Sökning: "foraging strategies"

Visar resultat 6 - 10 av 22 avhandlingar innehållade orden foraging strategies.

1. 6. Individual variation in behaviour: personality and performance of brown trout in the wild

   Författare :Bart Adriaenssens; Göteborgs universitet; []
   Nyckelord :behavioural syndromes; personality; life-history; boldness; hatchery; survival; growth; foraging; anti-predator behaviour; learning; brown trout;

   Sammanfattning : Individuals from the same population often show very different behaviour. These differences, when consistent across time, are referred to as animal personality or behavioural syndromes. Explaining the occurrence of animal personality from an evolutionary perspective has however proven a difficult issue to tackle. LÄS MER

3. 7. Fattening strategies in wintering passerines

   Författare :Kristjan Lilliendahl; Innes C Cathill; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Biologi; zoologisk ekologi; Animal Ecology;

   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. 8. Food hoarding: Memory and social conditions - an evolutionary approach

   Författare :Ken Lundborg; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Djurekologi; Animal ecology; Corvidae; Paridae; dominance rank; memory; food hoarding; foraging; hippocampus; birds; behavioural ecology;

   Sammanfattning : Food hoarding is a widespread behavior among a large number of animals, and it exists in several different varieties, all of them used by the animals as a method of having a steady supply of food during periods of low food abundance such as the winter. This thesis concentrates mainly on two aspects of scatter food hoarding behavior, using small birds as study and model animals. LÄS MER

5. 9. Migration strategies of raptors – spatio-temporal adaptations and constraints in travelling and foraging

   Författare :Roine Strandberg; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; route convergence; loop migration; mortality; spatio-temporal distribution patterns; pre- and post-migratory movements; daily travel routines; satellite tracking; fly-and-forage migration; raptors;

   Sammanfattning : My dissertation is about bird migration and addresses questions about how raptors adapt to the fluctuating environments during the transition seasons between breeding and wintering. The migration is highly affected by local prey abundance, foraging strategies, weather conditions and landscape patterns along the migration routes as well as navigation and orientation mechanisms and cues. LÄS MER

7. 10. Female Reproductive Strategies in the Ruff (Philomachus pugnax)

   Författare :Katherine Thuman; Fredrik Widemo; Robert Montgommery; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Sammanfattning : Traditionally, females have been considered to be strictly monogamous. Today, we know that females in the majority of species actively seek out and mate with several males. Trying to understand female preferences, including what benefits mate choice entails, has been the focus of intense research during the last decades. LÄS MER