Bird Extinctions Baltimore Without Orioles
Maryland's Baltimore orioles, which have been declining due to habitat loss for many years, could vanish altogether late in the twenty-first century due to changes in migration patterns strongly influenced by a warming climate. A study by the National Wildlife Federation and the American Bird Conservancy "suggests that the effects of global warming may be robbing Maryland and a half-dozen other states of an important piece of their heritage by hastening the departure of their state birds" (Pianin, 2002, A-3).
The report said that Earth's rising temperature "is already shifting songbird ranges, altering migration behavior and perhaps diminishing some species' ability to survive" (Pianin, 2002, A-3). Iowa and Washington State may lose the American goldfinch, as New Hampshire's purple finch could become a historical relic. California could lose the California quails, Massachusetts' black-capped chickadee may vanish, and Georgia could lose its brown thrasher (Pianin, 2002, A-3).
The life cycle of the oriole and other birds is tied closely to weather patterns that are changing with general warming. Seasonal changes in weather patterns tell the birds when they should begin their long flights southward in the fall and back again in the spring. Temperature and precipitation also influence the timing and availability of flowers, seeds, and other food sources for the birds when they reach their destinations (Pianin, 2002, A-3).
Peter Schultz, a global warming expert with The National Research Council, a nonprofit organization, cautioned that long-term forecasts of disruptions in bird migration patterns are difficult. "I would be surprised if the distribution of state birds is not changed down the road," he said, "But predicting precisely where they'll be 50 years from now is very difficult, if not impossible, with the current state of knowledge" (Pianin, 2002, A-3).
Baltimore orioles (Icterus galbula) were once so numerous that the naturalist painter John J. Audubon wrote about the delight of hearing "the melody resulting from thousands of musical voices that come from some neighboring tree" (Pianin, 2002, A-3). The bird, a Maryland icon whose name was adopted by Baltimore's major-league baseball team, was officially designated the state bird in 1947. Local legend maintains that George Calvert, the first baron of Baltimore, liked the oriole's bright-orange plumage so much that he adopted its colors for his coat of arms.
Global warming is not the only danger to the oriole and other well-known birds. Its decline results also from diminishing breeding habitat and forests in North America (where orioles spend summers) and in Central and South America, where they fly for the winter. "Climate change on top of fragmented habitat is the straw that breaks the camel's back," said Patricia Glick, an expert on climate change with the National
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