Government sharpshooters are taking aim at hundreds of white-tailed deer in the national park surrounding the Camp David presidential retreat in Western Maryland. The move to reduce the deer population comes after nearly three decades of research and opposition from animal-rights advocates. Acting Park Superintendent Sean Denniston said shooting in Catoctin Mountain Park near Thurmont began Monday afternoon and will continue most weekday afternoons and nights through mid-March. Large sections of the park will be periodically closed, he said. Park officials say the hunt is intended to cull an outsize herd that has devoured so many saplings and low-hanging tree branches that the health of both the forest and the deer have suffered.