By Angela Vander Eyken
Beavers are easily one of the most fascinating and unique creatures in our landscape: they have impressive paddle-like tails, lush shiny fur, self-sharpening teeth, and even ear and nose valves that close when diving! With that said, it may seem quite surprising that they share many similar traits to human beings. For one, they too live in family units and typically choose one spouse or mate for a lifetime. They also groom themselves (and each other) with their specialized “claw combs” located on their hind feet, and they even they have two separate chambers in their homes for eating and sleeping. But perhaps the biggest similarity is that both beavers and humans are considered the largest influencers of a landscape. In fact, beavers are second only to us in their ability to alter a landscape – albeit in a very different way. While humans are typically known for tearing down forests, filling in wetlands, and realigning water courses, beavers are hard at work doing the exact opposite – creating ecosystems. It is no wonder that they have been fittingly referred to as “ecosystem engineers” by scientists for decades, as well as “sacred centers of the land” by Indigenous peoples for centuries!
One of the main reasons why they have been so admired and respected throughout history is because they are such hard workers - hence the term “busy beaver”. When a beaver moves into a landscape, it eagerly gets to work building a dam to create the optimal habitat for itself. In fact, beavers innately hate running water so much that even just the sound of rushing water playing from a speaker is enough to cause them to build a dam! As a result, over 84% of the water in The Land Between bioregion exists because of the mighty beaver.
But beavers are not the only ones who benefit from shaping the landscape – their hard work is most often enjoyed by a multitude of other species. When a beaver builds a dam, it converts a fast-flowing creek or river system into a slow-flowing pond or wetland with new water chemistry and vegetation types. The resulting beaver pond (or “impoundment”) becomes suitable for a whole new suite of species once the vegetation has had time to transition to more water-loving species. More importantly, it serves as a crucial nursery ground for early stages of life, including fish, frogs, salamanders, turtles and even birds. This highly complex and diverse habitat supports the growth and development of young animals by offering excellent sources of shelter and food. For example, beaver chews and their food stashes provide great hiding spots for fish and turtles, whereas newly established duckweeds, pondweeds, crustaceans, and mollusks provide food for numerous waterfowl. It is for this reason that beavers are often credited with the ability to create highly biodiverse habitats.
Even birds such as the Pileated Woodpecker, Belted Kingfisher, Sharp-shinned Hawk, Osprey Eagle, and various Swallows and Nuthatches that you see and hear in a nearby forest are likely the result of a myriad of habitat structures and food sources offered by a nearby beaver pond. In fact, beavers are known as a “keystone species” because without them our meadows and wetlands would disappear, the rate of erosion would increase, and we would lose water-loving species of fish, turtles, birds, and amphibians, not to mention all of the other species that rely on these animals as well! A great example is the threatened Eastern (Algonquin) Wolf who would have much less food supply in the summer if it weren’t for the easily-preyed-upon beaver venturing out of its home to feast on a nearby stand of trees. Another example is the Moose who would have no Aspen, Willow, or Cottonwood to forage on if it weren’t for the beaver’s pruning which encourages early successional tree growth, or their ability to flood creeks which supplies water to tree roots along the shore.
Even the seemingly nuisance behaviours and habits of the beaver have their purpose. Their typical activities - such as digging burrows and canals to reach other feeding areas, creating food caches to supply winter food, and constructing dams to raise water levels - all affect the hydrology, and in turn, the sedimentation processes and water chemistry of a watershed. In fact, beavers and their ponds can counteract pollution by filtering water, storing carbon and ridding of phosphorous, nitrogen and other pollutants from agricultural practices and fossil fuels. For example, some beaver ponds have been shown to store up to 1,000 times more nitrogen compared to a regular stream, mainly due to the buildup of sediment and microbes which are capable of fixing nitrogen into a more usable and environmentally-friendly form. In this fashion, beaver dams can filter through toxins, such as pesticides, to provide cleaner water for human use further downstream. They also contribute to adding organic matter to the water from adjacent terrestrial areas by felling trees and stashing them in their aquatic habitats. Since the entire tree is never fully eaten by the beaver, the rest decays to feed organisms at the bottom of the food chain. Talk about recycling!
Perhaps the biggest favour that beavers do for us is preventing flooding and drought, both of which are being exacerbated by climate change. Drought can wreak havoc on crops, reduce water supply for livestock, and limit drinking water sources for humans. Flooding also causes severe property damage and poses a risk to human safety. Since beaver ponds store more water than creeks or rivers, they provide a continuous source of flow throughout even the driest summers. They also recharge groundwater sources by elevating the water table, and they help mitigate flooding by collecting and pooling stormwater runoff and sediment. One study estimated that a local economy could save millions of dollars by reintroducing beavers into a watershed and allowing them to construct dams which would store water for irrigation, filter sediment from drinking water, and improve hunting and fishing opportunities.
So why are humans still trying to control beaver populations despite the benefits that they provide? Unfortunately, many people see beavers as tyrannical, unpredictable, and destructive, particularly in areas where human attempts to alter the landscape conflict with beavers’ attempts to do the opposite. As a result, they are often killed or trapped and relocated to different areas for fear that they will cause property damage from felling trees, removing vegetation, and creating floods from failed dams. While this may be true in some cases, most of these conflicts occur where humans have significantly infringed upon beaver habitat. Fortunately, there are many things we can do to ensure that we live in healthy harmony with these admirable creatures.
For one, we should avoid killing or removing beavers since new ones will often return to the same suitable habitat in place of the missing beaver(s) anyway. In addition, removing a beaver from its home can result in flooding since there will be no beaver to maintain the dam and prevent it from breaking. Both of these options have proven to be inefficient and costly in past efforts. Indeed, the best solution is to learn how to understand and coexist with beavers in a peaceful, respectful way. For more information on how you can protect your vegetation from beavers or about different water level control devices that can be used to mitigate flooding (not on municipal property) check out the Beaver Manual produced by the Animal Alliance of Canada: https://www.animalalliance.ca/wp-content/uploads/2018/04/Beaver-Manual_May-2016.pdf. It is important to remember that helping to save beavers and coexisting with them in a synergistic way not only helps keep their populations healthy, but also all of the other animals who call The Land Between home - including us!
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