Riparian Zones and a Critter Quiz

Hello, this is Jim Goodwin.

In a minute I’ve got a critter quiz for you, but first, a word about the huge importance of riparian areas in semi-arid Utah, the second driest state in the union. Utah State’s Extension Service calls riparian zones the green ribbon of life alongside a stream. They are shadier, cooler and moister than adjacent environments.

And with a diverse mix of plants and animals, our few riparian corridors are heavily used by wildlife for food, rest and shelter.

Ok, now for our critter quiz.

What is the largest rodent in North America? Here’s a hint: they can be up to four feet long and weigh 40 to 60 pounds.

Did that do it? No? Alright, this clue will: They spend much of their life in water. They have a beautiful brown coat, a broad flat hairless tail and big orange buck teeth that continually grow, which is why they chew and chew and chew.

Click for larger picture, Beaver with branch in water, Courtesy US FWS, Steve Hillebrand, Photographer
Beaver with branch in water
Courtesy US FWS,
Steve Hillebrand, Photographer
Good, you got it . . . it’s the North American beaver. Or as Utah environmental author Chip Ward calls them: the Flat Tail Climate Hero for the restoration of damaged watersheds. Beaver are amazing aquatic engineers, second only to humans in their ability to manipulate their environment.

In our nation’s history, they’ve played a big role in literarily shaping our western landscape.
Joe Wheaton, Utah State wildlife and a beaver expert, rightly calls the work of the beaver “cheap and cheerful restoration” of our heat stressed watersheds.

In the wild, these mostly nocturnal animals, normally live five to ten years.
Fortunately, they are rarely killed for their pelts these days. Beaver are usually monogamous. They will produce up to 10 babies. The young kits will stay home until they are two or so, before they will take off on their own.

Beaver are master aquatic builders. the original geo-engineers. They build dams to flood areas for protection from predators, for access to their food supply, and to provide safe underwater entrances to their dens. Their dams create beautiful riparian habitat for many other animals, birds, fish amphibians, insects and plants. The flooded areas slow the flow of water and sediment downstream and raise the area water table.

Aspen, cottonwood, willow and dogwood are their preferred tree. Those trees regenerate quickly after beaver topple them. When their ponds freeze over, beaver jam smaller branches into the mud at the bottom of their pond for food storage.

Beaver dams can be 5 to 10 feet high and 150 feet across. They are constructed with branches, stones, and plants and plastered together with mud. Over 1200 beaver dams have been counted in northern Utah’s Bear River mountains alone. The World’s largest beaver dam in Canada is 2,789 feet in length. That’s more than 9 football fields.

Yes, sometimes beaver can be a nuisance to human property and activities. Often, learning to live with beaver and the many benefits they can bring, can be a solution. There are simple time-tested ways to prevent flooding. But if nothing works, they can be live trapped and moved to another area. There’s no need to shoot them.

Be a “beaver believer.” Here are some organizations you can check with to learn more:
Utah State wildlife researchers Wally McFarland and Joe Wheaton have created something called the Beaver Restoration Assessment Tool to track beaver dam building activities and their effects throughout the state.
The Bear River Watershed Council in Cache Valley and Mary O’Brien with the Grand Canyon Trust in southern Utah are excellent organizations to contact.

I’m Jim Goodwin for Wild About Utah.

Credits:
Image: Courtesy US FWS, Steve Hillebrand, Photographer
Text:     Jim Goodwin

Additional Reading:

Beaver Restoration Assessment Tool, http://brat.joewheaton.org/

Bear River Watershed Council, http://www.brwcouncil.org/

Grand Canyon Trust, http://www.grandcanyontrust.org/

Beaver Castor canadensis, National Geographic, http://animals.nationalgeographic.com/animals/mammals/beaver/

Big Bend Habitat Restoration Project: A Natural Work of Heart, Open Spaces-A Talk on the Wild Side, US FWS, http://www.fws.gov/news/blog/index.cfm/2016/3/25/Big-Bend-Habitat-Restoration-Project-A-Natural-Work-of-Heart [Accessed March 31, 2016]

Beaver Dams Strengthened by Humans Help Fish Rebound
60-Second Science – July 25, 2016 – By Jason G. Goldman02:29 http://www.scientificamerican.com/podcast/episode/beaver-dams-strengthened-by-humans-help-fish-rebound/ Also available through the podcast https://itunes.apple.com/us/podcast/60-second-science/id189330872?mt=2