Title: Growth and mortality of brushtooth lizardfish, Saurida undosquamis, from Pakistani waters.
Abstract: Growth and mortality parameters of brushtooth lizardfish Saurida undosquamis (Richardson, 1848) were investigated using the length frequency data from five research trawl surveys from Pakistani waters during 2009 - 2010. The analysis was based on FiSAT computer software package. The pooled data of S. undosquamis consist of n = 870 pair of length weight data and n = 3607 length frequency data of both sexes combined with maximum length and weight of 38 cm (FL) and 492 g respectively. The length-weight relationship parameters from pooled data were a = 0.008, b = 3.000 and R 2 = 0.965. The von Bertalanffy growth function parameters were L = 39.90 cm, K = 0.270 year-1 (using ELEFAN method) and age at zero length t0 = - 0.572. Based on those growth parameters, the total mortality rate was calculated using length-converted catch curve analysis as 1.15 year-1. The natural mortality (M) was 0.687 using Pauly's equation (the annual average sea surface temperature was 27°C) hence the fishing mortality (F) was estimated by F = Z - M = 0.463 year-1. The yield per recruitment analysis indicated when tc was assumed to be 2, Fmax was estimated at 1.1 and F10 at 1; when tc was assumed to be 1, Fmax was estimated at 0.85 and F10 at 0.7. Currently age at first capture is about 1 year and Fcurrent was 0.463, therefore Fcurrent was smaller than F10 and Fmax. This indicates that the current fishery is in a safe condition. Using Gulland (1971) biological reference point Fopt was equal 0.687. The current fishing mortality rate of 0.463 year -1 was lower than biological reference point.
Publication Year: 2014
Publication Date: 2014-01-01
Language: en
Type: article
Access and Citation
Cited By Count: 14
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot