Voyageurs National Park may owe its very existence to a furry, flat-tailed rodent. The 218,000-acre park, 40% of which is covered by water, is the perfect habitat for one very unique mammal… the American beaver. Beavers have historically played a pivotal role there, since the titular French-Canadian “voyageurs” first came to the area to trade with the Ojibwe tribe for beaver furs. While trapping is no longer allowed in what is now the national park, beavers continue to make an impact on the ecosystem.
Beavers are the largest rodents in the United States and are one of the only animals (outside of humans) who actively alter their habitat to suit their needs. The animals mate for life, and beaver parents raise their young in structures they build called “lodges.” These lodges are constructed on the edges of ponds and lakes and are made of mud and sticks chewed by the beavers. By locating the single lodge entrance underwater, the parents are better able to protect their babies (called “kits”) from predators. Beavers’ construction talents can alter entire ecosystems. If there is not an existing body of water large enough on which to build their lodge, they will dam up a river or stream to create a suitable habitat for their homes. This activity will flood the surrounding area, killing trees and undergrowth. The resulting wetland will then attract insects, fish and other wildlife, greatly increasing the area’s biodiversity.
Not only are beavers great architects, but they also have some other truly unique characteristics. Beavers have two large incisors which grow continuously throughout their life. They use these teeth to cut down trees and branches. Beavers are also known for their distinctive large flat tail. Most people would correctly assume that they use it to help with swimming, but did you know that they also use it to help balance while standing up to chew branches? They will also slap it on the surface of the water (making an incredibly loud noise!) in order to scare away any intruders.
As one of the many beloved animals that call Voyageurs home, beavers have been studied extensively by park staff. During a research project from 2006-2009, biologists tagged nearly 500 beavers. By tracking the tagged beavers over the next few years, they were able to determine that young beavers can travel up to 30-50 miles from where they were born! This mobility may be due to the interconnected lake system in Voyageurs, which allows young beavers to travel long distances without ever leaving the water (and thus avoiding predators). Beavers are adapted quite well to water. They can hold their breath for up to 15 minutes and have see-through eyelids which they use as goggles!
Today the highest recorded density of beavers in the U.S. can be found in the protected waters of Voyageurs: between 3,800 to 4,750 animals, based on 948 active beaver lodges found in a recent park study. If you visit Voyageurs National Park, you may be lucky enough to see a lodge or even catch a glimpse of a beaver, and there are things you can do to help protect these wonderful animals. Make sure to always keep your distance from any wildlife you encounter, both for their safety and yours. Also, do not approach, touch, or walk on a beaver lodge. This could damage the structure and disrupt or even injure the animals inside. You can learn more about the beavers and other wildlife that call Voyageurs home by clicking here.
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