Integrated Management of Invasive Geese Populations in an International Context: A Case Study

Tim Adriaens, Paul Van Daele, Sander Devisscher, Frank Huysentruyt, Berend Voslamber, Vincent De Boer, Koen Devos, Jim Casaer

    Research output: Chapter in Book/Report/Conference proceedingConference Abstract

    1665 Downloads (Pure)


    Growing populations of geese exert a negative ecological, economic as well as social impact in Flanders and The Netherlands. These include invasive non-native Canada goose Branta canadensis, native greylag goose Anser anser and feral domestic goose A. anser f. domestica, among others. The EU funded project INVEXO focused on developing an integrated sustainable management in favour of both biodiversity, agriculture and the recreational sector. The approach combined efforts on prevention with ethical management methods and communication to different stakeholders and the public. Management intervened on reproduction (egg pricking) and on the number of birds (culling trough moult captures and shooting). Measures were implemented opportunistically in space and time, resulting in a mixed, diffuse deployment throughout the area. The overall impact of the combined management effort was assessed by annual counts of the geese populations in the region using a fixed sample of counting areas. Trends in the average number of geese per municipality and per year were modelled using Generalised Estimating Equations. This showed a significant decrease in the number of Canada goose since the beginning of the project. It was unclear which population response (dispersion, reproduction) was responsible for this decline. When the province of east-flanders, where moult captures were applied most intensively, was considered separately, a significant yearly decrease was noted. Moreover, incorporating the number of Canada goose caught with moult captures as a fixed effect in the model showed an effect of caught numbers on modelled estimates. Although suggesting a link between moult captures and population numbers this approach would assume other management efforts to be evenly applied over the project area, which was not the case. Moreover the number of geese in the entire area hardly decreased in the last year. Recent research indicates that Canada geese disperse over large distances within Europe, blurring effects of a local action over the years. Future work will include dynamic population modelling, as well as thorough monitoring of geese populations as the basic elements of a sound adaptive management plan for geese in the region. This requires continuous dialogue between partners and stakeholders. In this respect, the Invexo project has provided a strong impulse.
    Original languageEnglish
    Title of host publicationBiological Invasions, Ecological Safety and Food Security : The second International Congress on Biological Invasions
    Number of pages1
    Publication date23-Oct-2013
    Article numberP-051
    Publication statusPublished - 23-Oct-2013

    Thematic list

    • Invasive species (nature management)
    • Invasive species (fauna management)
    • Damage management
    • Invasive species (management)
    • Fauna management
    • Hunting (fauna management)

    EWI Biomedical sciences

    • B005-zoology
    • B280-animal-ecology
    • B390-crop-protection

    Taxonomic list

    • birds (Aves)
    • waterfowl (Anseriformes)
    • Canadese gans
    • Branta canadensis
    • brandgans
    • grauwe gans
    • Anser anser
    • boerengans
    • Anser anser f. domesticus
    • nijlgans
    • Alopochen aegyptiacus


    • management monitoring
    • biodiversity policy
    • nature management
    • species directed nature management
    • wildlife damage policy

    Cite this