Sökning: "Passerines"
Visar resultat 1 - 5 av 19 avhandlingar innehållade ordet Passerines.
1. Flight Behaviour of Passerines on Nocturnal Migration
Sammanfattning : Many passerines migrate during the night and at high altitudes, making their migration difficult to observe. By using tracking radars we have been able to make exact observations of the flight behaviour of passerines on nocturnal migration, which has enabled us to test several hypotheses about adaptive values and constraints regarding migratory behaviour in different ecological contexts. LÄS MER
2. Metals take flight : Transport and effects across ecosystems
Sammanfattning : Metal contamination can have severe toxic effects in the ecosystems, resulting in loss of biodiversity, reduced abundance of organisms, and loss of ecosystem services. Traditionally, aquatic ecosystems have been regarded as a sink of metal contamination. LÄS MER
3. Fattening strategies in wintering passerines
Sammanfattning : Stored fat is a main source of energy for birds in winter and it seems reasonable that fatter birds should survive better. Small birds wintering at high latitudes, however, carry less fat than their capacity permits, suggesting a predation cost of excessive fatness. LÄS MER
4. Stopover behaviour in migratory songbirds: timing, orientation and departures
Sammanfattning : Songbird migrants use stopovers between flight bouts to rest and refuel for the upcoming flights. Behaviours affecting where, when and how long to stay at stopover sites will affect how successful the overall migration will be, which has significant consequences for the overall fitness and mortality of the birds. LÄS MER
5. Effects of created habitats on farmland biodiversity
Sammanfattning : Agricultural intensification has caused severe declines among biodiversity in European farmland over the last half century. The transformation of the agricultural landscape has led to reduced availability of key resources such as food, nesting habitat and shelter. LÄS MER