The action of intra- and interspecific competition, mediated by density-dependent effects on growth, was investigated among the 3 helminth species found in the alimentary tract of 104 cormorants, Phalacrocorax carbo sinensis. Intraspecific density-dependent effects on worm sizes were observed in the abundant nematode Contracaecum rudolphii, as shown by a negative correlation between mean worm s...

OBJECTIVES Faecal Escherichia coli strains were isolated from great cormorants (Phalacrocorax carbo) and mallards (Anas platyrhynchos), which are commonly occurring waterbirds in Europe, and studied for resistance to cephalosporins and fluoroquinolones. METHODS Cloacal swabs or faeces from great cormorants and mallards in Central Europe were cultivated to isolate Escherichia coli strains with...

The larval development of the nematode Contracaecum rudolphii (Rudolphi, 1819), a common parasite of the proventriculus of cormorants, was experimentally studied. Within the eggs cultivated in freshwater under laboratory temperatures of 20-22 degrees C, the developing larva undergoes two moults on days 4-5, attaining the third larval stage. Most of the ensheathed third-stage larvae, 291-457 mic...

Nutrient enrichment in coastal marine systems can have profound impacts on trophic networks. In the Baltic Sea, the population of Great Cormorant (Phalacrocorax carbo sinensis) has increased nearly exponentially since the mid-1990 s, and colonies of these seabirds can be important sources of nitrogen enrichment for nearby benthic communities due to guano runoff. In this study we used stable iso...

Our previous study demonstrated that avian species possesses two distinct aryl hydrocarbon receptors (AHR1 and AHR2). To elucidate the functional characterization of avian AHRs, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) binding affinities and in vitro DRC-induced transcriptional activities of AHR isoforms from chicken (Gallus gallus), black-footed albatross (Phoebastria nigripes), common cormo...

Buoyancy is a de-stabilizing force for diving cormorants that forage at shallow depths. Having to counter this force increases the cost of transport underwater. Cormorants are known to be less buoyant than most water birds but are still highly buoyant (rho= approximately 0.8 kg m(-3)) due to their adaptations for aerial flight. Nevertheless, cormorants are known to dive at a wide range of depth...

Bird ringing was mainly used o riginally to study bird migrati on . However, it was reali sed as early as 1928 that encounters ( recoveries) of dead ringed birds contain information on survival-mortality processes. Lack was the ~ first to investigate surv ival processes in bird populations based on ringed --~~_ individuals, with attention to age dependence in su rv ival. Starting from early his...