— 2004 Season —
| Brief Summaries of Restoration Activities on Managed Islands: |
|
In the late 1800s, Arctic, Common, and Roseate Tern populations were decimated throughout the Gulf of Maine due to a combination of shooting and egging for food and bait, and feather collection for the millinery trade. When these activities were halted in the early 1900's, tern populations increased on the Maine coast, reaching peak numbers of at least 14,775 pairs in 1931 (including Machias Seal Island). However, expanding gull populations and habitat loss along the coast resulted in a significant population decline over the next 50 years. The prevalence of open landfills along the coast of Maine allowed Herring and Great Black-backed Gulls to produce a greater number of chicks. These chicks experienced greater survival rates due to the abundance of food during the winter months. Both species of gulls 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 initiate nesting earlier in the season than terns, forcing the terns to nest in marginal habitat. As a result, terns may be more vulnerable to increased predation, inclement weather, and tides. Researchers estimated that the Gulf of Maine supported 10,000 pairs of gulls at the turn of the century, however, by the late 1970's this number had increased to 100,000 pairs. By 1977, the combination of predation, competition for nest sites, and habitat loss reduced the Gulf of Maine tern population to only 5,321 pairs. 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 (COA), National Audubon Society (NAS), Maine Audubon Society, (MAS), Canadian Wildlife Service (CWS), and the U.S. Fish and Wildlife Service (USFWS).
Members of GOMSWG have utilized numerous techniques to re-establish terns to their former nesting islands. The first objective was to make former tern nesting islands safe for the birds once again. In some cases, maintaining a human presence on the island to discourage nesting gulls was sufficient to allow the terns to re-colonize the site. Small populations of gulls have been controlled through egg and nest destruction, pyrotechnics, and limited shooting. However, if the gull population had grown too large, GOMSWG members utilized avicide (DRC 1339), placed on bread cubes within the gull nests. This method allowed managers to remove the breeding population of gulls in a relatively short period of time. As soon as the population of breeding individuals is removed from the island, it is possible to keep the gulls from re-establishing the island as a nesting colony through continued harassment and nest destruction. If the terns had recently abandoned the island, they may return to the island rapidly 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. Sound systems were erected to continuously play the sounds of a tern colony, and tern decoys were scattered throughout the area. This method of re-establishing a tern colony has shown to be highly effective on several islands throughout the Gulf of Maine. Removal of the breeding gulls from the nesting islands has also allowed numerous other seabird species (e.g. laughing gull, eider, petrel, puffin, razorbill, and guillemot) to re-colonize the islands.
Between 1984 and 2004, the Maine population of Common Terns increased 118% (2,543 to 5,547 pairs); Arctic Terns increased 100% (1,720 to 3,445 pairs), and the Roseate Tern population increased 123% (76 to 170 pairs). Unfortunately, Roseate Terns in Maine have recently experienced a 41% decline compared to the number of birds recorded between 2000 -2002. An additional 3,323 pairs of Arctic and Common Terns nested on Machias Seal Island. Members of GOMSWG have also identified the need to maintain numerous 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.
Although significant progress has been made in restoring terns and other seabird species to their historic levels, our population objectives have yet to be reached. Roseate Terns remain listed as an Endangered Species by both the Federal government and the State of Maine. Atlantic Puffin, Razorbills, and Arctic Terns are currently listed as Threatened by the State of Maine. Leach’s Storm Petrels, Laughing Gulls, and Common Terns are currently listed as Special Concern Species in Maine. In addition, over 94% of Common and Arctic Terns, and all Roseate Terns, Laughing Gulls, and Atlantic Puffins nest on 11 managed seabird restoration islands (6 are part of Maine Coastal Islands NWR). Outside of Alaska, over 96% of the Arctic Terns nest on four MCINWR islands. Within the United States, 88% of Atlantic Puffins nest on three MCINWR islands. Roseate Terns remain a particular concern, as 69% of the 170 endangered Roseate Terns nesting in Maine, nest on Eastern Egg Rock. Maine represents the southern extreme of the breeding range for several species of seabirds (i.e. Atlantic Puffin, Razorbill, and Black Guillemot) and the northern extreme for others (i.e. Laughing Gull). Species such as Arctic Tern, Leach’s Storm Petrel and Common Eider breed as far south as in Massachusetts, but only in very low numbers.
2004 Survey Results |
||
| Species | # Breeding Pairs | # Colonies |
| Roseate Terns | 170 | 7 |
| Arctic Terns | 3,445 | 10 |
| Common Terns | 5,547 | 22 |
| Atlantic Puffin | (minimum) 606 | 4 |
| Razorbill | (estimate) 353 | 6 |
| Laughing Gull | 2,992 | 5 |
Maine Coastal Islands National Wildlife Refuge:
- Within Maine over 94% of Common and Arctic Terns, and all Roseate Terns, Laughing Gulls, and Atlantic Puffins nest on 11 managed seabird islands.
- Maine Coastal Islands NWR islands support 61% of the Common Terns and 96% 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% of the Atlantic Puffins nest on three islands within Maine Coastal Islands NWR
- Within Maine, 69% of the endangered Roseate Terns nest on Eastern Egg Rock
Comparison of Common Tern Populations on Managed vs Unmanaged Islands in Maine: 1984–2004
Comparison of Arctic Tern Populations on Managed vs Unmanaged Islands in Maine: 1984–2004
Pairs of Laughing Gulls Breeding on Eastern Egg Rock, Matinicus Rock, and Petit Manan Island: 1991–2004
In 2002–2004, the breeding population of Laughing Gulls nesting on Petit Manan and Eastern Egg Rock were controlled through nest destruction.