Structure of the New England Herring Gull Population

Abstract

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Habitat Selection and Its Effect on Reproductive Output in the Herring Gull in Newfoundland

“…Working on related species, Hunt and Hunt (1976) have shown that heavier chicks have a higher survival rate, and Briggs (1977) has shown that early hatched gull chicks tend to be larger and socially dominant over smaller and later-hatched chicks at food sources during the winter. It is generally agreed that the first winter is crucial in determining survival of young gulls, because this is when they suffer their highest rate of mortality (Kadlec and Drury 1968, Spaans 1971, Coulter 1975, Briggs 1977. In fact, mortality during this period may be higher than during the 1st wk of life, which is considered to be the time when the highest mortality rate occurs in most species (compare Kadlec and Drury 1968: Table 22 with Hunt and Hunt 1976: Table 2).…”

“…It is generally agreed that the first winter is crucial in determining survival of young gulls, because this is when they suffer their highest rate of mortality (Kadlec and Drury 1968, Spaans 1971, Coulter 1975, Briggs 1977. In fact, mortality during this period may be higher than during the 1st wk of life, which is considered to be the time when the highest mortality rate occurs in most species (compare Kadlec and Drury 1968: Table 22 with Hunt and Hunt 1976: Table 2). Because growth rate was shown to be positively correlated with prefledging survival of chicks in this study, gulls nesting in rocky habitat may produce more offspring that survive the first winter, even though they may not fledge more chicks at the end of the breeding period.…”

“…As the number of chicks fledged per pair is essentially the same in these two habitats, survival until reproductive age of birds from rocky habitat would have to be more than double that of birds from puffin habitat for recruitment to be higher from rocky habitat. Very little recruitment probably comes from meadow habitat, because these birds are not even producing enough offspring to maintain a stable population (assuming that this requires 10% annual adult mortality, 50% survival from fledging to reproductive age, and four reproductive seasons; Kadlec and Drury 1968).…”

“…However, long-term banding studies of Herring Gulls have indicated that although many individuals return to their natal colony to breed, many others settle in completely different areas (Kadlec and Drury 1968, Spaans 1971. It is not known if there is a tendency, either innate or learned, for gulls to settle in the type of habitat in which they were raised.…”

Abundance of Gulls and Other Birds at Landfills in Northern Ohio

“…To make informed decisions on landfill sitings and operations with regard to aircraft safety, more information is needed on the extent and pattern of daily bird use (feeding, soaring, loafing) of landfills and the area around landfills (Lake, 1984;McLaren et al, 1984;Risley and Blokpoel, 1984;Southern and Southern, 1984;Forsythe and Austin, 1984). In addition, we know little about the contribution that abundant dependable food at landfills has made to the overall population increases of gulls in many areas of North America (Kadlec and Drury, 1968;Ludwig, 1974;Blokpoel and Tessier, 1986).…”