The official headcount will not be available until the end of the month, but a good look into the trees along the Mississippi River shoreline gives the distinct impression bald eagles are plentiful this year in the Quad-Cities.
The annual two-week national Midwinter Eagle Survey, which Iowa has taken part in since 1991, reveals dramatic ups-and-downs in bald eagle populations. For instance, between Clinton and Muscatine, the eagle tally in January 1993 was only 24. In 2004, however, the population spiked to 1,352.
Some mass eagle sightings in the Quad-Cities suggest 2014 will produce high numbers. In one collection of trees near the Rock Island Arsenal and Lock & Dam 15 Saturday, eagle watchers were counting as many as 50 of the birds of prey.
Stephanie Shepherd, a wildlife diversity biologist for the Iowa Department of Natural Resources, said the area's cold, early winter probably drew the eagles to the Quad-Cities and other riverfronts.
"The Mississippi traditionally is a popular wintering area, and about 50 percent of the count (in the surveys) come from there," she said Thursday. "They respond to the weather, looking for open water. If there's a shortage of open water, they're more concentrated."
The seemingly high number of eagles is cause for celebration for Joe Taylor, the executive director of the Quad-Cities Convention & Visitors Bureau.
"The super cold temperatures will make for great eagle watching the next several days," he wrote in a news release Saturday. "Just as these are the coldest temperatures in 20 years, we will likely have the greatest number of eagles congregating in the Quad-Cities in 20 years.
"The eagles will be more concentrated around the small patches of open areas on the river. I saw more than 50 eagles from East Moline to Port Byron."
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A group of 10 people, taking part in a Saturday morning eagle watching tour on the Arsenal, got what they came for.
"We easily counted probably 20 to 25 eagles this morning," Park Ranger Mike McKean said, adding another 20-plus people were signed up for an afternoon tour. "The eagles were pretty active, flying and fishing."
The U.S. Army Corps of Engineers also conducts an annual eagle count, which runs from Dec. 5 to Feb. 26, McKean said. The districtwide survey counts eagles from Lock & Dam 11 to 22, he said.
Although there is speculation that eagles arrived earlier this year because of early snow cover, making it difficult to hunt rabbits and rodents, Shepherd said the food-motivation speculation is innacurate.
"It's not that they won't take rabbits or mice, but they prefer fish and are scavengers," she said. "They'll take road kill, for sure. When the open water gets limited, though, you'll see they really are after fish."