Vol. 1, No. 3
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Gulf of Maine Seabird Restoration Working Group management efforts boosting seabird populations on nesting islands Gulf-wide Coastal Management Fellow Stratton Island, Maine - After a day spent traversing the beach at a snail's pace, crouching over tern nests, counting hundreds of eggs, and receiving pecks to the head and a white washing in bird guano in return of their trouble, interns and volunteers anxiously await the results of the annual tern census as island steward Sean Donaghy jots a few numbers. "The number of roseate terns is up from 16 nesting pairs last year to 66 pairs this season," announces Donaghy, who works for National Audubon Society (NAS). This year's tally is welcome news, given that, ten years ago, only 52 pairs of endangered roseate terns nested in the entire Gulf of Maine. An annual tern census takes place on nearly 70 islands in the Gulf, about a dozen of which are managed by members of the Gulf of Maine Seabird Restoration Working Group known as GOMSWG. The group works to rebuild populations of terns. GOMSWG is also working to restore populations of Atlantic puffins, common murres, razorbill auks, piping plovers, and other species that have been depleted as a result of human activity. Their research also provides information on fishery productivity, evidence of toxic substances in the environment, and bird migration patterns. While the group's work originally focused solely on coastal Maine, GOMSWG has recently expanded its efforts to include Monomoy Island in Massachusetts; the Isles of Shoals off Portsmouth, New Hampshire; and Machias Seal Island south of Grand Manan Island, New Brunswick, where the US and Canada cooperate to manage bird habitat despite a sovereignty dispute. Hunting devastates seabirds Around the turn of the century, several seabird populations were nearly decimated by human exploitation and loss of nesting habitat. Seabird feathers were used to decorate hats, and their eggs, considered a delicacy, were stripped from nests on many islands, the more bountiful of which earned names such as Eastern and Western Egg Rock. Despite Congress' passage of the Migratory Bird Treaty Act in 1918, which permitted some recovery, tern numbers remain low, mostly due to an increase in populations of herring gulls and great black-backed gulls, which compete for prime nesting sites and prey on tern eggs and chicks. Naturalists attribute the gull population boom, up from 14 nesting colonies in 1901 to 242 colonies in 1996, to an increase in open landfills and the presence of fishing boats hauling their catch. Ralph Palmer, a Harvard University zoologist, estimates that in the 1930s as many as 8,000 pairs of common terns, 6,000 pairs of Arctic terns, and 275 pairs of roseate terns nested along coastal Maine. By the 1970s, populations had dwindled to about a fourth of their former numbers in most cases. The GOMSWG hopes to restore tern populations to the levels observed in the early 1900s. Because the group has only recently expanded its efforts Gulf-wide, it bases its goals on coastal Maine population histories for the time being. Dr. Stephen Kress, manager of the NAS Maine Coast Sanctuaries, has worked for more than 25 years to restore populations of seabird species native to the Gulf using decoys, sounds, and other attraction methods. "By the mid 1900s, nesting islands had dwindled to just a few," said Kress. A non-profit organization supported mostly by personal donations, NAS "was only able to manage Eastern Egg Rock and a few other small islands," he said. In 1984, in response to a 50 year decline in tern populations, Kress and representatives from state, federal, and private organizations formed GOMSWG. The working group's members include NAS, The Nature Conservancy, US Fish and Wildlife Service (USFWS), Maine Department of Inland Fisheries and Wildlife, Maine Audubon Society, Damariscotta River Association, University of New Brunswick, and the College of the Atlantic. "With so many individuals and organizations involved, we are able to address the issue on a much larger [geographical] scale, and therefore will be more likely to restore sustainable seabird populations," said Kress, noting, "Coordination in research efforts and sharing of restoration techniques across borders is imperative to meeting our goals." Methods sometimes debated The working group says its management efforts are producing results. After a 44-year absence from Eastern Egg Rock, 54 pairs of terns nested there in 1980 thanks to GOMSWG's use of decoys, sound, gull control, and the posting of resident island stewards. Today, the island serves as a nesting site for 1,441 pairs of common terns, and 138 pairs of roseate terns - the largest common and roseate tern colonies in Maine. Stan Skutek, of Petit Manan National Wildlife Refuge, said results on Ship Island are equally exciting. "We have counted about 478 nesting pairs of common terns this season. Last season there were only 41," he explained. According to Donaghy, 821 pairs of common terns nested on Stratton Island this season, while none were counted here in 1985. The restoration of terns in coastal Maine has brought their numbers close the working group's goal. GOMSWG counted 7,102 pairs of common terns, 3,976 pairs of arctic terns, and 237 pairs of roseate terns this season. But Kress tempered his enthusiasm about the apparent resurgence, noting that many chicks died in the 1996 season's cold and damp conditions, and in 1983 an outbreak of Avian cholera significantly set back tern restoration progress on Eastern Egg Rock. While disease and storms are not human-induced problems, the working group maintains that, had humans not decimated the bird populations years ago, their numbers would be strong enough to allow them to recover from these sorts of natural setbacks. "A major benefit of the working group is that it promotes the spreading out of efforts to more islands," minimizing the detrimental effects of site-specific disasters, such as weather and disease, Skutek explained. Some of the group's methods, such as gull population control, are controversial, however. Gull nests have been baited with poison at several islands as a first step to restore terns but GOMSWG said it has not found it necessary to continue using that method. During subsequent seasons, island stewards shot individual gulls only if necessary to maintain nesting areas for terns, according to Kress. Kara Homquist, of the Massachusetts Society for the Prevention of Cruelty to Animals, said her group does not support any lethal means for controlling gulls, and called for more research before adopting such measures. "There is no real proof that gull numbers have to be reduced," she asserted, but according to Kress, "Saying no to controlling gulls is making a conscious decision to lose the terns." "Gulls, as much as any of the other bird species, are important for the ecological integrity of the Gulf of Maine," acknowledged Donaghy, noting that they are permitted to nest on other parts of Stratton Island and on neighboring Bluff Island. Nevertheless, he said GOMSWG uses gull population control as "a last resort measure" to ensure nesting habitat for other seabird species. Recently, US Department of Interior Secretary Bruce Babbitt halted the practice on Monomoy Island pending further evaluation. Long-distance travelers Terns arrive in the Gulf of Maine in early May to nest after wintering in the Southern Hemisphere, and Arctic terns annually travel 20,000 miles (32,186 kilometers) round-trip between the Arctic and Antarctica - a long-distance record for migratory birds. "The neatest part of observing the [terns] is spotting ones that you tagged a year or so ago, some of which were seen during the winter months in South America and have returned to nest," said Donaghy. Common and Arctic terns nest on gravely beaches between the high tide line and the upland vegetation, sometimes lining their nest with sticks and grasses, or simply scratching a depression in the sand between the cobbles. Roseate terns often hide their eggs among vegetation or near a piece of drift wood. Speckled, sand-colored chicks and eggs blend in with their surroundings, which offer some protection from gulls, owls, and other predators. Even so, while one parent leaves the nest to fish, the other stays behind to defend it in an aggressive manner that makes taking part in a tern census comparable auditioning for Hitchcock's The Birds. "The terns tend to attack the highest point of the invader," said Donaghy. In the field, experienced census takers wear tall, pointy birthday hats to deflect sharp beaks from the wearer's head, he explained. But the festive headgear offers minimal protection from the droppings with which terns bombard perceived invaders. Given the terns' apparent resurgence, however, a party atmosphere may be warranted even if the costumes don't meet every practical need. For more information on National Audubon Society's Seabird Restoration Program, write to Project Puffin, 159 Sapsucker Woods Road, Ithaca, New York, 14850. |
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Gulf of Maine Council on the Marine