Pochard (Aythya ferina) Science Article 1 abstract Intersexual differences in feeding rates, aggression rates, an d feeding site selection were investi gated in a flock of up to 2700 Pochard Aythya ferina wintering at Salford docks, Greater M anchester (239 males per 100 females) . As often found elsewhere, females were less aggressive than males, […]
Category: Anseriformes
Spring migration strategies in Pink-footed Geese Anser brachyrhynchus an d consequences for spring fattening and fecundity.
Pink-footed Goose (Anser brachyrhynchus) Science Article 1 abstract Individu al variation in spring migration strategies was analysed for neckbanded Pink-footed Geese Anser brachyrhynchus migrating from Denmark (D) via stopover sites in the Trondheimsfjord area (T) in mid-Norway and Vesteralen (V) in northern Norway to the breeding grounds in Svalbard, 1990-97 . Body condition of marked […]
Diet and habitat use of Svalbard Pink-footed Geese Anser brachyrhynchus during arrival and pre-breeding periods in Adventdalen.
Pink-footed Goose (Anser brachyrhynchus) Science Article 4 abstract The feeding behaviour of Pink-footed Geese Anser brachyrhynchus was studied in Adventdalen, Svalbard during 15-28 May 2004 to determine habitat use of newly arrived birds based on their distribution in relation to the major vegetation types present. Goose numbers increased from initial arrival on 15 May to […]
Pink-footed Goose Anser brachyrhynchus (Greenland/Iceland population) in Britain1960/61-1999/2000
Pink-footed Goose (Anser brachyrhynchus) Science Article 2 abstract This report examines changes in the abundance and non-breeding distribution of the Greenland/Iceland population of Pink-footed Goose Anser brachyrhynchus during the period 1960/61 to 1999/2000. It also aims to evaluate the historical status of this population, to review published information on the ecology, population dynamics and conservation […]
Intake rates, stochasticity, or onset of spring-what aspects of food availability affect spring migration patterns in Pink-footed Geese Anser brachyrhynchus?
Pink-footed Goose (Anser brachyrhynchus) Science Article 6 abstract Long-distance bird migration consists of several flight episodes interrupted by a series of resting and refuelling periods on stopover sites. We assessed the role of food availability as the determinant of staging decisions focusing on the following three aspects of food availability: intake rates, stochasticity in intake […]
Pre-nesting site use of satellite transmitter tagged Svalbard Pink-footed Geese Anser brachyrhynchus.
Pink-footed Goose (Anser brachyrhynchus) Science Article 5 abstract We deployed satellite transmitters (PTTs) to Pink-footed Geese Anser brachyrhynchus to discover pre-nesting sites on Svalbard. 14 adult male were caught in Vest Stadil Fjord, Denmark and fitted with PTTs powered by batteries (n = 11; 30 g) or by solar power (n = 3; 45 g), […]
Crop damage and management of the Pink-footed Goose Anser brachyrhynchus in Denmark
Pink-footed Goose (Anser brachyrhynchus) Science Article 3 abstract More than 25 000 Pink-footed Geese Anser brachyrhynchus migrate through and stage on sites on the West Coast of Jutland in Denmark every year in autumn and spring. There is currently concern at the rate of loss of suitable staging habitats, as well as problems of conflict […]
Activities of tabanids (Diptera, Tabanidae) attacking domestic duck-Cairina moschata (Linnaeus) (Aves, Anatidae), introduced in a forest area in the Central Amazon, Manaus, Brazil
Muscovy Duck (Cairina moschata) Science Article 1 abstract Presented here are the feeding habits, attack behavior, daily and annual activity of adult of Phorcotabanuscinereus (Wiedeman, 1821), Chrysops laetus (Fabricius, 1805) and Phaeotabanus cajennensis (Fabricius, 1787), whilebiting a domestic duck, Cairina moschata (Linnaeus, 1758). The last two species were recorded for the first timeattacking birds. This […]
Pair formation among experimentally introduced mallards Anas platyrhynchos reflects habitat quality
Mallard (Anas platyrhynchos) Science Article 1 abstract Using data from two independent field experiments, we address whether pair formation in introduced mallards Anas platyrhynchos is associated with habitat quality, specifically food limitation at the brood stage. Based on the concentration of total phosphorous in the water, the study lakes were divided into two groups, poor’ […]
Testosterone and testes size in mallards ( Anas platyrhynchos)
Mallard (Anas platyrhynchos) Science Article 6 abstract The steroid hormone testosterone (T) mediates the expression of many secondary sexual characters, including behaviors which in.uence male reproductive success. Testes are one of the major sources of androgens, in particular of T. Although a positive relationship between testes size and T levels could be hypothesized, it has […]