Paper B11

Design of Hippoid Crabs Catcher Based on Its Characteristics

Gatot Pramuhadi*1, Yusli Wardiatno2, and Ali Mashar2
1 Department of Mechanical and Biosystem Engineering, Bogor Agricultural University, Indonesia
2 Department of Aquatic Resource Management, Bogor Agricultural University, Indonesia
e-mail: gpramuhadi@yahoo.com, gph3025818@gmail.com*

Abstract

Hippoid crabs (“yutuk”) in Cilacap and Kebumen beaches were catched by local
fishermen using a traditional catching tool, namely “sorok”. “Yutuk” catching was
conducted approximately 1 kilometer along the beach with duration around 1 hour and the yield was 1 kg up to 1.5 kg. The use of “sorok” was aimed to catch burrowing
“yutuk” in about 5 cm depth sediment. The presence of “yutuk” was indicated by the
sediment bubbling, and the bubbling sediment was dig up to cacth “yutuk”. The caught
individuals were put into a basket net. Three species were caught, i.e. Emerita emeritus, Hippa adactyla, and Albunea symmysta. There was a variation in size of collected yutuk, i.e. carapace length: (1.70-5.00) cm and carapace width: (1.40-3.70) cm. A small digging experiment showed that “yutuk” could burrow into (1.50 up to 5.50) cm. The results of “yutuk” catcher prototype performance showed that average forward speed was 1.2 m/s and traction wheel slip was 9.13%. The overall prototype performance was still not good yet. The depth of catching device was up to 21 cm, so that pulling force was still too large. Trailer’s ground clearance was too low so it needed to lift it up to 16 cm from the sediment surface. Traction wheel slip was small enough for distance of 5 m from beach edge, so that the prototype could be operated well. However, for distance of 2 m from beach edge the prototype had loss its traction causing 30 cm sinkage. Screen separator mechanism was in good performance.

Keywords: Burrowing depth, forward speed, hippoid crabs (“yutuk”), traction wheel
slip,“yutuk”size.

Full Text PDF of B11 Gatot Pramuhadi et al