Northern Lapwing (Vanellus vanellus) Science Article 13 abstract The responses of three species of lapwings (Charadriidae: Vanellus spp.) to various potential predators and physically similar non-predators were recorded in the field in Kenya and Venezuela to determine how responses varied with stimulus and context of encounter JEFFREY R. WALTERS, Wilson Bull., 102(l), 1990, pp. 49-70 […]
Aggression among female lapwings, Vanellus vanellus
Northern Lapwing (Vanellus vanellus) Science Article 9 abstract Social monogamy is the most common pair bond in birds and one hypothesis for itsprevalence is that already mated females (
Swallow censuses in Northwest Germany(1986, 1991 and 1996)
Northern House-Martin (Delichon urbicum) Science Article 1 abstract Starting in 1961, from 50-100 villages and settlements in the industrial area of Hannover-Braunschweig (centred on Peine) have been checked at 5-year intervals to count the nesting populationof House Martin Delichon urbica and Barn Swallow Hirundo rustica, the method beinga direct nest count. The hitherto stable Barn […]
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 […]
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 […]
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 […]
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 […]
Age at first breeding and fitness in goshawk Accipiter gentilis
Northern Goshawk (Accipiter gentilis) Science Article 5 abstract Age at first breeding has a large influence on fitness and hence is crucial to the evolution of life-history strategies. Goshawks Accipiter gentilis start breeding aged 1-4 years. Using 30 years of data and both lifetime reproductive success (LRS) and lind as a fitness estimate for 74 […]
Site-specific variation in partial brood loss in northern goshawks
Northern Goshawk (Accipiter gentilis) Science Article 1 abstract While many studies have shown that patterns of partial brood loss often differ with offspring sex, food availability or between years, the question of whether family-size adjustment varies between sites has achieved little attention. I investigated this in Finnish northern goshawks Accipiter gentilis, and found that partial […]
Home range size, habitat use, activity patterns and hunting behaviour of urban-breeding Northern Goshawks Accipiter gentilis
Northern Goshawk (Accipiter gentilis) Science Article 4 abstract The Northern Goshawk Accipiter gentilis typically prefers woodland habitat for nesting and hunting. In recent decades, however, the species has started colonising urban environments across Europe. Here I present the first study on the ranging behaviour of urban-breeding Goshawks. Each year from 1997 to 1999, I tracked […]