A new study released today by the National Audubon Society reveals a comprehensive look at how climate change is projected to affect bird species across the country.
Nils Warnock, Audubon Alaska's Executive Director said, "Our world's climate is changing and results of this major study reveal that many North American birds will be losers if we do not begin to implement change. There are those of us who like to look at birds and some of us like to hunt birds, but we all appreciate these amazing creatures. Likewise, we can all help by taking notice of this climate challenge and by beginning to at least take small steps towards positive change."
Using data from Audubon's annual Christmas Bird Count (one of the longest running citizen science projects in the world) and the federal Breeding Bird Survey, Audubon's science team looked at the climate zones in which different bird species live today and projected where those zones would be in the future. The beginning point is species distribution in the year 2000, with projections for 2020, 2050, and 2080. The result is a picture of how the range for each bird species in the study will possibly expand, shift, or shrink. Species at risk are then categorized as:
- Climate threatened: the species is projected to lose more than 50 percent of its current range by 2080.
- Climate endangered: the species is projected to lose more than 50 percent of its current range by 2050.
How could this affect birds that we see in Alaska? One example is the Trumpeter Swan. After decades of low numbers, dropping to less than 100 birds in the Lower 48 during the 1930s, the Trumpeter Swan was removed from Audubon's 2010 Alaska WatchList of declining and vulnerable bird species because the population has been increasing steadily over the last 30 years. Swans are highly dependent on wetlands, so drying out of arctic and boreal wetlands due to climate change could reverse the swans' positive trend. By looking ahead and taking action now, we can help the largest of North America's waterfowl while the populations are still strong and resilient.
Alaskans are familiar with the reality of climate change, from retreating Arctic sea ice and coastal erosion to changing permafrost levels, increased fires, and bark beetle infestations. This study highlights some of the impacts climate change in the Lower 48 may have on our ecosystems by identifying a number of Alaska-nesting bird species threatened by changing climate on their wintering grounds further south.
One example is the Rufous Hummingbird, the only hummingbird species to regularly nest in Alaska. These feisty birds nest in Southeast Alaska up through the Kenai Peninsula with small numbers in Anchorage. The climate model projects that Rufous Hummingbirds will lose their current wintering range in the U.S. by 2080, although gains are possible to the north.
This study also points us in the direction of future studies to fill in gaps on species this study does not focus on. For instance, more than 87 percent of the seabirds in the U.S. nest along Alaska's shores in the summer, creating some Alaska-specific concerns about how climate change will affect seabirds. Some species, such as Ivory Gulls and Spectacled Eiders, are associated with sea ice. The average sea ice extent in the Arctic Ocean in September has decreased by 11.5% per decade over the past 30 years. Late summers could be nearly ice-free as early as about the 2040s. We need to start asking, what does this loss mean for these key Arctic inhabitants?
The National Audubon Society study, backed by strong science, highlights how global change may affect our bird populations. The next step is for people to take action to change the direction of climate change for the birds they see at home.
Now in its second century, Audubon is dedicated to protecting birds and other wildlife and the habitat that supports them. Our national network of community-based nature centers and chapters, scientific and educational programs, and advocacy on behalf of areas sustaining important bird populations, engage millions of people of all ages and backgrounds in conservation. www.audubon.org