Size distribution and sex ratio of scalloped hammerhead sharks(Sphyrna lewini) in Indian Ocean at southern part of Java and Nusa Tenggara, Indonesia

Hammerhead shark is one of the most common shark species in the tropics. The sharks were caught by longline and drift gill nets either bycatch or target catch. Research on the length frequency and sex ratio of scalloped hammerhead shark (Sphyrna lewini) was conducted at two shark landing sites in the southern of Java in 2010, namely Oceanic Fishing Port of Cilacap and Fish Landing Site Tanjung Luar, East Lombok, West Nusa Tenggara. Data were collected from the surveyed areas including the length of frequency and the sex composition. The research objective was to obtain data and information for management and conservation of scalloped hammerhead sharks. The results showed that the size distribution of scalloped hammerhead sharks females and males were between 51 cm to 300 cm TL and 127 cm to 244 cm TL, respectively. Sex ratio of male and female were unequal, where female caught more frequent than male. The catch during the study was dominated by the immature fishes. This condition remind that sharks resources should be managed wisely for their sustainability.