Global Warming Could Displace State Birds

By Cat Lazaroff

WASHINGTON, DC, March 11, 2002 (ENS) - Global warming could shift the ranges of many songbirds - leaving some U.S. states without their official state birds, warns a new study. Climate models project that the range of some state birds could shrink or shift entirely outside of the states they represent, including Baltimore orioles in Maryland, purple finches in New Hampshire, and California quail in California.


The American goldfinch, state bird of Iowa and Washington, could dwindle or even vanish in up to 33 states, the report suggests. (Photo by J.R. Woodward, courtesy Cornell Lab of Ornithology)
The nation's more than 63 million birdwatchers could also feel the impact of climate change, because it is likely to cause some songbird species to decline or disappear from their current summer ranges, finds the study released by the American Bird Conservancy (ABC) and the National Wildlife Federation (NWF).

"Imagine Baltimore without the Baltimore oriole," said NWF president Mark Van Putten. "Left unchecked, global warming could cause the birds we love to watch and even celebrate on state emblems to disappear from places they've lived for eons."

A total of 1,111 birds - 11 percent of the world's bird species - are considered to be at risk, and as many as 200 of these may disappear within the next 20 years. The United States ranks among the top 10 countries in terms of the total number of vulnerable bird species, according to the report, titled "The Birdwatcher's Guide to Global Warming."


A female Baltimore oriole, Maryland's state bird, visits her carefully crafted nest. (Photo courtesy Cornell Lab of Ornithology)
The report shows that global warming is already shifting the ranges of some songbirds in the U.S., altering their migration behavior and habitat, and perhaps diminishing some species' ability to survive. Not only the birds are affected - other wildlife sharing the birds' habitat is also reacting to the changing climate.

"It is not just the affection we feel toward birds driving our concern," said ABC president George Fenwick. "Birds are integral parts of virtually every ecosystem and provide enormous economic benefits through insect and rodent control, seed dispersal and pollination."

"Every migratory bird species has a critical job in its ecosystem and that job could remain incomplete if global climate change causes a species to disappear," added Van Putten. "This may trigger a dangerous domino effect for other plants and animals sharing its habitat."

The eastern midwest and Great Lakes regions could be the hardest hit, with up to a 30 percent net loss in the number of neotropical migrant species summering in the region. This includes species such as olive-sided flycatchers, solitary vireos and Cape May warblers, which play an important role in controlling insect pest populations in forests and agricultural areas.


Wintering in southern Mexico, Guatemala, Honduras and Nicaragua, the endangered golden-cheeked warbler may migrate across numerous borders to get to its breeding grounds in Texas (Photos courtesy USFWS)
As many as 33 states could see a significant reduction in American goldfinches in the summer. Some migratory bird species, such as the endangered golden-cheeked warbler in Texas, could face extinction as a result of global climate change.

"The potential impacts of climate change aren't happening in a vacuum. They have to be considered in the context of how they may act in concert with other well established population stresses such as habitat conversion, pollution and invasive species," explained ABC scientist Jeff Price, PhD, whose research was used in the study.

"The combination of these stresses is likely to prove to be the greatest challenge to wildlife, and wildlife conservation, in the 21st century," added Price. "Because anticipation of changes improves the ability to manage, it is important to understand as much as possible about the responses of animals to a changing climate."

Like many plants and animals, birds' life cycles and behavior are linked to the changing seasons, the report notes. For neotropical migrant species, including many of the warblers, vireos and other songbirds that breed in the U.S. and winter in tropical climes, changes in weather help signal when they should begin their long flights south in the fall and north in the spring.


New Hampshire's state bird, the purple finch, could become rare due to global warming. (Photo by W.A. Paff, courtesy Cornell Lab of Ornithology)
As the climate shifts, birds may have to try to shift their patterns as well, and many may end up out of synch with crucial aspects of their lives, including limited food sources like horseshoe crab eggs or blooming flowers, available only for a short period of time.

Another part of the problem lies in how climate change is likely to alter the birds' habitat. A report completed in 2000 by the U.S. Global Change Research Program concluded that some vulnerable systems such as alpine meadows in the Rocky Mountains and coastal wetlands and estuaries could disappear as global warming continues. In the Gulf Coast and mid-Atlantic regions, sea level rise could destroy habitat for migratory shorebirds and lead to flooding, erosion and property damage.

Several native species of trees may no longer be able to grow in some areas as summers become warmer, threatening the birds that rely on the trees for food and shelter.

Climate models project that average surface temperatures will rise an additional 2.5 to 10.4 degrees Fahrenheit by 2100 - more than ten times faster than what has been the average rate of natural sustained global temperature change since the last ice age, the report notes.

house sparrow

The aggressive house sparrow, introduced from Europe, has already outcompeted many native species for food and habitat, and could gain further ground due to the warming climate. (All photos courtesy Cornell Lab of Orthithology)
The report's authors say their findings underscore the immediate need to reduce greenhouse gas emissions generated from the use of fossil fuels such as coal in power plants and gas in cars. A plan released last month by the Bush administration would use voluntary agreements to slow U.S. emissions of carbon dioxide, but critics say the plan would lead to no net reductions in emissions, and could allow emissions to increase.

Resource managers and other wildlife professionals must begin to take climate change into consideration when they work to conserve species and habitat, the authors added. Climate change may act in concert with other well established population stresses such as habitat conversion, pollution and invasive species.

The report is available at: