Carol Warren

Indonesia has the world’s largest shark fishery, but very little locally relevant information is available on catch statistics or life history characteristics of targeted species. This poses major challenges for fisheries management and shark conservation in the region, particularly in the more remote coastal communities of Eastern Indonesia. Shark fishers from three coastal communities were interviewed and trained in data collection in their fishing grounds in the Seram, Aru-Arafura and Timor Seas. Of the over 30 species recorded by the fishers, we assessed ten species based on criteria including proportion of total catch, high intrinsic vulnerability to fishing pressure, and market and conservation value. Using a combination of fishers’ data and published life history characteristics, we estimated the intrinsic rate of population growth to evaluate the relative vulnerability of each species, and compared the observed size structure with established fisheries reference points. The interviews revealed that the fishers generally perceived sharks in their fishing grounds to be declining in numbers and size. Our study found that the fishery is catching several high risk species, such as hammerheads and guitarfish, with catches predominantly comprised of immature individuals and a high level of fishing mortality. Involving fishers in data collection and interpretation provided data and information in regions with low management and research capacity. Additionally, close collaboration with the fishers provided fundamental insights into the circumstances that shape fishers’ decision-making and the ecological and socio-economic requirements that must be addressed for management initiatives to be effective.

Small-scale fisheries in Southeast Asia are often data-poor and mismanaged due to various factors, including a lack of governmental frameworks for management and the remoteness of fishing grounds. This is particularly problematic when the target species are highly vulnerable to fishing pressure and when there is a significant dependency on livelihoods derived from the fishery. We describe the Eastern Indonesian shark fishery from three case studies in the Halmahera, Aru-Arafura and Timor Seas. Through in-depth interviews with fishers and traders we traced the origins and development of shark fishing to build the context for assessing the fishery in its present state. Catch data collected by fishers were used to assess catch composition, length frequencies and maturity of the main target species. Fishers caught a diversity of sharks, including 31 species and eight taxa from species complexes. The most frequently caught species included endangered Shovelnose rays (Rhynobatidae) and Hammerhead sharks (Sphyrna spp). Length, maturity and environmental data were recorded for 1,556 sharks, or 54% of the 2,873 sharks caught during the study. Interview data revealed changes in fishing grounds, gears and catch composition since the mid-1980s. Older fishers who had been in the fishery for over a decade generally observed greater changes in the fishery than fishers who were younger or had entered the fishery after 2003. High value species such as guitarfish (Rhynchobatidae) and shovelnose rays appear to have experienced drastic declines since the mid-‘90s, and several fishers observed an overall decline in the size of captured sharks during the last 10-15 years. These results demonstrate that fisher participation in data collection allows for basic assessments of data-poor species and identification of management priorities, particularly in fisheries thought to have significant environmental impact and socioeconomic importance, but which lack an established process for scientific data collection.

Remote rural fishing communities in Eastern Indonesia are in danger of suffering livelihood loss as a result of declining marine resources and increasing social and economic pressures, but also through management decisions which are often based solely on biological data and do not take into account the needs of local fishers. We present preliminary data from an interdisciplinary investigation of East Indonesian shark fisheries and their significance to fishing communities. Using methodologies from the natural and social sciences, we aim to identify options for shark management in the Arafura, Halmahera and Seram Seas, where shark fisheries are presumably extensive but remain largely unregulated and unreported. Through DNA barcoding of dried fin samples and by engaging shark fishers in the collection of biological data from captured sharks, we obtain vital baseline data on shark populations in fishing grounds around Halmahera in Northern Maluku and Raja Ampat, a shark and ray sanctuary in West Papua Province. Through participant observation, focus group discussions and semi-structured interviews we assess ecosystem awareness, shark fishing traditions, local knowledge and livelihood requirements in three fishing communities exploiting those fishing grounds. This study identifies the challenges of shark management in Eastern Indonesia, where current conservation initiatives threaten to displace fishing effort and negatively impact on the livelihood security of remote fishing communities. We address the contribution of this interdisciplinary, longitudinal approach to shark management in light of the biological, economic and social factors affecting a fishery that provides an important source of income but is increasingly contested globally.