Tag: all of Larus

Astaxanthin is responsible for the pink plumage flushin Franklin’s and Ring-billed gulls

Ring-billed Gull (Larus delawarensis) Science Article 3 abstract Carotenoid pigments produce the red, orange, and yellow plumage of many birds. Carotenoidcontainingfeathers are typically rich in color and displayed by all adult members of the species. In many gulls andterns, however, an unusual light pink coloring (or flush) to the normally white plumage can be found […]

Impact of the Ring-Billed Gull (Larus delawarensis) on the Microbiological Quality of Recreational Water

Ring-billed Gull (Larus delawarensis) Science Article 1 abstract We evaluated the impact of the ring-billed gull (Larus delawarensis) on the microbiological quality of water. We measured fecal coliforms, Salmonella spp., and aeromonas spp. in the gull droppings and the number of fecal coliforms in the water prior to and after attracting these birds to the […]

METABOLISM AND THERMOREGULATION IN HATCHLING WESTERN GULLS

Ring-billed Gull (Larus delawarensis) Science Article 9 abstract Parental attentiveness provides hatchlings of many precocial and serniprecocial birds with a large measure of protection from the vagaries of the thermal environment. Nonetheless some of these species differ in thermoregulatory capacity of newly hatched chicks, in correlation with climatic conditions during the breeding season. WILLIAM R. […]

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 […]

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 […]

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, […]