The drill is an Old World monkey and is listed as an endangered species in the IUCN (International Union for Conservation of Nature) red list of threatened species. Mainly due to habitat loss and a heavy hunting pressure the population has declined with more than 50% under the last 30 years. The drills are now only located in some parts of Nigeria, Cameroon and on Bioko island.  

Parken Zoo participates in the European Breeding Program for drills.