Length-weight relationships of poor cod (Trisopterus minutus Linnaeus, 1758) in the Central Aegean Sea

Abstract

Summary A total of 1527 specimens of poor cod, Trisopterus minutus, was collected by trawl fishing between April 2001 and March 2002 from the İzmir Bay (Middle Aegean Sea). Fish size ranged from 10.6 cm total length (TL, minimum) in September to 24.8 cm TL in April. Of the sampled population 53% were males and 41% females (sex ratio female : male = 1 : 1.3). Length–weight relationships were determined for males, females and combined sexes as W = 0.007L3.16, W = 0.009L3.04 and W = 0.007L3.14 respectively.

Untitled

“…As far as the spawning period is concerned, the results of this study are similar to those obtained in different regions of the Mediterranean Sea and noted that poor cod propagate from late winter to the end of spring (Planas and Vives, 1952;Vives and Suau, 1956;Froglia, 1981;Tangerini and Arneri, 1983;Politou and Papaconstantinou, 1990;Biagi et al, 1992;Relini et al, 1999;Metin et al, 2008). This is also supported by the presence of small-size (<9.0 cm) individuals in the spring and summer catches in Edremit Bay.…”

“…While length distributions were in a range of 2.3-24.2 cm, only a few large individuals were caught during this study which are similar to that of other studies conducted in the Mediterranean Sea (Planas and Vives, 1952;Vives and Suau, 1956;Froglia, 1981;Tangerini and Arneri, 1983;Politou and Papaconstantinou, 1990;Biagi et al, 1990;Biagi et al, 1992;Relini et al, 1999;Metin et al, 2008). Larger individuals were reported by Froglia and Zoppini (1981) and Politou and Papaconstantinou (1990) over a broader area and in deeper water than surveyed in this study.…”

“…Politou and Papaconstantinou (1990) pointed out this tactic and summarized the reproductive strategy of poor cod as a combination of early maturation, extended spawning season, serial spawning, high fecundity and extensive Previous studies have shown that poor cod reached first maturity at the end of the first year of their life with an approximate size of 13-14 cm for females in different regions of the Mediterranean Sea (Froglia, 1981;Tangerini and Arneri, 1983;Politou and Papaconstantinou, 1990;Biagi et al, 1992;Metin et al, 2008). In the present study, length at maturity was estimated as 11.4 cm for females and did not correspond to other studies in the Mediterranean Sea.…”

“…This spawning strategy has been mentioned by other investigations in the Mediterranean Sea (Planas andVives, 1952, Vives andSuau, 1956;Froglia, 1981;Politou and Papaconstantinou, 1990;Biagi et. al., 1992, Metin et al, 2008.…”

“…Some of the biological studies on poor cod have included information on reproductive biology, especially in terms of spawning period and length at maturity ( (Planas and Vives, 1952;Vives and Suau, 1956;Froglia, 1981;Froglia and Zoppini, 1981;Tangerini and Arneri, 1983;Biagi et al, 1990;Politou and Papaconstantinou, 1990;Biagi et al, 1992;Metin et al, 2008). Of these studies only that of Metin et al (2008) focused on the fecundity of poor cod. .…”