Impact of Human Activity on Whale Sharks in Indonesia

An international team of researchers has revealed the impact of human activity on whale sharks in the Bird’s Head Seascape off the coast of West Papua, Indonesia. The study showed that 62% of whale sharks suffer from scars and injuries caused by avoidable human activities, prompting the need for simple measures to reduce this burden on these gentle marine creatures.

Boat Collisions and Whale Shark Scars

Dr. Eddy Setiawan, the lead scientist at the Elasmo Branch Institute in Indonesia, explained that most scars and injuries were due to human causes such as collisions with traditional fishing platforms known as “bagans” and tourist boats intended for whale shark viewing. Minor harmless scratches were the most common, while serious injuries from natural predators or boat propellers were much less frequent.

Researchers noted that these gentle fish are exposed to such injuries due to repeated contact with these platforms or boats, often causing damage to nets.

Study of Whale Shark Distribution

Between 2010 and 2023, researchers studied the distribution of whale sharks in Cenderawasih Bay, Kaimana, Raja Ampat, and Fakfak within the Bird’s Head Seascape, which contains 26 marine protected areas and is a hotspot for marine biodiversity.

Researchers were able to identify each individual whale shark using photographs taken by scientists and interested citizens, thanks to the unique pattern of white spots and stripes on each shark. Details such as the date and time of each sighting, geographical coordinates, gender, maturity status, size, behavior, and any visible injuries were recorded.

Behavior and Residency

During this period, 268 unique whale sharks were observed, with 98% appearing in Cenderawasih Bay and Kaimana. Most whale shark sightings were near bagans, where they typically feed on baitfish like anchovies and herring. The majority of observed sharks were juveniles measuring between four and five meters, with 90% being males.

52.6% of whale sharks were re-sighted at least once, with one holding a record of being seen 34 times over three years.

Protecting Whale Sharks

With the rise in tourism related to whale shark viewing, researchers anticipate an increased risk of injuries from bagans and boats in the future unless simple protective measures are implemented. Researchers aim to collaborate with authorities managing marine protected areas to develop regulations requiring minor modifications to bagans, including removing sharp edges from boat and net frames.

Conclusion

Recent research highlights the extent of human impact on whale sharks in the Indonesian Bird’s Head Seascape, emphasizing the need for immediate action to protect them. By collaborating with researchers and local authorities, traditional fishing practices can be adjusted to reduce injuries and scars caused by human activities, enhancing the protection of these valuable marine creatures.