Ecological factors influencing nest survival of hazel grouse Bonasa bonasia in a temperate forest, South Korea

The survival of 86 clutches laid by hazel grouse Bonasa bonasia hens was studied using radio telemetry to evaluate the importance of key vegetation variables for nest survival between March 2003 and June 2009 in a 3000 ha study area of temperate forest in South Korea. The nest sites in the forest stands differed from that in the study area with dense understory cover and low visibility. Daily nest survival rates increased with understory cover, higher proportion of natural deciduous forest, and decreased with nest conspicuousness. Nest survival rates were not correlated with tree density, basal area, mid-story cover, and overstory cover. The results did not reveal any differences in the daily nest survival rate between first breeders and older hens. Habitat management that protects the remaining understory cover and natural deciduous forest is key to stabilizing threatened hazel grouse populations in temperate forests.

► Nest survival of hazel grouse were studied in southern edge of their distribution.
► Understory cover and natural deciduous forest were important factors influencing hazel grouse nesting.
► Understory cover and natural deciduous forest should be considered in forest management for conservation of hazel grouse.