Purwanto Purwanto
Research Center for Fisheries Management and Conservation, Jakarta

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

EXPLOITATION AND CPUE TREND OF THE SMALL PELAGIC FISHERIES IN THE SULAWESI SEA, INDONESIA Lilis Sadiyah; Purwanto Purwanto; Andhika P. Prasetyo
Indonesian Fisheries Research Journal Vol 18, No 2 (2012): (December 2012)
Publisher : Research Center for Fisheries

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (78.65 KB) | DOI: 10.15578/ifrj.18.2.2012.63-69

Abstract

One of the expected benefits of the Sulu-Celebes Sea Project during its implementation is to have increased fish stocks at demonstration sites, as indicated by the Catch per Unit of Effort (CPUE). Analysis of catch and effort data of the small pelagic fisheries by using the surplus yield model was done to obtain information on the likely trend of CPUE for the last ten years. By using the pajeko as the standardized fishing gear the trend of CPUE has been calculated. Between 2000-2005, the trend of production (catch), effort and CPUE followed the general pattern of the exploited fisheries that already fully exploited, where the increasing trend of effort was not followed by the increasing catch. On the other hand, the trend of CPUE is decreased. In the following years, the trend of both catch and CPUE do not follow the general pattern of the exploited fisheries. The trend of catch, effort and CPUE has likely been stable, indicating that the fishery in this period has been leveled-off. The status of exploitation of the small pelagic fish resources in the Indonesian Sulawesi Sea is demermined by the MSY level that has likely been surpassed during the period 2003-2004. Therefore with the increasing effort in the following year the trend of catch was relatively stable. It is likely that the small pelagic fish stock in the Indonesian Sulawesi Sea might be ‘fully exploited’.
PERFORMANCE OF A FISHERY HARVESTING DIFFERENT MINIMUM SHRIMP SIZES IN THE ARAFURA SEA Purwanto Purwanto
Indonesian Fisheries Research Journal Vol 18, No 2 (2012): (December 2012)
Publisher : Research Center for Fisheries

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1478.189 KB) | DOI: 10.15578/ifrj.18.2.2012.79-89

Abstract

Avoiding overfishing and ensuring the sustainability of the shrimp stock in the Arafura Sea are of prime importance for fishery management. Exploited shrimp stock consists of several cohorts, and grows considerably with age. When the shrimps are caught before the cohort has had the opportunity to achieve its optimum biomass level, the fishery will lose much of the potential benefit that could be achieved by catching them in the near future. Therefore, a bio-economic approach was developed, on the basis of the length-based Thompson & Bell model, to evaluate the impact of harvesting different size of shrimps on fishery performance. The result of analysis shows that the fishery achieved the optimal total profit when the shrimp size at first-capture and fishing mortality were 29 mm CL and 0.50, respectively. The total profit to the fishery would be sub-optimal when the shrimp size at-first-capture was smaller or larger than the optimal size. Further, it was more economical to harvest shrimps at the larger size and higher fishing mortality, and resulting in higher total profit, when natural mortality decreased.