Atlas der Säugetiere Nordrhein-Westfalens

Kanadischer Biber

3 entries

North American beaver

Rote Liste NRW: nb nicht bewertet

  entry

Castor canadensis

Originally distributed exclusively in the Nearctic, the Canadian Beaver (Castor canadensis), very much resembles its European cousin exteriorly as well as in its behaviour, although they have been separated from each other for millions of years, and they cannot be crossed due to different sets of chromosomes [karyotypes]. Due to intentional introductions, today there are large and expansive occurrences in South America and in Finland and north-western Russia.
Since the 1990s a population was established around the Eifel Zoo in Pronsfeld (Township Bitburg-Prüm, Rhineland-Palatinate), which is growing and spread to Luxemburg and Belgium. Because the Canadian Beaver is considered an invasive species with a strong potential to spread, which can displace the European Beaver (for example in Finland), there is an attempt in the region to exterminate the Canadian Beaver, wherein the different countries use different approaches. On 3 April 2009, the Canadian Beavers in the Eifel Zoo were replaced by European Beavers (Castor fiber).
In January 2011, the first Canadian Beavers appeared in the extreme SW of NRW (Euskirchen County) in the area of Marmagen (MTB 5505/1), which was unequivocally documented by genetic studies. Tracks and clues showed that the beavers lived there for at least a year. The attempt to capture the animals failed. However, the population disappeared by itself (as of Nov. 2014).
In autumn of 2013, a second, genetically unequivocal population was discovered near Blankenheim-Wald (MTB 5505/4). Within a few days a Canadian Beaver was captured here, which was than referred to an animal care facility in Bavaria. Since then there were no more indications of Canadian Beavers in NRW. Because the measures in Rhineland-Palatinate (capture, sterilization and release) do not yield the desired success — repeatedly in 2013/2014 three-year old Canadian Beavers were captured in Luxembourg on the border to Rhineland-Palatinate — advances into NRW have to be expected at any time.

Author

Lutz Dalbeck

Citation

Dalbeck L (2024): Kanadischer_Biber (Castor_canadensis).In: AG Säugetierkunde NRW — Online-Atlas of the mammals of North Rhine-Westphalia. Downloaded from saeugeratlas-nrw.lwl.org on 2024/12/21