PRESS RELEASE

Raja Ampat’s Walking Shark Population Records the World’s Highest Density: Evidence for the Critical Role of Coral Reef Habitat Protection

WAISAI, Raja Ampat, June 24, 2026 – A groundbreaking scientific study published in the international journal Frontiers in Fish Science has revealed surprising findings about the population of the endemic Raja Ampat walking shark (Hemiscyllium freycineti). The 14-month research project in the Dampier Strait region recorded population densities for this species, which was granted full legal protection by the Indonesian government in 2023, reaching the highest levels ever documented for the genus Hemiscyllium worldwide, with up to 2,462 individuals per square kilometer in the waters off Sawinggrai Village, Gam Island.

Read the study; “First Assessment of the life history and spatial ecology of the endemic Raja Ampat epaulette shark (Hemiscyllium freycineti) in the Dampier Strait, Indonesia”

This comprehensive study, led by a research team from Elasmobranch Institute Indonesia, BLUD UPTD Pengelolaan Kawasan Konservasi Perairan di Kepulauan Raja Ampat (Raja Ampat MPA management authority), Konservasi Indonesia, and the Arborek community, represents the first holistic effort to uncover the biology, demographic structure, and spatial ecology of the walking shark since the issuance of the protective regulation through Minister of Marine Affairs and Fisheries Decree No. 30 of 2023. Throughout the period from February 2024 to April 2025, the team successfully identified 736 unique individuals from 1,191 sightings during 64 nocturnal surveys across six locations, with the highest concentrations found around the islands of Arborek, Gam, Fam, Mansuar, and Batanta. Of the total identified population, females were found to significantly outnumber males at a ratio of 1.29:1,
while body sizes ranged from 19.4 to 75 centimeters in total length.

One of the most critical findings of this study is the role of coral reefs as the primary nursery habitat for this species. Approximately 69 percent of juvenile individuals were recorded inhabiting coral reef ecosystems, while mature sharks were more frequently found in seagrass beds and sand flats. This pattern of ontogenetic habitat partitioning underscores that protecting coral reef ecosystems is vital for sustaining population recruitment. Furthermore, the sharks exhibited extremely high site fidelity with remarkably limited spatial movements. The maximum recorded displacement was only approximately 475 meters, and not a single individual was recorded moving between islands during the study period, confirming the species’ high vulnerability to localized disturbances in their habitats.

Lead Conservation Scientist from Elasmobranch Institute Indonesia, Dr. Edy Setyawan, who is also
2025 Pew Marine Fellow, stated that the exceptionally high population density is good news for conservation efforts in Indonesia. “However, their strong attachment to coastal and shallow-water habitats makes them vulnerable to local disturbances such as coastal development and pollution. The scientific data we have collected provides the much-needed foundation to ensure that existing protective measures, such as the Minister of Marine Affairs and Fisheries Decree Number 30 of 2023 concerning Full Protection of Walking Sharks (Hemiscyllium spp.), are truly effective on the ground and not merely policies on paper,” he explained.

Despite the high population densities recorded, researchers caution that serious threats still loom, particularly from intensive tourism development, habitat degradation due to construction, and the impacts of climate change such as marine heatwaves. Studies on closely related species have shown that rising water temperatures can reduce growth rates and increase mortality in this type of shark. This makes the growth data from this study, where juveniles grow faster (7.8 cm/year) compared to mature individuals (2.8 cm/year), an important benchmark for monitoring population health in the future. Mochamad Iqbal Herwata Putra, Focal Species Senior Manager from Konservasi Indonesia,
emphasized the managerial implications of these findings. “This study provides a clear roadmap for science-based marine protected area management. By knowing precisely where they breed and where they feed, we can prioritize the protection of essential habitats. This is the key to ensuring that walking shark populations do not merely survive but thrive amidst increasing human activity in Raja Ampat,” he elaborated.

The active participation of local communities was also highlighted as a key factor in the success of data collection. Dr. Mark Erdmann, Shark Conservation Director at Re:wild, emphasized the active involvement of residents from Arborek Village who participated directly in the survey teams. “Collecting this volume of data would not have been possible without close collaboration. This demonstrates that a collaborative approach between scientists, government, and indigenous and local communities is the recipe for successful conservation in the world’s epicenter of marine biodiversity,” he stated.

Ronald Mambrasar, a man originally from Arborek Village who served as one of the spearheads of the field surveys, also voiced the profound meaning of this research for the local community. Ronald, who is also part of the Konservasi Indonesia shark monitoring team, shared how the walking shark has become an inseparable part of daily life for villagers in his village where he grew up. “For us, the Arborek community, this shark is not just a rare animal that needs protection. They are neighbors that live in our front yard. We see them every night during low tide around the seagrass beds and coral reefs. Seeing scientific data that proves their population is healthy fills us with pride, and it strengthens our determination as indigenous people to continue protecting our village and our ocean,” he said with emotion.

Welcoming these findings, the Head of BLUD UPTD Pengelolaan Kawasan Konservasi Perairan Kepulauan Raja Ampat (Raja Ampat Marine Protected Area management authority), Hasan Makasar, expressed his appreciation for the research results and affirmed his commitment to translating this data into policy. “Information regarding the density and movement patterns of these walking sharks will greatly assist us in developing sharper and more targeted management strategies, particularly in regulating tourism activities and development in coastal areas. We are committed to using this scientific data as the basis for policies to protect the endemic Raja Ampat walking shark within the
marine protected areas we manage,” he affirmed.

With this robust and comprehensive baseline data now established, the research team recommends long-term monitoring, expansion of surveys to other regions of Raja Ampat such as Misool and Kofiau, and genetic studies to understand connectivity between populations that exhibit high residency rates. The scientists hope that with this solid data foundation, adaptive and effective conservation measures can be swiftly implemented to ensure the long-term survival of the Raja Ampat walking shark for future generations.

Media contact: Edy Setyawan | edy@elasmoinstitute.id | +62 811 9697 0800

About the Research

This research is a collaboration between the Elasmobranch Institute Indonesia, Konservasi Indonesia, the Raja Ampat Marine Protected Area Management Authority (BLUD UPTD Pengelolaan Kawasan Konservasi Perairan di Kepulauan Raja Ampat), the local community of Arborek, the National Research and Innovation Agency (BRIN), and Re:Wild. This research received funding support from MAC3 Impact Philanthropies, Yacht Aid Global, Katrine Bosley, Wolcott Henry and The Pew Charitable Trusts.