Atlas der Säugetiere Nordrhein-Westfalens

Bisamratte

847 entries

Muskrat

Rote Liste NRW: u Ungefährdet

  entry

Ondatra zibethicus

This large rodent belongs to the voles and has a head-and body length of 250 - 350mm (for comparison: Field Mouse HB Length 93 - 120mm) and a weight of over 1 kg. It carries a scaled, laterally flattened tail, which can be 200 - 250mm long. By its short, blunt head and invisible throat, the animals appear stout and compact. The ears barely emerge from the fur. The coloration is dark-brown to chestnut-brown, on the sides lighter and underneath grey-white, slightly brownish.
The species is optimally adapted to a life in and on the water and colonises flowing and standing water bodies. The food consists mainly of plants, for example, cattails, iris and reeds. Aside from vegetarian food, mussels are also eaten. Their feeding activity can create changes in their habitat. Thus, in the NSG [nature protection area] Heiliges Meer, the reed zone was greatly decimated in parts.
Muskrats can cause damage to water bodies and dams by digging their burrows into riparian slopes and thereby excavate the banks, which can then collapse. This is also the reason an area-wide net of official muskrat catchers was established with the advance of the muskrat. Since 1 January 2000, this is no longer a state responsibility and the fight has been left to the water and soil management authorities who potentially pay a premium per killed animal (in 2014 in Steinfurth County: 9 Euro).
The muskrat is a new resident from North America, which was kept in fur farms. In Prague, a few animals were released and in the following decades, animals escaped repeatedly from farms in Poland as well as in France. The large rodent spread quite quickly following bodies of water and its advance is well documented. For example, in the Westphalian part of the state the first animals appeared in 1960, and ten years later, the muskrat had already occupied the whole of NRW.

Author

Manfred Lindenschmidt

Citation

Lindenschmidt M (2023): Bisamratte (Ondatra zibethicus).In: AG Säugetierkunde NRW — Online-Atlas of the mammals of North Rhine-Westphalia. Downloaded from saeugeratlas-nrw.lwl.org on 2023/03/26