2011. Additions to the vascular flora of Ontario, Canada, from the Sutton Ridges, Hudson Bay Lowland ecoregion. Canadian Field-Naturalist 125:241 to 247.

Pearson, K., R.P. Cameron and R.T. McMullin. 2018. Habitat associations and distribution model for Fuscopannaria leucosticta (Tuck.) P.M. Jørg. in Nova Scotia, Canada. Lichenologist 50:487 to 597. doi:10.1017/S0024282918000300.

Perlmutter, G.B. 2006. Lichen Inventory of the North Carolina Piedmont. Castanea 71:282 to 294.

Pickett, S.T.A. and P.S. White. 1985. The ecology of natural disturbance and patch dynamics. London, U.K.: Academic Press Inc.

Ponder, W.F., G.A.Carter, P. Flemons and R.R. Chapman. 2001. Evaluation of museum collection data for use in biodiversity assessment. Conservation Biology 15:648 to 657. doi:10.1046/j.1523-1739.2001.015003648.x.

Porté, A., F. Huard and P. Dreyfus. 2004. Microclimate beneath pine plantation, semi-mature pine plantation and mixed broadleaved-pine forest. Agricultural and forest Meteorolology 126:175 to 182. doi:10.1016/j.agrformet.2004.06.001.

Province of New Brunswick. 2014. A strategy for Crown lands forest management: putting our resources to work. Fredericton, NB.

Province of New Brunswick 2018. Forest Management Strategy (PDF). Fredericton, N.B.

Racey, G.D., A.G.Harris, J.K. Jeglum, R.F. Foster and G.M. Wickware. 1996. Terrestrial and wetland ecosites of northwestern Ontario (PDF). NWST Field Guide FG-02.

Richardson, D.H.S. and R.P.Cameron. Cyanolichens: Their response to pollution and possible management strategies for their consvervation in northeastern North America. Northeastern Naturalist 11:1 to 22.

Rikkinen, J. 2015. Cyanolichens. Biodiversity and Conservation 24:973 to 993. doi:10.1007/s10531-015-0906-8.

Romero-Lankao, P., J. Smith, D. Davidson, N.S. Diffenbaugh, P. Kinney, P. Kirshen , P. Kovacs, L.V. Ruiz, W. Anderegg, J. Carr, et al. 2014 Climate Change: Impacts, Adaptation and Vulnerability - Contributions of the Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, U.K.: Cambridge University Press. Pp. 1439 to 1498.

Ross-Davis, A.L. and K.A. Frego. 2002. Comparison of plantations and naturally regenerated clearcuts in the Acadian Forest: forest floor bryophyte community and habitat features. Canadian Journal of Botany 80:21 to 33. doi:10.1139/b01-129.

Saad, C., Y. Boulanger, M. Beaudet, P. Gachon, J.C. Ruel and S. Gauthier. 2017. Potential impact of climate change on the risk of windthrow in eastern Canada’s forests. Climate Change 143:487 to 501. doi:10.1007/s10584-017-1995-z.

Sabine, M. pers. comm. (2019) Biologist, Species At Risk, Forest Planning & Stewardship Branch, New Brunswick. E mail Correspondance, 13^th May, 2019.

Salafsky, N., D. Salzer, A.J. Stattersfield, C. Hilton-Taylor, R. Neugarten, S.H.M. Butchart, B. Collen, N. Cox, L.L. Master, S. O’Connor, and D. Wilkie. 2008. A standard lexicon for biodiversity conservation: unified classifications of threats and actions. Conservation Biology 22:897 to 911.

Spribille, T. 2009. Fuscopannaria leucosticta (Tuck.) P.M. Jørg. rediscovered in Europe. Lichenologist 41:209. doi:10.1017/S0024282909007907.

Stewart, B.J., T. Neily, E.J. Quigley, A.P. Duke and L.K. Benjamin . 2003. Selected Nova Scotia old-growth forests: Age, ecology, structure, scoring. Forestry Chronical 79:632 to 644. doi:10.5558/tfc79632-3.

Veinotte, C.B. Freedman, W.S.G. Maass and F. Kirstein. 2003. Comparison of the ground vegetation in spruce plantations and natural forest in the greater fundy ecosystem, New Brunswick. Canadian Field-Naturalist 117:531 to 540.

Wang, X.L. 2006. Climatology and trends in some adverse and fair weather conditions in Canada, 1953 to 2004. Journal of Geophysical Research 111, D09105, doi:10.1029/2005JD006155.

Zackrisson, O. , T.H. Deluca, F. Gentili, A. Sellstedt and A. Jäderlund. 2009. Nitrogen fixation in mixed Hylocomium splendens moss communities. Oecologia 160:309 to 319. doi:10.1007/s00442-009-1299-8

Biographical summary of report writers

Sean Haughian, PhD, has studied cryptogam ecology and biogeography for over a decade in Canada. His graduate studies focused on the intersection of cryptogam substratum ecology and disturbance in forest ecosystems (Haughian 2010, 2017), giving him experience in physiological ecology and habitat modelling for climate-sensitive species. He is a graduate of the University of Alberta (BSc, 2005), University of Northern BC (MSc, 2011), and the University of New Brunswick (PhD, defended on November 9^th, 2016). He has also worked with Ducks Unlimited (2002 to 2003), the Alberta Biodiversity Monitoring Initiative (2004 to 2005), Wildlife Infometrics Inc. (2008), and the Atlantic Conservation Data Centre (2015). Sean has authored peer-refereed articles, given many public and academic presentations, and taught botany, ecology, and other biology courses at the University of New Brunswick (UNB). He is currently a Research Associate with the New Brunswick Museum (NBM) and a Mitacs Elevate Postdoctoral Fellow at Saint Mary’s University.

Stephen R. Clayden, PhD, has studied lichen ecology, systematics, and biogeography in Atlantic Canada (and elsewhere) for over 30 years, and has authored a number of works on rare or endangered lichens (Goward et al. 1998, Cameron et al. 2011). As curator of the NBM herbarium, Stephen initiated a collection of lichens that has grown to include more than 35,000 specimens, has overseen digitization of the data from these collections, and has enabled public access to these data via the Consortium of North American Lichen Herbaria. Stephen was responsible for discovering seven of the first eight sites of F. leucosticta in New Brunswick. He is a graduate of Mount Allison University (BSc, 1978), the Université de Montréal (MSc 1982), and the University of London, UK (PhD, 2004). Since 1987, he has been Research Curator of Botany and Mycology at the NBM in Saint John, has authored over three dozen refereed articles and has given numerous public and academic presentations. Stephen teaches lichen identification and ecology at the Humboldt Field Research Institute (HFRI; Maine, USA), and is an Adjunct Professor at UNB. He is also a member of the Scientific Advisory Committee on Protected Natural Areas in New Brunswick, and has contributed to conservation organizations such as COSEWIC, the New Brunswick Wildlife Council, and the Nature Trust of New Brunswick.

Robert Cameron, MSc, has studied environmental planning, and the conservation and biogeography of lichens for over 20 years in Nova Scotia, and has authored many publications on them. He has developed several predictive species distribution models for rare lichens in Atlantic Canada (Cameron et al. 2011). Robert is a graduate of UNB (BSc, 1987), and Acadia University (MSc, 1998). Since 2002, he has been an ecologist with the Nova Scotia Department of Environment in Halifax, Nova Scotia. Robert has worked extensively in both the public and private sector, including the New Brunswick Department of Natural Resources (1987), Cameron Forestry Consulting (1992 to 2000), and the B.C. Ministry of Forests (2000 to 2002), among others. He has authored more than 30 peer-reviewed articles, has given many guest lectures and academic presentations, and taught at several post-secondary institutions, including Dalhousie University, where he is currently an Adjunct. Robert has contributed to advisory bodies such as COSEWIC and the Nova Scotia Lichen Recovery Team.

Frances Anderson, MLS, has studied lichens for over 12 years in northeastern North America, and is an authority on their biogeography and identification. She has contributed to several COSEWIC status reports for lichens, and two extensive works on their identification and biogeography (Anderson 2014, McMullin and Anderson 2015). Frances is a graduate of Boston University (BA, 1969), and Dalhousie (MLS, 1979). Frances was a Research Associate at the Nova Scotia Museum from 2006 to 2014 and has taught and consulted as an independent with numerous academic, governmental, and private organizations in eastern Canada. Her lichenological training includes many short-courses on lichen identification and ecology from the HFRI.

Samuel R. Brinker, BES, is a provincial botanist with the Natural Heritage Information Centre in the Science and Research Branch of the Ontario Ministry of Natural Resources and Forestry (MNRF). For the last 10 years in this role he has conducted province-wide or regional assessments of vascular plants and lichens, with particular emphasis on documenting the distribution and abundance of rare, threatened and endangered species. He also assists provincial and federal partners with various monitoring and focused inventories, such as vegetation mapping with Parks Canada in Aulavik and Torngat Mountains National Parks. He has previously written COSEWIC status reports on 4 vascular plants and 2 lichens. Prior to this, Sam held a number of positions with the MNRF after spending several years as a consulting botanist. Sam received a Bachelor of Environmental Studies (BES) from the University of Waterloo.

Collections examined

All the known collections of Fuscopannaria leucosticta from Canada that could be located by herbarium staff at the holding institutions were examined. Accession numbers are provided in our field summary report (Appendix 4) along with recent observation data.

Appendix 1. Threats calculator for Fuscopannaria leucosticta

Threats assessment worksheet

Species or ecosystem scientific name:

Fuscopannaria leucosticta White-rimmed Shingle Lichen

Element ID:

Not applicable

Elcode:

Not applicable

Date:

27/02/2018

Assessor(s):

David Richardson (co-chair), Dwayne Lepitzki (moderator), Sean Haughian (report writer), Frances Anderson (report writer), Samuel Brinker (report writer), Robert Cameron (report writer), Stephen Clayden (report writer), Julie McKnight, Mary Sabine (New Brunswick)

References:

Draft calculator (8 Nov 2017) provided accompanying draft Status Report

Assigned overall threat impact:

BC = High - Medium

Impact adjustment reasons:

Approximately 49% of known colonies are not protected by natural areas or parks, and may therefore be subjected to wood-harvesting activities.

Overall threat comments:

See comments under Logging and wood harvest. Generation time 5 to 22 years; 3 gens = 15 to 66 years

Classification of threats adopted from IUCN-CMP, Salafsky et al. (2008).

Appendix 2: Method for estimating population sizes in each province

In this model, potentially suitable habitat was isolated from forest inventory GIS layers polygons by selecting specific characteristics that were chosen differently for Nova Scotia and New Brunswick and a separate approach was used for Ontario.

Population size = [Σ(ENT x PO)] x OR

The population size is the sum of the estimated number of thalli (ENT) x the probability of occurrence (PO) for each polygon within a province, which is then multiplied by an occupancy ratio from field data (Inputs and methods below).

Polygons:

1. New Brunswick and Nova Scotia Polygons for kriging were selected based on
   1. old and unmanaged forests,
   2. forests with Eastern White Cedar in New Brunswick, and Red Maple in Nova Scotia.
2. cdd NS polygons were selected based on the additional characteristics of wet, with water table depth of 0 to 2 m, and within 25 m of a forested wetland
3. For New Brunswick, there were 6666 polygons with an average size of 78 ± 108 ha.
4. For Nova Scotia, there were 62,602 polygons with an average size of 56 ± 62 ha.

ENT:

The number of thalli surveyed in observed 50 x 50 m cells provides the input for kriging. In general, a 50 x 50 m cell is equivalent to a sampling site.

The ENT is estimated in two steps:

1. The kriging method estimates the number of thalli per 50 x 50 m cell.
2. The ENT (Expected number of thalli) for each polygon is the average number of thalli / cell.

PO:

Probability of occurrence varies from 0 to 1.

The PO assigned to a given polygon was the average PO from all the cells in that polygon.

PO is based on an evaluation of the habitat’s ability to support the lichen using:

For Nova Scotia:

1. Depth to water table
2. Distance to the coast
3. Mean annual temperature
4. Mean annual precipitation

For New Brunswick:

1. Absence of disturbance
2. Cedar in the canopy
3. Mean annual rainfall
4. Degree days

ENT x PO:

Estimates the number of thalli that are expected to occur, under ideal conditions, in each New Brunswick and Nova Scotia polygon (suitable habitat patch), based on sampling and the PO covariates.

OR:

OR is the occupancy ratio of promising sites from recent survey efforts in New Brunswick and Nova Scotia. It is a correction required because F.l. does not occupy all suitable habitat patches. The occupancy ratio (OR) of promising sites from recent survey efforts in each province (13/22 for New Brunswick, and 37/159 for Nova Scotia).

Because the inclusion of fractions of thalli in the projection seemed unrealistic, only polygons for which (ENT x PO) >1 were used to calculate the total population size. To provide a range of population sizes that accurately reflected the uncertainty, based on the variability in site data, the standard deviation in PO and ENT were quantified for each polygon, and additional estimates were made using the mean PO and ENT plus or minus 1 SD.

This function was tested on a subset of the data from New Brunswick that included observed and predicted abundances for occurrences with ground-truthed abundance (N=199). The fit was poor (R² = 0.14), due to high variability in the abundance data, but the relationship was significant (t = 7.58, P < 0.001).

Using the method outlined above, it was estimated that the estimated approximate size of the population in New Brunswick was 4,315 (+/-1SD = 2,474 to 6,206) and for Nova Scotia 4,311 (+/-1SD = 3,196 to 5,599).

For Ontario, the numbers were calculated by considering the three forest management units (FMU).

Lakehead Forest FMUs (Forest management units)

• 762,170 ha total size.
• Area of old-growth cedar swamp (>120 years old) in FMU: ~1911 ha (or 0.2% of total FMU).
• Area of old-growth cedar swamp within protected areas not accessible to logging activities: ~454 ha (~23%).
• Total number of thalli counted in FMU: 36.
• Number of potential thalli (upper limit) assuming every old-growth cedar swamp polygon identified is occupied: 764 (at 0.4 thalli per ha out of the 1911 ha total).
• If we assume that 25% of the polygons are occupied: 191 thalli.
• If we assume that 10% of the polygons are occupied: 76 thalli.

Black Spruce Forest FMU

• 1.3 million ha total size
• Area of old-growth cedar swamp (>120 years old) in FMU: ~1781 ha
• Area of old-growth cedar swamp in protected areas not accessible to logging activities: ~70 ha (~4%).
• Total number of thalli counted in FMU: 39.
• Number of potential thalli (upper limit) assuming every old-growth cedar swamp polygon identified is occupied: 712 (at 0.4 thalli per ha out of the 1781 ha total).
• If we assume that 25% of all the polygons are occupied: 445 thalli.
• If we assume that 10% of all the polygons are occupied: 71 thalli.

Quetico Provincial Park

• 476,000 ha total size
• Area of old-growth cedar swamp (>120 years old) in FMU: ~31 ha.
• Area of old-growth cedar swamp in protected areas not accessible to logging activities: ~31 ha (100%).
• Total number of thalli counted in FMU: 2.
• Number of potential thalli (upper limit) assuming every old-growth cedar swamp polygon identified is occupied: 12 (at 0.4 thalli per ha out of the 31 ha total).
• If we assume that 25% of all the polygons are occupied: 3 thalli.
• If we assume that 10% of the all the polygons are occupied: 1 thallus.

Assumptions made:

• Fuscopannaria leucosticta occurs at roughly 0.4 thalli per hectare in Ontario where it has been found.
• Old-growth cedar swamp identified in the analysis = treed stands with >70% cedar in the canopy, are >120 years of age, and are typed as wet (organic soil or saturated mineral soil that is circumneutral). Therefore this total excludes all upland cedar stands and those not likely to be classed as wetlands.
• The Forest Resource Inventory data used was accurate (which we know is not necessarily/always the case).

The amount of the amount of old-growth cedar swamp was identified in the 3 occupied FMUs (~3,723 ha out of ~2.5 million ha).

For this subpopulation, assuming ~0.4 thalli per hectare, the upper limit of the population would be 1,488 thalli. This assumes that every single identified old-growth cedar swamp polygon was occupied in all three 3 FMUs. This is most unlikely and a more realistic assumption based on observations elsewhere is that that 25% of these polygons are colonized at 0.4 thalli per hectare which results in a total estimated population of 639 thalli for Ontario.

Appendix 3: Method for estimating future population sizes and declines

The following model was used to project the number of thalli at all sampled sites over three generations by 6-year intervals.

Population decline model:

${\displaystyle \mathrm{P_n,t}=\sum _{\mathrm{<mi>i=1</mi>}}^n\left[\mathrm{P_i,2017}– \mathrm{l_i}–\; 0.0093(t\; –\; 2017)\; (\mathrm{P_i,2017})\right]}$

Definitions:

P_n,t the number of thalli projected to occur at all sampled sites in year t. These projected numbers of thalli are used to estimate the future population decline in mature individuals.

P_i,2017 = number of thalli at each site in 2017.

l_i = number of thalli expected to be lost from sites that have been recently disturbed or that are expected to be disturbed.

Information on these sites is provided in Table 3. Under the column "Trend" (next 3 generations), include:

1. Sites where logging is expected, and all thalli will be lost within 2 to 6-year time frame
2. Thalli on residual trees in recently logged stands will die within 1 to 3 years

For example, if:

P_i,2017 = 20 and the site satisfies either 1 or 2 above l_i = 20, and P_i,2017 - l_i = 0.

The percentage of sites lost between 2007 and 2017 across Canada is 9.3%.and is used as a proxy for decline.

Assumptions: Decline rate for each site:

1. Future losses will occur at the same rate as 2007 to 2017 losses
2. Losses were estimated assuming a 0.93% (9.3%/10) annual reduction in thalli for the next three generations (36 years) in all provinces

The decline after 6 years (0.5 generation) as a result of initial losses is 21%. Once these initial losses are accounted for, the decline over the next 2.5 generations is 30%. Thus, the model above projects a reduction in the number of mature individuals over three generations of 45% (Figure 15).

A consequence of the 0.0093(P_i,2017) model term is that the number of thalli projected to be lost each year is constant and the decline will be a straight line over time. Hence, even if l_i = 0 at all sites, the decline over three generations will be 33% and the decline over the last 2.5 generations at each site will be 30% regardless of the value of P_i,2017.

The 0.0093(P_i,2017) model term differs from the compound interest model that is normally used by COSEWIC when estimating population declines. Back-calculating the 9.3% decline, from 2007 to 2017, to a compound interest rate provides an annual decline rate estimate of 0.0097. The three-generation decline estimates will differ between these two methods. For example, even if l_i = 0 at all sites, the decline, using this compound interest rate, is slightly curvilinear and 30% over three generations. In this case, because the annual rate is relatively low, the selection of a constant instead of a compound interest decline rate does not affect conclusions regarding designation status. In addition, the minimum population decline over three generations, ignoring initial losses, l_i = 0 at all sites, is 30%. However, because of initial losses, a decline over three generations >30% is well supported.

Note that based on field evidence (for example, nearby clearcuts, new logging roads, or presence of cut-boundary tape), sites were classified as “likely stable”, “likely declining”, “declining”, or “extirpated” for the last 10 years (Table 3). Additional columns indicate whether the site was protected or not (“Habitat protection?”) and what the likely trend would be in the future, based on the combination of recent disturbance on or adjacent to the site (=declining), the existence of habitat protection (stable), or the absence of habitat protection, but with no obvious active threats in the vicinity (at risk). A single rate of change was applied to all sites, trees, and thalli, regardless of their protection status, after the ‘inferred’ losses were accounted for. This was considered to be reasonable primarily based on simplicity and statistical considerations.

Based on the number of lost sites between 2007 and 2017 (9 sites = 9.3%), the annual loss rate was estimated to be 0.93% for the entire population. This annual loss rate was multiplied by the number of years passed for each time column and subtracted from the observed number of sites (as a proportion of a single whole), trees, or thalli in 2017 for each site. The sum of the remaining sites, trees, and thalli were then calculated for each province, and for the Canadian population as a whole to generate the numbers used in the Technical Summary of this report.

Appendix 4: Field summary data