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WSU/Pend Oreille Extension introduced the Sense of Place series in 1999, with a focus on local landscape and natural history of Pend Oreille County, Washington. A partnership with the Kalispel Tribe of Indians Natural Resources Department has allowed us to expand this program through EPA funding to include more classes, a newsletter and this website.

Ghosts of the Selkirks

by Jon Almack, Senior Wildlife Research Biologist, Mountain Caribou Investigations, Washington Department of Fish and Wildlife

Mountain caribou… they are often called Ghosts of the Selkirks. Perhaps the name refers to how their chocolate brown to dark gray coat blends in so well with the high elevation forests they roam. Or perhaps the name stems from the fact that mountain caribou are the most endangered large mammal in the lower 48 states. These unique woodland caribou (Rangifer tarandus caribou, mountain ecotype) have been federally listed as an Endangered Species since 1984. Since then, a team of federal, state, and provincial agencies, has been working to recover our mountain caribou population in northern Idaho, northeastern Washington, and southern British Columbia (BC). The agencies involved include the US Fish and Wildlife Service (USFWS), US Forest Service (USFS), Washington Department of Fish and Wildlife (WDFW), Idaho Department of Fish and Game (IDFG), and British Columbia Ministry of Land, Water and Air Protection.

One method for preventing short-term extinction of a population is to transplant wild animals into the local herd. Guided by the Selkirk Mountains Woodland Caribou Recovery Plan, IDFG transplanted three groups of 20 caribou each into the Selkirks in 1987, 1988, and 1990. Following the same plan, WDFW also transplanted three groups into the Selkirks: 19 in 1996, 13 in 1997, and 11 in 1998. These 43 caribou were captured from source populations in central BC. We also captured nine resident animals as a control group. Each caribou was fitted with a radio collar that allowed us to monitor locations of animals by aircraft and determine the fate of each animal from April 1996 through the end of our field project in July 2004. Our major objectives were to augment the resident population of approximately 30 caribou to stave off extinction, to calculate annual survival rates for the caribou population, to determine causes of caribou mortality, and to make recommendations for future mountain caribou recovery efforts in the Selkirks. We also conducted a four-year cougar investigation to determine the level of cougar predation on caribou and to identify local cougar population parameters and habitat requirements.

We investigated each caribou mortality to determine cause of death and to calculate annual survival rates for all radio-collared caribou. We compared the results by transplant or resident status, by transplant group, by sex, and by season of the year. Since caribou are a natural prey species and it seems that just about every other critter out there feeds on caribou carcasses, we recorded a large number of caribou mortalities (24) where we could not determine the cause of death… there just was not enough of the carcass remaining to allow for a complete forensic examination. We found that seven caribou were killed by cougars, most of these caribou were likely killed by one male cougar in BC. When this cougar was killed legally by a hunter in BC, the caribou deaths virtually stopped. We documented two caribou killed by grizzly bears, one died in an accidental fall down a steep slope, and two were poached (one near Northport, Washington, and one near Salmo, BC). We had only partial data from four caribou; three of these animals emigrated to the Nakusp herd in BC (about 100 miles north of our population) and one caribou dropped its radio collar.

We calculated an overall caribou survival rate of 76% and found that it was about the same for transplant and resident caribou and for both males and females. Survival differed slightly, depending on which year the animal was transplanted. There was a distinct difference in the season of mortalities, with most caribou deaths occurring from July through September and no mortalities recorded in winter. Both transplant and resident caribou died at a higher rate during the three capture years. However, all transplant and resident animals showed significantly higher survival rates (up to 76%), once the animals made it through the year they were captured. This is important to note, because a survival rate above 75% is generally needed to have an increasing population. With our current population estimate of about 40 caribou, assuming things stay pretty much the same for a few years, we could see a gradual increase in the Selkirks caribou population.

Besides the simple arithmetic need of having enough caribou to prevent extinction and to support an increasing population, having quality habitat is most important for mountain caribou survival. On the USA side of the border, federal requirements for protecting and improving caribou habitat have been in place for years and are reinforced by USFWS and USFS regulations and policies. However, on the BC side of the border, habitat protection and improvement has decreased over the past eight years, due to changes in provincial forest management policies. The current BC administration has severely reduced the size of the Caribou Recovery Zone in Canada. The BC government also allows logging in important high-elevation caribou habitats and does not manage winter recreation. Left unchecked, these management concerns could lead to an overall decrease in habitat quality and availability for this caribou herd. Therefore, the survival of the Selkirk caribou is still questionable.

Persistence of the endangered Selkirk Mountains woodland caribou population will likely depend on several key steps: continued transplants (whether from wild populations or from a captive herd), supportive major changes in forest management strategies for caribou habitat in British Columbia, adequate recovery funding in the USA, and, most of all... public support.

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