Annual fluctuations of reproductive indices in Blue swimming crab (Portunus plagicus, Linnaeus, 1758) in Persian Gulf (Case study, Khuzestan Province coasts)

Bahador, Mina; Haghi, Mahsa; Kochanian, Preeta; Movahedinia, Abdolali; Hoveizavi, Shafa

doi:10.22059/jfisheries.2020.300795.1160

Annual fluctuations of reproductive indices in Blue swimming crab (Portunus plagicus, Linnaeus, 1758) in Persian Gulf (Case study, Khuzestan Province coasts)

Document Type : Research Paper

Authors

Mina Bahador ¹

Mahsa Haghi ²

Preeta Kochanian ²

Abdolali Movahedinia ³

Shafa Hoveizavi ¹

¹ -

² Department of Fisheries, Faculty of Marine Natural Resources Khorramshahr University of Marine Science and Technology Khuzestan Province, Iran

³ Department of Marine Biology, Faculty of Marine science, University of Mazandaran, Babolsar,, Iran.

10.22059/jfisheries.2020.300795.1160

Abstract

Blue swimming crab is one of the most important crustacean and known as a commercial species in subtropical areas. This study investigated the reproductive biology of blue swimming crab, Portunus pelagicus. Sampling was run monthly through trawl catches in the Khuzestan coast, most of the specimens were catch at the Bousif fishing site, from April to March 2017. A total of 567 crabs were collected of which 221 were males and 346 females, with a male: female ratio of 0.6:1. The carapace width and weight ranged from 60.9-164mm and 15.2-387.7g in males and 67.5-174mm and 18.3-434.1g in females, respectively. The mean carapace width was 119.37±1.59mm and 130.15±1.32mm and mean weight were 135.58±5.92g and 156.54±4.49g in male and female crabs, respectively. Body weight was significantly higher in female crabs (about 15%) (P<0.05). Gonadosomatic index was the highest in March. Also, the number of ovigerous females was the highest during May-June. The results of correlation between egg mass and total body weight showed that egg weight was more related to carapace width than body weight. Totally, it seems that the blue swimming crab has optimum reproductive environmental condition in Khuzestan coasts and could reproduce several times a year on these coastal waters. Therefore, it is possible to be a potential for export economy.

Keywords

sex ratio

maturation stages

P. pelagicus

ovigerous females

spawning