Factors influencing the development and mortality rate of shy and cat shark embryos in South African waters

Pretorius, Carrie Ann

Factors influencing the development and mortality rate of shy and cat shark embryos in South African waters

Master Thesis

2012

Publisher

University of Cape Town

Department

Department of Biological Sciences

Faculty

Faculty of Science

Abstract

There are at least 500 species of sharks inhabiting the world's oceans and very little is known about the reproductive biology of most of these species. By observing Scyliorhinids, which exhibit oviparous reproductive behaviour, we can further understand the nature of elasmobranch reproductive behaviour, including embryo growth and development. Two Scyliorhinid species endemic to South African waters are investigated here, Poroderma pantherinum, commonly known as the Leopard catshark and Haploblepharus pictus the Dark shyshark. Observations were made both in the field and in the laboratory to ascertain differences in reproductive behaviour. In the field P. pantherinum laid their eggs at an average depth of 15.7 m - ? 28.8 and their preferred choice of substratum, onto which their eggs were singly attached, were seafans. H. pictus, on the other hand, laid their eggs at an average depth of 3.9 m - ? 15.9 and their preferred choice of substratum, onto which they attach their eggs predominantly in pairs, was the seaweed Bifurcariopis capensis.

Description

Includes bibliographical references.

Keywords

Zoology

Reference:

Collections

Masters

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