Northern spotted owl (Strix occidentalis caurina) recovery strategy: chapter 24
Appendix 2
Preliminary List of Research Topics
| Broad Topics | Information Gaps for Decision Process | Specific Research Topicsa | Type of Studyb |
|---|---|---|---|
| POPULATION | |||
| Demography / trends | |||
| Range | Distribution relative to known range as index of health | Inventory (appropriately designed) | |
| Pattern of distribution in the landscape at different spatial scales, e.g., international and regional (metapopulations, U.S. comparison; subpopulations for local) | Assess existing information / literature, and database gathering | ||
| Abundance | Index of number of animals (animals or habitat [ha] over time) | Inventory and research | |
| Quality of population | Proportion of breeders and non-breeders, and age-specific issues | ||
| Population parameters | Survivorship, natality, immigration/emigration | ||
| Dispersal distances | |||
| Genetic profiling | |||
| Measure of variability | Relative to southern populations | ||
| Relative to ecosystem types | |||
| Identification of individuals | Population tool to track lineage | ||
| Population tool to estimate population size | |||
| Population modeling / trends | |||
| Population viability | Minimum number of breeders and distribution to sustain population over time | ||
| Minimum spatial distribution of breeders | |||
| Population projections for management decisions | |||
| HABITAT | |||
| Features of habitat (topography, vegetation, forest structure) | |||
| Nesting habitat | Describe nest trees | ||
| Describe nest patches (immediate proximity to nest) | |||
| Describe nest stands (area of similar habitat type immediately surrounding the nest patch) | |||
| What is the availability of type A and B suitable habitats, and within-stand variation of these habitats? | |||
| Home range (nesting / foraging) | Describe area used/selected during breeding period (area most used by adults [male] while young in nest) | ||
| Describe post-fledging area used (i.e., before juvenile dispersal) | |||
| Describe overwintering area used (i.e., after young disperse) | |||
| What area of habitat must be suitable in a home range (e.g., 67%) and how should it be distributed? | |||
| Dispersal habitat | |||
| Habitat-specific survivorship | Do SPOW juveniles have higher survivorship in some habitat types? | ||
| Selection of habitat | What habitats are selected by juveniles for dispersal? | ||
| Barriers | Are young forests, roads, lakes, ridges, etc., barriers to juvenile dispersal? | ||
| Modeling habitat | |||
| Suitability / capability | Amount and availability over time at different population levels | ||
| Change in habitat availability over time with natural disturbance (fire) | |||
| Connectivity of habitat | |||
| Fragmentation (patch size, distribution, and connectivity) | |||
| PREY | |||
| Population | |||
| Abundance and distribution | Availability of prey relative to different spatial criteria (e.g., broad ecosystem, stand/forest type, geographic region, and SPOW habitat) | ||
| Is prey availability limiting SPOW survival? | |||
| Does the importance of flying squirrels and bushy-tailed wood rats in diet differ by ecosystem? | |||
| Population trends | Relative to weather, food availability | ||
| Ecology of prey | Prey habitat | ||
| Prey breeding requirements | |||
| Prey foraging requirements | |||
| PREDATORS / COMPETITORS (niche overlap) | |||
| Barred Owl (BDOW) | |||
| Population | Trends in BDOW population | ||
| How does adult and juvenile survivorship and dispersal for BDOW differ from SPOW? | |||
| Do BDOW breed with SPOW? Under what conditions? | |||
| Habitat | Do BDOW select wetter ecosystems (thus distribute differently in the landscape) than SPOW? | ||
| What are features in nesting and home range habitat of BDOW? How do they compare to SPOW? | |||
| Do BDOW move seasonally and does this change how they might overlap SPOW habitat | |||
| What is home range size of BDOW | |||
| What habitats do BDOW select for foraging in the landscape? Does they differ by ecosystem, or overlap with SPOW habitat requirements? | |||
| Does the BDOW population now saturate available habitat? | |||
| Prey | What are prey of BDOW? How do relative proportions in the diet compare to those reported for SPOW? | ||
| Behaviour | Does BDOW behaviour change when overlapping home ranges of SPOW? | ||
| Great Horned Owl (GHOW) | |||
| Population | What is the density of GHOW in coastal ecosystems? | ||
| Habitat | How are GHOW distributed in the landscape compared to SPOW? | ||
| Where do GHOW forage and does this present high risk to SPOW? | |||
| Prey | What is diet of GHOW? | ||
| Other predators | |||
| Type | What are other potential predators of SPOW? | ||
| Habitat | What habitats do these predators generally forage within? | ||
| HABITAT ENHANCEMENT | |||
| Foreststructure | |||
| Stand conversion | Can unsuitable habitats for breeding and/or foraging be converted to suitable within home ranges? | ||
| Recruitment of younger stands | Can stand development be accelerated so suitable stands are grown in less than average years? | ||
| Can stand structure (e.g., snags, vertical and horizontal complexity, large branches) be created? If so, how long does this take? | |||
| Landscape connectivity | Can stands be enhanced to provide connectivity for dispersal? | ||
| Prey | |||
| Abundance | Can abundance or density of prey be increased using alternative systems to enhance prey forage or nesting/denning habitat? | ||
| HABITAT MAINTENANCE | |||
| Foreststructure | |||
| Stand-level operations | Can alternative silvicultural systems be applied that do not reduce habitat quality short term/long term? | ||
| Landscape patterns | Can landscapes be altered while maintaining dispersal habitat? | ||
| Prey | |||
| Abundance | Will retention of legacy stands help maintain prey abundance when silvicultural systems are applied to adjacent stands? | ||
aStudy questions.
bFor example, inventory, monitoring, research, or adaptive management.
Page details
- Date modified: