Muskrat, Ondatra zibethicus

Stevens, R.T., T.L. Ashwood, and J.M. Sleeman. 1997. Mercury in hair of muskrats (Ondatra zibethicus) and mink (Mustela vison) from the U.S. Department of Energy Oak Ridge Reservation. Bull. Environ. Contam. Toxicol. 58 720-725. 

Muskrat, Ondatra zibethicus August 1960, Oak Ridge, Tennessee, from settling basin for radioactive wastes, single most radioactive animal Brain vs. eyes ... 

In most countries in the Northern hemisphere the muskrat, Ondatra zibethicus, is mainly appreciated for its beautiful muskrat or "bisam" fur. It was for this reason that it was introduced from America into Czechoslovakia and other European countries early in the 20th century. In the Netherlands, however, it is now a major pest, damaging the banks of the many canals and dikes, so vital for a country lying largely below sea level. This threat is evident from the schematic drawing of Figure 1. 

The muskrat (Ondatra zibethicus) is a rodent, around 30 cm long, belonging to the family of voles it is valued especially for its fur (Fig. 3.40). Originally native to North America, the muskrat is also found nowadays in central Europe. The muskrat has pockets near its sexual organs, which produce a musk-like scent. A chemical process of extracting it was developed in the 1940s, but it did not prove commercially worthwhile. [158]... 

Since the 17th century it has been known that muskrats (Ondatra zibethicus) secrete a glandular substance with a musky odour in order to mark their territories. 

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