Tag: Circus cyaneus

Veranderungen in der Zusammensetzung der PCB- und DDT-Gemische in verschiedenen Lebensstadien der Wiesenweihe (Circus pygargus) und der Rohrweihe (Circus aeruginosus) in Nordrhein-Westfalen, Deutschland

Northern Harrier (Circus cyaneus) Science Article 2 abstract Egg and liver samples of Montagu’s and Marsh Harriers from the 1990’s were examined for their burden of DDT and PCB. The DDT burden in both species was distinctly higher in the eggs than in juveniles and adults, whereby the values for the adults were clearly higher […]

Food-niche differentiation in sympatric Hen Circus cyaneus and Montagu’s Harriers Circus pygargus

Northern Harrier (Circus cyaneus) Science Article 4 abstract Hen Harriers Circus cyaneus and Montagu’s Harriers Circus pygargus are medium-sized raptors that differ in size (Hen Harrier being slightly bigger than Montagu’s Harrier) and breeding system (Montagu’s Harriers are semi-colonial and Hen Harriers defend nesting-hunting territories). In contrast, the diets of the two species when in […]

Habitat use by Hen Harriers Circus cyaneus on Orkney: implications of land-use change for this declining population

Northern Harrier (Circus cyaneus) Science Article 3 abstract The use of habitats by hunting Hen Harriers Circus cyaneus just prior to the settlement period was investigated on Orkney, where numbers have declined by 70% over the last 20 years. Both males and females hunted over areas that were closer to subsequent breeding territories. Neither sex […]

Movements of British Hen Harriers Circus cyaneus outside the breeding season

Northern Harrier (Circus cyaneus) Science Article 1 abstract Hen Harrier chicks were wing-tagged in four regions in Scotland and in North Wales between 1990 and 1995, and resighted or recovered dead as fully grown birds during the non-breeding season (August to April) throughout Britain and Ireland, and on the Continent, until April 1997. Results were […]