The effect of group-selection forest harvesting on the physiology and reproductive output of breeding ovenbirds (Seiurus aurocapilla ).

摘要

Group-selection forest harvesting disturbs the interior of the forest. In this study I investigated the effect of two methods of group-selection ('intensive' and 'typical') and un-harvested controls on the physiology and reproduction of a forest interior species, the Ovenbird (Seiurus aurocapilla ), breeding in Algonquin Provincial Park, Canada. Blood samples were taken from adult males and nestlings to examine baseline corticosterone. A standardized capture and restraint protocol was applied to males to examine stress-induced levels. Males had similar baseline levels across treatments but higher stress-induced levels in intensive sites. Nestling birds had significantly higher baseline levels in the intensive treatment compared with the control. There was no significant effect of harvesting on nest survival; however, broods were male-biased in the intensive treatment. The results from this study show that individuals in different life stages vary in their susceptibilities to harvesting. I propose that typical group-selection may be less detrimental than intensive.;Keywords: Ovenbird, Seiurus aurocapilla, group-selection, silviculture, breeding, glucocorticoid, corticosterone, stress response, environmental stress, habitat disturbance, Algonquin Provincial Park