GreenPort Forum: Birds in Massachusetts
GreenPort Forum: Birds in Massachusetts
Ornithologist Christopher Leahy shares the word on birds in Massachusetts
by Mary Holbrow
Photo: A wild turkey preens and stretches his barred wings in Mount Auburn Cemetery near the grave of Harriett Lawrence Hemenway, co-founder of the Massachusetts Audubon Society. The big bird owes his comfortable existence in part to state legislation promoted by Mrs. Hemenway’s organization, which backed an 1897 measure that stopped the slaughter of wild birds for their ornamental feathers.
Ornithologist Christopher Leahy shared some good news, some bad news, and some local history about Massachusetts birds and birding in his GreenPort Forum talk at the Cambridgeport Baptist Church on Tuesday evening, October 18. Coordinating the event for GreenPort were Steve Morr-Wineman, Randy Stern, and Sally Watermulder. GreenPort is a Cambridgeport neighborhood group formed in 2006 to promote strategies for sustainable living.
Leahy (left) holds the Massachusetts Audubon Society’s Gerard A. Bertrand Chair of Natural History and Field Ornithology. A conservationist for more than thirty years, he served as Director of Mass Audubon’s Center for Biological Conservation.
In a fast-paced hour, Leahy discussed highlights of the organization's newly published report, “State of the Birds 2011.” http://www.massaudubon.org/StateoftheBirds/
(Note: Three data collections used for the report are described at the bottom of this page.)
Leahy began his talk with the local history -- an account of the beginning of the Massachusetts Audubon Society in the late nineteenth century. The organization was founded by Harriett Lawrence Hemenway and her cousin Minna Hall, who had grown up together in Brookline.
As young women they lived in Boston, where they became aware of the ongoing slaughter of birds for feathers to adorn ladies’ hats. Mrs. Hemenway and Ms. Hall organized society women to protest and boycott the use of the plumes.
The women gave tea parties and benefits to promote their cause, and they sought the support of powerful men in business and public life. The organization that grew out of this effort was the Massachusetts Audubon Society, incorporated in 1896. The following year the state legislature made it illegal to trade in wild bird feathers in Massachusetts.
Harriett Hemenway is buried here in Cambridge (photo, left), in Mount Auburn Cemetery. The 175-acre park-like expanse, founded in 1871, shelters a wide range of local and migratory birds and is a magnet for birdwatchers.
The movement she and her friends started soon spread nation-wide, according to a report by James N. Levitt, Director of Harvard’s Internet and Conservation Project at the Taubman Center for State and Local Government, Kennedy School of Government. http://www.innovations.harvard.edu/cache/documents/25/2548.pdf
Leahy’s good news was that a number of species that were once rare here, including the wild turkey, red-bellied woodpecker, Carolina wren, and northern cardinal (photo, left), have become relatively common. Also significantly increased are the eastern bluebird, pileated woodpecker, red-tailed hawk, and wood duck populations.
Some of the successes are due to a return of forest habitat, he said. Other successes, such as that of the peregrine falcon, come from adaptation to changed environments. The falcons find food and nesting sites in urban and suburban areas.
Still other gains are the result of human intervention. Bluebirds, ospreys, and wood ducks have been helped by the installation of nest sites, Leahy said. Breeding programs also play a part.
“Bald eagles were brought in from the midwest; they bred them at Quabbin Reservoir, and now they’re doing well. With a lot of money and sufficient effort you can bring back a species.”
Leahy described a project to aid piping plovers, listed as an endangered species. They nest in a narrow band just above the water line at the seashore. Because beach parking is at a premium, nesting plovers had to compete with automobiles for space.
“But the chicks are tiny -- they fall into the tire tracks,” Leahy said. “Mass Audubon worked to restrict vehicle access to certain beaches during the breeding season.”
“This is what concerns us the most,” he said.
Birds in this category included many we would expect to see in and around Cambridge: northern flicker, eastern phoebe, blue jay, song sparrow, common grackle, Baltimore oriole.
“The kestrel (photo, above, by Ron Dunnington via Creative Commons) is essentially going extinct in Massachusetts,” he continued. “Shrubland birds like the white-throated sparrow are in decline . . . Twenty percent of the world’s birds -- 2,000 species -- face extinction.”
Factors contributing to the declines:
Collisions with glass, power lines, and cars; confusing city lights; pesticides; predation by raccoons and foxes and by feral or free-range cats; loss of marsh habitat due to the spread of purple loosestrife and common reed (Phragmites); habitat fragmentation or loss because of development and human activities. (Note: for more about these factors, and categories of birds that are threatened by them, see below under DETAILS. Also in the section is a list of global warming issues that affect bird populations.)
In conclusion, Leahy noted that certain birds used to be hailed as beneficial because they ate weed seeds or caught insects. He cautioned against trying to evaluate birds in utilitarian terms.
“Some things are literally priceless,” he said. “People used to come up to the ornithologist Roger Tory Peterson and ask, ‘What good are birds really?’”
Peterson’s answer: “Well, what good is a newborn baby?”
DETAILS FROM CHRISTOPHER LEAHY'S TALK
Trends in bird populations:
Some birds that appear to be doing well on the whole
- forest birds (examples: barred owl, pileated woodpecker, yellow-throated vireo)
- urban and suburban birds (examples: peregrine falcon, Cooper's hawk, cardinal)
Birds that exhibit various trends include coastal birds, affected by rising sea levels
- great egret: somewhat increased after population was reduced by feather trade
- long-tailed duck (migratory): many wintering around Nantucket
- willet: reviving after being over-hunted
- sharp-tailed sparrow: salt marsh habitat threatened by rising sea level; also affected by mercury
- dunlin: vulnerable to disruptions along long-distance migratory routes
Birds that appear to be in decline
- grassland birds (example: meadowlark, kestrel, bobolink)
- shrubland birds (example: white-throated sparrow)
- freshwater marsh birds, losing habitat because of the filling-in of marshland (example: American bittern, sora, Virginia rail)
- birds that nest on or near the ground (example: eastern towhee)
- birds that catch insects in the air column (example: tree swallow)
- long-distance migrants (example: several warbler species; also whip-poor-wills, which face this challenge plus several others, because they nest on or near the ground, depend on flying insects for food, and live in places that are subject to development or other disturbance.)
Global warming issues that affect birds:
- the shifting schedules of flowers and insects on which birds depend, and the range shifts of the birds themselves
- flooding of coastal habitats and changing marine ecology
- drying out of tropical wintering habitat
- increase in super-hot wildfires
- migration of pathogens such as West Nile virus
Data collections on which “State of the Birds 2011" is based included:
1. The Massachusetts Audubon Society’s Breeding Bird Atlases 1 & 2. In this study the state map is divided into 9-square-mile blocks, and a count is made of species identified in each block during the breeding season. The study compares two sets of data, the first collected from 1974 to 1979 (BBA 1), and the second collected from 2007 to 2010 (BBA 2).
2. The North American Breeding Bird Survey (BBS), a joint program of the U.S. Geological Survey’s Patuxent Wildlife Research Center and the Canadian Wildlife Service. The BBS records and compares numbers of individual birds seen or heard at half-mile intervals along selected routes throughout North America since 1966.
3. The National Audubon Society’s Christmas Bird Count (CBC). This study estimates trends in the abundance of winter bird populations nationwide over more than 50 years. It tallies birds sighted by volunteers in designated areas between December 14 and January 5 each year.