(Table 2) Protein and fibre content of important food plants of barnacle geese (Branta leucopsis) in Adventdalen, supplement to: Kuijper, Dries Pieter Jan; Ubels, R; Loonen, Maarten J J E (2009): Density-dependent switches in diet: a likely mechanism for negative feedbacks on goose population increase? Polar Biology, 32(12), 1789-1803

• Main Authors: Kuijper, Dries Pieter Jan, Ubels, R, Loonen, Maarten J J E
• Format: Dataset
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 2009
• Subjects: Habitat; DATE/TIME; Date/time end; Species; Sample type; Sample amount; Protein; Protein, standard deviation; Acid detergent fibre; Acid detergent fibre, standard deviation; Biological sample; Determined according to Goering and Van Soest 1970; International Polar Year 2007-2008 IPY; Adventdalen; Arctic; Branta leucopsis; International Polar Year; IPY; Tundra; Spitsbergen
• Online Access: https://dx.doi.org/10.1594/pangaea.812682; https://doi.pangaea.de/10.1594/PANGAEA.812682

Goose grazing on arctic tundra vegetation has shown both positive and negative effects on subsequent foraging conditions. To understand the potential of a density-dependent feedback on herbivore population size, the relation between grazing pressure and future foraging conditions is essential. We studied the effect of increasing grazing pressure of barnacle geese (Branta leucopsis) on Spitsbergen. During the establishment of a breeding colony in the period 1992-2004, the proportion of graminoids decreased in the diet of wild geese, while the percentage of mosses increased. Grazing trials with captive geese in an unexploited area showed a similar shift in diet composition. High-quality food plants were depleted within years and over years. Intake rate declined too and as consequence, metabolisable energy intake rate (MEIR) decreased rapidly with increasing grazing pressure. During three successive years of experimental grazing, MEIR decreased at all levels of grazing pressure and declined below minimal energetic requirements when grazing exceeded natural levels of grazing pressure. This suggests that foraging conditions rapidly decline with increasing grazing pressure in these low-productive habitats. The potential for density-dependent feedbacks on local population increase is discussed. : During sampling, selective grazing by geese was mimicked by selecting only live leaf tips of every encountered plant or fresh tops of mosses. Data extracted in the frame of a joint ICSTI/PANGAEA IPY effort, see http://doi.pangaea.de/10.1594/PANGAEA.150150