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Apart from habitat type, disturbance level and tolerance of disturbance are important factors that segregate the two goose species. In autumn 1982 the majority of the Svalbard population had arrived on Filsö by 8 October, but most geese were scared off by the farmer who feared damage to his crops of winter wheat. The highest pink-footed goose (Anser brachyrhynchus) use was found on fields far away from sources of disturbance and with wide open views; these things were not so important for greylag geese (Anser anser). Greylag geese avoided the fields which were important to pink-footed, and sought out fields near roads, where the pink-footed were reluctant to go. Greylag geese tolerated a shorter flight distance towards humans and vehicles, 100-300 m vs 300-600 m for pink-footed geese (the distance increasing with flock size). The tolerance of disturbance level contributes to the niche segregation of the two species. The geese are concentrated in a relatively small area with high disturbance levels. Due to farming activities and traffic, geese are daily chased from one part of the farmland to another with a consequent concentration in large flocks.