European Shag (Phalacrocorax aristotelis) Science Article 2 abstract In temperate regions, winter presents animals with a number of challenges including depressed food abundance, increased daily energy requirements, higher frequency of extreme weather events and shortened day length. Overcoming these constraints is critical for overwintering survival and scheduling of future breeding of long-lived species and is […]

European Shag (Phalacrocorax aristotelis) Science Article 3 abstract This study analyses the mortality of chicks of the European Shag Stictocarbo aristotelis in the Cies Islands (NW Spain). Chick mortality on this island is the main cause of the yearly variation in chick production. By visiting the nests after hatching occurred we determined the periods of […]

European Shag (Phalacrocorax aristotelis) Science Article 1 abstract The European Shag Stictocarbo aristotelis is dimorphic in body size : males are 22% heavier than females . We used molecular techniques to sex of 25 male and 18 female chicks in colonies from the Cies Islands (NW Spain). Discriminant functions were then obtained based on morphometric […]

European Shag (Phalacrocorax aristotelis) Science Article 5 abstract We compared morphometrics and discriminant functions for sexing European Shags Phalacrocorax aristotelis in a central (British) population and a peripheral (NW Iberia) population within its distribution range, to account for structural differences between populations and sexes. Overall, British shags were structurally larger than Iberian shags, except in […]

European Shag (Phalacrocorax aristotelis) Science Article 4 abstract While age related improvements in breeding success have been reported in many avian species, the underlying mechanisms are not well understood. Ectoparasite load can have a significant deleterious effect on many aspects of host fitness. If younger breeders carry high parasite loads, and this has a detrimental […]

Double-crested Cormorant (Phalacrocorax auritus) Science Article 10 abstract The breeding colony of the Double-crested Cormorant (Phalacrocorax auritus) on East Sand Island in the Columbia River estuary has grown dramatically over the last 13 years, in contrast to declines at other colonies along the coast of the Pacific Northwest. Immigration from other colonies has occurred and […]

Double-crested Cormorant (Phalacrocorax auritus) Science Article 18 abstract The objectives for this study were to: 1) determine the diet of Double-crested Cormorants (Phalacrocorax auritus, hereafter: cormorants) in western Lake Erie; 2) to determine if yellow perch (Perca flavescens) or walleye (Sander vitreus) were a noteworthy prey item; and 3) to determine if the invasive round […]

Double-crested Cormorant (Phalacrocorax auritus) Science Article 17 abstract The nesting colony of Double-crested Cormorants, Phalacrocorax auritus (Lesson, 1831), on East Sand Island in the Columbia River estuary is currently the largest for this species on the Pacific Coast of North America. We used radiotelemetry to investigate the spatial and temporal foraging patterns of nesting cormorants […]

Double-crested Cormorant (Phalacrocorax auritus) Science Article 15 abstract The ability to determine the age of birds accurately from their skeletons would be useful not only for population biology and wildlife management research but for avian palaeontological and archaeological analyses as well. While accurate osteologically based age determination techniques are available for some amphibians and reptiles […]

Double-crested Cormorant (Phalacrocorax auritus) Science Article 16 abstract Double-crested Cormorants (Phalacmcorax avril us) are normally considered a diurnal species. Herewe describe cormorants foraging nocturnally in an oxbow lake in Mississippi. We have observed this behavior onlyonce during 30 capture attempts over seven years. D. Tommy King, J. Brent Harrf, Brian Dorr and David Reinhoid, Colonial […]