Spear gun fishing in shallow and deeper water of coral reefs in Weh Island, Aceh, Indonesia

抄録

Artisanal fishing on coral reefs in Weh Island, Aceh is an important livelihood activity, and most people there have a high dependence on the coral reefs. Spear gunshave become one of the most effective itemsto be used in this area because of itscheap, easy to use and no by catch dynamics, and has also evolved to become a recreational activity. The objective of this study is to examine aspects of spear gun fishing activities in the shallow and deeper waters of this area and its impact on the reef fisheries in Weh Island, Aceh. Data were collected from 13 fish landing sites in seven villages. Fish catch analyses, thecorrelation between fish lengths and trophic levels and the comparison of fish catch and biomass were among various methods used in this study. Fish catch data, such as the total of catch (kg), species name and measured fish lengths by photo and fishing grounds were collected using photographs during October-November 2008 and May 2009. In addition, fish size structure and biomass estimations were sampled using visual census methods. There are two kinds of spear fishing operated in Weh Island. These was spear gun fishing with a snorkel which was operated in shallow waters and spear gun fishing with a compressor which was operated in deeper waters. From the total of spear gun fishing trips in Weh Island, 60 % was dominated by spear gun fishing with a hookah compressor. The total of fish caught from both spear gunswith a hookah compressor and a snorkel was 100 species within 20 families, with evidence for the dominant family Serranidaeat 55.48%. A total of 1004 individuals were collected. The total number of individual that were caught by all spear guns was dominated by groupers, where Cephalopholisminiatawas the highest proportion with 24.4% and followed by Epinephelusfasciatus 5.98%, Cephalopholisargus 4.68% and Cephalopholissonnerati 4.38%. The total weight of species was dominated by groupers as well, especially for Cephalopholisminita with 13.4%. There was a significant difference of catch per unit efforts between spear guns operated by a snorkel and spear guns operated by a hookah compressor (P<0.5). Beside from the total 100 species caught by spear guns, 75% was caught by spear guns with a compressor and 50% were carnivores.