The influence of trammel net fishing on the rabbit fish (Siganus rivulatus) stocks in Suez Gulf, Red Sea, Egypt

Abstract

Trammel nets are commonly used to sample Rabbit fish (Siganus rivulatus) in Suez Gulf, Red Sea, Egypt. The present work was carried out to study the effect of trammel net fishing on Rabbit fish (Siganus rivulatus) stocks in Suez Gulf. The total 566 individuals of S. Revulatus were sampled by trammel net during October 2018, January 2019 and September 2019. The total length and total weight (TL&TW) relationship equation was obtained to be W = 0.0124 L3.0097, and total length with total girth (TL&TG) relationship equation was assessed to be G = 0.587L+1.026. The life span was estimated as 3 years. The total, natural and fishing mortality coefficients were 1.76, 0.6 and 1.16/year, respectively. The exploitation rate was estimated as 0.66. The parameters of probability of capture ensured that (25%, 50 % and 75% of fish escaped by trammel net were estimated to be L50= 15.59 cm while L25 = 14.79 cm and L75 = 16.42 cm. The results of the present study revealed that there is a marked effect of fishing on the Rabbit fish (Siganus rivulatus) stock in the Gulf of Suez, It is suggested that reducing the number of fishing trips and changing the gear characteristics (mesh size) to catch larger fish to maintain the stock productivity and its sustainability.