Habitat-preference of foraging Brent Geese (Branta bernicla bernicla) in relation to management-type

In this study the preference of foraging Brent geese is studied. The study performed on the polder of the was Dutch Waddenisland Schiermonnikoog. Wintering geese feeding in the polder are expected to prefer grazed areas due to a shorter sward, a higher protein content, a higher tiller density and less bare ground in these areas than in areas with other management types. Therefore, the expectation is that geese prefer sheep grazed grass to cattle grazed grass, which is at that time of year, ungrazed grass. In a choice-experiment, where the geese could choose between two treatments, two geese were allowed to forage on the treatment of their choice. Foraging time was used as an indication for the foraging preference of the geese. Several vegetation parameters were measured for each treatment. The geese showed a large preference for the sheep grazed areas compared to ungrazed areas. The sheep grazed area had a higher tiller density, a lower sward height and biomass and the intake rate of sheep grazed grass was higher than in the ungrazed parcels. In the sheep grazed areas nutrient intake was highest. The geese preferred grazing on sheep grazed compared to goose grazed areas. The goose grazed areas have a lower sward height, a lower biomass and a lower intake rate. Height and not treatment seems to be the major determinant a goose selects on. Nevertheless, there is a correlation between sward height and treatment this is because treatment is a way to achieve a certain grass height. Height is related to intake rate; they show an optimum curve; the geese have a preferred foraging height of the grass where they can optimise their intake rate.