David Yarnold and Gary Langham
By David Yarnold and Gary Langham
Maryland could lose the flashy orange-and-black Baltimore oriole — its state bird and the mascot of its Major League Baseball team — before the end of this century because of global warming.
The common loon, Minnesota’s state bird and an iconic species across much of the northern United States, may not be able to raise its young anywhere in the contiguous 48 states by 2080. The bobolink, a charismatic grassland songbird, could be pushed into the boreal forests of Canada, where it would be unlikely to survive. Washington, DC’s official bird, the wood thrush, could move out of town.
And the list goes on. The roseate spoonbill, the sandhill crane, the rufous hummingbird and the scarlet tanager are all threatened by global warming.
Yesterday, National Audubon Society scientists released the largest and most comprehensive examination of birds and climate change ever undertaken in North America. The results are alarming: Of the 588 species we studied, 314 will lose 50 percent or more of their current ranges by 2080 unless the greenhouse-gas emissions that cause global warming are significantly reduced. More than half our birds are threatened by global warming, and many will be driven toward extinction if we do not act.
Over the past seven years, our team has analysed more than 30 years of bird observations from the North American Breeding Bird Survey, the Audubon Christmas Bird Count and data from leading climatologists in the United States and Canada. This intensive analysis gives us an unprecedented ability to project where birds are most likely — and unlikely — to survive in the future.
Imagine: Within two generations, nine states could discover that their state birds are at risk. Our national emblem, the bald eagle, brought back from the brink of extinction when we banned the pesticide DDT, faces the prospect of a nearly 75 percent decrease in its current range in the next 65 years. The graceful white trumpeter swan, the friendly backyard brown-headed nuthatch and the coastal black skimmer could lose more than 99 percent of their current ranges. Dozens more species face similarly shocking declines.
Dire as all this sounds, the reality is likely worse. We don’t yet have data for Central and South America, where many of our birds spend the winter. Some birds aren’t well surveyed and couldn’t be included in our study, and we took a cautious approach to processing the data. If we know for sure today that half our birds are at risk, it’s likely that many more are as well.
We examined the fundamental relationship between birds and climate variables, such as seasonal precipitation and temperature fluctuations. Every species has a tolerance zone for climate conditions. For example, humans would not survive long in Antarctica without appropriate gear or supplies. Similarly, if the climate gets too hot, too cold, too wet or too dry, birds will be forced to leave their homes. Some species will be able to colonise in new areas as the climate in those places changes. But many birds will simply run out of suitable places to find food and reproduce as they push farther north, move to higher elevations or encounter unfamiliar habitats or new competitors. WP-BLOOMBERG
By David Yarnold and Gary Langham
Maryland could lose the flashy orange-and-black Baltimore oriole — its state bird and the mascot of its Major League Baseball team — before the end of this century because of global warming.
The common loon, Minnesota’s state bird and an iconic species across much of the northern United States, may not be able to raise its young anywhere in the contiguous 48 states by 2080. The bobolink, a charismatic grassland songbird, could be pushed into the boreal forests of Canada, where it would be unlikely to survive. Washington, DC’s official bird, the wood thrush, could move out of town.
And the list goes on. The roseate spoonbill, the sandhill crane, the rufous hummingbird and the scarlet tanager are all threatened by global warming.
Yesterday, National Audubon Society scientists released the largest and most comprehensive examination of birds and climate change ever undertaken in North America. The results are alarming: Of the 588 species we studied, 314 will lose 50 percent or more of their current ranges by 2080 unless the greenhouse-gas emissions that cause global warming are significantly reduced. More than half our birds are threatened by global warming, and many will be driven toward extinction if we do not act.
Over the past seven years, our team has analysed more than 30 years of bird observations from the North American Breeding Bird Survey, the Audubon Christmas Bird Count and data from leading climatologists in the United States and Canada. This intensive analysis gives us an unprecedented ability to project where birds are most likely — and unlikely — to survive in the future.
Imagine: Within two generations, nine states could discover that their state birds are at risk. Our national emblem, the bald eagle, brought back from the brink of extinction when we banned the pesticide DDT, faces the prospect of a nearly 75 percent decrease in its current range in the next 65 years. The graceful white trumpeter swan, the friendly backyard brown-headed nuthatch and the coastal black skimmer could lose more than 99 percent of their current ranges. Dozens more species face similarly shocking declines.
Dire as all this sounds, the reality is likely worse. We don’t yet have data for Central and South America, where many of our birds spend the winter. Some birds aren’t well surveyed and couldn’t be included in our study, and we took a cautious approach to processing the data. If we know for sure today that half our birds are at risk, it’s likely that many more are as well.
We examined the fundamental relationship between birds and climate variables, such as seasonal precipitation and temperature fluctuations. Every species has a tolerance zone for climate conditions. For example, humans would not survive long in Antarctica without appropriate gear or supplies. Similarly, if the climate gets too hot, too cold, too wet or too dry, birds will be forced to leave their homes. Some species will be able to colonise in new areas as the climate in those places changes. But many birds will simply run out of suitable places to find food and reproduce as they push farther north, move to higher elevations or encounter unfamiliar habitats or new competitors. WP-BLOOMBERG
