BLANE KLEMEK OUTDOORS: The bald eagle has made an impressive comeback
Bald eagles, abundant at one time and nearly extirpated at another, are now recovered and doing exceedingly well as their future continues to shine.
Minnesota’s bald eagle population continues to grow, and that’s a good thing. Recent sightings of bald eagles throughout the Northland are a sure sign that spring is imminent.
Not only that, but the frequent observations also tell a success story. Minnesota’s eagle population—and eagle populations throughout North America—are growing and expanding.
Becoming increasingly more popular from all corners of the nation is the proliferation of so-called “eagle cams.” These cameras, strategically positioned to monitor the activities of nesting eagles, are commonplace nowadays. Quick internet searches reveals websites everywhere that you can monitor nesting eagles, including here at home.
The Minnesota Department of Natural Resources “EagleCam” located on DNR’s website monitors a nesting pair in real-time, 24/7. It can be found online at: www.dnr.state.mn.us/features/webcams/eaglecam/index.html.
The success story of America’s bald eagle population recovery cannot begin without first recognizing how imperiled the population once was. In the early 1960s, biologists estimated that the breeding population in the continental United States was just 417 nesting pairs. At the time, Minnesota had only around 50 nesting pairs of bald eagles.
But by 1972, the pesticide DDT was banned from use along with, a year later, the passage of arguably the most important and impactful wildlife-related legislative act ever: the Endangered Species Act. Henceforth, the bald eagle’s slow climb to recovery began in earnest.
Today, after being officially removed from the endangered species list, the population of bald eagles in the lower 48 states, including Washington D.C., is over 71,400 nesting pairs.
And though bald eagles were federally delisted in 2007, the species is well protected under many laws that include the Bald and Golden Eagle Protection Act, the Migratory Bird Treaty Act, and the Lacey Act.
Just a short time ago while driving past La Salle Lake State Recreation Area, I spotted the resident pair once again. One of the birds was perched in a tree while its mate was standing on top of the snow in the ditch and feeding on an animal carcass.
The sight got me thinking about the importance of carrion to eagles in late winter and early spring. While fish is their preferred food, bald eagles scavenge for many of their meals, especially when prey is scarce. It’s very common to see bald eagles along our roadways feeding on deer carcasses and other carrion.
Interestingly, the diagnostic feature of bald eagles — the white head and white tail feathers — don’t become visible until the bird reaches about 4 or 5 years old. Juveniles are brown and mottled with white plumage throughout and are often mistakenly identified as mature golden eagles. As a result, it’s often reported that golden eagles have been observed when in fact it was merely a juvenile bald eagle.
Adult bald eagles form lifelong pair bonds. Able to reach ages of 30 years old in the wild, a mated pair of eagles can raise many offspring over their lifetime.
Returning to the same nest every spring, a pair will continue to add sticks and nest-building materials to their nest year after year. If the nest or tree becomes damaged or destroyed, the nesting pair will build a new nest in the same nesting territory if a suitable tree exists.
The size of a bald eagle nest is impressive. Because a nesting pair adds materials to the nest each year, a nest can reach weights of up to two tons and can obtain a diameter of nine to ten feet. It takes a strong tree to support such a nest.
Nests are usually built in large white pine trees and cottonwood trees near lakes and rivers. In places where trees are unavailable or unsuitable, bald eagles are known to build their nests on the ground near cliffs, rivers and other water sources.
Bald eagles, abundant at one time and nearly extirpated at another, are now recovered and doing exceedingly well as their future continues to shine. Bald eagles are nesting in areas throughout their historical range everywhere, including here at home, as we get out and enjoy the great outdoors.
Blane Klemek is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.