For the Birds Radio Program: Declining Numbers
Laura talks about various causes for declining numbers of birds, and how hard it is to quantify what has been lost.
Transcript
I spent several days in Ohio this past May, at a major migration magnet called the Magee Marsh. Birds coursing northward are stopped by Lake Erie. They follow the shoreline along, their numbers increasing as they reach the western end of the lake at Magee. Magee is also near one of the ferry launch docks where Americans embark when headed to an even more famous migration magnet on the Canadian side, Point Pelee, Ontario.
I had a thrilling time at Magee, getting up close and personal to an excellent variety of warblers and other Neotropical migrants. I took thousands of photographs. One man was even getting close-ups of Black-throated Green Warblers through his cell phone.
This was the first time I’d visited Magee, and with the fun I was having, it was easy to ignore concerns voiced by people who’d been coming to the marsh for decades. They universally complained that this year’s migration was way down from previous years, noting that over the years, both the numbers of individuals and the numbers of days with huge numbers of birds have dwindled. What seems splendid to someone new there is a shadow of what it once was. Although I was never at the Magee Marsh during its amazing heyday, in the late 70s and early 80s I did get to witness some darned impressive migrations right where I happened to be, in southern Michigan and then southern Wisconsin. Already at that time some ornithologists and older birders were complaining about declines in birds, but having never noticed birds at all before 1975, it seemed thrilling to me to see so many. When I moved to Duluth in 1981, I could count on seeing a host of warblers and thrushes in my own backyard virtually every day in May. Now only a few species appear each year, and on only a handful of days.
An ornithologist named Sidney Gauthreaux learned how to read radar data, including the kind of radar used to detect weather patterns, to measure migratory bird movements. He discovered from archived radar data that during the 1960s, a significant migration occurred over the Gulf of Mexico on 95% of all nights that had favorable weather conditions. By the late 1980s, a significant migration occurred in the same area on only 44% of all nights with favorable conditions—about a 55% decline in migratory movements. Breeding bird surveys and radar data indicate that this trend is continuing, even as a handful of species, such as Canada Geese and American Robins, increase.
This week I received a letter from Country Today reader Michael Riegert, who has been surveying the same area near Medford for much of the past 30 years. He’s noticed a steady decline in Neotropical migrants such as Nashville and Yellow-rumped Warblers, Hermit Thrushes, Winter Wrens, and Yellow-bellied Flycatchers. This year this avian community has essentially crashed. He added that two friends, one near him and one in northeastern Wisconsin, are finding the same thing. I’ve also heard from many Minnesota and Wisconsin birders this year concerned with declines of hummingbirds.
Sadly, young birders who happen to get out on one of the few good migration days will never know how very much we’ve lost, and us older people who do remember would be fools to not take what enjoyment we can when we do see splendid birds. But a huge part of our natural heritage has been squandered, and young birders will never know to miss it. The ultimate question is whether anyone at all cares enough to do anything about it.