Effects of logging on Capercaillie (Tetrao urogallus) leks, 3: Extinction and recolonization of lek populations in relation to clearfelling and fragmentation of old forest
1989
Rolstad, J. | Wegge, P. (Norges Landbrukshoegskole, Aas (Norway). Inst. foer Naturforvaltning)
In a 136 km2 coniferous area in southeastern Norway, 13 of 24 past leks, known from the 1930-40s, went extinct and 5 new leks were established, by 1985. There was no difference in extinction rate between clearfelled (7 of 13) and untreated (6 of 11) leks. Number of leks, number of cocks per lek, and total number of cocks were reduced by 33, 53, and 69 %, respectively, compared with a 69 % reduction in suitable habitat (forest older than 70 years). We argue that the overall population decline merely was due to a general fragmentation of suitable habitats, rather than direct clearfelling of lek areas.
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