PredatorsBecause beavers spend most of their lives either in the water or in a lodge protected by water, they have very few natural predators (Rosell and Czech, 2000). Of the successful predators that they do have, however, wolves and humans are the major two. Other predators include bears, lynxes, wolverines, red foxes, and dogs. In North America coyotes and possibly river otters also prey on beavers. There is question of whether river otters eat found carcasses of beavers or if they actually hunt and kill them; regardless, the beaver is rarely found to be part of river otters' diet. (Rosell and Czech, 2000) Like most other mammals the young of beavers are more likely to fall victim to predators than adults (Wheatley, II. Sex, Age, and Family Status, 1997). Beavers rely on their heightened sense of hearing to detect and evade predators. Sun and Mueller-Schwarze recorded that tail slapping was the most frequently observed alarm call in their 2003 publication. Tail slapping is simply when a beaver slaps its tail on the surface of the water, making a noise that can be heard by humans 100 meters away. Other beavers recognize tail slapping as an alarm call and respond by diving into the water. Beavers tail slap at the approach of humans, at the presence of unfamiliar noises, and at the presence of unfamiliar odors. Some times a beaver will slap the water with its tail in response to another beaver's slap before diving. Beavers will be more likely to respond to tail slaps produced by older beavers than younger ones. The tail slap of a younger beaver sounds different because of their smaller tails. This lack of response is most likely because younger beavers are still learning when to tail slap and when to not. There are probably more tail slaps produced by young beavers that are not in response to a predator or threat, so others do not take their slaps as seriously. Humans have become a major threat to beavers, because of destruction of habitat caused by water pollution, silting of streams, and deforestation ("Beaver: Canadian Domain," 2004). Many people do not sympathize with efforts to save dwindling beaver populations, especially in Europe, because there is a stigma against them. Some believe that beavers themselves are destructors of habitats, because they cut down trees and dam up streams (Deufel and Kattner, 2004).
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