On the southeast coast of Australia, the town of Eden nestles along the shores of Twofold Bay. It was once a center of Australia’s thriving whaling industry, in part because it lies along the migration path of baleen whales swimming northward from the Antarctic. But residents say Eden’s whalers got some unusual help — from orcas, or killer whales, that patrolled offshore.

Locals such as Elsie Severs and Alice Otten who witnessed the hunts say the orcas took the lead in the hunt, herding larger migrating whales into the bay. Once the whales were confined in the bay, the orcas would then attack their quarry to the point of exhaustion. Human whalers moved in for the final kill — then shared the spoils with the orcas.

Discover this extraordinary story of interspecies cooperation on NATURE’s Killers in Eden.

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Online content for Killers in Eden was originally posted November 2005.

When Danielle Clode was a teenager, she came face to face with a killer. A killer whale, that is. Actually — the skeleton of a killer whale.

In the early 1980s, Clode — who is featured in NATURE’s Killers in Eden — was sailing along the coast of Australia with her parents. The family had entered Twofold Bay on the continent’s southeastern coast. There, in the old whaling port of Eden, Clode visited a museum that included the skeleton of an orca, or killer whale, that had become a local legend.

The orca’s name was Tom, and an elderly guide told Clode that Tom had once led a pod of killer whales that helped the town’s human whalers catch and kill their quarry. Indeed, the guide even pointed out wear marks in Tom’s jaws where, he claimed, the orca used to carry ropes while helping the humans.

“The guide was fantastic, and the story absolutely intrigued me,” Clode recalled recently. “I ended up doing a school project all about it.”

Years later, after earning an advanced degree in biology and becoming a science writer, Clode remembered the killers of Eden when she was looking for a book topic. Soon, she was scouring the scientific literature, trying to see if it could really be true that wild orcas — among the sea’s fiercest predators — would actually cooperate with human whalers. “There was a lot of skepticism about the stories,” she says.

Clode learned that since she had written her report as a teenager, scientists had made further discoveries about orca hunting behavior. They found that these whales have remarkably sophisticated hunting strategies, often cooperating to corner and then eat everything from schools of fish to large whales.

“They have a very good ability to take advantage of new situations,” Clode says. And that, she believes, is more or less what happened in Eden. Killer whales probably herded humpbacks and other large whales into the shallow waters, where they would then separate young or sick whales and kill them. Clode says the orcas would typically eat only the tongues, leaving most of the rest of the body behind.

In the 1980s, Clode visited a museum that included the skeleton of an orca, named Tom, that had become a local legend.

The orcas’ attacks were not without risk. “It’s a fairly dangerous activity — a big angry whale can damage a killer whale’s fins and body . . . they can end up pretty hurt.” So once the orcas learned that human whalers might spare them some of that risk it seems plausible that they learned to help out. “It may have been a kind of mutual exploitation arrangement,” she says. “Certainly the basic hunting strategies that are in the stories are similar to what’s been seen elsewhere.”

Those stories are remarkable, she says. For instance, locals such as Doug Ireland and Alice Otten state that when large whales arrived in nearby waters, the orcas would signal their human allies by “lobtailing,” or slapping their large flukes, or tails, against the surface of the water. The orcas would even lead the whalers out at night, showing the way to prey by slapping the water in the inky blackness. Elsie Severs, another eyewitness, recounts how on one occasion, her father, a whaler, fell in the water and Tom protected him from sharks. Other whalers who were drowning claimed to have been dragged back to the surface by the killer whales.

It may never be possible to authenticate such stories, the earliest of which was recorded in 1844. By the 1930s, whalers had destroyed many whale populations in the Southern Ocean, and the Australian whaling industry slowly ground to a halt. Legend has it that when a local resident killed a beached orca — in essence breaking the pact with the orcas — the killer whales also left the waters around Eden. Clode, however, doesn’t believe that’s the reason the orcas left. “It’s tempting to conclude that the killer whales started leaving after the death of Jackson [the beached orca]. And there was a loss of that trust that had built up between humans and killer whales. But it’s hard to exclude the fact that the food supply was declining; the number of whales being caught was declining dramatically.”

Clode says that modern science may explain some of those stories. For instance, it’s clear that orcas do use lobtailing as a form of communication. And researchers have found that when one member of a killer whale pod dies, the others may scatter and act erratically — perhaps also contributing to their disappearance from Eden.

But Clode is happy to report that orcas and other whales have since returned to the area. Indeed, Eden has become a draw for people who want to watch whales … not kill them.

The rich, shallow waters of Australia’s Twofold Bay — featured in NATURE’s Killers in Eden — are a whale’s dream. The bay, which lies along the migration path of baleen whales such as humpbacks, has plenty of food and protection from heavy coastal currents.

But a century ago, Twofold Bay was also a whale’s nightmare — the site of cooperative hunting between killer whales, or orcas, and human whalers. Orcas would station themselves in strategic places, waiting to herd young or sick baleen whales. Human whalers would then set out in small open boats from shore, armed with sharp harpoons and strong ropes.

According to historians, the earliest record of a whale being killed in Twofold Bay dates to 1791. Just a few decades later, in the 1820s, came the first formal whaling stations. Then, in the 1830s, whalers erected the first buildings at the port of Eden. Later, that station became the property of Alexander Davidson and his family. Their stories of the remarkable cooperative hunting behavior of Eden’s killer whales — and particularly a pod led by a killer whale named Old Tom — have captivated visitors, historians, and biologists ever since.

As early as 1903, a reporter from The Sydney Mail was writing about the unusual partnership. “When a whale is passing north it is driven into Twofold Bay by whales known as the killers,” he noted. “When the killers succeed in driving the whale into the bay they leave off the attack and wait for the whale boats to come. Any attempt the whale makes to go out to sea the killers resent with all energy by snapping pieces out of it … all the time the killers are at work.”

The growth of whaling in Eden was part of a national trend. In fact, commercial whaling was one of the country’s earliest and most lucrative industries. By the mid-1800s, Australia’s fleet was second only to America’s, capturing thousands of southern right, humpback, and blue whales a year. The whales provided everything from oil for lamps to bone stiffeners for corsets.

By 1900, however, the industry was in decline, as some whale populations began to dwindle toward extinction. By 1930, whaling had ended in Eden — an end punctuated by the death of the killer whale named Old Tom. Following a brief resurgence after World War II, whaling in Australia ceased for good in 1978. Today, the Australian government opposes the killing of whales for profit.

More whales are now returning to Australia’s coast, some to Twofold Bay, where whale watching is now an attraction. It seems that with the end of whaling, the bay has again become a kind of Eden for migrating whales.