Short Note

Flood effects on trophic linkages of selected fish species in the littoral zone of the St Lucia estuarine system, South Africa

  • N Peer
  • NK Carrasco
  • R Perissinotto
  • SJ du Plooy

Abstract

The St Lucia Estuary, a UNESCO World Heritage Site, has experienced prolonged mouth closure since 2002. Until recently it was hypersaline, but heavy rainfall between October 2010 and January 2011 led to a large overall decrease in salinity. A stable isotope study was conducted in March 2011 on selected fish species from the nearshore environments at Charter’s Creek and the estuary mouth region to determine the influence of flooding events on their diet. Oreochromis mossambicus, the dominant fish species at both sites, had a generalised diet and occupied the lowest trophic level both before and after flooding. Monodactylus argenteus, Leiognathus equula and Gerres acinaces from the mouth area displayed a largely zooplanktivorous diet and showed some changes in prey species between drought and post-flood conditions.

Keywords: carbon, gut content analysis, nitrogen, Oreochromis mossambicus, stable isotopes

African Journal of Aquatic Science 2013, 38(3): 341–347

Author Biographies

N Peer
School of Life Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa;  Current address: Department of Zoology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
NK Carrasco
School of Life Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa
R Perissinotto
School of Life Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa; Current address: Department of Zoology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
SJ du Plooy
School of Life Sciences, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa; Current address: Department of Zoology, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031, South Africa
Published
2013-12-05
Section
Articles

Journal Identifiers


eISSN: 1727-9364
print ISSN: 1608-5914