New, Growing Concern for Bald Eagles
Bald is Beautiful
Especially as Silent Sporters, you probably couldn’t imagine a world and the outdoors you enjoy without bald eagles. Magnificent and majestic creatures, eagles have wingspans reaching eight feet, soaring silently over the frozen Mississippi River, scanning the waters for prey. Then that shrill scream rends the air as they dive toward the icy water, talons outstretched, now clutching a wriggling fish as those powerful wings pump, rising into the air, razor sharp talons and beak now digging into dinner as the eagle perches high in a tree. An awesome and somewhat fearful sight.
And to think that we, as a nation, nearly lost this incredible symbol.
First Victory, But Then …
As a youngster in the early 1970s, I remember my Weekly Reader telling me that our national symbol was endangered and could become extinct because of the chemicals used to rid farms of bugs. Luckily for us, a hue and cry from environmentalists went up and we the people joined in, helping to get DDT banned from use. The chemical itself didn’t kill birds. Rather, it was the effect it had on critters further down the food chain. By the time an eagle ate a fish, that fish had such concentrated levels of DDT that, when eagles laid eggs, the shells were thinned due to too little calcium, preventing developing chicks from reaching maturity before the shell cracked, killing the babies inside. No shells, no baby eagles.
Fast forward three decades. One morning, I’m driving along a back road on my way to my teaching job a mile or two west of the Mississippi River, outside of LeClaire, Iowa, doing a little scenery scanning as I drive. I gasped with surprise as I saw a bald eagle sitting in a tree by the road. I knew they were no longer endangered, but I never thought to see one leisurely perched in a tree on my drive to school. These days in winter, I’ve even driven over the Mississippi River from Iowa to Illinois and have had opportunities to see dozens of eagles in trees near the lock and dam, where they sit near open water, waiting for their next meal.
With their populations substantially recovered since the 1980s, bald eagle watching has become a winter draw to the Quad Cities (Davenport and Bettendorf, Iowa, and Rock Island and Moline, Illinois). In January, we have had an annual event over the past ten years, Bald Eagle Days, originally founded by the Quad Cities Conservation Alliance, where people flock to learn about our national bird and other environmental wonders of the upper Mississippi Valley watershed. Raptor groups bring birds to educate the public about various species who live in the area, including bald eagles.
Endangered species success story, right? Well, maybe.
While banning DDT eliminated a specific threat to bald eagles, when it comes to the environment and conservation, there really is no one and done. Just because one chemical is gone, other threats still exist. According to Kelly McKay, a wildlife biologist and consultant from Hampton, Illinois, who is also the Quad Cities organizer of the yearly Audubon Christmas Bird Count (www.audubon.org/conservation/science/christmas-bird-count), and also a strong force in the National Midwinter Bald Eagle Survey (gis.nacse.org/eagles/) sponsored by the Army Corps of Engineers, the number of eagles wintering on the river has begun dropping over the past decade.
McKay said part of this drop may be due to milder winters up north, such as in Canada where eagles spend their summer months. However, eagles are also wintering farther inland to find more food. Although eagles mostly eat fish, they also eat carrion, such as dead livestock or winter-killed animals such as rabbits or deer or gut piles left by hunters. With food sources still out there, problem solved, right?
Not Quite Solved
Because eagles are mostly fish eaters, and McKay’s data has noted that the numbers of one specific fish seem to be dropping alarmingly, concern continues. During the Midwinter Bald Eagle Survey, McKay travels an 80-mile stretch of the Mississippi River from Clinton, Iowa, to Keithsburg, Illinois, over the course of several days in January. As he notes numbers of eagles, he has also taken note of an extreme drop in numbers of the biggest source of the eagle’s diet, at least in this area: the gizzard shad.
This small, silvery fish often suffers from winter kill in vast numbers due to the river’s icing over. According to McKay, in some lock chambers, he would see up to 10,000 dead shad. While this may sound bad, it’s actually no cause for alarm. Eagles would happily feast on these dead fish, and it was a lot easier for them to find food this way. Accordingly, the eagles actually benefitted from winter-killed shad.
But in the past two decades, where McKay previously saw huge numbers of dead shad, he is seeing almost none. In some places, numbers have gone from 10,000 to less than a dozen. This may be the proverbial canary-in-the-coal-mine warning. In this case, what has happened to the shad?
There has been a bit of a debate between McKay and a now-retired fisheries biologist from Bellevue, Iowa, who feels the numbers of shad are fine because the count taken in Bellevue has not changed much over the years. However, the Bellevue count occurs in the summer. By January, something clearly had changed.
McKay has some ideas, but cannot be certain. His biggest suspect? Zebra mussels. These freshwater mussels, an invasive species in the US, clean water by eating enormous amounts of zooplankton and phytoplankton. Notably, these small creatures are also the shad’s food source. And once invasive Zebra mussels move in, it’s extremely difficult to get rid of them. It’s hard to know for sure without research into the problem. According to McKay, the needed research would have to happen the same way we learned about DDT’s impact on eagles decades ago: citizen scientists.
History Showing the Way
In the 1960s and ’70s, a Quad City native named Elton Fawks was fascinated by and concerned about bald eagles. He used to travel a set route, counting eagles and recording data, and he came up with a theory: Some kind of chemical might be harming the eagles. Although he was not a trained biologist, his interest, concern, and persistence were enough to raise the alarm and cause scientists to look into the issue. The result: the eventual banning of DDT in 1972. Fawks also caught the interest of a teenager named Kelly McKay, who became friends with Fawks as he learned about bald eagles from him.
Today, McKay, whose master’s thesis dealt with winter bald eagle populations and factors influencing their distribution, is now a trained biologist and a consultant, training citizen scientists through R.E.A.P (Resource Enhancement and Protection) workshops in Iowa. Over the past two years, in 26 Iowa counties, McKay has been conducting 100 workshops entitled “Building Better Birders and Citizen Scientists.”
He feels that having more people trained in observing the environment and recording data, we might figure out what is happening to the eagle’s food source, the gizzard shad. And maybe, if we can find out why it’s happening, we can figure out how to turn this around, just like Elton Fawks helped to do with DDT in the 1970s.
The next time you take out a dollar bill, look closely at the eagle on the back and consider where our country would be without that majestic symbol. Now think about how you, as a citizen and Silent Sporter, could help play a role in helping to work toward securing the future for the bald eagle, who really is more than just a symbol. Wouldn’t that be a wonderful result to this chapter of the story of the bald eagle?
Editor’s Note: JK Broders is a writer, teacher, auctioneer, and, get this: a two-time Jeopardy champion! She lives in Davenport, Iowa, and has a great interest in the animals and environments of the upper Mississippi Valley. She likes to hike, bike, and kayak in order to view nature up close. When not teaching 7th grade social studies, you can find her reading, writing, or gardening with her husband, Ed, and her two cats, Pouncer and Trouble.