Western Marsh Harrier (Circus aeruginosus) Science Article 8 abstract This note reports a case of predation by an adult female Marsh Harrier Circus aeruginosus onthree nests of Yellow-legged Gulls Larus michahellis at the Ebro Delta. The predation wasobserved on 4 April 2002 on one of the dykes that separate the saltpan-heaters of La Trinitat(Punta de […]
Reproduction of the Marsh Harrier Circus aeruginosus in recent land reclamations in The Netherlands.
Western Marsh Harrier (Circus aeruginosus) Science Article 6 abstract We studied temporal variation in reproductive performance of Marsh Harriers Circus aeruginosus in two land reclamations in The Netherlands, i.e. South Flevoland and the Lauwersmeerpolder, embanked in 1968 and 1969 respectively. The number of breeding pairs in Flevoland rapidly increased to a maximum of 350 pairs […]
Main migratory direction of Marsh HarrierCircus aeruginosus: an analysis of recovery data ofspecimens ringed in Latvia from 1925 to 2004
Western Marsh Harrier (Circus aeruginosus) Science Article 1 abstract Th is paper describes the main migratory directions of the Latvian Marsh Harrier Circus aeruginosuspopulation and provides an overview of recovery data. Th e study was based on analysis of recoverydata of Marsh Harrier that were ringed in Latvia from 1925 to 2004 and subsequently recovered.In […]
New material supplies in the Marsh Harrier Circus aeruginosus sexual roles daily and seasonal activity patterns and rainfall influence
Western Marsh Harrier (Circus aeruginosus) Science Article 5 abstract Nest maintenance is an important part of parental care for the Marsh Harrier Circus aeruginosus throughout the entire breeding period. Nest material supply trips are mainly carried out by the female as the male only contributes during incubation and the early nestling period. The trips rate […]
Long-Winged Harrier Predation on Wattled Jacana Eggs
Wattled Jacana (Jacana jacana) Science Article 1 abstract Long-winged Harriers (Circus buffoni) prey on small birds, mammals, and reptiles (ffrench, A Guide to the Birds of Trinidad and Tobago, 1973:1131. Although they take eggs of various species of birds (Haverschmidt, The Birds of Surinam 1968:67), no records are available on the efficiencies and rates of […]
BREEDING BEHAVIOR AND FOOD HABITS OF THE WATTLED JACANA
Wattled Jacana (Jacana jacana) Science Article 2 abstract Little is known about the biology of the Wattled Jacana (Jacana jacana), whereas the Northern Jacana (Jacana qinosa), has been studied in detail (Jenni 1974, Jenni and Collier 1972, Jenni et al. 1974). The Wattled Jacana inhabits fresh-water marshes from Panama and Colombia south to Bolivia, Argentina […]
Why is the Water Rail Rallus aquaticus a very scarce breedernorth of 61 deg N?
Water Rail (Rallus aquaticus) Science Article 2 abstract Along a transect from just north of Uppsala (c. 60 deg ?N) to Lulea (c. 65 deg 30′ N), the eastern coast of Sweden, we searched for Water Rails Rallus aquaticus. Rails were found at four of twenty-four visited sites, the northernmost site at 61 deg 08′ […]
Breeding of the Water Rail Rallus aquaticus in Cladium mariscusvegetation
Water Rail (Rallus aquaticus) Science Article 1 abstract We have studied breeding habitats of the Water Rail Rallus aquaticus in Cladium mariscus (Galingale) vegetation at Botshol (Abcoude, 51 deg 52’N;5 deg 04’E) in The Netherlands and on Oland in Sweden. Water Rails were localised by day by provoking vocal responses with a cassette recorder, using […]
Provisioning behaviour in relation to food availability and nestling food demand in the Water Pipit Anthus spinoletta
Water Pipit (Anthus spinoletta) Science Article 3 abstract Insufficient food provisioning by parents can reduce growth rate of altricial nestlings, their size and weight at fledging, and also affect survival. Therefore at low food availability, parents should increase their food provisioning effort. In insectivorous Water Pipits Anthus spinoletta prey biomass differed up to 50 times […]
Territory quality and reproductive success: Can water pipits Anthus spinoletta assess the relationship reliably?
Water Pipit (Anthus spinoletta) Science Article 2 abstract Variation in avian reproductive success is often caused by differences among territories in food supply, safety from predators and microclimatic conditions at the nest. Yet, in some habitats these components of territory quality, and hence future reproductive success, are difficult to assess at the time of settlement. […]