Fahmi

Population connectivity shapes dispersal, genetic structure, and responses to climate change. Understanding these patterns is vital for identifying threats and improving species management strategies. In May 2024, a fisher from Indonesia with a satellite tag in their possession contacted local conservationists from non-profit organisation Project Hiu. The Project Hiu staff contacted Wildlife Computers with the serial number and successfully located the tag owner. Remarkably, the tag was identified as having been attached to a 390 cm total-length (TL) subadult female white shark (Carcharodon carcharias) in May 2012 in South Africa. Through subsequent investigations, including email correspondence and interviews with the fishers, we have determined that in November 2016, a 473 cm TL female shark (misidentified at the time as a longfin mako shark, Isurus paucus) was captured in longline gear off the coast of Indonesia, Southeast Asia. This remarkable sequence of events marks the first documented movement and connectivity of a white shark between South Africa and Southeast Asia (Indonesia). Over the 4.5 years at liberty, the shark grew in length an estimated 83 cm (18.4 cm per year), supporting previous findings on growth rates for the species. This record of events highlighted both the potential for misidentification and trade of threatened and protected shark species and the increasing benefits of close collaboration with local fishers. This newly discovered link expands our understanding of their wide-ranging connectivity among remote regions, advances our knowledge of their biology and behavior, and underscores the importance of ongoing international research and conservation efforts to protect these apex predators and their habitats.

Context: Walking sharks (Hemiscyllium spp.), native to the Indo–Pacific region, are small, benthic elasmobranchs that exhibit unique fin-assisted locomotion to ‘walk’ along the ocean floor using their fins. Although those species are not primary fishery targets, they face significant threats from fishing, habitat degradation, and exploitation for the international aquarium trade. Conservation efforts have advanced, notably with the full legal protection of all Hemiscyllium species under Indonesia’s Ministerial Decree in 2023. Methods: This review examines the ecology, fishery utilisation, and conservation status of Hemiscyllium species, focusing on Hemiscyllium freycineti and Hemiscyllium halmahera in Indonesia. Information were provided from literature reviews, government regulations and policies, interviews, and field observations. Key results: Raising public awareness on the protection status of walking sharks are needed in several locations where exploitation is taking place. The development of walking shark tourism can be one of the non-extractive utilisation efforts that may gain economic benefits for local communities. In addition, captive breeding development program can be a solution for population restoration and fulfilling the need for marine ornamental fish industry. Conclusion: Efforts to protect walking sharks must encompass comprehensive management strategies that involve local communities, government regulations, and international cooperation. The expansion of Marine Protected Areas (MPAs), habitat restoration, and developing captive breeding programs in Indonesia are essential to the sustainability of the walking shark populations. Implications: This paper advocates for integrated conservation strategies, including habitat rehabilitation, adaptive fisheries management, and community-based ecotourism, to ensure the long-term viability of walking shark populations in Indonesia.

Indonesia is home to significant populations of globally vulnerable reef manta rays (Mobula alfredi) in at least four key regions: Berau, Nusa Penida, Komodo, and Raja Ampat. Despite detailed population studies in each of these regions, little is known about their horizontal movement patterns. Our study used satellite telemetry to investigate reef manta rays’ habitat use and home ranges. A total of 33 manta rays were tagged with SPLASH10F-321A satellite tags across the four regions: Berau (n = 5), Nusa Penida (n = 8), Komodo (n = 6), and Raja Ampat (n = 14), yielding usable data from 25 tags. The rays were tracked for 7 to 118 days (mean ± SD = 50 ± 30) from July 2014 to July 2022. The results showed localized movements, strong residency near tagging sites, and high site fidelity as evidenced by area-restricted search (ARS) behaviors and frequent revisitations. Most manta rays showed restricted home ranges in each region, with no connectivity between regions. Across 25 individuals, the home range (95% utilization distributions) varied significantly, ranging from 19 to 48,294 km² (mean ± SD = 4667 ± 10,354). These findings offer important insights into the spatial movement patterns of reef manta rays in Indonesia, allowing the formulation of more effective management strategies.

Context: The taxonomic nomenclature of species can change with the discovery of a distinct species. Such nomenclatural changes occurred for the giant freshwater whipray with the discovery of a similar species in the Indo-Australian region in 2008. Aims: This paper reports a finding of the giant freshwater whipray in the Lesser Sunda region as the first confirmed record from the area. Methods: The specimen was identified as the giant freshwater whipray based on its morphological features. Morphometric measurements were taken directly in the field and also based on the scale provided in the photographs. Key results: The female specimen was recorded from the Alas Strait, West Nusa Tenggara Province, Indonesia on 20 July 2020. It was identified as Urogymnus cf. dalyensis due to its similar morphological characteristics with U. dalyensis from northern Australia but it had a shorter preoral snout and greater distance between the left and right fifth gill slits. Conclusions: The occurrence of this species in the Lesser Sunda region may confuse U. dalyensis with the close relative from south-east Asia, U. polylepis. Implications: This record may provide a link between the two species, either as a population structure of the same species or showing a clear separation between the two as distinct species.

The development of innovative technologies plays a vital role in improving the preservation and accessibility of naturalistic museum collections. These approaches also contribute to developing significant comprehensive information archives, particularly concerning endangered animal taxa, including shark and ray populations. Within this particular context, museomics can be seen as a burgeoning field of study that offers a fresh and innovative approach to the enrichment and utilization of these resources. Museomics examines genomic data from museum collections of ancient (aDNA) and historic (hDNA) DNA, including shark and ray specimens. This research aims to examine the potency of museomics in the harvesting management and conservation insights of elasmobranchs. Pre-treatment of specimens, unique DNA extraction techniques, and PCR optimization were discussed systematically. This study offers helpful information for restoring and improving the appearance of a museum specimen, which provides significant prospects for preserving biodiversity and pushing specific conservation policies for the shark and ray populations.

The University of Queensland's institutional repository, UQ eSpace, aims to create global visibility and accessibility of UQ’s scholarly research.

Sharks and rays are key functional components of coral reef ecosystems, yet many populations of a few species exhibit signs of depletion and local extinctions. The question is whether these declines forewarn of a global extinction crisis. We use IUCN Red List to quantify the status, trajectory, and threats to all coral reef sharks and rays worldwide. Here, we show that nearly two-thirds (59%) of the 134 coral-reef associated shark and ray species are threatened with extinction. Alongside marine mammals, sharks and rays are among the most threatened groups found on coral reefs. Overfishing is the main cause of elevated extinction risk, compounded by climate change and habitat degradation. Risk is greatest for species that are larger-bodied (less resilient and higher trophic level), widely distributed across several national jurisdictions (subject to a patchwork of management), and in nations with greater fishing pressure and weaker governance. Population declines have occurred over more than half a century, with greatest declines prior to 2005. Immediate action through local protections, combined with broad-scale fisheries management and Marine Protected Areas, is required to avoid extinctions and the loss of critical ecosystem function condemning reefs to a loss of shark and ray biodiversity and ecosystem services, limiting livelihoods and food security.

Genus Echinorhinus is a very poorly known group of deep-water sharks with widespread but patchy distribution in all major oceans. Echinorhinid sharks consist of two valid species, Echinorhinus brucus is reported more commonly in the Indian Ocean region than its congeneric species, E. cookei. Regular data collections in major shark landing sites in Indonesia have documented additional records of both E. brucus and E. cookei from the Indonesian waters, with updated information on their distributions in the Indian Ocean.