Reproductive biology of the small-scaled terapon, Terapon puta (Cuvier, 1829), from Lake Timsah, Egypt

Abstract

The reproductive biology of the small-scaled terapon, Terapon puta (Cuvier, 1829), from Lake Timsah, Ismailia Governorate, Egypt, has been studied during the period from June 2011 to May 2014. The results revealed that the growth of the total body weight relative to the total body length is negative allometric (b = 2.4954). Moreover, the collected fishes were divided into three age groups from one to three years. The age composition of T. puta catch indicated that individuals belonging to age group two have predominated the fish population (90.53% of the total collected individuals). The overall sex ratio indicated that the females T. puta were dominant throughout all the seasons of the year. The average values of the gonadosomatic index of T. puta were small in winter (the pre-spawning season) for both sexes, while they gradually increased in spring and summer to reach highest values in summer. The values of GSI then decreased gradually to reach minimal values in autumn (the post spawning season) for both sexes. The aforementioned data indicates that T. puta has a long spawning season that starts in early spring and ends in late summer. Moreover, the study of the fecundity of T. puta revealed that the highest significant relationship was found between the logarithmic values of both mean total body weight, and mean observed absolute fecundity, with highest correlation coefficient (r2 =0.999), consequently, the total body weight was the best indicator of the fecundity of T. puta. The recommendation of the present study is to prevent fishing of T. puta in Lake Timsah during the spawning season, which extends from April to August, or use nets with wider meshes in order to protect the spawning biomass of T. puta resources.