— 2007 Season —
| Brief Summaries of Restoration Activities on Managed Islands: |
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Arctic, common, and roseate tern populations were decimated in the Gulf of Maine in the late 1800s due to a combination of shooting and egging for use as food and bait. Thousands of terns were also harvested to provide feathers for the growing millinery trade. When these activities were halted in the early 1900s, tern populations increased to at least 14,775 pairs in 1931 (including Machias Seal Island).
Unfortunately for the terns, gulls also benefited from federal protection, and their numbers increased rapidly along the coast. The prevalence of open landfills allowed herring and great black-backed gulls to produce a greater number of chicks. These chicks also experienced greater survival rates due to the year-round abundance of food. Both species are effective predators of tern eggs and young, and their presence can lead to complete nesting failure or island abandonment by many species of seabirds.
Gulls also initiate nesting earlier in the season than terns, which forces terns to nest in marginal habitat. As a result, terns may be more vulnerable to increased predation, inclement weather, and tides. We estimate that the Gulf of Maine gull population was 10,000 pairs in the early 1900s. By the late 1970s this number had increased to 100,000 pairs. The combination of expanding gull populations and habitat loss along the coast resulted in a continued population decline in terns for nearly 50 years.
We estimate the Gulf of Maine tern population was 5,320 pairs in 1977. Since 1977, an implemented management plan developed by the Gulf of Maine Seabird Working Group (GOMSWG) has worked to reverse this decline. Members of GOMSWG include Maine Department of Inland Fisheries and Wildlife (MDIFW), College of the Atlantic, National Audubon Society, Maine Audubon Society, Canadian Wildlife Service, and the U.S. Fish and Wildlife Service (Service).
The first task in re-establishing a colony was to make it safe for terns to nest on their former breeding islands. In some cases, it was sufficient to maintain a human presence on the island to discourage nesting gulls. In other cases, small populations of gulls have been controlled through egg and nest destruction, pyrotechnics, and limited shooting. Larger gull populations were removed with avicide DRC 1339. Avicide allowed managers to remove the breeding population of gulls in a relatively short period of time.
Continued gull harassment and nest destruction prevents any additional gulls from settling on the island. If the terns had recently abandoned the site, they may rapidly return to the island once the gulls are removed. However, some islands had not supported nesting terns in decades. In these situations it was necessary to actively attract the birds to the site using social attraction equipment. Managers erected sound systems to continuously play the sounds of a tern colony. Tern decoys were scattered throughout the area. Social attraction has been shown to be highly effective in re-establishing seabird colonies on several islands within the Gulf of Maine. Laughing gull, common eider, Leach’s storm-petrel, Atlantic puffin, razorbill, and black guillemot also colonized the islands once the gulls were removed.
In 2007, Maine supported 7,694 pairs of common terns nesting on 19 islands, 4,087 pairs of Arctic terns nesting on eight islands, and 227 pairs of roseate terns nesting on five islands in Maine. Although management on the nine restoration islands has resulted in significant progress toward our population goals, all three species remain 20 percent to 25 percent below 2006 MDIFW population objectives. Machias Seal Island, on the Maine — New Brunswick border, has recently supported over 3,200 pairs of terns. In 2006, predatory gulls consumed more than 1,700 tern nests before the entire Machais Seal Island tern colony abandoned. The island did not support any nesting terns in 2007.
Alcids have also responded favorably to our management efforts, and in 2006 we documented 790 pairs of Atlantic puffin on four islands and 482 pairs of razorbills on six islands. We did not conduct puffin and razorbill surveys on all the islands this season. While seabirds in Maine have generally experienced population growth in recent years, members of GOMSWG have identified the need to increase the number of seabird colonies along the Maine coast. Increasing the geographic distribution and the number of managed colonies would minimize the potential for a single catastrophic event (i.e., oil spill or disease) from devastating a significant percentage of the population.
Despite significant progress in our recovery efforts for both terns and alcids, we remain concerned that 95 percent of the terns in Maine nest on nine managed islands. Eastern Egg Rock supports 52 percent of Maine’s federally endangered roseate tern population. Arctic tern nesting distribution is limited to eight islands, with 90 percent of the terns breeding on three islands. Maine is the only state to support breeding populations of Atlantic puffins and razorbills. Three refuge islands support 88 percent of the puffins breeding in Maine. Razorbills currently nest on six islands, with 60 percent of the population nesting on Matinicus Rock.
2007 Survey Results |
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| Species | # Breeding Pairs | # Colonies |
| Roseate Tern | 227 | 5 |
| Arctic Tern | 4,087 | 8 |
| Common Tern | 7,694 | 19 |
| Atlantic Puffin | 800 | 4 |
| Razorbill | 500 | 6 |
| Laughing Gull | 4,066 | 3 |
Maine Coastal Islands National Wildlife Refuge:
- Within Maine 95 percent of Common and Arctic Terns, and all Roseate Terns, Laughing Gulls, and Atlantic Puffins nest on nine managed seabird islands.
- Maine Coastal Islands National Wildlife Refuge islands support 47 percent of the common terns and 95 percent of the Arctic Terns nesting in Maine. In the lower 48 contiguous states, Maine is the only state to support breeding Arctic terns. Refuge islands support 50 percent of the common terns and 94 percent of the Arctic terns nesting in Maine. The Arctic terns nesting on the refuge represent all the Arctic terns nesting in the lower 48 states.
- Within the United States, 88 percent of the Atlantic puffins nest on three islands within Maine Coastal Islands National Wildlife Refuge.
- Within Maine, 87 percent of the endangered roseate terns nest on two islands.
Comparison of Common Tern Populations on
Managed vs. Unmanaged Islands in Maine: 1984 – 2007
Comparison of Arctic Tern Populations on
Managed vs. Unmanaged Islands in Maine: 1984 – 2007
Pairs of Laughing Gulls Breeding on Eastern Egg Rock,
Matinicus Rock, and Petit Manan Island: 1991 – 2007
