Determination of the home range of endangered drill monkeys (Mandrillus leucophaeus Cuvier, 1904) in Afi Mountain Wildlife Sanctuary, Nigeria

Abstract

Home range is an area in the habitat that an animal habitually carries out its daily activities. The endangered drill monkey (Mandrillus leucophaeus Cuvier, 1904) is highly terrestrial primate that forages on the forest floor extensively for its food. It is on this note that this study was undertaken to determine the home range of the drill monkeys in Afi Mountain Wildlife Sanctuary, Nigeria. Drill monkeys’ groups were followed at reasonable distances to avoid detection by the drills. Garmin 72 GPS was used to record GPS coordinates at first contact, either visually or acoustically as well as the daily distances covered. The study was carried out from January to December, 2020. Drills were encountered eighty-five (85) times either visually or acoustically; it was not possible to document all the encounters using the GPS due to equipment failure or bad weather. Hence only 45% of such encounters were documented. Five (5) large drill groups were identified, three (3) groups with overlapping home ranges in the north and two (2) groups without overlapping home ranges in the south. The home range of the drill groups in the north was 20km²while that of the drill groups in the south was 15km2. Statistical test of significance showed no significant (p= 0.05). it was recommended that further study using other more scientific methods such as the use of drone technology and radio-telemetry are needed for detailed study of drill monkeys home range in the study area.