Canada lynx

In 1998, the U.S. Fish and Wildlife Service proposed listing the Canada lynx, which ranges across the northern tier of states from Washington State to Maine, as an endangered species. To determine the number of lynx, the Rocky Mountain Research Station of the U.S. Department of Agriculture Forest Service developed a sampling kit to be used to collect lynx hairs at more than 10,000 scratching posts in a dozen states. 

Once returned to the Station, the hair was sent to the University of Montana, where a laboratory analyzed the DNA in the hair to identify the species. A positive control, a sample of Canada lynx hair, was run in each test to verify that the test could detect the species, and water was rim in each test as a negative control. At the completion of each test, the extracted DNA samples were frozen, and hair samples were stored to permit checking any specific sample if questions arose.6... 

In 1999 and again in 2000, seven officials of the U.S. Forest Service, the U.S. Fish and Wildlife Service, and the Washington Department of Fish and Wildlife sent Canada lynx hair samples to the laboratory with statements that the samples had been re-... 

R. Malfi, Canada Lynx Survey Unauthorized Hair Samples Submitted for Analysis (GAO-02-496T) (Washington, D.C. Government Accounting Office, March 6,2002). 

FIGURE 6.20.3 One-hundred-year record of population cycles of the snowshoe hare Lepus americanus) and the Canada lynx (Lynx canadensis), based on pelt records of the Hudson s Bay Company in Canada. Lack of anticipation in predator-prey systems lead to unstable population oscillations. (From Gotelli, N.J., A Primer of Ecology, Sinauer Associates, Sunderland, MA, 1998. With permission.)... 

Tyson, R., Haines, S., and Hodges, K.E. (2010) Modelling the Canada lynx and snowshoe hare population cyde the role of specialist predators. Theor. Ecol., 3, 97—111 (published online 21 August 2009). 

The Lotka model also has an ecological intepretation. In such a formulation A is an inexhaustible source of food for animals X which, in turn, constitute feed for animals Y. The death rate of predators Y, denoted as P, is proportional to their number whereas the death rate of animals X can be neglected, since a decrease in the abundance of population X occurs mainly as a result of predators eating them. We must also assume that the considered populations are isolated from other predators and other animals being a prey. A model system may consist of hares (X) and lynxes (Y). Abundant populations of these animals, living in the same area, occur for example in Canada. 

It is worth adding that in the studied populations of hares and lynxes, occurring in Canada, oscillations in their abundance have been actually observed. 

Fig. 15.11. (a) Time series of lynx numbers in six different regions in Canada (after (2))... 

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