June microburt topples Lake Granby osprey nests
July 20, 2011
The storm that wreaked havoc on roofs, trees and outdoor furniture in the Granby area on June 30 was also a threat to young osprey.
The U.S. Forest Service Sulphur Ranger District, which keeps close tabs on osprey nesting in the area, has reported that at least four osprey nests were lost in the storm on the eastern shore of Lake Granby.
All the nests were active with eggs and chicks, said U.S. Forest Service Wildlife Biologist Brock McCormick. On Shadow Mountain Reservoir, no known nests were destroyed.
Nests along Granby could have been destroyed from entire trees falling.
“We’ll just have to hope they (the osprey) rebuild a nest in a more sturdy tree,” McCormick said.
Grand County accounts for the highest elevation of breeding ospreys and the largest population of the species in the state of Colorado.
There are about 50 osprey nests, mostly located around Lake Granby, Shadow Mountain and Grand Lake.
The highest density, he said, are on the Shadow Mountain Reservoir islands that are closed during certain times of year to allow the birds space for nesting.
Even with the tornado-like storm just before the Fourth of July weekend, chick counts appeared to be average in spite of this spring’s late snowstorms. This is surprising since an osprey already sitting on eggs does not have the option of seeking shelter during a storm without losing her clutch of eggs, McCormick said.
“We’ve got some pretty tough osprey,” he said. Osprey winter in Texas and the Gulf of Mexico.
Osprey, or “fish hawks,” feed exclusively on live fish. As a bird of prey, such raptors are at the top of the food chain.
“A good osprey population is a good sign for the health of the rest of the ecosystem,” McCormick said.
Since their nests are noticeable at the tops of trees, “people like seeing them,” he said. “They are a good opportunity for the public to see wildlife.”
But dead and dying trees in the area leave fewer options for nesting, especially when remaining healthy trees exposed to high winds can topple too. During osprey population crashes in the 1980s, the U.S. Forest Service tried to encourage nesting by building tall wooden platforms.
Now that populations have returned, new platforms are only sometimes built – with the help of Mountain Parks Electric – for those six to eight osprey a year determined to build nests on power lines, McCormick said.
– Tonya Bina can be reached at 970-887-3334 ext. 19603.