We’ve learned a lot
In 2015, Conservation International scientists in Indonesia performed a first: We attached satellite transmitters to the dorsal fins of whale sharks. These transmitters had never been mounted on whale sharks because the species was simply too big to catch — so our scientists partnered with local fishermen who had inadvertently captured whale sharks in their nets, then dived in to attach the transmitters before releasing the sharks. Working with our partners at the Georgia Aquarium, we’ve learned a lot about the charismatic species, including their migratory movements and diving behavior — much of it new to science.
Whale sharks previously tracked
Our fin-mount satellite tags have a maximum battery life of two years. Here’s what we learned from sharks with decommissioned tags.
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How are sharks tagged, and what have we learned?
How are sharks tagged?
Local fishermen call Conservation International scientists when whale sharks are inadvertently caught in their nets. Before the sharks are freed, scientists attach a satellite transmitter to their dorsal fin, with minimal disturbance to the animals. The transmitters’ batteries last about two years, and data is relayed whenever the shark’s fin breaks the water’s surface.
In 2017, we downloaded 25 months’ worth of high-resolution data on diving and migratory behavior from the tag of one shark, affectionately named Sharky McSharkface — the largest data set ever recorded for this species.
What have we learned?
A satellite tag has shown that “Moby,” a 15-foot male, has one of the deepest recorded dives of any whale shark at nearly 6,000 feet — more than a mile beneath the water’s surface. Other notable findings include:
- These whale sharks (tagged in West Papua, Indonesia) are not as migratory as many believed. They disperse periodically in different directions, covering distances up to 1,000 miles, often to return to ‘home waters’ in a matter of weeks.
- They are very individualistic, going their own ways for reasons unknown. We’ve tracked two males of similar ages with utterly different migration habits, one largely staying put since we mounted his tag, while the other has ventured into the western Pacific.
- The tagging site where whale sharks feed is only a few hundred feet deep, but when they travel farther afield, they dive remarkably deep.
Conservation International’s partnership with the Georgia Aquarium
Conservation International collaborated with Georgia Aquarium to carry out health exams and blood draws on 20 wild whale sharks to provide baseline health and ensure animal welfare during our tagging research. The results have indicated that tagging does not cause additional stress to these whale sharks.
Combining the aquarium’s expertise on whale shark care with Conservation Internationals’s experience on the ground in West Papua, we are working together to ensure that whale shark tourism — a growing and lucrative industry — is managed sustainably and doesn’t adversely impact the animals’ health.
Kids adopting whale sharks
Conservation International recently launched a school program in Singapore in which students can adopt individual whale sharks and use this tool to track their progress daily, enabling them to learn about whale shark behavior and the ecosystem on which this species relies. The program aims to encourage greater awareness of the importance of healthy marine ecosystems and humans’ effect on them.
What is the Bird’s Head Seascape?
These sharks are tagged in the waters of the Bird’s Head Seascape in West Papua, Indonesia — an area that is home to a wider array of marine creatures than anywhere else in the world. These waters, spanning an area the size of Great Britain, boast 75 percent of all the world’s coral species and more than 1,700 species of fish. This rich biodiversity increases the area’s resilience to stressors such as climate change, potentially offering clues for how coral reefs can adapt to warming seas.