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	Tern Restoration in 2002

Another Year of Growth: Tern Restoration at the Isles of Shoals

by Diane De Luca  Senior Biologist/Ornithologist

A well-placed roving blind looks out over the rock jumble along the western side of Seavey Island. The blind placement allows for some spectacular views of a group of more than ten Roseate Tern nests. This is only one of a number of rocky locations that host a group of roseates this 2002 field season. Last year, we rejoiced in the success of our first Roseate Tern nest. This year, our numbers climbed to 25 confirmed breeding roseate pairs. Along with the very significant growth in the Seavey Island roseate population, the summer of 2002 also saw a phenomenal increase in Common Tern numbers to 1687 pairs and the first breeding of an Arctic Tern pair in more than 50 years. This rocky island that was without any terns for so many years is now home to one of the largest tern colonies in the Gulf of Maine. Even those of us who have been an intimate part of the project are overwhelmed by the rapid growth and success at this site. History In 1997, the Audubon Society of New Hampshire, in partnership with the New Hampshire Fish and Game Department Nongame Program and with support from the Office of State Planning Coastal Program, the Department of Resources and Economic Development Parks Division, USDA Animal Damage Control, Shoals Marine Laboratory, Isles of Shoals Steamship Company, Gulf of Maine Seabird Working Group, and the U.S. Fish and Wildlife Service, worked cooperatively to successfully complete the first year of this project by using nonlethal means of gull control along with decoys and tern colony sounds to attract breeding terns back to the Isles of Shoals. A small colony of six pairs of Common Terns raised and fledged six young at this site. This was the first documented breeding by terns at the Isles of Shoals since the early 1950s. The 1998 through 2001 field seasons saw significant growth as the number of breeding Common Terns climbed to 45, 141, 446, and 809 pairs, respectively. 2002 Tern Numbers The numbers for the 2002 field season speak volumes for this colony. Census Species Common Terns Roseate Terns Arctic Terns Date 6/20/2002 6/20/2002 6/20/2002 A Wave 1273 8 1 Date 7/15/02 7/15/02 7/15/02 B Wave 414 17 - Total Nests 1687 25 1 Population Information (Totals) Species/Yr. 1998 (pairs) 1999 2000 2001 2002 Common 45 141 446 809 1687 Roseate 0 0 0 1 25 Arctic 0 0 0 0 1 A rough storm on June 15-16 created 16-foot seas but did not appear to impact the colony, because it occurred just before hatch. There were no other significant weather-related problems. Predation was not observed up through July 8. However, a practicing chick was taken by a gull on July 8, and during the period from July 20-27 approximately thirty-five chicks were taken, including one confirmed Arctic Tern chick. Gull predation, in spite of vigorous efforts by the tern biologists, had the most significant impact on tern productivity. Even with the predation, this was another excellent year for the Seavey Island tern colony. This New Hampshire colony had one of the highest productivity rates of any Common Tern colony in the entire Gulf of Maine (Nova Scotia to Massachusetts). This is an amazing and constantly hopeful statistic for terns in our state. The continued struggles of the 2002 New Hampshire mainland colonies (where only a handful of chicks fledged) also puts the strength of the Seavey Island colony into perspective. Feeding Study The study of tern feeding has taken place on managed islands in Maine and Massachusetts for a number of years. Our tern feeding study is modeled after this work and contributes to a growing database. The years of feeding data have yielded some very interesting results in terms of abundance and cycling of food sources, as well as the correlation of chick survival with food availability. The goals of the feeding study were to determine the identification of food items being provided to the chicks, the feeding rate, receiving chicks, and nest productivity. With the exception of 2001, hake has always constituted the largest part of the diet on Seavey Island. This continued in 2002. Mackerel continued to climb in the last part of July and early August. Another important finding was that the feeding rate continues to show that the adult terns are feeding in very close proximity to White and Seavey Islands. This is a very positive confirmation for this growing colony, as the food resources needed to successfully raise chicks were available in 1998-2002. Banding From 1998-2002, we have worked to maximize the number of chicks banded with special salt-resistant metal bands to facilitate data on colony growth and nest site fidelity. Close to 300 chicks were banded in 2002. Tern chicks do not typically return to the breeding colony until they are two or three years of age and may not breed until they are four years of age. We have identified many Seavey Island chicks that have returned to the island from the 1998-2000 cohorts. A number of these birds were also confirmed as breeders… a great sign for future recruitment. We are hopeful that the large number of chicks banded will provide additional survival and movement data in the coming years. We have also been able to read the bands on more than 100 adult terns that are now part of the Seavey Island colony. This data give us a picture of where our growing colony is originating. Band information tells us that we have breeding birds that were hatched on islands as far away as Great Gull Island, Long Island, New York, and numerous individuals from Jenny and Stratton Islands off the coast of Maine. Educational Outreach The Tern Restoration Project has provided an excellent opportunity for educational outreach. The focus of this outreach has been to foster stewardship, appreciation, and protection for nesting seabird colonies at White and Seavey as well as other Gulf of Maine seabird nesting islands. Opportunities have come through welcoming visitors and organized classes to the island, sharing the details of the project with charter and ferry boats that visit the Isles of Shoals, and taking the project out to many groups around New Hampshire through a slide presentation and display. The Future The nesting success and growth of the tern colony on Seavey Island is a good sign for continued population growth in the coming years. It remains important that intensive management continues at this site in the near future. Other tern recolonization projects have shown that productivity at these colonies is directly correlated to the level of management aimed at eliminating or ameliorating factors that currently limit successful tern nesting. Thanks My deepest appreciation goes to the 2002 tern biologists, Dan Hayward, Kristen Bixler, and Susan Elliott, for their hard work and tenacity. Special thanks also go to all of the other individuals who helped staff the island through the field season. Additional thanks go to the many people who have supported the project logistically, including the Shoals Marine Lab, Jon Savage of Cap'N Sav's Charters, and Sue Reynolds of Island Cruises. Thanks also go to the many other volunteers and supporters, without whom the project would not be possible.