76 10(2): 076-082 (2016) Journal of FisheriesSciences.com E-ISSN 1307-234X © 2016 www.fsheriessciences.com ORIGINAL ARTICLE Research Article * Correspondence to: Assefa Tessema, Wollo University, College of Natural Sciences, Department of Biology, Dessie, Ethopia, Tel: +0331114247 E-mail: atecklie@yahoo.com Abundance and Fish Species Compositon of Gerado and Dirma Rivers, South Wollo, Ethiopia Assefa Tessema and Adem Mohamed Wollo University, Department of Biology, Dessie, Ethiopia Received: 26.02.2016 / Accepted: 23.04.2016 / Published online: 30.04.2016 Abstract: Abundance and fsh species composition of both Gerado and Dirma Rivers were studied in dry and wet season from February to November 2014.The objectives of the study were to assess fsh species composition, relative abundance and recommend sustainable fshery management to help biodiversity conservation in aquatic ecosystem. Gillnet with mesh size of 6-10 cm were used to catch the fsh species, sensitive balance was used to measure weight of the fsh in gm and Ruler was used to measure total length of the fsh species in cm . Shannon diversity index was used to compare species diversity in both rivers between seasons. Univarate analysis and t test were used to test species composition and abundance difference in both rivers between sites and season through application of SPSS Version 16 .In both rivers , abundance and fsh species composition were more in dry season than wet season. The Shannon diversity index(H') value were 1.78 and 1.66 in dry and wet season respectively for Gerdo river and 1.61 and 1.41 in dry and wet season respectively for Dirma River. The dominant fsh species in Dirma and Gerado Rivers in dry season was Varcohinus beso with total number of 128 and 129 respectively. The dominant fsh species in wet season in Dirma River was Labeobarbus intermedius (40) whereas Varcohinus beso was dominant in Gerado River(25). The total fsh species composition of Dirma River was more (6) in dry season than wet season(5).The total fsh specimens collected in Drima River was more in dry season (236) than wet season(77).The species composition of Gerado River was higher (8) in dry season than wet season (6).The total fsh specimen collected in Gerado River was higher (199) in dry season than wet season(37).There was signifcant difference in abundance of fsh specimens between season and site (P<0.05) un like non-signifcant variation in Shannon diversity index value (P>0.05) between rivers. Keywords: Abundance; Season; Shannon Index; Species Composition