ECOLOGICAL BEHAVIOURS AND MORPHOMETRIC FEATURES OF WEST AFRICAN MANATEE: TRICHECHUS SENEGALENSIS IN A SEMI-WILD
environment of Akwa Ibom state.
Akpan U. A., Egwali, E.C., and Esenowo I. K.
Department of Zoology, P.M.B. 1017, University of Uyo, Akwa Ibom.
The present study was on the ecological behaviours and morphometric features of West Africa manatee; Trichechus senegalensis, in a semi-wild environment in Akwa Ibom state and the study was conducted for 5 months; July 2008 to November 2008. The ecological behaviours of the manatee with corresponding time interval in the environment were observed and recorded using focal animal sampling method and a Diamond mechanical stopwatch. Linear and girth measurements, and body weight were recorded using measuring tape, Digital vernier caliper and weighting balance. Surface water samples were collected from the water flowing through the canal, to determine the quality of the water for the survival of the manatee. Mean time for the following ecological behaviours, bottom rest behaviour, 4.05min; feeding and surface for air, 2.35mins; rest and surface for air, 3.55 min and slow swimming, 1.40 min, were recorded. Eleven macrophytes belonging to eight families from the environment were sampled to survey the plants the manatee can forage on in the environment. Mean values of surface water temperature of 26.56±1.08oC; pH, 6.47±0.25; Free carbon dioxide, 8.83±1.44mgdm-3 ; total alkalinity, 10.35±1.85mgdm-3 ; Dissolved Oxygen, 7.35±1.42 mgdm-3 and Biological Oxygen Demand (BOD) 2.41±0.47 mgdm-3 were recorded. The morphometric features of the manatee; Trichechus senegalensis, are total length 192cm, standard length 152cm, body weight 265kg, fluke width 36cm, flipper length 36cm, head length 34cm, girth at umbilicus 120cm, girth at genital pore 82cm, girth at anus 64cm. The results indicate that the environment provides favourable conditions for the survival of the manatee.
Key Words: Trichechus Senegalensis, Ecological Behaviours And Time, Morphometric Features And Semi-Wild Environment.