Journal of Ecology and The Natural Environment
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Article Number - 6B3ABFC63783

Vol.9(4), pp. 53-61 , April 2017
ISSN: 2006-9847

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Full Length Research Paper

“Diet analysis of the African clawless otter (Aonyx capensis) in and around Lake Tana”

Engedasew Andarge*
  • Engedasew Andarge*
  • Department of Biology, College of Natural and Computational Sciences, Wolaita Sodo University, P. O. Box 138, Wolaita Sodo, Ethiopia.
  • Google Scholar
Tilaye Wube
  • Tilaye Wube
  • Department of Zoological Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
  • Google Scholar
Mundanthra Balakrishnan
  • Mundanthra Balakrishnan
  • Department of Zoological Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
  • Google Scholar

 Received: 11 September 2016  Accepted: 07 February 2017  Published: 30 April 2017

Copyright © 2017 Author(s) retain the copyright of this article.
This article is published under the terms of the Creative Commons Attribution License 4.0

The diet composition of the African clawless otter (Aonyx capensis) was studied by analyzing of 440 spraint samples collected during January, 2014 and December, 2015 in both dry and wet seasons from eight sites in and around Lake Tana, North West Ethiopia. Percentage frequency of occurrence and relative percentage frequency of diet items in the spraint samples were calculated.The statistical analysis was conducted using chi-square and one-way ANOVA tests.The number of diet categories per spraint ranged from 1 to 4 with a mean of 1.42 ± 0.591. Fish was the dominant prey item in all sites with an overall frequency of occurrence of 84.77% and a relative percentage frequency of 59.68%. Labeobarbus spp. was the most frequent fish prey (35.45%). Crabs were the second most frequent prey items with percentage frequency of 33.41% and a relative percentage frequency of 23.52%, while small mammals and birds were the least frequent dietary items with percentage frequency of 0.45 and 0.23%, respectively. Other identified diet items and the respective percentage frequency were plant matter (6.17%), insects (5.68%), amphibians (5%), mollusks (2.5%) and unidentified items (3.86%). Variation on fish and crab prey items were observed between seasons and sites, while no variation was observed for other prey items. The results suggested a dietary flexibility and shift in the African clawless otter from crabs to fish that can be explained by availability and accessibility.

Key words: African clawless otter, Aonyx capensis, food items, Lake Tana.

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APA Andarge, E., Wube, T., & Balakrishnan, M. (2017). “Diet analysis of the African clawless otter (Aonyx capensis) in and around Lake Tana”. Journal of Ecology and The Natural Environment, 9(4), 53-61.
Chicago Engedasew Andarge, Tilaye Wube and Mundanthra Balakrishnan. "“Diet analysis of the African clawless otter (Aonyx capensis) in and around Lake Tana”." Journal of Ecology and The Natural Environment 9, no. 4 (2017): 53-61.
MLA Engedasew , et al. "“Diet analysis of the African clawless otter (Aonyx capensis) in and around Lake Tana”." Journal of Ecology and The Natural Environment 9.4 (2017): 53-61.

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