(Transcript of For the Birds program from May 26, 2010)
A treasured, lovely sparkle of animated color in the north woods is also one of the most rapidly declining warblers in the United States. The Golden-winged Warbler is an eye-catching bird, with bright golden yellow patches on the wings and crown contrasting beautifully with the bright white underside, soft gray back, and bold black throat and eye patch. Its soft, buzzy song is hard to hear but lovely in a quiet, subtle way.
Golden-winged Warblers are closely associated with second growth aspen forests, and so were once common in the Midwest. But for the past 40 years they’ve declined an average of 2.8% per year according to Breeding Bird Survey data, and that rate is accelerating. They’ve completely disappeared from Iowa, Illinois, Indiana, and Ohio, and are now restricted to a fraction of their former range in Wisconsin and Michigan. Minnesota has more remaining than any other state, but even here they’re now restricted to the central part of the state west of Duluth and Minneapolis. From1994–2003, in the US Fish and Wildlife Service Region 3, which contains Minnesota, Wisconsin, and Michigan, they’ve declined by 9 percent annually, and they’ve declined 11.3% annually in Ontario.
This kind of dramatic decline was exactly the kind of situation the Endangered Species Act was supposed to help reverse, but for decades it’s been virtually impossible for species to be listed so they can get this kind of federal help. The Golden-winged Warbler is considered a “species of management concern” in the United States, but this doesn’t give it anywhere near the level of protection that being listed as Endangered or Threatened would do. Why is this bird in so much trouble in the first place? Golden-wings have a fairly small wintering range in Central America, where deforestation and development exact a heavy toll. Individuals are killed on migration, especially at hazards such as lighted communications towers and tall buildings. And in more southern parts of their range, their close relative the Blue-winged Warbler has been out-competing them. But one of the main issues in the upper Midwest and Canada involves their breeding habitat. The secondary aspen forests they require are the first successional stage after natural disturbances and logging, but a great many of the areas they formerly nested in have been lost to development. When I did my annual US Fish and Wildlife Service Mourning Dove route this year, for the 25th straight year, I was dismayed to see yet more houses and businesses popping up in what had been forest and wetland. Development has been great news for Canada Geese, white-tailed deer, Wild Turkeys, and other species that have adapted to lawns and ornamental plants, but is not so good for species that require genuine wildness.
If Golden-winged Warblers are in serious decline, they’re still out there. I’ve been teaching an Elderhostel this week at Trees for Tomorrow in Eagle River, Wisconsin. We went out to a spot we check every year, and found singing males exactly where we always do. It’s such a thrill to see them, and gratifying to help people get a good look at a bird they’d never seen before, but it’s also sad that this lovely little bird no longer can be found in the areas in Illinois and southern Wisconsin where some of these people live—areas where Golden-winged Warblers once thrived. One of the males was cooperative enough to give me some lovely photos. I think he’s the same male I photographed last summer in the same spot. I hope I’ll be able to find him and his successors in this lovely place for many, many years to come.