Black-legged Kittiwake (Rissa tridactyla) Science Article 5 abstract Socially monogamous partners suffer conflicting interests concerning various aspects of reproduction such as parental care, copulation and fertilization. Female black-legged kittiwakes commonly eject their mates’ sperm immediately following copulations. Because sperm ejection reduces male sperm competitiveness and paternity assurance, males and females have conflicting interests as regards […]
Category: Charadriiformes
The effectiveness of nest defense by Black-Tailed Godwits
Black-tailed Godwit (Limosa limosa) Science Article 2 abstract This paper describes measurements of the frequency of aerial attacks on avian predators by nesting Black-tailed Godwits. The effects of these attacks on the ranging behaviour of Carrion Crows and the removal of eggs from artificial nests are assessed and compared with the effects of similar attack […]
Body dimensions and mass of breeding and hatched Black-tailed Godwits(Limosa 1. limosa): a comparison between a West Siberian and a Dutchpopulation
Black-tailed Godwit (Limosa limosa) Science Article 1 abstract The breeding biology and habitat preference of the Black-tailed Godwit (Limosa l. limosa)was studied in the West Siberian forest-steppe in May and June 1995. The godwits preferreed and sedge marsh and edges of ponds and depressions. They breed in small aggrega-tions together with other waders such as […]
Hatching date influences age at first reproductionin the black-headed gull
Black-headed Gull (Larus ridibundus) Science Article 1 abstract In long-lived colonial birds, age at recruitment is an important life-history character. Variation in this parameter may reflect differences in several factors, including competitive ability and breeding strategies. Further, these differences may be due to timing of hatching (for instance through differences in competitive ability). We investigated […]
An experimental study on the causes of sex-biased mortality in the black-headed gull – the possible role of testosterone
Black-headed Gull (Larus ridibundus) Science Article 2 abstract During early development male offspring in avian species often suffer from enhanced mortality compared to female offspring. This has been attributed to different nutritional requirements, as sex-biased mortality has been reported particularly in sexually size-dimorphic species. However, other traits of the male phenotype, such as the embryonic […]
Field metabolic rates of Kittiwakes Rissa tridactyla during incubation and chick rearing.
Black-legged Kittiwake (Rissa tridactyla) Science Article 7 abstract We used doubly labelled water to study the field metabolic rates of breeding Kittiwakes Rissa tridactyla during the incubation phase, and to compare these with the metabolic rates of Kittiwakes rearing chicks. During the incubation phase, birds with two eggs spent an average (
Long-term fitness consequences of early conditions in the kittiwake
Black-legged Kittiwake (Rissa tridactyla) Science Article 8 abstract The long-term fitness consequences of conditions during development are receiving growing attention: they are at the interface between ecological and evolutionary processes. We addressed the influence of the length of the rearing period and
Black Tern (Chlidonias niger surinamensis):A Technical Conservation Assessment
Black Tern (Chlidonias niger) Science Article 1 abstract The black tern (Chlidonias niger surinamensis) still occupies most of its former range. The continental population likely numbers in the low to mid hundreds of thousands and appears stable within the habitat that remains. However, given the severity of previous declines, conservation of the black tern still […]
Overwintering of Black Skimmers in California:: Site Fidelity and Inter-Site Movements
Black Skimmer (Rynchops niger) Science Article 3 abstract During the last two decades, Black Skimmers (Rynchops niger) have become increasingly common along the southern California coast.They are now found year-round in southwestern California (Collinse t al. in press) and in northwestern Baja California (Palacios and Alfaro 1992). Little detailed information has been published, however, about […]
AGE AND SEX DETERMINATION IN BLACK SKIMMER CHICKS
Black Skimmer (Rynchops niger) Science Article 4 abstract Post-natal development was studied in 40 southern California Black Skimmer (Rynchops niger) chicks in order to develop a reliable method of aging and sexing pre-flying young in this sexually dimorphic species. Ages of chicks were determined from hatching dates and were calculated also from wing chord measurements. […]