WIT Press

Importance Of Juvenile Life-history Strategy To Pollutant Resistance In The Tilapias: A Subfamily Of African Cichlid Fishes

Price

Free (open access)

Paper DOI

10.2495/WP930761

Volume

2

Pages

8

Published

1993

Size

714 kb

Author(s)

P.P.G.S.N. Siriwardena, K.J. Rana & D.J. Baird

Abstract

Importance of juvenile life-history strategy to pollutant resistance in the Tilapias: a subfamily of African cichlid fishes P.P.G.S.N. Siriwardena, K.J. Rana, D.J. Baird Institute of Aquaculture, University of Stirling, Stirling, ABSTRACT Tilapiine fish can be divided into 2 groups on the basis of reproductive behaviour: mouth brooders and substrate spawners, each producing young which differ in juvenile life-history. Mouth-brooding species produce larger yolkier eggs than substrate spawners, which results in the former producing young with a more protracted juvenile development period. Although much smaller than those of the mouth brooding genera Oreochromis and Sarotherodon, the young of species of the substrate-spawning genus Tilapia were more than an order of magnitude more resistant to acute exposure to cadmium. It is hypothesised that this difference is a consequence of differences in developmental rates between the two groups and the duration of "high risk" periods

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