“It starts with really basic demographics: How many are there? Where do they give birth? Where do they mate? Where are all the big males? Where are all the small females?” Dove says.

Which is where a two-man team from Conservation International that joined Dove—Mark Erdmann, vice-president of Asia-Pacific marine programs, and Abraham Siantar, the organization’s local shark and ray specialist—come in. Cenderawasih is unusual in that its whale shark population is not seasonal, but present all year round. It is also isolated: Getting there even from the Indonesian capital of Jakarta means a minimum of three hops on a plane and a long boat ride. That makes the bay, a wide expanse of sheltered water speckled with pristine reefs and home to dozens of unique species—several of which Erdmann, a veteran marine biologist, first described—a kind of laboratory for studying whale sharks.

At night, the bay glitters with the bright white lights from bagans, a traditional Sulawesi fishing platform made up of a central hull fitted with wooden outriggers and strung with nets and lines. The lights draw in baitfish, which in turn attract whale sharks. Sometimes, the sharks get caught in the nets. A few years ago, brainstorming ways to fit bulky, long-lasting satellite tags onto the sharks’ dorsal fins, Erdmann and Siantar settled on the bagans. “It struck us: This is a golden opportunity to have a whale shark in a constrained environment,” Siantar says.

Since 2015, Conservation International, a nonprofit based in Virginia, has fitted more than two-dozen fin-mounted tags on whale sharks in Cenderawasih. They uploaded videos of the work to YouTube, where Dove noticed a striking similarity between the way that the wild sharks sit in the bottom of the bagan nets and the way that the Georgia Aquarium’s four captive animals relax into the vinyl slings that the aquarium uses to perform veterinary exams.

The two organizations started to exchange emails, and after a year of planning, they chartered the Putiraja, a wood-framed, white-hulled cruiser out of Sorong, and sailed to Cenderawasih in late July. Once anchored in the bay, Siantar boarded a motor launch just after sunrise each morning to do the rounds of the bagans. Promised a bounty of 1 million rupiah ($75) per shark, local fishermen lured the animals into their nets with handfuls of baitfish, churning up the water with buckets as the sharks drifted in slow orbits around the platforms.

Once an animal crossed into the net, Dove, Erdmann, and Siantar joined it. While Erdmann took photos of the shark’s distinguishing features, Dove got a hold of it, stretched out along its flank in something halfway between a wrestling move and an embrace. Individual sharks reacted in different ways. Some sit still at the bottom of the net; others, like the juvenile male Dove swam with, struggled, thrashing their tails and writhing as the divers clung on.

Peter Guest

Once he had a solid grip, Dove had to find a vein in the shark’s pectoral fin, a rigid slab covered in skin an inch thick, and insert an 18-gauge needle, the kind used by doctors to put a spinal tap into a human. It often took several goes—“It’s basically a blind stick” Dove said. Blood congeals quickly in the tropical heat, so as soon as the syringe filled up, Dove swam back up to hand it off to a colleague in a waiting speedboat, which powered across the bay to a makeshift lab set up on the stern of the Putiraja.