Barrens Willow (Salix jejuna Fernald) recovery strategy: chapter 4
REFERENCES CITED
Anions, M.F.E. 2000. COSEWIC Status Report on Barrens Willow, Salix jejuna. Committee on the Status of Endangered Wildlife in Canada. 24 pp. (Unpublished report)
Argus, G.W. 1997. Infrageneric classification of Salix L. in the New World. Systematic Botany Monographs. 52: 1-121.
Argus, G.W. 2003. Personal communication to Nathalie Djan-Chékar.
Bouchard, A, S. Hay, L. Brouillet, M. Jean and I. Saucier. 1991. The rare vascular plants of the Island of Newfoundland. Syllogeus No. 65. Canadian Museum of Nature, Ottawa.
Hermanutz, L., H. Mann, M.F.E. Anions, D. Ballam, T. Bell, J. Brazil, N. Djan-Chékar, G. Gibbons, J. Maunder, S.J. Meades, N. Smith and G. Yetman. 2002. National Recovery Plan for Long’s Braya (Braya longii Fernald) and Fernald’s Braya (Braya fernaldii Abbe). National Recovery Plan No. 23. Recovery of Nationally Endangered Wildlife (RENEW). Ottawa, Ontario. 33 pp.
Keith, D. A. 1998. An evaluation and modification of World Conservation Union Red List criteria for classification of extinction risk in vascular plants. Conservation Biology 12(5): 1076-1090.
Rabinowitz, D. 1981. Seven forms of rarity. Pages 205-217 in H. Synge, editor. The biological aspects of rare plant conservation. John Wiley and Sons, Chichester, United Kingdom.
Annex 1. Procedure for determining Critical Habitat for BarrensWillow
Compiled by Braya Recovery Team, May 25, 2005.
· Mandated under Section 28, Endangered Species Act (SNL2001 Chapter E - 10.0)
· Data used to prepare these maps are based on records from the "Rare plant database" housed within the IFWD and observational records from Recovery Team members and scientists, for a total of over 27,000 observational records that have been geospatially referenced, with 1 in 5 verified.
· Maps for all species include both historical and recent records, except for those historical records from which locations cannot be verified. These records have a Locational Accuracy Level of 2 and 1, respectively (Level 1=10m and Level 2=100m).
· Potential habitat within the Limestone Barrens for each species was delineated from aerial photographs. [Limestone barrens are defined as limestone areas with vegetation cover less than 10 cm in height over thin discontinuous sediment showing signs of frost action (for example, frost boils or sorted circles)].
· Once potential habitats were field checked, they were designated as either suitable habitat or unsuitable habit. Suitable habitats were further surveyed for species presence. If the habitat has the species present, it is automatically designated as Critical Habitat.
· Those potential habitat areas that remain to be field-checked retain their original designation. Future site surveys will follow the above protocol. See Appendix 1 for flow diagram.
· Critical habitat was delineated separately for each species, based on their endangerment and biology.
· The spatial extent of each habitat type was mapped using a central point and a maximum radius to inscribe a circle that encompassed the entire habitat. Parts of the circle that clearly are not suitable habitat (e.g. water bodies, forest and other land cover types that appear as mapped layers within our GIS database) were deleted.
Barrens Willow (Salix jejuna)
Barrens Willow has an intermediate distribution compared with the two braya species, from Eddies Cove South to Cape Norman, approx. 40 km. In contrast to braya, it does not have a long-lived seedbank, therefore it can be assumed that if there are no plants currently growing at a site that it is unlikely that they will in the near future. Therefore suitable substrates with no plants present have been designated as "Sensitive Wildlife Areas".
1. All suitable habitats with willow present have been designated as "Critical habitat".
2. All sites with suitable habitats that are not presently occupied, as well as those sites of potential suitability have been designated as "Sensitive Wildlife Areas".
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