Abstract
Gorillas have a wide range of food items in their diet; fruits, leaves, shoot, roots, piths, and insects hence are considered as generalists (Caldecott & Ferris, 2005; Inskipp, 2005). There exists some wide dietary flexibility between gorilla species (western and eastern gorillas). The main focus of the study was investigating on Cross River gorilla (CRG) insectivory and its influence on habitat range suitability at the Tofala Hill Wildlife Sanctuary (THWS). This was based on the hypothesis that insectivory is a determinant to habitat suitability in Cross River gorillas. Reconnaissance survey conducted resulted to 115 gorilla signs recorded amongst which were 19 gorilla dung samples. CRG habitat was characterized by indirect signs recorded within various vegetation type, canopy cover, slope and elevation. This was in order to understand and relate habitat range and food availability. Insect food availability was assessed based on the number of insect/ant mount recorded along CRG trails. Data analysis included Kolmogorov sminorv normality test and non-parametric Spearman’s Rho correlation test to measure relationships between variables and Kruskal-Wallis test to compare groups for significant difference. Cross tabulations were accompanied with Cramers’ V-test in order to measure the level of association between 2 categorical variables most especially in cases where they were nominal. Statistical observations were discussed at the 95% Confidence Level (Alpha=0.05). Fecal analysis revealed insect foods amongst fruits (Afromomum sp., Musa sp., Marantacae sp. etc.), and leaves in THWS CRG. Results showed that insect consumption seemed to decrease with increased altitude. The weak and negative relation in number of insect parts and altitude range permits that the hypothesis of this study be accepted. Concurrently, abundance of insect parts in feces was not necessarily dependent on altitude but dependent on age, hence adopting the hypothesis that insectivory is a determinant to habitat suitability in Cross River gorillas. This study is the very first confirmation that CRGs feed on insects; Dorylus ant and Macrotermes sp. and Cubitermes sp.
Highlights
Gorillas have a wide range of food items in their diet; fruits, leaves, shoot, roots, piths, and insects are considered as generalists (Caldecott & Ferris, 2005; Inskipp, 2005)
A total of 115 Cross River gorilla (CRG) indirect signs were recorded during the study
CRG species sign distribution was greater at altitudinal ranges between 701-800m asl and the Cramer‘s V test (V=0.219, P=0.600) revealed that there is a weak and non-significant level of association between altitudinal variations observed in this study and species sign occurrence
Summary
Gorillas have a wide range of food items in their diet; fruits, leaves, shoot, roots, piths, and insects are considered as generalists (Caldecott & Ferris, 2005; Inskipp, 2005). Tutin and Fernandez (1992) emphasized on the regular and deliberate insectivorous behavior of western lowland gorillas and suggested it to be as nutritionally important for gorillas as for chimpanzees. Gorillas obtain their insect prey using their hands by digging or scratching in soil (Nishihara & Kuroda, 1991) or by breaking open nests (Cipolletta et al, 2007; Morgan & Sanz, 2006). The objective here was to investigate on CRG insectivorous feeding habits at the Tofala Hills Wildlife Sanctuary forest
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Environmental Management and Sustainable Development
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
