Sökning: "granivorous birds"

Hittade 2 avhandlingar innehållade orden granivorous birds.

  1. 1. Costs of foraging in a dry tropical environment

    Författare :Mary Molokwu; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; foraging behavior; seasonality; predation risk; granivorous birds; food availability; water; temperature; savannah; dry tropics; energy; secondary compounds; diet selection;

    Sammanfattning : This study evaluates the costs associated with foraging for birds in a savannah woodland area in central Nigeria. Specifically, it looks at the following questions: 1) how does seasonal variability in food and water availability affect the value of resources to birds in dry environments? 2) Does proximity to water affect foraging decisions? What implication will this have in the management of savannah birds? 3) Are tropical birds mostly affected by metabolic or predation costs? 4) What factors affect diet selection in birds and how? 5) How are birds adapted to hot dry environments? I carried out experiments in the field and in an aviary and provided artificial food patches, consisting of feeding trays with seeds mixed in sand or pebbles (in the aviary study). LÄS MER

  2. 2. Effects of created habitats on farmland biodiversity

    Författare :Annelie Jönsson; Biodiversitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; agricultural intensification; brown hare; common pheasant; farming intensity; granivorous passerines; grey partridge; habitat creation; landscape heterogeneity; pollinators;

    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