The Tufted Puffin (Lunda cirrhata) apparently has the most extensive breeding distribution of any North Pacific seabird, extending in the western North Pacific from Hokkaido to the north Chukotsk Peninsula on the Chukchi Sea, and in North America from Cape Lisburne on the Chukchi Sea, south to the Farallon Islands off central California (Udvardy 1963). Despite this wide breeding distribution, the reported nesting habitat is generally restricted to steep, rocky islands and continental headlands (see Dement’ev and Gladkov 1951, Kozlova 1957, Gabrielson and Lincoln 1959, Portenko 1973, Sealy 1973, and Sowls et al. 1978). Nests are typically excavated in steep slopes and/or on vegetated plateaus, well above normal tidal influence but occasionally within the spray or storm-wash zone. Nowhere has L. cirrhata or any other puffin species been reported to nest in a flat, estuarine habitat in substrate normally affected by tides during the breeding season. Portenko (1973: 137) refers to Tufted Puffins breeding on Alyumka Island in the Anadyr "estuary" (64°40'N, 177°37'E), but Alyumka Island is a rocky coastal island having immediate offshore waters between 3-18 m deep (A.A. Kistchinski, The Ringing Center, Moscow, and George Tyner, U.S. Defense Mapping Agency, pers. comm.).

During the summers of 1976, 1977, and 1978, we found 14-18 pairs of Tufted Puffins nesting on 4 narrow sand islands (5-7 ha each) along the northcentral Alaska Peninsula at Nelson Lagoon (56°00'N, 161°10'W). As of June 1979, 25 active burrows had been reported there (Margaret R. Petersen, pers. comm.). The islands lie approximately 1.3 km from the Bering Sea coast and are protected from the sea by a long, narrow (0.5 kin) sand peninsula. The main deepwater channel in the lagoon, 3-7 m deep and 100-300 m wide at mean low water (MLW), separates the islands from the peninsula. The islands, which are free of permafrost, have a uniformly low profile with the highest elevation 1-2 m above mean high water (MHW) (Fig. 1). Each island is circumscribed by a gently sloping (<5°), narrow (5-15 m) sand/gravel beach that graduates at MLW to intertidal mud- and sandflats. These are extensive on the south and southeast sides (several hundred m) and relatively narrow (10-20 m) on the north and northwest or channel sides. The banks of each island are moderate to near vertical in slope. Puffin burrows face the channel, are located at or near the vegetation/beach interface, and extend into the bank horizontally or slightly downward. Beach rye (Elymus arenarius mollis) grows over most of each island and is used as nesting cover by several hundred Glaucous-winged Gulls (Larus glaucescens) and lesser numbers of Common Eiders (Somateria mollissima v-nigra). Predation by gulls on puffin eggs or chicks was not observed, nor did we see gulls rob food from adult puffins returning to their burrows from foraging in the Bering Sea (cf. Nettleship 1972). Puffins were never observed feeding in the lagoon.