n African Zoology - Marine connectivity and fish length frequencies of selected species in two adjacent temporarily open/closed estuaries in the Eastern Cape Province, South Africa

Volume 46, Issue 2
  • ISSN : 1562-7020
  • E-ISSN: 2224-073X
This article is unavailable for purchase outside of Africa



The effects of timing, frequency and duration of mouth opening and marine overwash events on fish assemblages in two, adjacent temporarily open/closed estuaries were investigated. Sampling was conducted biannually over two years during summer and winter, using selective sampling gear to target estuarine-associated marine species. During this period the East Kleinemonde Estuary opened more frequently than the West Kleinemonde Estuary and it also experienced a greater number of bar overwash events when larval recruitment can occur. The timing of mouth opening and the frequency of marine overwash events did not influence species richness of marine-spawning species but had a pronounced effect on abundances (catch-per-unit-effort) of species. The species composition of both estuaries was similar, but the catch-per-unit-effort in the East Kleinemonde Estuary was more than three times greater than that of the West Kleinemonde Estuary. The East Kleinemonde also supported a greater proportion of immature individuals of and , and the length frequency distributions of both these species differed significantly between the two estuaries. The larger fish sizes in the West Kleinemonde Estuary were attributed to the prolonged mouth closure that resulted in the trapping of larger juveniles and mature fish within the estuary.

Loading full text...

Full text loading...


Article metrics loading...


This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error