The month after he arrived at Point Mugu, John Hall was cleared to high-security level and assigned to mine-detection training. Enemies could easily blockade a harbor by laying mines in shallow water or tethering them to the seabed, set to detonate in response to any acoustic or magnetic impulse from an approaching ship. Another mine-laying technique was to litter a harbor with dozens of decoy mines interspersed with a few live ones. It would take a conventional minesweeping crew days to distinguish the live mines from the decoys.
Ridgway entrusted Hall with his best open-water-trained animal, Tuffy, to test dolphin proficiency in identifying sea mines. Hall planted 48 mines in Beacher’s Bay in the Channel Islands. Within two hours, Tuffy located all 48 mines, plus five World War II–era mines that had gone astray 25 years earlier. Tuffy and other Navy dolphins could also distinguish real mines from decoys. They could even detect mines buried under six feet of sediment on the ocean floor. After just a few weeks of training, dolphins were consistently outperforming human and mechanical minesweepers.
Hall’s next assignment was to train marine mammals in Deep Ops recovery. Because the Navy frequently lost expensive equipment and weapons in deep water, it attached acoustic “pingers” to anything of value that might fall overboard as a guide to divers during recovery missions. But humans are poorly equipped to retrieve objects from the deep ocean. They can’t dive deeper than a few hundred feet; they don’t tolerate the cold temperatures at depth very well; and they can’t work for more than 12 minutes at depth before having to surface slowly and decompress. Human divers can’t see well underwater, and they have poor directional hearing, so even with the aid of an acoustic beacon, they have trouble distinguishing the location of the sound source. Dolphins, by contrast, are perfectly engineered for the task. They can hold their breath for 7 minutes and dive repeatedly to hundreds of feet with minimal decompression time at the surface between dives. Their underwater hearing is excellent, and their echolocation skills enable them to find objects hidden behind vegetation or buried in mud.
Early on in the Marine Mammal Program, the Navy investigated whether seals and sea lions could echolocate.
2
Though they turned out not to possess biosonar, sea lions proved to have acute low-light eyesight and very sensitive directional hearing underwater. And like dolphins, they are very responsive to training. One advantage that sea lions had over dolphins on recovery missions was portability. Moving dolphins to a distant dive site was an elaborate operation involving saltwater tanks and slings and several human attendants to ensure their safe transport. Sea lions could follow a trainer around on a leash like a dog, even walking on land and sitting upright alongside drivers in small motorboats en route to recovery locations.
In support of Deep Ops and Operation Quickfind, Hall trained dolphins and sea lions to first locate lost equipment on the ocean floor, and then attach lift lines or self-inflating lift bags to bring the objects to the surface. Historically, recovering torpedoes meant dispatching teams of Navy divers, recompression vans, and medical personnel. Hall trained his sea lions and dolphins to recover torpedoes lost at depths of up to 800 feet.
For recovery missions at greater depths, the Navy turned to deeper-diving marine mammals. Following the debut of orca shows at marine parks in California early in 1968, Ridgway commissioned Ted Griffin of Namu Inc. to capture two killer whales for the Navy Marine Mammal Program. In October a Navy transport plane flew Ahab and Ishmael to Point Mugu, where they became the first orcas to be trained in the open ocean. Ridgway also bought a deep-diving pilot whale named Morgan from a local fisherman who had snared him off the coast of Catalina Island.
Hall soon trained Ahab to locate and retrieve objects from depths of 800 feet. Morgan, the pilot whale, could dive twice as deep. While their biosonar was just as discriminating as that of dolphins, orcas proved less obedient to commands in the open water. Ahab had a habit of disappearing at sea for days at a time, and Ishmael finally went AWOL one afternoon during training exercises, never to return. Since killer whales were judged too unreliable to handle torpedoes, Hall designated the pilot whale for the Deep Ops retrieval program. On one notable occasion, Morgan located a torpedo at 1,800 feet and attached a hydraulic lift bag that raised it safely to the surface.
• • •
In 1969, North Vietnamese frogmen were infiltrating the port at Cam Ranh Bay and attaching explosives to the sides of American ships. As a countermeasure, Hall trained the Point Mugu dolphins for “swimmer interdiction.”
Hall, equipped with a snorkel and a rebreather, played the enemy swimmer trying to penetrate Mugu Lagoon without being detected by the bottlenose sentries. Once he’ d trained the dolphins to ram intruding swimmers with their snouts, Hall never made it anywhere close to the beach before being intercepted. Several cracked ribs later, Hall flew eight of the bottlenoses and one pilot whale to Hawaii aboard a specially equipped cargo plane, and then on to Guam for final operational training.
In early 1970 the five best-performing guard dolphins arrived at Cam Ranh Bay. The Navy anchored three catamarans with netted dolphin pens hanging between the pontoons across the mouth of the wide bay at 9:00, 12:00, and 3:00. The dolphins were trained to continuously scan their sector of the bay and to press a black or white paddle with their snouts every two minutes: white for “all clear,” black for “swimmer in the water.” When a dolphin pressed the black paddle, the door to the pen would open and release the animal into the bay. Before leaving the pen, the dolphin would press its snout into a custom-fitted fiberglass nose cone armed with a barbed steel hook that protruded from the front. The dolphin was trained to quickly track down the swimmer, stab him in the buttocks or the upper thigh with the barbed hook, pull out of the nose cone, and return to its pen. The nose cone was designed to rapidly inflate and jettison the swimmer to the surface, where Navy SEALs in high-powered black speedboats would swoop in for the capture. The swimmer saboteurs, drawn from the ranks of North Vietnamese army officers, were considered high-value interrogation subjects.
The system worked flawlessly for the first few interdictions—until the swimmers began carrying hand grenades and tossing them into the approaching speedboats. The SEALs eventually designed countermeasures to prevent grenade attacks, and, after losing several highly trained saboteurs to the dolphin/SEAL patrols, North Vietnam stopped sending swimmers into Cam Ranh Bay.
• • •
While its “swimmer nullification” program remained classified, rumors and reports continued to circulate about the Navy training “kamikaze dolphins” to kill enemy swimmers with antishark explosive devices and .45 caliber “bang-sticks.” The Navy denied using dolphins to target enemy swimmers with lethal force. But over the decades since the end of the Vietnam War, interviews with former Navy animal trainers and CIA operatives detailing these programs appeared periodically in newspapers, magazines, and books—as well as a Navy SEAL who described working with dolphins to plant limpet mines in North Vietnam’s Haiphong Harbor.
3
One reason rumors of these extreme kamikaze dolphins persisted is that Lilly proposed just such a scenario in
Man and Dolphin:
If they are military types they could be very useful as antipersonnel self-directing weapons. They could do nocturnal harbor work, capture spies let out of submarines or dropped from airplanes, attacking silently and efficiently and bringing back information from such contacts. They could deliver atomic nuclear warheads and attach them to submarines or surface vessels and to torpedoes and missiles.
Both the popular media and contemporary politics lent credence to stories about dolphin dark ops. The 1973 Mike Nichols film
The Day of the Dolphin
featured a fictionalized John Lilly character, played by George C. Scott, whose Caribbean research center is subverted by shady intelligence officers who train his dolphins to plant explosives under enemy boats. Two years later, the Church Senate Committee hearings into extralegal CIA operations uncovered plans that were developed—although never deployed—to assassinate Fidel Castro by training dolphins to deposit explosive-filled conch shells in a cove where the Cuban leader liked to snorkel each morning.
1973
Marine Corps Air Station, Kaneohe Bay, Hawaii
Bionics had finally come of age, at least in popular culture. From 1974 to 1978, actor Lee Majors reigned as the first bionic TV superstar in
The Six Million Dollar Man
. His character, US astronaut Steve Austin, had been critically injured in a crash and was “put back together again” with bionic replacement parts that endowed him with superhuman vision, strength, and speed.
After the United States withdrew from Vietnam in 1973, the focus of the Navy’s marine mammal research shifted from “What can they do?” to “How can we build technology to replicate what they do?” As Hall and Ridgway had demonstrated, dolphins consistently outperformed human divers and existing sonar technology for guarding harbors and detecting mines. But dolphin crews were expensive to maintain and difficult to transport around the world.
The Navy hoped it could gradually replace its high-maintenance dolphins with bionic drones. On a broader level, it wanted to reverse engineer dolphin echolocation to improve existing sonar technology. In 1970 the Navy drained the porpoise pool at Point Mugu and relocated its marine mammal biosonar research to the Marine Corps Air Station at Kaneohe Bay in Hawaii. Sam Ridgway moved to San Diego to oversee cetacean physiology research, while John Hall decamped to graduate school at UC Santa Cruz, where he befriended Ken Balcomb and Bob Gisiner.
In Hawaii, an electrical engineer and experimental psychologist directed a team of acousticians and statisticians to develop bionic sonar.
4
The more they learned about dolphin biosonar, the more daunting their bionic design challenge appeared. Dolphins could collect, assimilate, and interpret an astounding amount of data, and they could do it amid the acoustic complexity of the open ocean. And dolphin signal processing exceeded anything that computers could replicate in the 1970s.
Research into dolphin hunting behavior in the wild offered tantalizing clues for designing the kind of short-range, high-frequency sonar systems that might someday replace dolphins as minesweepers and harbor sentries. Dolphin biosonar operates in a highly mobile and adaptive fashion, with decisions about next actions flowing out of real-time assessment of streaming information. When the Navy searched the sea, it ran a grid in straight lines on a regimented schedule. But a dolphin continues to adjust its swimming pattern and sonar algorithm as it goes, circling an unknown object, scanning it from different angles to create a three-dimensional model, sorting relevant data from extraneous data, and, finally, extrapolating historical data points to arrive at accurate judgments about a target: Is this fish going to taste good or make me sick? Is this an armed mine, or a decoy?
Navy researchers confirmed Lilly’s early observation that dolphin sleep occurs in one brain hemisphere at a time, while the other hemisphere continues to scan the environment for data—in much the same way that an antivirus program continues to scan a hard drive even when the drive is “sleeping.” But duplicating the dolphin’s continuous learning cycle required a level of artificial intelligence design that lay decades in the future.
Another avenue of biomimicry research examined the group-learning dimension of dolphin biosonar—what today would be called “crowd-sourced intelligence.” As herd animals, dolphins in the wild are constantly pooling and exchanging their search data. The closest analogy would be the modern internet search engine, which scans oceans of data using specific terms, tags, and criteria, while simultaneously incorporating a steady stream of user search requests, past and present.
5
In the eighties, the Navy moved closer to deploying its dolphin drones, which it called Autonomous Underwater Vehicles, or AUVs. They
looked
like dolphins in size and shape, and were equipped with multibeam sidescan sonar that approximated dolphin biosonar. But the AUV had a gaping hole in its motherboard where a real dolphin’s “wet brain” lives and works. After a quarter century of close observation, Navy researchers had learned a lot about the dolphin’s physical and neural anatomy but very little about its mind and how it made judgments. Despite the early confidence of naval engineers that they could manufacture a bionic dolphin, the “advanced biologicals,” as the Navy referred to its marine mammal recruits, had been evolving their biosonar for 30 million years—too big a head start, it appeared, to overcome in just a few decades.
• • •
In 1986, in the wake of the John Walker–Jerry Whitworth spy trial, the Navy persuaded Congress to amend the Marine Mammal Protection Act to allow the Navy to collect dolphins in the wild for unspecified “national defense purposes.” The Navy’s marine mammal menagerie swelled to more than 100 dolphins, dozens of sea lions, and a supporting cast of beluga whales recruited for deep dives in Arctic waters.
In 1987, for the first time since the Vietnam War, the Navy redeployed dolphins as seagoing sentries—this time in the Persian Gulf. When Iran began mining the harbor in Bahrain to disrupt oil tanker traffic, the Navy dispatched six dolphins to clear mines, protect US warships against enemy swimmers, and escort Kuwaiti tankers in and out of the harbor. Many of the dolphins couldn’t handle the sudden transition from the cold water of San Diego to the extreme warmth of the Gulf. One named Skippy died of a bacterial infection. The Marine Mammal Program was still classified at the time, but news of the dolphin deployment in the Persian Gulf leaked to the media.
When the
New York Times
and other outlets reported that the Navy was endangering dolphins to protect Arab oil tankers, the animal rights movement mobilized in protest. A year later, the Navy proposed deploying dolphins to guard the Trident missile submarine base at Bangor, Washington. When animal advocates sued the Navy over the health risks of moving the San Diego–based dolphins to cold northern waters, a judge ordered the Navy to study the issue, and the Navy abandoned the project.