Age, growth, and reproductive parameters of four species of sea catfish (Siluriformes: Ariidae) from Kuwaiti waters

Abstract

Age, growth, spawning season, and fecundity of four species of sea catfish inhabiting the northern Arabian (Persian) Gulf were investigated. These species constitute major bycatches of shrimp trawling and with lesser percentages in other fishing gears such as gill nets, gargoor traps, and hook and line setups, and most of these bycatches are eventually discarded. The most abundant catfish species found are Plicofollis tenuispinis and Netuma bilineata, while two other species, Netuma thalassina and Plicofollis dussumieri, are found in lower abundance. Length–otolith weight distribution showed a truncation in N. bilineata, which might indicate the presence of two sub-populations within Kuwait waters. Transverse sections of lapilli otoliths showed that annuli deposition occurs during the months of April and May. The von Bertalanffy parameters estimated for the four species showed that females of P. tenuispinis grow faster than males. Two presumptive sub-populations of N. bilineata inhabiting Kuwait waters showed a low growth rate population (K=0.27 y−1) and a higher growth rate population (K=0.35 y−1). The growth rate of N. thalassina was moderate (K=0.30 y−1), while the growth rate of P. dussumieri was relatively higher (K=0.34 y−1). The peak spawning season of the three major catfish species was from March to May, and data on fecundity and its relationship with body weight is presented. The fecundity of catfish species is low as is their market demand. However, the impact of shrimp trawling on the catfish population, as discarded bycatch, can have increasingly detrimental effects that on the overall population size and diversity of this population.