Report: Climate change threatens hundreds of bird species
Summit County Correspondent
AUSTIN, Tex. – Climate change threatens to imperil hundreds of species of migratory birds, already under stress from habitat loss, invasive species and other environmental threats, according to a new report released by the U.S. Fish and Wildlife Service.
“For well over a century, migratory birds have faced stresses such as commercial hunting, loss of forests, the use of DDT and other pesticides, a loss of wetlands or other key habitat, the introduction of invasive species and other impacts of human development,” Interior Secretary Ken Salazar said. “Now they are facing a new threat – climate change – that could dramatically alter their habitat and food supply and push many species toward extinction.”
Already, a third of the U.S.’s 800 bird species are endangered, threatened or in significant decline, according to the agency.
“The State of the Birds: 2010 Report on Climate Change” is a result of a collaboration between the U.S. Fish and Wildlife Service and experts from the nation’s leading conservation organizations. The report warns that all birds in all habitats, including the Rocky Mountains, are affected.
In the Colorado Rockies, drier weather, unpredictable snowpack and timing changes in the seasonal emergence of insects are all key climate issues that pose threats to migratory birds.
Of particular concern is the black swift, a slender, black bird that spends its summers in the North American mountains and is thought to winter in western Mexico. Black swifts nest behind Colorado waterfalls in the summer.
“Loss of snowpack is a huge concern,” said Greg Butcher, director of bird conservation for the National Audubon Society and a member of the report’s science team. “Nesting sites might not be protected. The whole reason they nest behind waterfalls is to reduce access to predators.”
Further complicating matters is that the species forages for insects over alpine lakes. If insects emerge sooner than normal, the bird might miss out on meals necessary for the high-calorie demands of reproduction. Black swifts time their migration from the south according to changes in daylight hours, but insects emerge based on cues from increasing temperatures.
“There is a danger of missing the whole reproductive season. It’s going to be hard for a bird to arrive at the right time for nesting,” Butcher said.
High-alpine birds are also vulnerable to climate change. Birds like the ptarmigan and the brown-capped rosy-finch are at extreme risk, because the lower limit of their habitat is moving up mountain slopes, as warmer weather allows forests to creep to higher elevations.
“They need open, grassy tundra. If that gets taken over by woody vegetation, they’re in big trouble,” Butcher said.
Effects of warmer, drier weather
Species that depend on forested habitat will also feel pressure from warmer, drier weather, as the threats of forest fires and insect outbreaks increase.
Arid habitats within Colorado and elsewhere are at great risk from climate change, as they too, become warmer and drier, according to the report. One expected result is that tree cover will increase in areas now dominated by shrubs and sagebrush – of particular concern to the declining greater sage grouse populations in the state.
In releasing the report, Salazar cited new efforts by the Obama Administration and the Department of the Interior to address climate change. Last week, the Interior Department opened the first of eight new regional climate centers that will bring together scientists to research climate change impacts, design adaptation strategies and educate the public.
“Just as they did in 1962 when Rachel Carson published ‘Silent Spring,’ our migratory birds are sending us a message about the health of our planet,” Salazar said. “That is why – for the first time ever – the Department of the Interior has deployed a coordinated strategy to plan for and respond to the impacts of climate change on the resources we manage.”
Julie Sutor can be reached at (970) 668-4630 or firstname.lastname@example.org.