Category: Anseriformes

Multi-annual spatial and numeric dynamics of the white-headed duck Oxyura leucocephala in southern Europe: seasonality, density dependence and climatic variability

White-headed Duck (Oxyura leucocephala) Science Article 3 abstract A statistical model is developed for the globally threatened white-headed duck during its regional expansion throughout Spain from 1980 to 2000; the model estimates the relative intrinsic, climatic and stochastic effects on population fluctuations and spatial expansion on several time-scales. Facing the current lack of knowledge on […]

The influence of social interactions on the foraging path of Bewick’s Swans Cygnus columbianus bewickii.

Whistling Swan (Cygnus columbianus) Science Article 3 abstract The efficiency in which high-density food patches are found is determined by the way foragers move between patches. In this study we explore the effect of social interactions on the foraging path, in particular the distance moved between patches. We studied Bewick’s Swans Cygnus columbianus bewickii that […]

The condition of Bewick’s Swans Cygnus columbianus bewickii in winter as assessed by their abdominal profiles.

Whistling Swan (Cygnus columbianus) Science Article 1 abstract An Abdominal Profile (AP) scale was developed to assess body condition of Bewick’s Swans in the field. Change in AP score for individual birds correlated significantly with change in their body mass; moreover AP was significantly correlated with condition indices that were designed to remove the potential […]

Food intake rates and habitat segregation of Tufted Duck Aythya fuligula and Scaup Aythya marila exploiting Zebra Mussels Dreissena polymorpha.

Tufted Duck (Aythya fuligula) Science Article 1 abstract The foraging skills of Tufted Duck Aythya fuligula and Scaup Aythya marila feeding on Zebra Mussels Dreissena polymorpha were studied in experiments under semi-natural diving conditions with relevance to the IJsselmeer/Markermeer area (large lakes in the centre of The Netherlands, former Zuiderzee area), the major freshwater wintering […]

Serological survey of viral pathogens in bean and white-fronted geese from Germany

Taiga Bean Goose (Anser fabalis fabalis) Science Article 1 abstract Sera from wild geese were tested for antibodies to selected viral pathogens at a resting site for wild waterfowl in Germany. Serum samples from both bean geese (Anser fabalis) and white-fronted geese (Anser albifrons) collected in October 1991 were examined using serological methods licensed for […]

Surf scoters Melanitta perspicillata aggregate in association with ephemerally abundant polychaetes

Surf Scoter (Melanitta perspicillata) Science Article 1 abstract […] During the week of 16-23 April 2003, we observed an unusually large aggregation of sea ducks and a Gray Whale Eschrichtius robustus foraging at Mapleguard Point, located in the southern portion of Baynes Sound, after which the site was abandoned. The flock consisted primarily of Surf […]

Habitat use by wintering Steller’s Eiders Polysticta stelleri in northern Norway.

Stellers Eider (Polysticta stelleri) Science Article 1 abstract Habitat use of Steller’s Eiders Polysticta stelleri was studied in Varangerfjord, northern Norway, during three winter periods (November, January and April) in 1996/97. We partitioned habitats based on water depth and benthic conditions, and compared the benthic characteristics in known feeding areas to nearby areas avoided by […]

Comparative energy budgets of Greater Snow Geese Chen caerulescens atlantica staging in two habitats in spring

Snow Goose (Anser caerulescens) Science Article 2 abstract During a recent population increase, the high-arctic nesting Greater Snow Goose Chen caerulescens atlantica greatly expanded its spring staging habitat. Over two decades, the flock over-spilled from its traditional fresh-water Scripus marshes of the upper St. Lawrence River estuary into the salt-water Spartina marshes of the lower […]