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Selkirk Population Should Not be Listed. Jillian Boyd Nathan Lester Andrew Jakovac. Woodland Caribou ( Rangifer tarandus caribou ). Height: 4 feet tall at the shoulder Length: 6 feet Weight: 250-700 pounds Lifespan: 10-15 years in the wild Diet: Ground and tree lichens
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Selkirk Population Should Not be Listed Jillian Boyd Nathan Lester Andrew Jakovac
Woodland Caribou (Rangifertarandus caribou) • Height: 4 feet tall at the shoulder • Length: 6 feet • Weight: 250-700 pounds • Lifespan: 10-15 years in the wild • Diet: Ground and tree lichens • Shrubs, grasses, and willows
Population • Seven subspecies of caribou • Two subspecies in the United States: • Barren ground caribou (Rangifertarandusgranti) • Woodland caribou (Rangifertarandus caribou) • Two ecotypes: • Mountain woodland caribou • Northern woodland caribou • International Selkirk population • Approximately 46 individuals
Distribution and Abundance • Historically, woodland caribou were distributed throughout much of Canada and the northern United States • Extirpated from New England by 1916 and the Great Lakes by 1940 • On January 14, 1983, the International Selkirk population was listed as endangered. • Approximately 25 individuals
Recovery Plan • A recovery plan was developed in 1985 • Objectives: • Securing and improving habitat • Addressing the impacts of road-related mortalities • Reducing the impacts of timber management • Reducing or eliminating the impacts of recreational activities
Augmentation Attempts • 1986: International Mountain Caribou Technical Committee (IMCTC) • 1987: 24 individuals • 1988: 24 individuals • 1990: 12 individuals • 1996: Washington Department of Fish and Wildlife and the U.S. Fish and Wildlife Service • 1996: 19 individuals • 1997: 13 individuals • 1998: 11 individuals
Changes in Habitat Logging of old growth forests Removal of primary winter food source: lichen Requires growth at least 80 years old that supports large amounts of arboreal lichens
Effects of Logging on the ecosystem Increase in browse Leads to an increase in White-tailed deer (Odocoileus virginianus)and Moose (aces aces) This has led to an increase in Cougars (Puma concolor) and Wolves (Canis lupus)
Effects of Logging on the ecosystem Logging roads Become trails for caribou predators Mountain Caribou need deep snow without trails in winter
Predator control Late 1990s Cougar population boom Wolf populations increasing throughout northern Idaho and northeastern Washington Better predator control is needed to help increase the Selkirk Mountain Caribou population (Zager, P. et al.)
Roads and Mountain Caribou mortality 4 road mortalities in2009 Wildlife friendly over or under passes could help address this issue Long term effects of climate change on habitat Shifting habitat north (historic habitat reached the salmon river)(Federal register-IDFG) Possible decrease in future snowpack levels Potential loss of alpine areas
Recreation Snowmobiling has negative impacts (Federal register-IDFG) Packed trails in snow Potential for stressing caribou Proposals to close off thousands of acres to snowmobiling and ATV use Possibly heli-skiing and snowcat skiing could be prohibited
Recent habitat proposal USFWS proposed designation of 375,562 acres of critical habitat in northeastern WA and northern ID This could lead to restrictions on logging, fire-control, and recreational use Source of controversy
What is needed for habitat change? A complete change of the ecosystem Old growth forests are necessary for Mountain Caribou populations to survive Conversion to old growth forests takes a very long time Benefits of habitat change on Mountain Caribou populations will not be seen for at least 50 years 100 years of habitat restoration needed for caribou to thrive again (Zager, P. et al.)
Some possible points of controversy Loss of recreation Costs to logging Long-term decline in White-tailed deer and Moose populations Increase in predator control Benefits of habitat change require long term commitment and patience
Population Analysis • Minimum Viable Population (MVP) is the smallest possible size at which a biological population can exist without facing extinction from natural disasters or demographic, environmental, and/or genetic stochasticity(Gilpin and Soulé, 1986) • 50: 500 rule • Selkirk population is estimated below 50 by all sources. Most recent count's have shown the population number at 46. • The Selkirk are only geographically distinct from the other populations of mountain woodland caribou. • All distinct populations of woodland caribou found in the world are only separated by geographic barriers.
Genetic Restrictions • Geographic genetic bottleneck • Reduce ability to adapt to new selective pressures, such as climatic change or shift in available resources • Genetic drift can eliminate alleles that could have been positively selected on by the habitat environment • With reduced allelic variation, adaptations to climate and habitat change are restricted and when those changes are present within a small population it increases the risk of extinction significantly
Ecosystem Translocation • Boreal forest • Human disturbance • Climate change
Mountain Woodland Caribou of British Columbia Mountain woodland Caribou primarily reside within British Columbia as shown in the map. Population estimates for mountain woodland caribou within BC range from 2354-1905 based on different estimation and sampling procedures. Local populations of mountain caribou and revised subpopulation delineation by Wittmer (2004).
Conservation Options • Concentration of efforts focusing on Canadian populations • range 62,790 km2 (range: 31,016–102,622 km2). The current area occupied by radio-collared females was 29,749 km2, while the area occupied in >140-year-old forest was 12,131 km2 (Wittmer 2004). • Mountain caribou distribution was considered to be severely fragmented, with projected future declines in local occupancy • The average time to quasi-extinction (< 1000 caribou in metapopulation) was 26 years, 84 years, and > 100 years for the pessimistic, most likely, and optimistic scenarios • These estimates may be conservative as a stage-structured PVA model for mountain caribou, based on evidence of inverse density dependence in female adult survival, suggested that all local populations were likely to become extinct over 100 years (Wittmer 2004). • Considered Endangered because the best estimate of the number of mature individuals was 1214 (IUCN endangered criteria: < 2500 mature individuals) • Enhancing caribou viability will require improving habitat suitability, managing access and human disturbance, and intensively managing the predator-prey system (MCTAC 2002).
Recovery planning • The best estimate of past population reduction was 19% in the last 30 years • The primary recovery goal for mountain caribou is to establish a viable metapopulation of 2500–3000 animals (MCTAC 2002). • Recovery actions must be undertaken to halt declines and facilitate positive population growth • A first step will be to ensure the maintenance of the larger populations within the core of their current range (i.e., Revelstoke, Wells Gray North, Wells Gray South, North Cariboo Mountains, and Hart Ranges) as well as connectivity between them • Socio-economic costs and benefits of recovering each local population, its viability in the long term, and its contribution towards long-term metapopulation persistence.
Populations in Canada • Intent/ capacity • All of Canada’s woodland caribou populations are considered endangered, threatened , or at risk. • Saving Canada’s woodland caribou from extinction, and in so doing, helping to ensure the long-term health of our boreal forest ecosystems • Legal protection of caribou habitat • Policies regarding resource development • Ecosystem conservation as an element of land use planning
USFWS contradictions • Sea lions and salmon • Spotted owls and logging industry • Selkirk caribou and industry _______________________________________ • 46 animals • 375,562 acres of undisturbed habitat • Confronted with inbreeding depression and fail to survive under same threats of predation and vehicle impacts as deer, elk and moose