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	Tern Restoration in 2003

Seavey Island Soars: Common, Roseate, and Arctic Tern Numbers Climb Dramatically

by Diane De Luca  Senior Biologist/Ornithologist

"The softest colors of the summer sky were reflected on its back and pointed wings, while its breast glowed with the faint blush of some rare seashell. The graceful outlines, the spotless purity of its delicate plumage, and the long tapering tail feathers…."           -Arthur Cleveland Bent The exquisite beauty of the Roseate Tern is reflected in Bent's description from so long ago. Sitting on the rocks above a dense stretch of vegetation, I can see into some of the best Roseate Tern habitat on Seavey Island. Pairs of roseates grace the rocks with elegant courtship postures. Long tails project behind, heads and bills are stretched toward the sky. The sun glows off their plumage, and they seem to shine from their rocky perches. In only the third year of roseate nesting on Seavey Island, they are seemingly everywhere. Sixty-three pairs of roseates are grouped among a literal swarm of over 2400 pairs of Common Terns and a tenacious six pairs of Arctic Terns. The numbers are almost staggering in contrast to the six pairs of Common Terns that first settled here back in 1997. History In 1997, New Hampshire Audubon, 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 2002 field seasons saw significant growth as the number of breeding Common Terns climbed to 45, 141, 446, 809, and 1687 pairs, respectively. Roseate and arctic pairs have colonized Seavey Island in the last three years as well. 2003 Tern Numbers The numbers for the 2003 field season continue to speak volumes for this colony. Common Terns climbed from close to 1700 pairs in 2002 to over 2400 pairs, while roseates jumped from 26 to 63 pairs. Well over 3000 Common Tern chicks and 56 Roseate Tern chicks fledged from this site. The island was literally buzzing by early August, with over 8000 terns calling this rocky five acres home. Seavey Island is now one of the largest Common Tern colonies in the Gulf of Maine and an important and growing nesting site for the federally endangered Roseate Tern. The continued strong growth of both common and roseate terns sends a strong message that a suitable breeding location was needed in this part of the Gulf of Maine. Year by Year Comparison (Season Totals) Species/Year 1997 1998 1999 2000 2001 2002 2003 COTE 6 45 140 446 809 1687 2414 ROST 0 0 0 0 1 26 63 ARTE 0 0 0 0 0 1 6 Common Tern [Season Totals] Year 1998 1999 2000 2001 2002 2003 Nests Monitored 45 25[140] 43 73 184 163 Mean Clutch Size 2.33 2.84 2.60 2.44 2.52 1.96 Mean Hatch 2.02 2.48 2.33 2.18 2.09 1.61 Fledglings/Nest 1.6 2.24[1.71] 1.58 1.68 1.63 1.33 Total Fledglings 72 314[240] 502 773 2075 3212 The Future The nesting success and growth of the tern colony on Seavey Island remains a good sign for continued population growth and stability in the coming years. It remains important that intensive management continues at this site in the near future, especially in light of the endangered Roseate Tern recolonization. Other tern restoration projects have shown that productivity of these colonies is directly correlated to the level of management aimed at eliminating or ameliorating factors that currently limit successful tern nesting. We are so fortunate to have the opportunity to participate in this type of management along our New Hampshire coast.