I love that we can watch these bald eagles, what a wonderful resource.
from the mn DNR We’ve come a long way, baby’
Compared to the excitement when our eagles produced their first egg on Jan. 28, the past four weeks have been a bit on the mundane side as the pair take turns sitting on their three eggs to keep them warm. Fifty or 60 years ago, that routine act of incubation played a significant role in bald eagles’ decline to where, by 1963, fewer than 500 nesting pairs of America’s national bird remained. It’s a tale that illustrates the unintended consequences of technology, and the importance of proactive environmental policy.
In the hopeful years following WWII, when science seemed to hold forth solutions for all sorts of perennial problems, the pesticide DDT emerged as a potential savior in the fight against mosquito-borne diseases and insect pests in crop and livestock production. But as use grew, it became evident that this “solution” also created its own set of serious environmental problems.
DDT and its residues washed into waterways, where they accumulated in aquatic plants and fish. Bald eagles ate the fish contaminated with DDT, and the chemical interfered with the ability of the birds to produce strong eggshells. As a result, their eggs had shells so thin that they often broke under the eagles’ own weight as they sat on them during incubation. DDT also caused other environmental problems, and was later found to cause cancer in humans.
After the 1962 publication of Rachel Carson’s “Silent Spring” drew national attention to the toxic effects of DDT and other pesticides, it took another 10 years before the use of DDT was banned by the newly formed Environmental Protection Agency in 1972. Following enactment of the Endangered Species Act of 1973, bald eagles were added to the federal list of threatened and endangered species in 1978. DDT wasn’t the only problem facing eagles; their numbers also suffered from habitat destruction and illegal shooting. But the ban against DDT’s use was an important first step on the road to recovery for bald eagles, which now number over 10,000 breeding pairs in the lower 48 states, with Minnesota home to the most.
The bald eagle’s comeback, to where it now has been removed from the endangered species list, was the product of concerted federal and state policies rooted in sound science and citizen action. Those things are just as important now, as eagles and other wildlife face challenges arising from lead poisoning, new types of pesticides like neonicotinoids that cause problems for pollinators, global warming and other threats.
Countdown to the hatch
Fortunately, our eagles don’t have to worry about crushing thin-shelled eggs. They’ve been diligently incubating their eggs for nearly a month now. It shouldn’t be long before we have chicks! Allowing 35 days, the first-laid egg could hatch as soon as March 4 – just a week from this Saturday. Will you be watching when it happens?
Small investments, big results
Minnesota’s Nongame Wildlife Program has been instrumental in the national recovery of bald eagles and other species. When the program began 40 years ago, the U.S. had few bald eagles left. Because Minnesota’s population was healthy and growing, the Nongame Wildlife Program arranged to donate 55 chicks to New York, Tennessee, Georgia, Missouri and Kentucky to assist bald eagle recovery in those states. The chicks to be donated were removed only from Minnesota nests that had two or more healthy chicks in them. It’s a great example of how a small investment played a big role, helping our national bird recover from near extinction.
Won’t you consider a small investment in your Nongame Wildlife Program to help us help wildlife? Consider it a 40th birthday gift to all the wild critters that benefit from our efforts! Without your ongoing interest and investment, we would be unable to help bald eagles or any other species.