February 14, 2013
Beaver Activity Gives Canada Geese Earlier Access To Thawing Ponds
April Flowers for redOrbit.com - Your Universe Online
A new study from the University of Alberta, published in a recent issue of Mammalian Biology, reveals that busy beavers help Canada geese get an earlier start when the birds fly home and begin nesting in the spring.
The researchers found that in ponds in Alberta where beavers were active, an earlier thaw of winter snowpack resulted, giving Canada geese a better chance at reproductive success. This study is the first to link early season nesting habits of Branta canadensis in a Northern climate to beaver activity.
Glynnis Hood, an associate professor in the Department of Science at the UofA's Augustana Campus, led a team of researchers who surveyed 32 active and 39 inactive beaver ponds at Miquelon Lake Provincial Park in east-central Alberta.
They found that in active beaver ponds, open water occurred 10.7 days earlier, especially in water that was next to main beaver lodge entrances and food caches. Snowpack tended to be, on average, 2.4 inches shallower on active ponds as well.
Hood said that the beaver activity warmed and thawed the water, making it a more welcoming habitat for the geese to nest. Active ponds housing island lodges, and open water, provide food resources and safer nesting opportunities away from land predators for the geese.
"Having access to safe nesting grounds and ample food is necessary for Canada geese to raise at least one set of offspring before fall migration," Hood noted.
Hood noted that the open water was used by several other animals as well, including coyotes, foxes, weasels, moose, deer, ravens and other birds. This reinforces earlier findings which indicated that beavers are a vital keystone species, contributing to the success of other wildlife and protecting boreal wetlands against drought.