IN OCTOBER 1985, millions of people the world over followed the plight of Humphrey the humpback whale, a lost, stray, forty-ton leviathan who accidentally wandered into San Francisco Bay and swam far inland. Humpbacks were migrating south along the Pacific Coast, from Alaska to the warmer waters of Baja, Mexico, Hawaii, and beyond, but Humphrey was in danger of beaching and never making it back to the open ocean. At first, few paid attention. But as the days went by and Humphrey remained trapped, the headlines began to appear.
One chilly afternoon, I was sitting on the edge of the dolphin pool at my research facility at Marine World Africa U.S.A. in Valejo, California, feeding two young bottlenose dolphins, Pan and Delphi, when my assistant got a call. The director of the California Marine Mammal Center (CMMC), the regional marine mammal rescue center, explained to my research assistant that it was urgent that she reach me. My assistant took over the feeding of the dolphins, and with my wet hands covered in fish scales I answered the phone. Peigin Barrett, the center director and a dear friend, was speaking quickly about the forty-five-foot-long humpback whale that had swum under the Golden Gate Bridge nearly two weeks before.
Humpback whales are best known for their hauntingly beautiful songs that can travel great distances in the seas. Although the purpose of the songs remains unclear, researchers believe they have something to do with mating behavior, male-male competition, and perhaps social contact and individual identification. Imagine a population of whales spread out over hundreds of miles of ocean, their identity and relative location broadcast through song; effectively, they form an acoustic network. Humphrey had probably become separated from other humpback whales traveling south, and I wanted to help save him.
I was a science adviser for the Marine Mammal Center. I also helped rescue marine mammals. Injured and stranded dolphins and small whales were brought to our facilities, and my research assistants and I worked with a veterinarian, trainers, and other volunteers in efforts to save them. Now we faced a new challenge: an on-site rescue. Whales had been observed in San Francisco Bay waters before, but they generally made brief, albeit well-publicized, tours and then exited uneventfully. Humphrey had turned unexpectedly and wandered inland, swimming through a series of connected bays and waterways, each one smaller than the last, until he was eighty miles from the open ocean! When Peigin called me, Humphrey was swimming back and forth in the Sacramento River and into ominously small, fingerlike sloughs near the small sleepy town of Rio Vista.
The previous week, a rescue attempt using underwater whale calls had failed. Some of my colleagues, local marine mammal scientists, had conducted a playback experiment; that is, they’d played recordings of the calls of killer whales, a natural predator of humpback whales, hypothesizing that upon hearing such sounds, Humphrey would quickly depart. But it was no surprise when this approach failed. Previous playback attempts over the years using predator calls had failed to deter dolphins and whales from dangerous areas laced with fishing nets. These animals are pretty smart; apparently, they check out their environment, realize there is no true threat, and ignore the acoustic “scarecrows.”
By now, Humphrey had been in both brackish and fresh river water for a week and a half, with little or nothing to eat. The water changed the appearance of his skin. Buoyancy is quite different in fresh water than in salt water, and Humphrey had been forced to expend more energy with less food consumption. The clock was ticking. We had to get him back out to sea.
A military helicopter picked up Peigin and me at San Francisco International airport at five that evening and took us to the Operation Humphrey headquarters, a makeshift control center at a U.S. Coast Guard station near Rio Vista.
We landed in the darkness on the bank of the Sacramento River, and Peigin and I were immediately ushered into the bright fluorescent lights of Operation Humphrey headquarters. A meeting room there was already filled with federal staff from the National Marine Fisheries Service (NMFS), the National Oceanic and Atmospheric Administration (NOAA), and the U.S. Coast Guard, as well as CMMC staff and some local officials and townspeople.
A rather stiff-necked NMFS agent whom I will call Dave took charge at the front of the room and began the meeting. He reviewed the past week and a half and Humphrey’s travels farther and farther from salt water and food. But Dave stunned us when he expressed his overarching concern: If the whale died in the Sacramento River, his rotting carcass could present a health issue. Saving the whale was, it seemed, a secondary issue.
Dave then brought forth and uncovered what looked like a medieval torture device: a barbed round object on a stick. It was a radio tag that he wanted to use to track Humphrey’s location. Radio tracking was an excellent idea, but unfortunately the only tag available had to be attached to the whale by embedding the barbs into its blubber and muscle. The CMMC veterinarians and our rescue staff strongly opposed this idea. The whale was already compromised and stressed, and the barbs would only add to his problems. Dave dropped the idea—at least for the time being.
By the end of the meeting we’d arrived at a plan. The next day, with a flotilla of Coast Guard boats, a few riverboats used in the Vietnam War, and a myriad of small private boats owned and manned by local residents of Rio Vista, we would try to find the whale and form a boat barrier to herd Humphrey back to sea.
We arrived at the dock the next morning and Peigin and I were assigned to the lead boat, the Bootlegger, used by some of the CMMC staff. It was a small fishing boat owned and operated by a local fisherman, Captain Jack Finneran, who’d kindly donated his time and vessel to help in the rescue. On the boat with us was another researcher who worked with the CMMC, Debbie Glockner-Ferrari, and her husband, Mark, a wildlife photographer. Debbie had been studying humpbacks in Hawaii and could determine the sex of these enormous animals while swimming with them. We set off upriver in search of Humphrey. En route I used a hydrophone (an underwater microphone) to obtain some recordings of normal noise levels in the river. As we moved northward under the Rio Vista Bridge, I noticed that the noise level was much greater in the waters on the north side of the bridge than on the south side. This finding would play an important role later in the rescue, though I had no inkling of it at the time. Then the boat’s radio crackled: Humphrey had been spotted in a small slough near Sacramento. We raced off in the direction of the whale.
I was absolutely stunned to see this huge whale in such a small body of water, flanked on both sides by grassy fields with grazing cows.
Humphrey was an amazingly large yet graceful whale, a lost alien in this bizarre landscape. I could barely see him below the water line until he raised his blowhole out of the water for an explosive breath. We observed him slowly moving through the sloughs; to our surprise and continual frustration, Humphrey demonstrated an uncanny ability to disappear into these very small bodies of water. We tracked him by following his “footprints,” smooth, round circles on the water’s surface created by his tail movements. Yet at frequent intervals, the footprints would suddenly cease. It was weird; for hours, even aerial surveys couldn’t spot him. Our small boats seemed ineffective