Clethrionomys rufocanus

Only a small portion (0.037%) of copper mining wastes discharged into riparian wetlands is bioavailable to resident rodents, as judged by measurements of copper in carcasses of mice and voles. Populations of brown-backed voles Clethrionomys rufocanus) and other microtine rodents (Microtus spp.. Lemmas) are low or absent in the vicinity of Russian copper-nickel smelters. The reasons for this decline are unknown but may be due to a decrease in the abundance of important food plants (lichens, mosses, seed plants), and - as shown in preference studies - to an avoidance of plants from the contaminated area. Bank voles (Clethrionomys glareolus) from areas of Poland subjected to various degrees of industrial contamination have copper concentrations in tissues comparable to those in animals from polluted sites in North America and the United Kingdom... 

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