(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

DOI

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.

Identifier
DOI http://dx.doi.org/doi:10.1594/PANGAEA.812682
Metadata Access http://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite3&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.812682
Provenance
Creator Ubels, R;Kuijper, Dries Pieter Jan;Loonen, Maarten J J E
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 2009
Rights Creative Commons Attribution 3.0 Unported (CC-BY)
Representation
Language English
Resource Type Supplementary Dataset
Format text/tab-separated-values
Coverage
Discipline Earth System Research
Spatial Coverage (78N,17E)
Temporal Point 2003-06-30T11:59:59Z