SALT LAKE CITY — Every winter, flocks of bald eagles gather along the Great Salt Lake, where there's plenty of carp to eat in freshwater bays.
Saturday was Bald Eagle Day at traditional viewing spots across Utah. The birds of prey tend to concentrate at Farmington Bay, about 15 miles north of Salt Lake City, where eagles look for patches of open water to pluck out carp with their sharp talons.
"People don't realize the eagle concentration is associated with the huge carp population out there," said Phil Douglass, an outreach manager for the Utah Division of Wildlife Resources. "It's a perpetual thing. There's always lots of carp."
Farmington Bay has miles of dikes and levees that keep water levels at about 18 inches deep, ideal for waterfowl and eagles.
About 50 bald eagles are marking time at Farmington Bay this winter. Other seasons have seen as many as 458 eagles, Douglass said. Nobody knows why the numbers of wintering eagles from Canada, Alaska and northern states fluctuate at Farmington Bay from winter to winter.
"I recall years when we were lucky to get one bird. It's like inviting people to a party and forgetting to provide food and beverage," said Bob Walters, coordinator of DWR's watchable-wildfire program, who started Utah's Bald Eagle Day 24 years ago. "And yes, I've been at every one. We don't control the weather."
Walters said that one bare tree along a Farmington Bay dike is famous for holding 25 or more eagles at a time, when the birds aren't soaring or hunting.
"They're scavenging almost anything, domestic animals included," Walters said. "They take advantage of kills by golden eagles, or gang up on jack rabbits or deer. They also hunt waterfowl. "
The Great Salt Lake Nature Center at Farmington Bay was sponsoring a photography workshop Saturday courtesy of $250,000 worth of equipment on loan from Canon USA Inc.
Officials marked the occasion by renaming the building after Robert M. Hasenyager, a retired DWR employee who was the driving force behind the nature center.
It's a fitting tribute for Hasenyager, colleagues say.
He was so enthusiastic," said Douglass. "He had the building designed by students for students. That's the principal use for this nature center, for Davis County children."
Eagles shrug off the bitter wind and cold of Farmington Bay in winter. They puff out their feathers to keep warm while perching.