Estimates of Demidoff's galago (Galagoides demidovii) density and abundance in a changing landscape in the Oban hills, Nigeria

• Published in: Hystrix Vol. 31; no. 2; p. 117
• Main Authors: Omifolaji, James Kehinde, Ikyaagba, Emmanuel Tersea, Abideen Abiodun Alarape, Ojo, Victor Abiodun, Modu, Mala, Lewiska Funmilayo Lateef, Muhammed Adewole Adeyemi, Ahmad, Shahid, Luan, Xiaofeng
• Format: Journal Article
• Language: English
• Published: Varese Associazione Teriologica Italiana 01-01-2020
• Subjects: Deforestation; Habitats; Land use; National parks; Population; Population decline; Population density; Rainforests; Small mammals; Nigeria
• DOI: 10.4404/hystrix-00342-2020
• EISSN: 1825-5272
• ISSN: 0394-1914

Galagos are one of the understudied family of nocturnal primates which inhabit much of Sub-Saharan Africa, some of which are potentially at risk of habitat loss due to deforestation. The rainforests of West Africa are home to six species of Lorisoidea; however, this habitat is under threat from an increasing human population and anthropogenic activities land conversion for agriculture, amongst other pressures. This study assessed the distribution of Demidoffs galago under different land use pattern in Oban sector of Cross River National Park. Line transect methods were used to estimate the density of Demidoffs galago in a human-influenced forest and an otherwise similar and relatively undisturbed forest. Galagos are mostly observed in canopy forest, secondary forest and farm fallow with a total number of 27, 21, and 14 sightings respectively after survey efforts of 72 km. The encounter rates for the three habitats were 0.56 km-1, 0.35 km-1 and 0.23 km-1 for close canopy forest, secondary forest and farm fallow respectively. Close canopy forest habitat has the highest estimated density of about 0.24 km2. The estimated density of secondary forest habitat is approximately 0.23 km-1. The proportion of total sighting of the species across the habitats varied from 43.55% in the close canopy forest habitat, 33.87% in secondary forest habitat and 22.58% in the farm-fallow habitat. The result indicates that the Demidoffs galagos density was significantly lower in farm fallow habitats (n=14, df=2, F=2.26, p=0.009) compared to close canopy forest (n=27, df=2, F=7.616 p=0.999). Higher population density and encounter rate observed in the close-canopy forest may be due to less habitat disturbance and less susceptible to population decline. It is, however, necessary to maintain the environment in its present state and to continue population monitoring over an extended period.