‘Tis the season to see golden eagles, population seems to be growing each year – Hudson Star Observer

When Ryan Brady initiated a spring raptor count at the Northern Great Lakes Visitor Center while a student at Northland College in 1999, his ornithology professor, Dick Verch, had never documented a golden eagle near Ashland, Wisconsin.

The first bird Ryan spotted, on the very first day, showed the slightly V-shaped silhouette, small dark head, and dark tail of a migrating golden eagle. Both birders were thrilled.

In the second year of the project, Ryan counted almost 50 golden eagles during the spring migration season. In Duluth, the West Skyline Hawk Count spotted 41 GOEA in a single day on March 17.

Golden eagles are very similar in size to bald eagles, and can be confused with immature bald eagles who lack a white head and tail.

GOEA is the alpha code for golden eagles. Alpha codes are abbreviations of bird names that are employed by ornithologists as shorthand. These codes are established by The Institute for Bird Populations.

Now a conservation biologist in the Bureau of Natural Heritage Conservation, at the Wisconsin Department of Natural Resources, Ryan Brady is still counting and researching birds in northern Wisconsin. Ryan told me recently that part of the uptick in golden eagle sightings is due to an increasing population. Biologists arent completely sure whats behind the increase.

Golden eagles were not quite as impacted by DDT as other raptors, because they prey mostly on mid-sized mammals like rabbits and squirrels, which dont accumulate DDT to the same degree that insects, small birds and fish do. So the banning of DDT alone cant explain their comeback.

Maybe wildlife protection laws simply mean fewer of them are getting shot? Maybe they are adapting to wintering in our human-dominated landscapes by eating our abundance of turkeys and roadkill deer? Still, humans (collisions with cars and structures and ingesting lead shot) are their largest source of mortality.

A portion of the increase in sightings may just be a result of looking more. With the proliferation of raptor counts like the one Ryan started, as well as trail cameras capturing the eagles presence at gut piles, people noticed more golden eagles. They got excited, started looking more frequently, and now we see a lot more eagles.

Right now, during their spring migration from early March through the first week in May, is the best and really the only chance for folks in northwest Wisconsin to see these big birds near home.

In the winter, some golden eagles hang out in the goat prairies of the Driftless Area of southwest Wisconsin and northeast Iowa, where they prey on wild turkeys, medium-sized mammals and carrion. Others spend time in the uplands of the Mississippi River corridor, the Ozarks and even the Gulf states.

During the summer, golden eagles breed in the Black Hills and western United States, but the ones who migrate through Wisconsin are heading to the Canadian Arctic to build their nests. Golden eagles are also found throughout Europe and Asia on the tundra, in boreal forests and in mountains. But as confirmed by Wisconsins recent breeding bird atlas, no golden eagles nest in Wisconsin.

On fall migration, golden eagles hit the shore of Lake Superior and follow it around to the west. Counters at Hawk Ridge in Duluth spot dozens in October and November, but the Northern Great Lakes Visitor Center is in Lake Superiors shadow.

Outside of this brief window of spring migration, golden eagles typically arent here.

So what about the dark eagles we see perched in white pines along our lakes and streams all summer long? Those are immature bald eagles who take four years to develop their white head and tail.

How can you tell what type of eagle youre seeing?

Season is your first criteria. Golden eagles arent here in the summer, while bald eagles of all ages are quite common. Habitat is another clue golden eagles hunt in the uplands and dont spend time around lakes and rivers like bald eagles do. Another place youll find bald and not golden eagles is eating roadkill along busy highways. Golden eagles do eat carrion, but they are more skittish and prefer to be on the backroads.

How about size?

Theres a popular myth that golden eagles are bigger than bald eagles. In fact, their weights and wingspans are similar, and both species exhibit sexual dimorphism in which females are larger than males. Golden eagles have smaller heads noticeable especially in flight.

There are variations in their feathers, too. Adult bald eagles have the classic white head and tail, of course. Immature bald eagles are mostly dark, with some white mottling.

If there is a big patch of white, it will be in their wing pits. In contrast, immature golden eagles have white patches on their wrists as you look up at them from below. While bald eagles hold their wings flat, golden eagles wings are angled up in a slight dihedral similar to a turkey vulture but without the vultures tipsy flight.

So when is the best time to see golden eagles in northwest Wisconsin?

Now! Just look up!

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'Tis the season to see golden eagles, population seems to be growing each year - Hudson Star Observer