Frogs, toads, and beavers prove to be a beautiful relationship
When one visits Glacier National Park, the first thing that comes to mind for most visitors isn’t the frogs and the toads that live there. The mountainous terrain and the streams that flow from it, however, are good frog and toad habitat, however, and unlike many places in the world, Glacier’s amphibians are doing pretty well, biologist Leah Joyce of the University of Montana said in a recent talk.
Joyce has been studying the Park’s amphibian population with support from the Jerry ONeil Fellowship funded by the Glacier National Park Conservancy, as well as other sources.
The chytrid fungus has decimated amphibian populations worldwide. It infects the skin of creatures like toads and frogs and inhibits the animals’ ability to regulate nutrients in their body. It can’t be seen with the naked eye, but many frogs and toads that are infected die from it.
Its origins come from the Korean Peninsula, Joyce notes, and it was spread with the worldwide pet amphibian trade. There are about 7,400 species of amphibians worldwide and at least one-third of them are threatened with extinction.
Glacier only has six amphibian species — The Columbia spotted frog, the Pacific tree frog, the boreal chorus frog, the tailed frog, the boreal toad and the long-toed salamander.
The most common are the boreal toad and the Columbia spotted frog.
Joyce’s research to date has found that the chytrid fungus does exist in the Park, but it hasn’t decimated the populations like it has in other parts of the West.
Why?
Joyce’s research suggests that beavers are playing a role in the success of the park’s frogs and toads. Beavers are common in Glacier’s streams and they live up to their busy reputation, building dams, cutting down trees and creating ponds. Those ponds often have floating vegetation and pools of stagnant water.
In the summer months, when the chytrid fungus is infecting the frogs and toads, those pools, warmed by sun, get hot, too.
Chytrid fungus dies at about 30 degrees Celsius, or 86 degrees Fahrenheit. The frogs and toads love this warm water. Not only is it good habitat, full of insects and bugs to eat, it also kills the chytrid fungus infecting their skin, Joyce surmised.
“It’s been hard to find frogs and toads (in Glacier) that haven’t been in beaver ponds,” she noted.
Toads are a terrestrial creature, but they breed in the ponds and live around them.
Other regions of the West don’t have the beaver populations that Glacier does. Many populations were trapped out in the early 1900s and haven’t recovered. In some areas, efforts are underway to restore beaver populations, while some have already been restored.
In the Custer-Gallatin National Forest north of Yellowstone National Park, 129 beavers were released into drainages north of the park from 1986 to 1999.
Yellowstone aerial surveys began in 1996 with a count of 49 colonies and increased to 127 by 2007; dropping to 118 in 2009 and 112 in by 2011, according to the most recent data, and has probably continued to grow in the past 15 years.
In states like Wyoming, Nevada, and Washington, efforts to restore beaver populations on public lands are underway.
That could be good news for the West’s frogs and toads.
Meanwhile, Joyce is continuing her research in Glacier. She notes that amphibians are a measure of ecosystem health. When they’re present, it means the food chain is working properly. Like many creatures, they require clean, unpolluted water to survive.
And that’s something to croak about.