Category: Suliformes

Diet of great cormorants Phalacrocorax carbosinensis wintering in Malause (South-West France)

Great Cormorant (Phalacrocorax carbo) Science Article 6 abstract The diet of cormorants roosting at Malause on the Garonne River (South-West France) was studied by analyzing pellets collected during the winter 2001- 2002.This roost held a mean of 550 cormorants between October 2001 and March 2002,making it one of the most important winter roosts in France. […]

Plumage and sexual maturation in the Great Frigatebird Fregata minor in the Galapagos Islands

Great Frigatebird (Fregata minor) Science Article 1 abstract The adaptive significance of distinctive immature plumages and protracted sexual and plumage maturation in birds remains controversial. This study aimed to establish the pattern of plumage maturation and the age at first breeding in the Great Frigatebird Fregata minor in the Galapagos Islands. We found that Great […]

Mass fishing by Cormorants Phalacrocorax carbo sinensis at lake Ijsselmeer, The Netherlands: A recent and successful adaptation to a turbid environment.

Great Cormorant (Phalacrocorax carbo) Science Article 20 abstract The habit of mass fishing by Cormorants at lake IJsselmeer, The Netherlands, is a recent phenomenon. During the first half of the 1970s the birds changed behaviour probably as a result of the deteriorating under water visibility in the take (3-4 m water depth). The behavioural switch […]

Individual migration strategies in Cormorants Phalacrocorax carbo passing through or wintering in western France.

Great Cormorant (Phalacrocorax carbo) Science Article 16 abstract The attendance of individually recognisable Cormorants has been studied at a roost site in western France together with the overall use of this roost. Only first and second year birds arrived at the roost before mid-October and almost only 1st-year birds did so after February. In the […]

Are Cormorants Phalacrocorax carbo wintering in Switzerland approaching carrying capacity? An analysis of increase patterns and habitat choice.

Great Cormorant (Phalacrocorax carbo) Science Article 17 abstract The increase rate of Cormorant numbers overwintering in Switzerland between 1970 and 1990 was the same as in the strongly growing breeding population. From 1930 to 1970, however, wintering Cormorants increased while the breeding population remained stable. The reasons are believed to be a better food supply […]

Time and energy constraints of fishing behaviour in breeding Cormorants Phalacrocorax carbo sinensis at lake Ijsselmeer, The Netherlands.

Great Cormorant (Phalacrocorax carbo) Science Article 18 abstract Two Cormorant colonies in The Netherlands (Naardermeer and Oostvaardersplassen), exploiting the same water bodies but situated at different distances from them, were compared with respect to daily variations in exact fishing sites and corresponding variations in time budget and fish consumption. Mean flying distances between colony and […]

Daily energy expenditure of Great Cormorants Phalacrocorax carbo sinensis wintering at Lake Chiemsee, Southern Germany.

Great Cormorant (Phalacrocorax carbo) Science Article 32 abstract In the winters of 1993/94 and 1994/95 the daily energy expenditure (DEE) of Great Cormorants Phalacrocorax carbo sinensis was measured using the doubly labelled water technique (DLW). This was the first time the method has been used on a Phalacrocoracid species. DLW trials were carried out on […]

Sexual dimorphism in the Cormorant Phalacrocorax carbo sinensis: Possible implications for differences in structural size.

Great Cormorant (Phalacrocorax carbo) Science Article 27 abstract A sample of Cormorants which accidentily had been drowned in fishermen’s gear was used to study differences in morphological characters and diet between males and females. Males were significantly larger than females in all body dimensions, whereas size of juveniles and adults were the same. Discriminant analyses […]

Cormorants Phalacrocorax carbo sinensis in shallow eutrophic freshwater lakes: Prey choice and fish consumption in the non-breeding period and effects of large-scale fish removal.

Great Cormorant (Phalacrocorax carbo) Science Article 22 abstract During the period October 1989-April 1992 a study on Cormorant feeding ecology was carried out in two shallow lakes in The Netherlands: lake Veluwemeer and lake Wolderwijd (3240 and 2600 ha respectively). Increasing numbers of Cormorants use these lakes for feeding in the non-breeding season; the maximum […]

Where two subspecies meet: Origin, habitat choice and niche segregation of Cormorant Phalacrocorax c. carbo and P. c. sinensis in the common wintering area France, in relation to breeding isolation in Europe.

Great Cormorant (Phalacrocorax carbo) Science Article 24 abstract The wintering population of Cormorants Phalacrocorax carbo in France reached 66000 birds in January 1992 against 14 000 in 1983. This increase largely concerned the inland areas (holding 55% of the population instead of 28% in 1983). The most important area is the Loire Valley. Analysis of […]