Ichthyofauna of Gibe Sheleko National Park and Some Morphometric Relationships of Fish of the Tributary Rivers, Southern Ethiopia

Abstract This study was carried out along a tributary of Gibe Sheleko National Park to investigate the diversity, relative abundance and morphometric characteristics of fish. By using monofilament gill-nets, fish were collected, their species identifiedand their morphometric data measured. A total of 10 species were identified, dominated overall by Synodontis schall (28.52%), followed by Labeobarbus nedgia (18.88%) and Labeobarbus intermedius (14.06%). According to the Index of Relative Importance (IRI), S. schall was also first (49.13%), followed by L. intermedius (15.49%). There were no significance differences in the IRI values of fish and relative abundance between the dry and wet season (p > 0.05). Synodontis schall had the largest girth (23.1 cm), but Clarias gariepinus had the largest eye diameter (8.4 mm) and body weight (1713.4 g). Heterobranchus longifilis was first in total fork and standard length (64.7 cm, 64.7 cm and 59.8 cm, respectively). However, the paired t test of the total body length was not significantly different from the fork length (Pn> 0.05), but not showing statistical differences from standard length, weight and girth (P < 0.05). Gibe River had a higher number of species (N) than Wabe River in both seasons. The Shannon Diversity Index (H') in Gibe River was also higher (2.09) than Wabe (1.84) during the dry season, but lowest in the wet season (1.52 and 1.57, respectively). Furthermore, both (N) and (H') were not statistically different between tributaries and seasons (p > 0.05). Generally, differences in sampling habitats and fishing effort might have contributed to discovered variants findings. Fishery development should be implemented in the Park to use the fish resource sustainably.