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Context: Endangered pelagic thresher sharks (Alopias pelagicus) are facing high fishing pressure in many countries. As the world's largest shark fishing nation, with particularly high catch rates of thresher sharks, the impact of Indonesian fisheries has become a global priority for thresher shark conservation. Therefore, baseline data is needed to inform management and implement international agreements. Aims: This research provides data and management recommendations for data-poor targeted shark fishing in Western Indonesia, where thresher sharks are regularly caught. Methods: Daily landings data was recorded from June 2019 to December 2020 in Southwest Aceh and analysed to explore catch patterns, risk factors for thresher sharks, and potential mitigation options. Key results: Twenty-five wooden vessels of <30 gross tonnage target sharks in the Indian Ocean. We recorded a total of 109 pelagic thresher individuals during the study period, with a female-skewed sex ratio (1 female:0.39 male). Almost all pelagic threshers were caught by the bottom longline. Conclusions: Based on this data, we offer some potential management measures to reduce fisheries impacts on pelagic thresher sharks by applying a simple mitigation hierarchy framework. Implications: These results provide fisheries management recommendations, including effort limits and gear modifications. Pelagic thresher sharks are of conservation priority due to their globally endangered status. This research provides information and recommendations for data-poor fisheries in Indonesia. The results show that fishers use bottom longlines to target sharks in the eastern Indian Ocean. We offer potential management measures to reduce mortality on pelagic threshers by applying a mitigation hierarchy framework. [ABSTRACT FROM AUTHOR]

One-third of all elasmobranch species are classified as globally threatened (i.e., vulnerable, endangered, or critically endangered) according to the IUCN Red List of Threatened Species, The Sphyrnidae family, once among the most abundant shark species complexes, now faces one of highest extinction risks by the IUCN in 2019. This study aimed to analyse the total catch of Sphyrnidae in Muncar, East Java, Indonesia, from 2020 to 2023, and to evaluate the proportion of Sphyrnidae catches relative to other shark during this period. The research utilized both primary and secondary data sources, with daily enumeration conducted, using guidebooks, rulers, hand scales, cameras, code tags, plastic mats, and identification books. The results revealed that most Sphyrnidae catches over the past four years were Sphyrna lewini, with 653 females and 433 males recorded. In contrast, Sphyrna mokarran and Sphyrna zygaena were only landed in minimal numbers over the entire period. Furthermore, S. lewini accounted for less than 15% of the total shark catch, with an average of 58 shark species caught annually. The use of fishing gear by fishers operating vessels under 5 Gross Tonnage (GT) with gillnets in the 10-28 GT range with longlines was identified as significant factor influencing catch composition.”

The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Understanding wildlife markets is central to effective conservation: it can help managers and policy‐makers to predict how interventions might influence supply and demand of wildlife products, and economic welfare of wildlife users; and thus, design interventions which have better outcomes for wildlife and people. Here we apply a revealed preference method of economic valuation—hedonic price analysis (HPA)—to understand shark markets and explore the economic costs of shark conservation for small‐scale fishers. We focus on a targeted semi‐commercial shark fishery in Indonesia—which poses a threat to some shark species, but provides important economic and subsistence value for a coastal community in an impoverished region of Indonesia—and use HPA to estimate market prices and welfare measures for threatened and CITES‐listed sharks. This represents a pertinent case study with practical implications because Indonesia is the world's largest shark fishing nation, where management interventions to reduce shark fishing mortality are needed. However, such interventions will create short‐term socio‐economic trade‐offs for fishing communities, which may hamper cooperation and compliance, and raise concerns regarding the fairness and equity of conservation. Our results give significant marginal price estimates for five species of conservation and commercial importance. Dusky sharks (Carcharhinus obscurus) and bottlenose wedgefish (Rhynchobatus australiae) have the highest implicit marginal prices, at US$ 157 and US$ 144, respectively. Our estimates suggest that conservation measures, such as catch limits for endangered and CITES‐listed species, could have significant economic opportunity costs (i.e., 3.4–17.6% revenue foregone) for low‐income fishers. Innovative policy instruments are required to transform shark markets and fisheries—to effectively reduce threats to endangered species and implement CITES, whilst doing no harm to vulnerable coastal communities. Methods from econometrics can help conservation scientists to better understand wildlife markets, and make management decisions which create better outcomes for wildlife and people. [ABSTRACT FROM AUTHOR]