The Secret Life of Lobsters (21 page)

BOOK: The Secret Life of Lobsters
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What the experiments suggested to Jelle was that a robot equipped with additional sensors for detecting the direction and speed of water flow might nearly match the skills of a real lobster. No actual animal tracked odor without reference to the movement of the medium containing that odor, be it air or water. The hairs on many parts of the lobster's body detected touch or motion, so water flow was clearly a constant part of the animal's sensory experience. Jelle guessed that a lobster's antennules were involved in flow detection as well.

Jelle and a student snipped the antennule off a live lobster and clamped the antennule upright inside a sort of wind tunnel constructed from a section of clear plastic pipe. They flooded the pipe with water and, while taking high-speed film of the antennule through a microscope, ran oscillating water currents through the pipe at different frequencies. The scientists discovered that different parts of the antennule itself resonated with different frequencies, like a guitar string of varying pitch. Jelle had been an avid flutist for decades—once he'd even played a tune on an old lobster claw for an audience at a meeting of the American Association for the Advancement of Science. For Jelle, the notion that lobsters might be not just smelling but, in a sense, listening to the symphony of the ocean's currents was entrancing.

Elsewhere the quest for a robotic lobster had taken a more sinister turn. The U.S. Navy was now considering plans for a beachhead assault that would begin with thousands of biomimetic lobsters dropped offshore from low-flying aircraft. Clambering over rocks and sniffing their way through currents toward shore, the lobster robots would search out mines and blow themselves up on command. Soon the Pentagon was funding robotic-lobster research to the tune of several million dollars.

The work was carried out in a lab at the end of a narrow peninsula on the northern coast of Massachusetts, accessible only by a two-lane causeway. There, a bank of computers belonging to Northeastern University's Marine Science Center analyzed video feeds of lobsters walking on treadmills in glass tanks. Once lobster motion was translated into computer code it could be downloaded to microprocessors and fed via electrodes to artificial leg muscles made of nickel-titanium alloy. Fleets of thousands of robotic lobsters scurrying across the seafloor could have civilian applications as well as military uses, such as patrolling for pollution.

And who knew—if the natural lobster population was being overharvested and the fishery had to be shut down, perhaps the federal government could task New England's lobstermen with catching and disarming explosive automatons over which the navy had lost control. It wouldn't be that much more dangerous than what they already did for a living.

T
he old ship, a thousand tons of steel seesawing slowly on the undulating sea, groaned with the weight of the trawl. The twin electrohydraulic winches hummed with the strain of six thousand feet of metal cable. Scientists from the National Marine Fisheries Service waited under the yellow crane in the stern, bundled in orange overalls and rubber boots. They weren't sure what the net would haul up. The aft deck of the R/V
Albatross
was a thousand square feet, and the trawl could pile it ankle-deep with spiny redfish. Or it could splatter out the occasional cod, huge flat halibut, or hideous hake with its stomach popping out of its mouth from the change in pressure. The
Albatross
had once caught a streamlined gray object that looked like a shark. It was the fuel tank of an F-16.

Over the stern clanked the green metal doors that held the trawl open underwater, and the net disgorged its catch. A waterfall of silver butterfish laced with quivering pink squid spewed onto the deck. In their midst lay a mammoth lobster, each of its claws alone a foot long. Dropping to their hands and knees, the scientists sorted the butterfish and squid into baskets for counting and measurement. The lobster too would have its size, sex, and location recorded.

Owned by the U.S. National Oceanic and Atmospheric Administration, the R/V
Albatross
spends 250 days a year sailing U.S. waters in the North Atlantic, trawling for ocean life so that federal scientists can generate an ongoing census of commercially valuable species, including the American lobster.
After several weeks offshore the
Albatross
steams back to its home port at the National Marine Fisheries Service science center in Woods Hole.

Catching and counting sea creatures aboard the
Albatross
is grueling work—the shift schedule is six hours on, six hours off, twenty-four hours a day—but it can be a welcome change from the office. That is especially true for the scientists responsible for managing the lobster fishery. When they are away from their desks, off catching lobsters in the Gulf of Maine, they can escape the frustrations of managing an industry that claims there is no downside to hauling in the highest catches in history.

In 1994 Maine's lobstermen trapped thirty-nine million pounds of lobster, nearly double the historical average of twenty million pounds. Alarmed, a new committee of scientists convened and issued an official government assessment of the lobster stock, which warned that lobsters were being overfished. The fact that catches had nearly doubled was not cause for celebration, the scientists felt, but for serious concern. The situation brought to mind the history of the cod fishery, in which an exponential rise in the catch had been followed by a devastating biological and economic collapse.

Bob Steneck was worried too. The decline in superlobsters and baby lobsters that Lew Incze and Rick Wahle had seen in western coastal Maine since 1995 had continued, and nursery settlement remained dismal. Bob and his fellow ecologists were forced to ask themselves the obvious question: Had the decline been caused by a drop in the number of female lobsters making eggs?

For more than a decade, government scientists had been warning that too many female lobsters were being trapped too soon to produce enough eggs to sustain the lobster population. If that was the case, Bob reasoned, the R/V
Albatross
ought to have been catching fewer and fewer mature female lobsters when it dragged its net across the bottom. Bob contacted the National Marine Fisheries Service and asked for access to the electronic
Albatross
database so he could analyze it himself.

The
Albatross
data was of particular interest to Bob because counting large lobsters was more complicated than taking a census of baby lobsters in their nurseries. Tagging studies have proven what lobstermen have long known to be true. As lobsters mature they begin to migrate seasonally, often walking twenty miles in a year. Larger lobsters can cover far greater distances. One lobster tagged and released near the Canadian border was later caught off Rhode Island—it had jogged across five hundred miles of mountainous terrain in six months. It was these migrating monsters that Bob was after because they were the ones that produced the most eggs. The realm of the ocean they inhabited was too deep for scuba gear, but the net of the
Albatross
was capable of dragging them up.

Though Bob's tax dollars were helping to pay for the work of the
Albatross
, the reception he received from the National Marine Fisheries Service was chilly. Some of the same scientists who had disagreed with Bob during the fight over the minimum size still worked there, so perhaps it wasn't surprising. Bob pleaded with a top official at the agency, then with a congressional aide, but no data was forthcoming.

At another meeting of the Maine Lobstermen's Association, Bob got to talking with Jack Merrill. Jack had been promoted to the association's vice presidency, and he was as concerned as ever to ensure that the lobster population remained healthy. He thought that trying to obtain the
Albatross
data was a waste of time.

“I doubt the federal trawl survey would tell us much,” Jack said. The only places the
Albatross
could tow its net were in flat expanses far from shore, where the net wouldn't tangle on trap lines or rocks. “They're certainly not counting the egg-bearing lobsters that we see in our traps.”

Bob agreed that Jack might be right. The number of lobsters the
Albatross
caught in a year was about 150. That wasn't much of a sample size.

Indeed, given the limitations of the trawl survey, it was perhaps little wonder that government scientists took a dim view of the lobster population's capacity to produce eggs. One gov
ernment scientist had declared that according to his calculations, the number of V-notched lobsters in the ocean couldn't be much more than ten thousand. When Jack had heard that figure, he hadn't known whether to laugh or cry. He cut V-notches in that many lobsters himself every two years.

“It's ridiculous,” Jack complained to Bob. “One lobsterman can haul up more V-notched females in his traps in a day than the trawl survey picks up all year. Why aren't scientists counting those?”

 

The lobstermen of Little Cranberry Island had been trying to get scientists aboard their boats ever since Warren Fernald had invited Maine's commissioner of marine resources aboard the
Mother Ann
. With her coffee cans, Katy Fernald had given the Little Cranberry fishermen a way of counting V-notched lobsters themselves. Then the Maine Lobstermen's Association had begun its postcard survey, asking members to scribble down the number of eggers and notchers they caught over a two-day period every autumn. The MLA survey had now been operating for a decade, but even Jack Merrill recognized that the survey had an Achilles' heel. Anyone could argue that the lobstermen were lying.

Meanwhile, in New Hampshire, ecologists had been experimenting with other methods of surveying the lobsters that came up in traps. In the 1980s government scientists in Maine had tested something called “sea sampling.” Researchers had boarded lobster boats to record data not only about the catch, but more importantly about the lobsters that were returned to the ocean. The trials were too limited to be effective—they had operated out of only three harbors once a month—but the idea was sound. The New Hampshire scientists were supplementing similar sea-sampling trips with logbooks filled in regularly by fishermen. Checking the lobstermen's data against the sea-sampling data helped ensure accuracy.

Collaborating with colleagues in New Hampshire, Bob Steneck distributed logbooks to fishermen in Maine so they
could record the lobsters they hauled up over an entire season. Bob put his tall, blond-haired assistant Carl Wilson in charge of the project. After his first summer as an intern, Carl had become Bob's graduate student, and had developed an easy rapport with Bob's fishermen friends. But when Carl phoned the participating lobstermen to collect data, the limitations of the logbook system were apparent.

“How's your logbook coming along?” Carl would ask.

Often the lobsterman would make pleasant conversation for a few minutes, then apologize that the logbook seemed to have blown overboard. There was an exception. Jack Merrill's logbooks arrived regularly in the mail, numbers penciled in neat columns—date, depth, number of traps hauled, total number of lobsters, number of oversize lobsters, number of egg-bearing lobsters, and number of V-notched lobsters.

To supplement Jack's logbooks, whenever Bob and Carl were diving off Little Cranberry Island, Bob would call Jack on the marine radio as usual, but now they would arrange to meet at sea for a session of sea sampling. Carl would climb aboard the
Bottom Dollar
carrying a couple of plastic fish trays, a pair of calipers, and a notebook. As Jack hauled through his strings of gear he dumped the lobsters from his traps into one of Carl's trays. Carl would hunch over the lobsters one by one, measuring them with calipers and recording sex, V-notch, and egg-bearing status before handing them off to Jack's sternman.

Carl realized that most fishermen were too busy to fill out detailed descriptions of their catch. Maybe what Carl needed wasn't logbooks, but an army of sea samplers. Back on land Carl rounded up a team of summer interns and trained them in the sea-sampling protocol. In the summer of 1997 they started talking their way aboard boats up and down the coast. Outfitted with rubber overalls, heavy work gloves, life vests, and tape recorders instead of notebooks, Carl and his interns cajoled, joked, danced, and sometimes puked their way through long stints of lobster fishing aboard nearly a hundred vessels. Shouting into their recorders over the din of diesel engines, they measured and sexed several thousand animals a day.

The effort was such a success that Carl's sea-sampling program earned the institutional backing of the Island Institute and a hundred-thousand-dollar appropriation from the United States Senate. Things had come a long way since Katy Fernald's coffee cans. Jack was thrilled, and his fellow fishermen were eager to get involved. When sea samplers scheduled their next visit to Little Cranberry Island, Bruce Fernald signed up.

Bruce steamed over to the mainland first thing in the morning. Steering the
Double Trouble
toward the wharf, Bruce decided he could get used to doing science. There was nothing like pulling your boat up to the float at 6:00
A.M
. and seeing a couple of college girls in rubber overalls eager to jump aboard.

 

To Jack Merrill there was a problem with the new sea-sampling program, and he pointed it out to Bob Steneck. If Bob's goal was to judge whether the lobster population was producing enough eggs, surveying during the summer probably wouldn't suffice. It was in the autumn that the real magic happened.

Every fall Jack prepared for “the gathering of the flock,” as he liked to call it. As the first wave of soft-shelled lobsters began to migrate offshore in September, Jack pulled up his traps, untied the shallow-water ropes, stacked the gear in the stern of his boat, and set a course for deeper water. He tied on longer ropes and reset the traps in thirty or forty fathoms in the muddy valleys where the shedders would move offshore. Then, come early October, he'd see a sudden burst of mammoth females. Their shells were rough and battle-scarred. Most of them were V-notched, and the undersides of their tails were loaded with eggs.

At first, these venerable females would show up in Jack's traps in deep water—250 to 300 feet—almost as if they were coming from far offshore. He'd see a few at a time, and he'd toss them back overboard. Soon he'd see more, and in shallower water—150 or 200 feet—as if they were moving toward land like an invading army, and he'd throw them back again.
Most of them seemed to stop several miles from land and encamp there for two or three weeks. Then they turned around and headed back offshore. That's when the magic began.

For the next week or two, in late October and early November, large V-notched lobsters swarmed into traps in a massive wave heading back out to sea. As the peak of this migration passed through the fishermen's gear, each lobsterman could catch hundreds of big notchers and eggers in a single day. The animals gorged themselves on the bait and attacked anything that moved, including humans. The crusher claw of a five-or six-pound mother lobster wasn't something a fisherman could allow his hand to get stuck in, ever. Gingerly Jack would pry the V-notched mothers from his traps and drop them over the side, knowing he'd probably catch them again a few days later in deeper water.

These female hordes of autumn took a toll on Jack, whether in bushels of expensive herring or hours of hazardous handling. But they were the fishery's future. They also provided opportunities for informal research. From time to time Jack would haul up a big notcher with a message carved onto her shell—usually including a date and the initials of one of his fellow fishermen. Jack would then call his colleague on the radio to determine how far the animal had traveled. The autumn run of eggers even provided the occasional opportunity for entertainment. Once, the monotony of Mark Fernald's day was broken when he hauled up a big notcher that was dressed in a Barbie-doll outfit, complete with high-heeled sandals. Mark had to lift her skirt to see her V-notch. Another Little Cranberry lobsterman caught her again about a week later—she had walked three miles in heels.

Following the veteran females, Jack would usually witness a second surge of younger females. These were the new mothers—shiny two-pounders with unnotched tails and glistening masses of dark green eggs. These lobsters were well over the minimum legal size, and how they had escaped the fishermen's traps until now was still a mystery to Jack. But for a brief week or so, while they followed their elders offshore, the new
mothers entered traps with abandon. Jack and his fellow fishermen plucked them out, cut a V-notch in their tail flippers, and set them free.

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