Tag: all of Larus

Importance of migrating salmon smolt in Ring-Billed (Larus delawarensis) and California Gull (L. californicus) diets near Priest Rapids Dam, Washington

Ring-billed Gull (Larus delawarensis) Science Article 2 abstract Ring-billed (Larus delawarensis) and California Gulls (L. californicus) have been implicated in depredations on migrating salmon smolt in the Columbia River. As part of a gull management program conducted in 1995 and 1996, we collected L. delawarensis (n = 120) and L. californicus (n = 45) near […]

MIGRATION AND DISPERSAL IN GREAT LAKES RING-BILLED AND HERRING GULLS

Ring-billed Gull (Larus delawarensis) Science Article 10 abstract Band-recovery dam for Ring-billed (Larus delawarensis) and Herring (L. argen- tatus) Gulls were analyzed to determine the origins of gulls breeding within the Great Lakes region, the extent of lake and colony fidelity, and the winter and breeding season distributions of gulls of various age classes STEVEN […]

PURSUIT AND CAPTURE OF A RING-BILLED GULL BY BALD EAGLES

Ring-billed Gull (Larus delawarensis) Science Article 4 abstract Bald Eagles (Haliaeetus leucocephalus) are opportunistic hunters that employ a numberof techniques to capture a wide variety of prey (Bent 1937, Brown and Amadon 1968,Sherrod et al. 1976, McEwan and Hirth 1980). These eagles are known to occasionallypursue prey, including flying birds, in pairs or larger groups […]

Parental condition, brood sex ratio and differential young survival:an experimental study in gulls ( Larus fuscus)

Lesser Black-backed Gull (Larus fuscus) Science Article 2 abstract Empirical evidence is growing that the offspring sex ratio in birds can be biased in relation to the body condition of parents during breeding. The sex ratio bias may come about because (1) the actual production of the two sexes may be skewed and/or (2) there […]

The nominate Lesser Black-backed Gull Larus fuscus fuscus, a gull with a tern-like feeding biology, and its recent decrease in northern Norway.

Lesser Black-backed Gull (Larus fuscus) Science Article 3 abstract In northern Norway, Larus fuscus fuscus feeds mainly offshore on the wing on pelagic fish and fishery discards. It avoids competition with other large gulls for concentrated stationary food sources such as garbage dumps and fish-factories. It is also inferior to the Herring Gull L. argentatus […]

Effects of vegetation on nest microclimate and breeding performanceof lesser black-backed gulls ( Larus fuscus)

Lesser Black-backed Gull (Larus fuscus) Science Article 1 abstract For birds that breed in large colonies, the overall area occupied by the colony generally comprises several sub-areas that di.er in physical and social features such as vegetation and breeding density. Birds arriving at a breeding colony select their nesting sites through a hierarchical process of […]

Herring Gull Larus argentatus and Lesser Black-backed Gull L. fuscus feeding at fishing vessels in the breeding season: Competitive scavenging versus efficient flying

Lesser Black-backed Gull (Larus fuscus) Science Article 4 abstract The distribution and feeding range of Herring Gulls and Lesser Black-backed Gulls breeding on the Dutch Wadden Sea islands were assessed, using the results of ship-based surveys in the southern North Sea. The occurrence of both species in association with commercial fishing vessels is described in […]

Observations of the Great Black-backed Gull in Bulgaria

Great Black-backed Gull (Larus marinus) Science Article 1 abstract Until now 59 Great Black-backed Gulls have been recorded on the territory of Bulgaria, mainly during the seasonal migrations and in winter. They prefer the sea coast, seldom they visit the inland reservoirs. The first autumn migrants reach the Black Sea after September 6th. A new […]

Courtship feeding between Yellow-legged Gull Larus cachinnans and Herring Gull L. argentatus in the Western Mediterranean

European Herring Gull (Larus argentatus) Science Article 5 abstract Several species of large white-headed gulls, genus Larus, often hybridize freely where they occur sympatrically (Ingolfsson 1987, Pierotti 1987, Spear 1987, Pierotti & Annett 1993). In the Ebro Delta (Ebro Delta National Park, 40

Effects of changes in the availability of human refuse on breeding parameters in a Herring Gull Larus argentatus population in Brittany, France

European Herring Gull (Larus argentatus) Science Article 7 abstract Feeding behaviour and breeding parameters of Herring Gulls Larus argentatus were studied on Treberon, France, before (1983-88) and after (1989) a decrease of 80% in the amount of refuse dumped at a nearby tip. In 1989, fewer gulls visited the refuse tip than before the alteration, […]