Laura Erickson's For the Birds

Wednesday, September 10, 2014

Audubon's Climate Change Report

Common Loon

I’ve been looking forward to September 9 for months—it was the day the 2014 State of the Birds report was due to come out. This is the fifth edition of this annual report, put together by a large group of non-profits, such as the Cornell Lab of Ornithology, the American Bird Conservancy, Audubon, and Ducks Unlimited, working with government agencies such as the U.S. Fish and Wildlife Service, the U.S. Forest Service, the National Park Service, and  Environment Canada. I got to help with the first issue, released in 2009 when I was serving as the science editor at the Cornell Lab of Ornithology, and know how careful the group is at reaching its conclusions. 

The report this time has some disturbing findings. Their “Watch List” of vulnerable species in the United States and Canada, each meeting their criteria of a combination of high rate of population decline, small population size, small geographic range, and significant future threats to sustainable populations, includes 230 species.

Baltimore Oriole

First thing in the morning on September 9, my email box became inundated with questions from people about the predicted loss, by the end of this century, of nesting loons in Minnesota and Baltimore Orioles in Maryland, and naturally I assumed they were referring to the State of the Birds report. But it turns out Audubon chose the same day to release a completely separate Climate Report

Audubon put together a comprehensive study, using current models of how the changing climate is and will continue to change habitat, to see how climate change could affect the ranges of 588 North American bird species. Their models indicate that 314 species will lose more than 50 percent of their current range by 2080. Of them, 126 species are projected to lose more than 50 percent of their current range by 2050 if the changes due to global warming continue at their current pace.

Common Loon

To get the attention of the media, Audubon used two extremely popular state birds—the Baltimore Oriole and the loon—as their poster children for the report. And almost all the people writing me were asking about our beloved loon. Current projections by Audubon for the Common Loon indicate that by 2080, the breeding range will retract as water temperatures rise. Loons require extremely clear water for catching fish, and the algae growth associated with warmer temperatures will little by little force breeding loons out of Minnesota and Wisconsin. Unfortunately, loons already breed at the farthest northern reaches of the continent, so as they lose ground in the southern part of their range, they can’t expand to the north. By 2080, they’re expected to have only 44 percent of their breeding range remaining.

Audubon used Christmas Bird Count data to indicate winter ranges of birds, making the situation for loons sound even direr, because Audubon predictions indicate that loons will lose 80 percent of their winter range. But really, loons are often still migrating during much of the Christmas Bird Count period—the vast majority of our loons winter on salt water in the Atlantic or the Gulf of Mexico. Of course, that situation is also worrisome, because of major changes in fish populations as ocean water temperatures rise.

The Audubon projections for Baltimore Orioles do, indeed, show the breeding range moving north and out of Maryland, but nevertheless, Baltimore Orioles are projected to enjoy an overall range increase, as cottonwoods retract from a small area but expand into what is now boreal forest. Through 2080, Audubon projects that Baltimore Orioles will enjoy a 76 percent increase in suitable breeding range.

That increase will come at the expense of birds depending on what is now boreal forest. Our beloved Northern Hawk Owl—a wonderfully confiding and charismatic visitor in winter and occasional breeder in the bog country just north of Duluth—is among the 30 species threatened with the loss of more than 90 percent of their current range by 2050.

What can we do to help? Conserving energy will not only reduce the carbon gases we send into the atmosphere but reduce a whole suite of other dangers to birds caused by extracting, transporting, and burning fossil fuels. It’s simply the right thing to do.

Northern Hawk Owl