Epsilon Archive for Student Projects

Abstract

The level of neonate mortality in a free ranging fallow deer (Dama dama) population at the Koberg estate in south western Sweden was investigated using radio-tracking techniques. During this study a total of 36 fawns (17 ♂, 19 ♀) were captured and marked with vhf or gps radio collars; 12 fawns in 2008 and 24 fawns in 2009. The neonate mortality calculated by the Kaplan-Meier method was 23.6 % and the mortality caused by predation was low, since only 1 of 8 non-surviving fawns died from predation by red fox (Vulpes vulpes). The spatial behavior of the fallow deer neonates were examined at two different levels i.e. the habitat selection within their home-range, which would in fact be a selection made by the mother, and the bed-site selection within that habitat. Compositional analysis revealed a significant preference for the habitat classes arable land, pasture and coniferous forest between 5 - 15 m compared to the habitat class young forest. Visibility and canopy cover were estimated for selected and random bed-sites for fawns marked in 2009, and as expected the selected bed-sites showed significantly lower visibility and higher amount of canopy cover than the random sites. However, since there are few predators in this study area and predation pressure is low, this behavior is not connected to actual survival rates in this area, but would rather be an adaption to a previous history of higher predation pressure. This persistence of anti-predator behavior under relaxed selection is referred to as the "ghost of predators past" hypothesis.