Conservation of thresher shark (Family: Alopiidae) in South‐west Aceh

Aceh province, in the westernmost part of Indonesia, is one top contributors to country's elasmobranch fisheries. Here, we discuss some proposed interventions and their feasibility towards thresher shark fisheries South-west Aceh. Fisheries managers must focus more on poverty alleviation discover alternative livelihood options reduce dependence threatened sharks coastal communities. Thresher are oceanic occupying tropical temperate seas (Compagno, 1984). They easily recognized by long tail which used stun prey. This group comprises three species within family Alopiidae; common (Alopias vulpinus), bigeye supercilliosus) pelagic pelagicus) (Gruber & Compagno, 1981; highly migratory as such, populations especially susceptible exploitation, range overlaps with many under-reported unregulated gillnet longline (Rigby et al., 2019). According last assessment IUCN Red List species, sharks' overexploited, leading depletion global population Although fins do not fetch a high price international fin market, collectively accounted for 2.3% identified Hong Kong representing between 350 000 3.9 million individual threshers annually (Clarke 2006a,b). In although trade all was regulated government 2018, they can still be traded utilized domestically (Kementerian Kelautan dan Perikanan Republik 2018). Between 2002 2011, catches were recorded largest groups national fisheries, highest catch around 50 000–60 tons per year 2004 (Fahmi Dharmadi, 2013). parts (shark ray) have existed generations become culture, also support food security (Muttaqin 2018; Booth 2021). an average 19% production. region has than 17 landing sites, where targeted concentrate west coast (Dinas Aceh, 2012; Simeon 2020). mostly caught bycatch, several operating such district, two thousand individuals rays 2020 (Ichsan 2022) . this 15 vessels open ocean regularly sites Ujong Serangga Lhok Pawoh (Figures 1 2) (Simeon temporal, spatial, effort protection approaches The number fishing efforts dependent seasonal patterns. season, June November, weather suitable fishing, whereby depart about twice month shorter days, reach up 70 trip. Meanwhile low January May, unsuitable only 15–20 trip average. Fishers ground season compared season. short, pattern determine catch, causes fishers carefully manage availability resources fuel ransom. For temporal management, will reduced if there restriction fish particular Thereby, may increase due limited period compensate loss opportunity restricted If decide grounds approach, find another location current closed. terms far from points; therefore, restrictions ignite resistance. Effort management requires strong evidence, that any modification result trade-off long-term research trials needed. However, took precautionary approach best available knowledge, it would require adaptations during implementation. our opinion, gear acceptable use main while adapting setting degree comply regulation. most likely accepted change entirely different since specialized. other forms trips or boats, responses similar income supported measure too extreme. Shark specialized longlines; however, very difficult exclude habitat behaviour. Most comprised requiem (Family: Carcharhinidae) silky (Carcharhinus falciformis) spot-tail sorrah) (Ichsan, Ula, Herman, Catches less 5% total landed (Figure 3); almost inevitable every shark-targeted 2021, 2022). Any regulation restricting specific categories (e.g., certain size class, life stage pregnancy) hardly applicable. Even though sometimes conscience regarding sustainability marine resources, admitted feel bad catching juveniles pregnant sharks; soaking hours already dead. So believe waste dead shark, means wasting rezeki ‘gift God’. Panglima Laot, local leader, currently integrates species' formal customary obey. far, generally understand obey rules stewardship resources. One example whale (Rhinchodon typus). generations, believed animal gift-bringer, smaller usually follow its sightings, rule harm them. Other examples manta (Mobula alfredi Mobula birostris) sawfishes Pristidae) fully protected Indonesia. these relatively rare, so no problem utilizing There response commercially valued (Family Alopiidae), restricted. decade, export commercially-valued sharks, cowboy longimanus) hammerhead Sphyrnidae), brought resistance misunderstanding communities traders across country (California Environmental Associates (CEA), Jaiteh, Loneragan, Warren, 2017; Rakhman, An initiative release small-scale underway Jaya, surviving nets exchange monetary compensation (Booth 2023). scheme, focuses wedgefish bycatch. Gillnet Jaya times, survival rate. promising example, adapt target species. All scenarios, location, make decrease general gain depending extent A higher value stable market commodities made lucrative livelihood. condition makes shifting livelihoods actors. Based this, options. starters, relevant partners should strengthen community knowledge awareness importance rays' ocean. After that, providing incentive scheme conservation required communities, developing simultaneously. It interesting explore influence customs spiritual beliefs behavior understood appropriately adapted, benefit rays. We thank Government, traders. ZSL EDGE Existence Programme, Fondation Segre’ WCS-IP financial technical support. colleagues, Dr. Hollie University Oxford Mr. Dharmadi Centre Research, Ministry Marine Affairs Fisheries. Open access publishing facilitated Sunshine Coast, Wiley - Coast agreement via Council Australian Librarians.