Catch effort Analysis in Lake Manzalah (Egypt) with reference to Trammel and Seine Net-Operating Boats.

Catch effort Analysis in Lake Manzalah (Egypt) with reference
to Trammel and Seine Net-Operating Boats.
El-Azab E. B. El-Bokhty and S. M. Abdel-Hafez
National Institute of Oceanography and Fisheries, Egypt.
[email protected]
Received 29th July 2010, Accepted 26th October 2010
Abstract

Analysis of fish yields and efforts performed in Lake Manzalah during the period 1995 – 2008 were done.
Production trends of Tilapia fish revealed a decreasing trend (r = -0.8132) while those of family Mugilidae and
Clarias sp. revealed increasing trends along the period of study. The increasing trend of Clarias sp. reflects an
increasing eutrophication of the lake environment. Fluctuations of fish yields from year to another reflects the
overfishing problems caused either by increasing efforts, illegal fishing gears or both of them combined with
variations of the environmental conditions that affect the character of the trophic relations in the ecosystem of the
lake. Small boats used with trammel net operating fishermen were most lucrative than those used for seine
(surround) net operating fishermen. CPUE of both small and large boats cannot be compared without being
standardized and could be considered as initial phases of exploitation. A catch and effort data recording system
should be proposed to provide an accurate estimate of the total annual catch of the lake. Improvements of the lake
fishery should be based on many criteria which are also discussed.

Keywords: Catch, Effort, Lake Manzalah, Egypt.