keywords: Molluscs, biodiversity, species richness, conservation, National park, Taraba
Gashaka-Gumti National Park (GGNP), Taraba State, is one of the largest parks in Nigeria known for Biodiversity Conservation. It is characterized by a wide variety of habitats and species currently threatened by deforestation, poaching and effects of global warming. Terrestrial molluscs, Species Richness and Diversity in Gashaka-Gumti National Park were studied for the first time using a combination of direct search and leaf litter sieving technique. A twenty-four plot (20 x 20 m) each within the park were sampled. A total of 1594 specimens comprising 22 species belonging to six molluscan families were collected from four plots. Each plot yielded between 3 and 12 species (mean = 7.96 ± 3.06) and 3 to 688 individuals (Mean = 66.42 ± 34.82). The most abundant species was Curvella feai contributing about 60% of the total number of individuals occurring in Park. The most abundant family is Streptaxidae represented by 7 (32%) species and 82 (5%) individuals of the total sample. The Whittaker Index was 1.75, indicating low differentiation among plots. The rarefaction curve reached an asymptote as sampling stopped. The nonparametric estimator Chao 2 and jack-knife 2 were 22 and 22.96 of all samples collected, respectively. The dendogram of similarity by plots using Bray-Curtis similarity of index divided the species collected into 3 distinct groups at 50% similarity. This study has succeeded in highlighting information on the state of abundance of the identified land snail species in the study area so that conservation agencies can swing into action with a view to protecting the integrity of these species that are of moderate abundance of which if steps are not taken may face extinction.