Oceanic, alpine and grassland birds vulnerable to climate change: New Report
On March 10, the State of the Birds 2010 Report on Climate Change was released. Though this report was written about birds of the United States of America, many of the examples and conclusions are very relevant to Canada.
The report presents a gloomy picture for many species already facing threats from many other factors such as habitat loss, pollution, and invasive species. This report follows the 2009 State of the Birds Report describing how approximately a third of the 800 species that occur in the United States are in varying states of decline and imperilment.
“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 and other key habitat, the introduction of invasive species, and other impacts of human development”, United States’ Secretary of the Interior 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 towards extinction.”
The report is the product of a collaboration between federal and state wildlife agencies, and scientific and conservation organisations including partners from National Audubon Society (BirdLife in the U.S.), the American Bird Conservancy, Association of Fish and Wildlife Agencies, Cornell Lab of Ornithology, Klamath Bird Observatory, The National Fish and Wildlife Foundation, The Nature Conservancy, U.S.D.A. Forest Service, U.S. Fish and Wildlife Service, and the U.S. Geological Survey.
The report assessed the impact of climate change on each bird species, resulting in a classification of high, medium or low vulnerability. In the final analysis, specific groups of species appear much more vulnerable than others, due to one or a combination of the five following factors:
• migration status
• breeding habitat dependence
• ability to disperse
• highly specialized species
• reproductive potential
Most vulnerable were all 67 seabird species such as Murres, Albatroses, Puffins, and Petrels due to both threats to low-lying coastal breeding areas from flooding and alterations to food supplies caused by changes in ocean currents and ocean surface temperatures. Canada has large numbers of seabirds on Atlantic, Pacific and Arctic Coasts that share these vulnerable characteristics. Hundreds of thousands of Canadians are familiar with some of the enormous colonies of seabirds in places like Ile Bonaventure on the Gaspe Peninsula, or Cape St Mary’s in Newfoundland-Labrador, or have watched seabirds feeding from the Vancouver-Victoria ferries on Southern British Columbia.
A second group considered highly vulnerable to climate change are those species breeding in Arctic and Alpine regions. They are considered to have limited options for movement as they live in, and depend upon habitats in the coldest and highest locations. As these areas warm up, as they are expected to dramatically do, species such as Ivory gull and White-tailed Ptarmigan may suffer the consequences.
Grassland species are also believed to be vulnerable to climate change. As grasslands in the central basin of North America warm, they will also become more arid. Some species respond to the changing climatic and habitat conditions by shifting their ranges northward. However, much of the northern part of the grassland ecosystem in central North America has been converted to row crops that can not support most grassland bird species. In Canada, some grassland species that are likely already suffering the consequences from the combination of climate change and habitat conversion to industrialized agriculture include Spragues Pipit and Chestnut-collared Longspur. Many of the prairie potholes in southern Saskatchewan, south-western Manitoba, and south-eastern Alberta are also expected to dry up, threatening populations of the majority of waterfowl species that live in North America.
Most species in aridlands, wetlands, and forests were attributed relatively low vulnerability to climate change. However some species that occur in Canada including Bicknell’s Thrush, Whip-poor-will and Olive-sided Flycatcher may be particularly vulnerable due to habitat dependencies.
While painting a worrisome portrait of what could be in store for many species, the report does suggest many solutions through actions, planning and collaboration of individuals and organizations that can have positive impacts on bird populations and mitigate some of the impacts of climate change. Some of the examples include conserving carbon-rich forests and wetlands, managing coastal areas differently, and using incentives to avoid deforestation to reduce carbon emissions and encourage habitat protection or restoration.
While many examples of this report could apply to Canadian birds, it is time that a “State of the Birds” including an assessment of climate change impact on bird populations, was completed for Canadian birds to inform conservation planning, monitoring and research efforts here. Through the Migratory Bird Convention, the Convention on Biodiversity, and the Migratory Bird Convention Act, among other Canadian legislation, Canada has legal and ethical obligations to assure that its bird populations are protected and managed appropriately. In order to do this, we need a clear understanding of the status of our birds, as our friends and colleagues to the south of us have done.
Atlantic Puffins (Newfoundland) Shutterstock
Ivory Gull Simon Stirrup
Chestnut-collared+Longspur Al MacKeigan
Whip-poor-will Alan Woodhouse