the past introduction of several exotic species to the park is an additional human influence on the area. these species have damaged the natural ecosystems of killarney. the most notable of these species are the common rhododendron ("rhododendron ponticum"), which has infested large areas of the national park, and sika deer, which overgraze the woodland floor and pose a potential threat to the genetic integrity of the native red deer. both rhododendron and sika deer can have an adverse effect on the native flora by inhibiting regeneration. a more recent, accidental, introduction is the american mink, which is now firmly established in the park alongside the native otter. extinctions caused by humans include the wolf ("canis lupus l.") and the golden eagle ("aquila chrysaetos l.").