Morphometric Characterization of African Bony Tongue, Heterotis niloticus (Cuvier, 1829) From Northern Nigeria

Morphometric characteristics of Heterotis niloticus populations from three waters in Northern Nigeria were investigated to assess their phenotypic variations. One hundred and five (105) fish samples with lengths of 14.5-43.9cm and weights of 120-780g were collected from Alau Dam, Borno State, Tiga Dam, Kano State, and Shiroro Dam, Niger State, Nigeria, and twenty-two morphological characters were measured. The data obtained were subjected to principal components, discriminant functions, and cluster analyses using PAST 4.04. Principal components analysis of morphometric traits extracted ten factors with eigenvalues greater than one. The results show that the first, second, and third PCs accounted for 63.58%, 22.01, and 7.08% variation, respectively. The cumulative percentage rate of the 1st two PC was 85.87%. Both discriminant factor and clustering analysis in morphometric characters among the Alau, Tiga, and Shiroro H. niloticus resulted in two main clusters. Distances between morphometric variables among H. niloticus populations were 97.30%. The present study revealed morphometric diversity between the H. niloticus strains of Tiga, Shiroro, and Alau Dams. This study provides basic information on morphometric variation in H. niloticus populations from the three Dams, and it could be adopted in fisheries management for conservation and sustainable exploitation of H. niloticus. Keywords: Heterotis niloticus, Dams, Phenotypic variation, multivariate analysis