The Secret Life of Lobsters

by Trevor Corson

  Jelle knew nothing about lobsters, but a bit of lore he’d picked up intrigued him. Old-time fishermen claimed that a brick soaked in kerosene would attract lobsters to a trap. What better way to begin a study on the effects of petroleum products on undersea organisms than to test this theory? Hoping that his investment would pay off, Jelle purchased a supply of lobsters from the local fishermen’s wharf.

  Soon Jelle had confirmed that lobsters were attracted to the hydrocarbons in petroleum products such as kerosene. But that discovery would tell him little without an understanding of how odors and tastes governed the behavior of lobsters. Searching for food, socializing, and selecting mates were obvious aspects of lobster life that might rely on water-borne chemicals. Mate selection in particular, Jelle thought, could be revealing.

  Smell is an important part of sex for any animal that releases pheromones, including humans. But little was known about how sex pheromones worked in creatures such as insects or crustaceans. All Jelle had to go on was a German study of silkworm moths. The female moth sits in a tree and emits her scent. The male moths catch the scent and fly upwind in a race to reach her. Jelle guessed that lobster mate selection might work similarly. The female lobster would find a place to perch and emit her scent, and the males would sniff her out and come running. The first one to reach her would win.

  But Jelle also guessed that some sort of special sex pheromone, and not just any female scent, might be required to induce lobsters to mate. Most of the time, male and female lobsters couldn’t stand each other. Prior to the molting season Jelle had paired a male and female lobster in a tank. Immediately the animals had grown agitated and flicked their small antennae rapidly. The small antennae, called antennules to differentiate them from the large antennae, serve as an underwater nose; flicking them is the lobster’s way of sniffing.

  Detecting each other’s scents, the male and female both opened their claws wide and raised them overhead, then whipped the water with their large antennae in a tactile search for the offending odor. The belligerent shoving and snapping of claws that followed made Jelle glad he wasn’t in the tank along with his subjects.

  Before attempting to mate any of his lobsters outright, Jelle devised a preliminary test. Since females usually mated immediately after molting, perhaps they released a special sex pheromone when they shed their shells. When Jelle’s first female molted, he bailed some of the water from her tank into a tank occupied by a male. From the presence of the water alone the male grew agitated, but in a manner quite distinct from what Jelle had observed in his earlier experiment. This time the male sniffed with his antennules, but instead of opening his claws and raising them overhead he closed and lowered them. Instead of adopting an aggressive stance he stood delicately on tiptoes. Instead of hunting cautiously he probed the tank with abandon.

  Sadly, he would never find the female that had aroused his libido. Her scent lingered maddeningly in his tank, but by then Jelle had lifted her tender, defenseless body into the tank of another male.

  Observers of the natural world as far back as Aristotle have wondered how lobster sex works. In the fourteenth century the Italian philosopher and physician Simone Porzio wrote that the lobster’s “organs of sex and reproduction are constructed in such a way that I cannot discover any obvious way in which the seed of the male could be ejaculated, poured, or otherwise introduced into the body of the female.” The problem was that the male lobster appeared not to have a penis.

  Later investigators thought they had discovered the secret of this vexing omission in the male lobster’s swimmerets. Male and female lobsters both possess these little fins, arranged in five pairs along the underside of the tail. But the male’s first pair, located at the midriff, are quite unlike those of the female. Instead of the flexible, flattened flippers that adorn the rest of his tail, the male’s first pair are hard and pointy. Perhaps it wasn’t that the male lobster was missing a penis, but that he had two.

  In the 1830s the French naturalist Henri Milne-Edwards, who gave the American lobster its scientific name of Homarus americanus, put an end to this speculation. The male lobster’s two members, Milne-Edwards wrote, couldn’t possibly penetrate the female, on account of their small size. At best, Milne-Edwards thought, the first pair of swimmerets might be “exciting organs”—tools of foreplay.

  But leaving female lobsters frustrated wouldn’t do, so Milne-Edwards hypothesized the existence of a huge penis that the male kept hidden away except during intercourse. Similar to a collapsible telescope, this membranous appendage would emerge on demand, formed by an erection of the walls of the seminal tube inside the male’s abdomen. But the collapsible penis turned out to be a fantasy. By the 1890s the world’s first great lobster scientist had set things straight.

  Francis Herrick, a graduate student in the zoology department at Johns Hopkins University, was studying snapping shrimp when he chanced upon the lobster for comparison. Snapping shrimp are essentially miniature lobsters. The snap in their name originates from their claws—they stun their prey with the sound of an air bubble popping between their snapping pincers, which clap together so quickly that they emit a flash of light. The American lobster is slower on the draw and can’t dazzle anyone with fireworks, but Herrick would come to believe that it did have two penises after all.

  The question that most intrigued Herrick about the lobster’s sex life was whether the female fertilized her eggs internally or externally. In 1850 a French naturalist named G. L. Duvernoy had speculated that lobsters never copulated; instead, the male simply fertilized the eggs externally when the female extruded them from her body onto her tail. Herrick didn’t believe Duvernoy’s hypothesis was correct, but he felt the Frenchman was onto something. Where previous scientists had noted the absence of a lobster penis, Herrick had noted something else—the female lobster’s lack of a vagina.

  Without a vagina, internal fertilization was impossible. Herrick turned his attention to another part of the female’s anatomy. At the base of the female’s tail, near the same place that the male lobster had his two hardened appendages, she had a tiny pouch. Herrick realized it was a seminal receptacle, where the female could store a male lobster’s sperm until she was ready to extrude her eggs. This gave the female lobster the advantages of both internal and external fertilization. Instead of having to entice a desirable male at the exact moment she extruded her eggs, as Duvernoy had proposed, she could adopt a more opportunistic approach to copulation, mating whenever a desirable male was available. But she also avoided the burdens of pregnancy. She simply kept the sperm on hand in a kind of fanny pack. When she was ready to squirt the eggs out onto the underside of her tail, she unzipped the pouch and performed the external fertilization herself.

  Given the position of the pouch, it seemed obvious to Herrick that the male’s pair of hardened swimmerets were involved in the transfer of sperm. The appendages didn’t need to be long for deep penetration, because the female’s receptacle was on the outside of her body. But the skeptics had been correct to point out that the swimmerets weren’t exactly penises. They didn’t contain hollow tubes necessary for delivering sperm.

  But a groove did run along the inside edge of each swimmeret, and their pointed tips matched the size of the hole in the female’s receptacle. By dissecting lobster testes, Herrick discovered that the male lobster wrapped his sperm up into gelatinous, tubular capsules called spermatophores. He noted that the duct delivering sperm from the testes opened exactly at the base of the hardened swimmerets—“as if,” he wrote, “they served for conducting the spermatophores through the elastic, slit-like orifice of the seminal receptacle.”

  In essence Herrick had gotten it right. Later researchers confirmed that the male brings his hardened swimmerets together to form rails like a train track, the pointy tips propping open the female’s receptacle. Sperm packets are ejaculated through the seminal duct and guided down the rails into the pouch. The trailing edge of the final spermatophore hardens to form a plug
that blocks the opening in the seminal receptacle, preventing another male’s sperm packets from entering. It isn’t exactly a penis-and-vagina situation, but it’s pretty close.

  Herrick spent five years writing a 250-page treatise titled The American Lobster: Its Habits and Development. Published in 1895, it was the first in-depth study of the species. In the text he seems to lament the fact that the lobster misses out on the pleasures of internal copulation. For comparison Herrick describes the mating of crabs, where the male crab runs to the female, embraces her, pulls her to his belly, and ceremoniously penetrates her with his penis.

  Herrick needn’t have worried. He did his best work on lobsters at a seaside laboratory in the little town of Woods Hole, Massachusetts. Many decades later, working in the same location, Jelle Atema discovered that the American lobster could be a most tender lover, penis or no.

  When Jelle’s freshly molted female flopped into the new tank, she was so soft she couldn’t stand. She didn’t need to, however, because the male came to her.

  Jelle was worried. This female was his first defenseless subject; having just shed her shell, she was without protection. Jelle hoped the male wasn’t simply going to brutalize her, as he might have normally. Jelle was betting that a special sex pheromone, the presence of which he’d still only hypothesized, would do the trick.

  Again, the male responded immediately to the soft female’s scent. Sniffing with his antennules, he closed and lowered his claws, stood on tiptoe, approached the female, and circled her. As he circled he began to stroke the female’s soft body with gentle sweeps of his large antennae.

  Not only was the male not going to brutalize her, he evidently had an enormous reserve of patience, for his circling and stroking continued for another quarter of an hour. Finally the female raised herself to a standing position. This indicated, Jelle guessed, that her shell had hardened just enough for the male to handle her safely, and sure enough, the male now mounted the female from behind. Pressing his tail flippers and claws to the floor of the tank for support, he grasped her body underneath his with his walking legs and rotated her onto her back. The two lobsters lay face-to-face, as it were, with the male on top. Both lobsters fanned their soft swimmerets against each other in a flurry of excited stroking. Jelle caught a glimpse of the male’s hardened swimmerets pressed against the female’s abdomen and saw him thrust several times. Apparently, lobster sex occurred in the missionary position—but with double the male genitalia.

  The male dismounted and the female flapped her tail to right herself, then backed into a corner of the tank to rest. The male backed into another corner and adopted a similar attitude of repose. Jelle looked at his stopwatch. After fifteen minutes of foreplay, the act of copulation had taken eight seconds.

  Jelle concluded that a molting female lobster must indeed emit some sort of chemical signal that alters the behavior of male lobsters. When Jelle had lowered the female into the tank, the male had been transformed from a belligerent bully into a solicitous master of the boudoir. Whatever constituted this perfume of love, it was a powerful drug.

  Jelle repeated the experiment with other lobsters. Sometimes the recently molted female wasn’t in the mood and resisted the male’s advances. Undeterred, the male would continue to circle and stroke the female’s body with his antennae. Jelle termed it a courtship dance, and if the male kept it up long enough he usually managed to persuade the female to let him mount her.

  The opposite situation occurred too. Even when the male wasn’t interested, the female might sidle up and attempt to slip under him. The tactic didn’t usually succeed, but the males refrained from any violence. Something about the presence of the molted female inhibited them from fighting even when it didn’t excite them into lovemaking.

  Jelle laced an empty tank with female molt water and then dropped in a hard-shelled male and a hard-shelled female, neither of whom had any romantic interest in the other. The two lobsters began an angry quarrel. Just when Jelle was afraid one of them was going to lose a limb, the drug from the absent female began to take effect. The lashing of the male’s antennae calmed to a gentle stroking, and the female allowed him to fondle her. Within a few minutes, the goal of beating the female up had become less interesting to the male than the prospect of mounting her, which he attempted several times. The female offered little resistance. She wasn’t ready to mate, and nothing came of the male’s advances. But the experiment demonstrated how the smell of a molting female alone could modify lobster behavior.

  Jelle repeated the experiment, this time with two hard-shelled males. But even a strong dose of female molt water wasn’t enough to evince signs of homosexual lobster love. Indeed, with the scent of a willing female wafting between them, the males were more antagonistic than ever.

  That suggested a larger pattern. No one had ever seen lobsters mate in the wild, but Jelle imagined how it might work. A female lobster about to molt would seek protective shelter—under a ledge, in a crevice, between two boulders. She would huddle in her hiding place and shed her shell, emitting her sex pheromone into the flowing currents of the sea. A bevy of excited males downstream would catch the scent and scramble upstream to her den, dueling each other for the privilege of courting her. The winner would enter, initiate foreplay, and be rewarded with the opportunity to deposit his sperm packets in her pouch.

  Jelle was delighted. His theory of lobster mating matched the German model for silkworm moths perfectly. There was only one problem. His theory would turn out to be almost completely wrong.

  4

  The Man Show

  Ann Fernald was taking a casserole out of the oven when a crowd of men tramped in through the front door. A rush of frigid air followed them.

  “Hi, boys!” Ann called from the kitchen. She heard her husband’s voice from the den.

  “Come on in and take your boots off,” Warren said. “And shut that damn door.” The men laughed.

  Warren had added both leaves to the dining-room table. Ann carried two more serving dishes from the kitchen and worried that the table wouldn’t be long enough. She had places for Bruce, Mark, and Dan, along with Jack Merrill and several of the other young men who’d come to the island to go lobstering, as well as her three younger children—fourteen settings in all. That would be enough plates, but would there be enough to eat? She’d peeled an entire sack of potatoes. Warren and Ann had made a habit of inviting Little Cranberry Island’s cohort of young lobstermen over for dinner, but Ann was still surprised at how much food they could consume after a day of hauling traps.

  Jack came into the kitchen.

  “Hey there, Ann,” Jack said, giving her a kiss. She patted his ruddy cheek with her stove mitt.

  “Can I give you a hand?” Jack asked.

  “I think everything’s just about set,” Ann said. She glanced back at the counter. “Oh, Jack, be a dear and bring in the peas.”

  Twenty years earlier Ann had come to Little Cranberry Island kicking and screaming. She’d married Warren at eighteen, very much in love, but when he brought her to his island she was miserable. He provided her with food and shelter, but there wasn’t much other than winter to be sheltered from—many of Warren’s generation had left Little Cranberry, and the place felt nearly deserted.

  When Warren started drinking, things got worse. Ann had already given birth to two sons who needed a father when, on the day the third son was born, Warren was so drunk he fell out of Pa’s Pride into the harbor. By the time Ann had four children Warren was leaving the house some mornings with a lunch pail in one hand and a six-pack of beer in the other. Finally the alcohol had so depleted the vitamins in his body that he had an anxiety attack at the dinner table. He ran from the house and locked himself in his workshop. He had never built a lobster trap so fast in his life.

  Ann confronted him that night.

  “Enough,” she said, pouring a glass of whiskey. She informed him it was the last drink he was ever going to have. Warren had been sober ever since.


  Now Ann surveyed the throng of young lobstermen in her dining room and smiled. After two decades of feeling lost, she’d finally found home. And who knew, things might turn around for the island. Two or three of Warren’s contemporaries had stayed on Little Cranberry and had sons who were lobstering. Three of Warren and Ann’s four sons had become fishermen. The confines of the island could still feel like a curse—one of the Fernald daughters packed her suitcase at the age of fourteen and fled the place, and part of Ann couldn’t blame her. But between Ann’s sons and their friends who’d come from other places, Ann believed Little Cranberry could be repopulated.

  Now, Ann thought to herself, all we need are some young women.

  The friendly competition among the young lobstermen didn’t stop at catching lobsters. By the mid-1970s Little Cranberry’s year-round population included twenty or so bachelors but only a couple of eligible females. Four generations earlier, three Fernald brothers had migrated to the island in search of women. The Fernald brothers might now have to abandon Little Cranberry to find mates.

  Jack had to wonder whether lobstering with the Fernalds wouldn’t put an end to his love life altogether. One day he was lobstering with Bruce. Bruce threw a trap overboard and the buoy jammed in the hauler pulley. When it slipped free it shot like a bullet into Jack’s groin. Jack crumpled to his knees with tears in his eyes. Bruce was relieved when Jack showed no signs of permanent damage, though of course Jack’s recovery did little to ease the competition for females.

  When summer arrived on Little Cranberry the warm weather brought a rush of shedders for the lobstermen to catch but also a rush of vacationers to the island. Jack and the Fernald boys worked hard, and they partied hard. A keg on the beach would entice the summer girls from their parents’ cottages. In the light of a campfire the young women would contemplate which of the young lobstermen outdid the others in earthy charm and rugged good looks.