Variation in intake rate of Brent geese, Branta bernicla, depending on plant biomass and quality of the vegetation

Food depletion is a common phenomena in nature, however it is hard to measure in the field. In the case of the foraging behaviour of a herbivore, a decrease of intake rate is due depletion. In this project, intake rate has been measured in relation with biomass and quality of the vegetation. Intake rate can be measured by offering turves to the Brent Geese, Branta bernicla bernicla, and by measuring the weight loss of the turf when the geese are feeding. Peck rate and bite size, components of the intake rate, have also been measured in order to determine which variable influences mainly the intake rate.When depletion occurred, a decrease of the intake rate has been measured. A positive relation links the intake rate with the biomass. The intake rate is also dependent on the quality of the vegetation, in this study defined as fertilization of the turves. For a higher quality of the vegetation, the intake rate is higher.