Karakteristika ved to territorier for hvitryggspett Dendrocopos leucotos i Telemark
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How to Cite

Heggland, A. (2004). Karakteristika ved to territorier for hvitryggspett Dendrocopos leucotos i Telemark. Ornis Norvegica, 27, 80-85. https://doi.org/10.15845/on.v27i0.198

Abstract

I investigated two territories of the White-backed Woodpecker Dendrocopos leucotos situated in Skien and Notodden (Telemark). The territories are situated in the far east in the range of the Norwegian Sørlandet population. One territory (Notodden) was situated in a stand of grey alder. The amount of fallen and standing dead trees was investigated using two census plots. The density of fallen and standing dead trees (mostly grey alder) was 324 and 137 truncs/ha, respectively. A well defined area covering 33 ha of high quality foraging habitats represents an estimate of the home range during the nestling period. The other territory (Skien) was situated in a landscape where decidous forests are heavily fragmented. All suitable foraging habitats (stands of decidous forest with high density of dead and dying trees) were mapped within the area 0-3 km from the nesting site (a circular area of 28 km2). Patches of decidous forests occurs as 1-10 ha patches in a matrix of clearcuts and young stands of spruce. Decidous forest makes up only 4 % of the total area. The area within 1 km from the nest site showed the greatest abundance of suitable foraging habitats (480 ha, 15,4 % of the total area), while the density of suitable foraging habitats declined further away from the nest site. Changes in forest structure leading to reduced amount of suitable foraging habitats on a landscape level is believed to be the main reason for the decline in the population of the White-backed Woodpecker in eastern parts of Norway, as well as in Western Europe as a whole.

https://doi.org/10.15845/on.v27i0.198
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