This species qualifies as Critically Endangered because the very rapid rate of decline is expected to increase owing to habitat loss and degradation. This is combined with the impact of introduced predators including brown tree snake on Saipan. It is a 18 cm large, scruffy-looking warbler with long bill and erect head feathers when singing. […]
This species occurs on one extremely small island and undergoes marked population fluctuations, owing to climatic events, reducing it to tiny numbers. It is a 13 cm small, inconspicuous, thin-billed warbler. Brown above, darkest on crown, white below. It sings a simple song of rapid, metallic notes. It is endemic to the steep, rocky island […]
Sykess Warbler (Iduna rama) Science Article 1 abstract In early-January 2000, one of us (GMK) received a communication from Michael Walters, the former Curator of Eggs at the Natural History Museum (Tring), concerning a recent short note by Castell (1999, see below) within these pages, in which a nest, apparently of Hippolais rama, was depicted. […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 10 abstract Mark-recapture ringing data from Wicken Fen in Cambridgeshire and Gosforth Park in Newcastle upon Tyne were used to estimate adult survival rates in a southerly and a northerly population of Reed Warblers in England. The computer program MARK was used to estimate survival and recapture rates, adjusted […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 9 abstract The foraging movements of European Reed Warblers Acrocephalus scirpaceus and Sedge Warblers Acrocephalus schoenobaenus at migratory stopover sites were studied by comparing the frequency distribution of distances between capture-recapture localities of individual birds with a simulation model of a random distribution of movements. The results indicate that […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 5 abstract The size of an animal is of utmost importance for its overall success and each species isthought to have its own optimal size. If this is true, size traits ought to be understabilising selection unless the animal is living in a highly unstable environment. Winglength is a […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 7 abstract Previous studies have shown that female sedge warblers choose to mate with males that have more complexsongs, and sexual selection has driven the evolution of both song complexity and the size of the majorsong control area (HVc) in the brain. In songbirds, learning from conspeci? cs plays […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 1 abstract Increases in fat and pectoral muscle mass are important physiological changes associated with migration, but the extent to which these are linked is uncertain. The relationship between fat and pectoral muscle in first-year Sedge Warblers Acrocephalus schoenob nus was investigated using the carcasses of 20 birds that […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 8 abstract Sedge Warbler populations in The Netherlands have declined dramatically over the last 25 years, especially between 1973-75 and 1982-85. Population declines correlate with yearly rainfall in the western part of the Sahel-Soudan zone, the most probable wintering area of West-European birds (after removing effects of autocorrelation, rs […]
Sedge Warbler (Acrocephalus schoenobaenus) Science Article 3 abstract Tape-luring often is used in studies of bird migration, and the technique can strongly augment the total number of birds captured. Additional captures from tape-luring could result from increasing the capture probability of birds already at the stopover site, or from attracting birds that normally would have […]