Willow Warbler (Phylloscopus trochilus) Science Article 3 abstract Sperm cells are highly diversified in birds and considerable research effort has focused on variation in sperm morphology between species. However, surprisingly little is known about intraspecific variation in sperm morphology in birds. We analyzed between- and within-male variation in total sperm length in two passerine species, […]
Category: Eurasia
Spring passage of Willow Warbler Phylloscopus trochilusacross the western Mediterranean:comparing islands with the mainland
Willow Warbler (Phylloscopus trochilus) Science Article 4 abstract Spring migration of Willow Warbler Phylloscopus trochilus over the western Mediterranean was studied using observations collected at a ringing station on the mainland of Spain (Aiguamolls de l’Emporda), and at an island station (Cabrera, one of the Balearics). During the years 1993-2001, birds were caught and measured […]
Niche partitioning of two Palearctic passerinemigrants with Afrotropical residents in theirWest African winter quarters
Willow Warbler (Phylloscopus trochilus) Science Article 2 abstract In bird migration systems, the question of coexistence and competition of migrants with residents in the nonbreeding season andtheir role in shaping the evolution of present avian communities is much debated. However, conclusions are often drawn ina speculative way. In the Palearctic-African bird migration system, many studies […]
Progress with the statistical analysis of primary molt
Willow Warbler (Phylloscopus trochilus) Science Article 1 abstract This paper considers two extensions to the statistical analysis of primary molt. The first extension relates to thedevelopment of statistical models that allow the simultaneous estimation of molt parameters for diverse groups of birds.Parameter estimation uses the method of maximum likelihood and the EM algorithm. The likelihood […]
Plumage temperatures of Dippers Cinclus cinclus on the roost and in the hand: implications for handling small passerines
White-throated Dipper (Cinclus cinclus) Science Article 1 abstract The outer breast plumage temperature of Dippers Cinclus cinclus roosting beneath river bridges was measured using an infra red thermometer over the environmental temperature range -0.8 to +10.9 deg C. Plumage temperature was close to, and directly related to, the temperature of the birds’ surroundings, but significantly […]
Biometric differences among the Dipper Cinclus cinclus populations ofSpain
White-throated Dipper (Cinclus cinclus) Science Article 4 abstract The length of the tarsus and wing, and the weight of the Dipper were measured in four mountain ranges inSpain (Cantabrian Mountains, western Pyrenees, the Central Mountains and Sierra Nevada). Francisco CAMPOS et al, ACTA ORNITHOLOGICA Vol. 40 (2005) No. 2 Download article download full text (pdf)
Variation of pecking rate with sward height in wild wigeon Anas penelope
Wigeon (Anas penelope) Science Article 2 abstract We examined how pecking rate changed with sward height in wintering European wigeon Anas penelope in a nature reserve of the French Atlantic coast. Pecking rates were recorded as the time taken to perform 10 or 50 pecks. We found a negative correlation between pecking rate and sward […]
Feeding behaviour of breeding Wigeon Anas penelope in relation to seasonal emergence and swarming behaviour of chironomids.
Wigeon (Anas penelope) Science Article 3 abstract Emergence of chironomids started in mid-April, and reached a peak at the end of April and in the beginning of May. Most ‘spring’ chironomids emerged around noon, whereas the majority of chironomids emerging later in the season, appeared at night. In general, there was a positive correlation between […]
Constraints of feeding on Salicornia ramosissimaby wigeonAnas penelope: an experimental approach
Wigeon (Anas penelope) Science Article 1 abstract The coastal marshes of the Charente-Maritime (western France) are a major wintering area for wigeon Anas penelope. In these marshes, wigeon feed mainly on grasses, while foraging on Salicornia (a .eshy, succulent halophyte) is uncommon. In order to understand the reason for this under-exploitation, an experimental study was […]
Re-mating in migratory Wigeon Anas penelope
Wigeon (Anas penelope) Science Article 4 abstract This note describes re-mating in migratory Wigeon Anas penelope in subsequent winters. Three pairs, out of five cases where both male and female partners returned to the study area, reformed in the following winter. Mitchell C., ARDEA 85 (2): 275-277. Download article download full text (pdf)