The saltwater crocodile is a great, stealthy, archaic beast that you wouldn’t expect to pacify with a little friendly tickle on the tail. But here is Daisy, a seven-foot Australian saltie on a grassy shore of the Wenlock River, as placid as a Pekingese. She’s being petted by 11-year-old Robert Irwin, who is stroking the lower third of her thrashing anatomy. Fortunately, a blindfold, gaffer tape and a rope muzzle ensure the amity of this relationship.
“It’s an honor and a privilege to work with the largest living reptile and largest terrestrial predator on the planet,” Robert tells me in the singsong tone of his television-ready family. “An awesome animal that roamed the primeval landscape for millions and millions of years.”
Daisy’s sawtooth tail whips the prone boy to the left. “The jaw pressure of the crocodile is incredible—3,000 pounds per square inch!”
Daisy’s tail whips him to the right. “I so admire the crocodile’s ability to kill with just its teeth. It’s quite amazing!”
Robert’s 16-year-old sister, Bindi, looks on solicitously. An actor, singer, game show host and, last year, a People cover girl, she’s confirming Daisy’s gender by inserting a finger into its cloaca and feeling around for genitalia. “It’s a girl!” she says. Her smile conveys a disarming buoyancy. “Here’s an animal that many people think is just a stupid, evil, ugly monster which kills people. That’s so not true!”
Bindi and Robert are the offspring of Steve Irwin, the boisterous, can-do naturalist of “Crocodile Hunter” fame. Perpetually clad in khaki shorts and hiking boots, the elder Irwin’s shtick—provocative, up-close interactions with wild animals and squeals of wonderment (“Crikey!”) at their magnificent deadliness—made him an international TV phenomenon. Irwin’s encounters with lethal animals ended in 2006, when a stingray’s barb pierced his heart while he was filming on the Great Barrier Reef. He was 44.
It’s late morning on the Wenlock and the odor of rotten meat hangs in the air. A feral pig carcass was used to bait the trap, one of 17 set along this 30-mile stretch of the river. The clean, bright sun has filtered a warm benediction down onto the bank, where Robert and Bindi; their mother, Terri; and a team of animal wranglers from the family-owned Australia Zoo are taking part in an extraordinary zoological study. For more than a decade researchers have monitored the behavior and physiology of saltwater crocs in Queensland, mainly at the Steve Irwin Wildlife Reserve, a 333,000-acre floral and faunal sanctuary on the Cape York Peninsula. The park was created by the Australian government as a living memorial.
What’s perhaps surprising is that Irwin, though controversial for his flamboyant hands-on approach to wildlife, quietly teamed with serious scientists and conservationists to make a genuine contribution to the systematic natural history of this enigmatic critter. Their discoveries about the salties’ habits, homing abilities and private lives have prompted a rethink of how they live and how we can coexist with them. Adult crocs have no natural predators except people, possibly because we’re meaner.
At a time when nature preserves are becoming more intensively managed, and zoos and aquariums are becoming more involved in field conservation, the line between “the field” and “animal holding facility” has blurred. By straddling both worlds, Irwin was smack in the middle of the quandary over the trade-off between protecting animals in the wild and studying them in captivity. Today, that quandary is further complicated by his family’s link to SeaWorld, harshly criticized since the 2013 documentary Blackfish for its treatment of killer whales and the subject of a withering new book by one of its former trainers.
The research project that Irwin helped launch is led by Craig Franklin, a University of Queensland zoologist, who, using capture techniques developed by the Croc Hunter, has trapped, tagged and released scores of salties in Aussie waterways. Data gathered by satellite and acoustic telemetry is beamed to a Brisbane lab, which maps the beasts’ whereabouts and logs their dive times and depths. The project is bankrolled by the Irwins’ zoo, federal grants and private donors—a little over $6,000 gets you the “exclusive naming rights” to a wild, caught croc.
Far from being just sedentary, solitary animals with one dominant male defending a set territory, as once thought, salties also turn out to be far-ranging creatures with complex social hierarchies. “Crocodiles are misunderstood because they’re not cute and fluffy,” says Bindi, a mainstay of Franklin’s annual field trips since Day 1.
When the blindfolded Daisy lets out a long, low growl, Bindi flashes a smile bright enough to illuminate the Sydney Opera House. “Crocodiles are very vocal, quite intelligent and so, so capable of love,” she says. “When an adult female rests her head on her mate’s stomach, there’s no way to describe it but love. They protect their babies and their homes and they have the most delightful sense of humor.” Then again, you may need to be a crocodile to fully appreciate its badinage.
There’s something inscrutable and prehistoric about the crocodile, as if it were designed by a committee of slightly ticked-off paleontologists. Its name derives from the Greek krokodeilos, meaning “worm of the stones.” Australian stone-worms lurk large in Dreamtime, the animist framework of Aboriginal mythology. The Gagudju people of Arnhem Land believe that Ginga, a spirit ancestor who helped create the rock formations of the region, underwent a transformation after accidentally catching fire. He dashed into the water to extinguish the flames and rough, lumpy scars formed on his back. He became the first crocodile.
Aboriginal people have traditionally hunted crocodiles for their meat, but the animal’s population remained stable until World War II ended and high-powered rifles became widely available. Commercial hunters and trigger-happy sportsmen slaughtered them indiscriminately. Since given protection in Australia during the early 1970s, their numbers have rebounded, then boomed to about 100,000.
Of the 23 crocodilian species, two inhabit the rivers, billabongs and mangrove swamps of the Australian tropics: the freshwater, or Johnson’s, crocodile, which is relatively harmless, and the formidable estuarine, or saltwater, croc, which can grow to 20 feet in length and weigh more than a ton. The range of the two overlaps somewhat, and sometimes the bigger and far more aggressive saltie will make a hearty lunch of the freshie.
Robert Irwin got it right: Salties are ruthlessly efficient killing machines. They come equipped with nearly 70 interlocking teeth, many as sharp as a steak knife. If one breaks off, there’s another underneath to replace it. Numerous muscles close the brute’s jaws but only a few open them.
Over the last 70 million years not much has changed in the saltie’s evolutionary design. This archosaurian behemoth can see well by day and by night and has three pairs of eyelids, one of which functions like swimming goggles to protect the croc’s vision underwater. Another membrane holds the tongue in place, preventing water from filling the lungs, which is why, even in contempt, the crocodile can’t stick it out.
Salties stalk their quarry with deadly patience—over days if necessary—learning its habits and feeding times. The croc skulks below the surface near the water’s edge, poised to ambush anything it can clamp those jaws on—cattle, wild boar, kangaroos, even other crocodiles as they come to drink. In a constant state of awareness, they’ll reveal themselves and strike only when confident of success.
Lunging and chomping, the saltie executes the death roll: Spun around by a corkscrew snap of the tail, the body twists and flips while the wrenching torque is absorbed at the powerful junction of head and neck. The disoriented victim is dragged into deeper water and drowned. Rather than swallow its meal immediately, the croc occasionally wedges what’s left under a rock or log to allow it to decompose, returning later to feed again. Croc rules where crocs rule: Keep your claws off my prey.
Not for nothing are salties called man-eaters. On average they attack and eat one a year in Australia. Last year they took three. Their sensitivity to human routine is downright unnerving. As Bill Bryson wrote in his down-under travelogue In a Sunburned Country: “The chronicles of crocodile killings are full of stories of people standing in a few inches of water or sitting on a bank or strolling along an ocean beach when suddenly the water splits and, before they can even cry out, much less enter into negotiations, they are carried away for leisurely devouring.”
The worst devouring was reported in 1945 during the Japanese retreat in the Battle of Ramree Island in the Bay of Bengal. British soldiers encircled swampland through which the Japanese were withdrawing. Nearly 1,000 soldiers are believed to have been munched to death by the resident salties.'