Recent Work By Dr. Ellen Prager

Reprinted with permission from Sex, Drugs, and Sea Slime: The Oceans’ Oddest Creatures and Why They Matter, by Ellen Prager, published by the University of Chicago Press. © 2011 Ellen Prager. All rights reserved.

Chapter 2:  Mega-Slime, Seduction, and Shape-Shifting

Within the citizenry of the sea, there are some organisms whose dull or familiar countenance hides a secret and strange way of life. Such is the case for an eel-like fish with ancient origins, a well-known and highly delectable crustacean, and an organism with impressive powers of regeneration that masquerades as an undersea log. The talent among these three marine creatures the hagfish, lobster, and sea cucumber  is impressive. The hagfish can produce an inordinate amount of slime and tie itself into a knot. The lobster is equipped with supersoaking blasters that it uses to wield a powerful potion; and when under attack, the sea cucumber has defenses that are the envy of science fiction writers. These three organisms are definitely among the oceans’ most fascinating and surprising of residents.

The Hagfish

To know a hagfish, is to love a hagfishor maybe not. A good friend of mine in Maine ( you know who you are) has developed a new type of phobia; she is convinced that upon entering the Gulf of Maine for a leisurely swim, she will be the target of hagfish. I have tried to convince her that as long as she is not dead or nearly so, they should not be a problem, but she remains unconvincedhagfish have become her worst nightmare and with good reason.

Hagfishes are blind, jawless, scaleless, and finless fishes with a relatively flexible cartilaginous skeleton somewhat like that of sharks and rays. They resemble eels with a flattened oar-like tail, thick, slippery skin, and one singular nostril above their mouths, around which are several stubby, barbed tentacles. Interestingly, they also have four small hearts.

An adult is typically about half a meter (18 inches) long, though they have been known to reach a scary size of 1.4 meters (4.6 feet). Hagfishes live throughout the world’s oceans at the bottom, where it is relatively cool. A few species inhabit shallow waters, but most are found deeper, down to at least 5,000 meters (16,400 feet). It is estimated that there are hundreds of thousands of hagfish residing in the deep waters of the Gulf of Maine.

Though jawless, the hagfish is not without teeth or a means to gain access to tender flesh. It has an extendable tongue equipped with two curved rows of sharp, horny teeth that open and close like a book. Just above that, the hagfish has a fang, which is used to snag prey and keep it from wriggling away. Its toothy tongue and hooked grasp are effective for feeding on soft-bodied creatures, such as worms and other small invertebrates, but not so handy when it comes to prey with tougher skin or scales. Hagfishes have, however, discovered another, easier way to gain access to their victims’ tasty, tender insides. They go in through open orifices, such as the mouth, gills, or yes, I am sorry to say, the backdoor. Once inside their prey (already or mostly dead, I swear), hagfishes feast on soft flesh, muscles, organs, and guts. Fishermen know this sly tactic all too well because sometimes upon hauling in their catch all they get is a fish-skin bag full of bones and squirming hagfish.

Along with their gruesome propensity to feed on the dead, hagfishes are well known for their slime, lots of slime (plate 2). If a hagfish, alias slime monster or slime hag, is threatened or injured, it releases mucus from hundreds of glands along its body. In just minutes, one hagfish can fill seven buckets with slime. The glands of the hagfish actually release a thick white fluid containing vesicles of mucus and bundles of thread-like cells. Like balls of string uncoiling, the threads unwrap; they then tangle, combine with the mucus, absorb seawater, and expand into massive amounts of sticky, slimy hagfish goo. Hagfishes use their slime to deter predators and facilitate escape.

However, if a hagfish gets caught in its own slime, it can suffocate and endure a most unpleasant fate—death by goo. It has thus evolved a few useful tricks to clear away its own slime. When slime gets up its nose, the hagfish blows it out by sneezing. To free its body of slime, the hagfish wraps its tail around its body and then slides the knot toward its head, scraping itself clear of goo. Its excellent knot-tying skills are also used in feeding to create leverage and improve its flesh-tearing abilities. The hagfish bites onto an irregularity in the skin of its prey and then slides a knot up toward its head, thus enhancing the strength of its pull and ripping power. This process, however, is slow and awkward, so going for the orifices is still a quicker and more efficient means to obtain access to a victim’s soft, tasty insides.

Hagfishes spend most of their time at rest hidden within burrows or among rocks at the seafloor. They can also go for long periods of time without feeding. Following the 1989 Loma Prieta earthquake, hagfish at the Moss Landing Marine Lab survived for fourteen weeks without food. They are quick to respond, however, when a meal is at hand and will converge en masse should a bounty of carrion become available at the seafloor, such as a dead whale. Scientists investigating baited traps in the deep sea regularly find them teeming with feeding, writhing hagfish. The hagfishes have excellent olfactory and tactile senses; they readily sniff for and feel out the weak or the dead. Not much to worry about on a leisurely swim, but for me at least, burial at sea is no longer an option. And as for my friend in Maine, she continues to spread the word about the ghoulish hagfish. One of her disciples is a triathlete who competes during the summers in New England when the water is relatively balmy. He regularly dons a wetsuit to ward off not so much the cold, but rather the sneaky hagfish. On a more positive note he says that just knowing that the orifice-seeking creatures are out there makes him swim faster.

Amazingly, there are some organisms in the sea that find hagfishes appetizingcod and sharks, as well as octopuses, seals, and dolphins make slippery meals of these not-so-lovely fishes. Hagfishes have changed little over the last 330 million years and are thought to be one of the early ancestors of vertebrate animals with a braincase, such as humans. If you thought evolution from primates was hard to swallow, how about having a hagfish in your ancestral lineage?

Love Potion # 9

They have been called the cockroaches of the sea, were considered junk food by America’s early settlers, and are now the ultimate in fine dining. But rarely are lobsters recognized for the power of their pee, their antisocial behavior, or the growing pains they must regularly endure. Over decades of laboratory and field research, scientists have discovered many fascinating, and in some cases rather bizarre, things about lobsters. And a warning if you choose to read on: the lobster on your plate may never look quite the same or quite as delectable.

There are over one hundred species of lobsters found throughout the world’s oceans, including the classic large-clawed American lobster, better known as the Maine lobster. There are also spiny, mud, spear, whip, and the shovel-like slipper varieties. Their hues vary, from the typical greenish-brown to tan or red, to almost a bluish color. Due to rare mutations, the well-known Maine lobster can sometimes be found suited in bright blue, white, or an odd half-and-half coloration. The basic body plan of a lobster goes something like thisan external hard shell or carapace, a head that is fused with the upper torso, two stalked, moveable and compound eyes, a tail fin, and ten legs. What chefs and diners usually call the tail is actually the animal’s muscle-laden, segmented abdomen. The lobster’s firm abs are well toned from use in fast swimming escapes, as anyone who has tried to catch one knows. They use rapid contractions of their abdominal muscles to flap their tails and sprint away backward. At one time, scientists thought that lobsters were mainly scavengers, but now they are believed to be active foragers, and at times, ambush predators. They use their claws, jaws, and legs for crushing, seizing, slicing, and a bit of dicing. On the menu for lobsters are mollusks, such as mussels, clams, and scallops, as well as sea urchins, worms, and crabs. Some lobsters have also been seen to eat fish or filter feed, straining seawater for coarse particulate material. If dead fish are available, they will eat that too, and they sometimes even eat each other. In fact, lobsters have been known to ingest a lot of things, including pieces of plastic, tea bags, wool, and even a rusty nail. In general, however, adult lobsters seem to have a discriminating palate, with a preference for fresh shellfish, crabs, or sea urchins.

Most lobsters, particularly in relatively shallow water, are night owls, nocturnal foragers. Shortly after sunset they leave the protection of their dens to go on the prowl. When they return, often just before sunrise, they may go into the shelter they left from or seek out the closest available place for protection. For the Caribbean spiny lobster, a good hiding hole is best if it also comes with company. It looks for crevices, overhangs, or coral outcroppings that can provide concealment and protection, and that contain other spiny lobsters. More is better when it comes to warding off predators such as sharks or a grouper, as a wall of waving whip-like spines covered with tiny spikes must deter many a hungry invader. A backdoor for escapes is also handy, and many lobster holes have two entrances or exits. The adult Maine lobster, on the other hand, does not seem so fond of its neighbors and will fight fiercely over dominance and the best shelters.

Of course, for these lobsters the best dens are not just good for protection, they also lead to more mates, more sex, and probably more descendants.

What determines a winner in the power struggles of the Maine lobster? In this case, size does matterclaw size that is.

Research suggests that the Maine lobster is typically a combatant, promiscuous creature. Undersea battles establish a hierarchy that allows dominant males to get prime real estate and use it to attract the most mates. Posturing and displays resolve some confrontations, while others end up in a brawl, a boxing match, or a brutal fight to the death. Some lobsters choose to avoid opponents all together and will run away from a fight or make a fast retreat with a few flicks of the tail. Lobsters that do decide to engage begin by sizing each other up, whipping their antennae to and fro to feel and sniff out their opponents. They may then push, shove, and lock claw to claw, in an arm-wrestling test of strength. In battle, sometimes it is the lobster that draws a claw first that wins, like a western-style duel, or they may test each other’s nerve with a game of “chicken.” In the extreme, claws or other appendages may be torn or ripped from their bodies.

Luckily, lobsters can regenerate most of their appendages. If an eye is lost, however, they cannot grow it back, and strangely enough another appendage may grow in its place, such as an oddly located walking leg. And if the need should arise, a lobster can jettison or slice off its own limb, a clever escape tactic, especially if you can grow back the lost appendage. In large tanks, some victorious lobsters have been observed to show mercy on the defeated, while others are not so kind and may mutilate or hack the loser to death. Research has also revealed that in fights, lobsters get really pissed offliterally.

Whether it is as a precursor to battle or in a bit of foreplay, when Maine lobsters meet, pee matters. They are well-equipped and stocked to make good use of their urine. Each lobster has a pair of muscular nozzles located just below its antennaea twin set of built-in pee-blasters, which are connected to an ample supply of urine that is stored in two bladders also located within its head. To further its pee-shooting range, a lobster can generate water currents with its gills and mouthparts, enabling it to reach a target, such as an opponent’s face, some seven body-lengths or about 1.5 meters (5 feet) away. Lobsters actively sniff for undersea “odors” or chemicals by flicking their smaller pair of antennae, or antennules, back and forth. In laboratory studies, the lobster to pee first and with the “sweetest” smelling urine, along with the largest claw, is the most likely to win in battle. Underlying the effects of the lobster’s urine are hormones that seem to control aggression and additional chemicals or pheromones that act as this leggy crustacean’s version of “Love Potion #9.”

When a female Maine lobster approaches a shelter, hot for some action, she not only sniffs for a male’s pee, she lets loose a stream of her own. Her urine can render a once brutish male docile and even touchy, feely. Instead of smacking the female over the head with his crushing claw, the seduced male waves his antennae gently over her body as she enters his den. On occasion, a female’s love potion may not be fully effective and she may be rejected, especially if she is unprepared to come out of her shelland not in a metaphorical sense. Before mating, a female lobster molts, whereby she becomes soft, vulnerable, and her relevant private parts are accessible to the male. By doing so, she also conveniently provides her mate with a nutritious postcoital snack, her molted shell. After mating, a female lobster may spend a few days recovering from her molt within the male’s shelter. She then simply walks away and a new female lobster will come to call.

Dominant males are repeatedly seduced into a continuous series of short-term affairs, while the females seem to choose when and with whom they will mate. The subordinate males, those that do not win battles or get the best lairs, will sometimes get a few of the dominant males’ leftovers, but without a large, attractive condo to share, they remain mainly frustrated bachelors on the make.

Female lobsters can store the males’ sperm for up to about three years, using it to fertilize several batches of eggs. They may carry tens of thousands of eggs glued under their abdomens for some ten months before hatching occurs. In their larval stages, the young lobsters join the ranks of the plankton for days, weeks or possibly months depending on the species and surrounding conditions. Each baby lobster will go through several developmental stages before growing into its more familiar form and taking to a life at the seafloor. Juvenile lobsters tend to live in shallow, protected coastal habitats until they are large enough to safely roam at greater depths.

For lobsters, molting is an important part of mating, a life-long necessity, and conceptually at least, a painful process. Like other crustaceans, as a lobster grows it must molt to replace its rigid carapace with one that is larger and able to hold a bigger body, sort of like turning in a small compact car for a minivan. Mature lobsters may molt several times a year; juveniles must do it more often because they grow faster than the adults. But they don’t simply leap out of one shell and grow another; it is a lengthy, fascinating process, and lobsters spend a good part of their lives undergoing the changes involved. Molting begins with some serious dieting, as a lobster must shed some of its mass. Simultaneously, a new paper-thin exoskeleton starts to form under its shell and its blood is moved from its outer appendages, like the claws, spines, or legs, into its body. Then it is time for a drink, a really big drink. A lobster guzzles water so that its body swells and its old carapace is pushed apart. Essentially, some serious bloating causes the lobster to unzip, unhinge, and literally burst at its seams. Lying on its side, slicked up with some lubricating slime, a lobster then must pull its body, including the antennae, legs, spines, claws, and mouthparts, out from the remains of its old shell. For Maine lobsters, particularly those well endowed in the claw area, the process must be especially difficult and possibly painful. They must pull their large, bloated claws through the slender jointed wrists of the old carapace. Think of trying to squeeze swollen hands through a pair of handcuffsand they have to do it every time they molt. Once its appendages are through and the last bit of its shell has been shaken off, the newly emerged lobster or “shedder” is a floppy, jellylike creature trying to stand up on wobbly legs with a shell the consistency of thin, wrinkly plastic wrap. It then goes again for the bloat; drinking water to inflate its size even further so that it has room to grow within its new carapace once it has hardened. A lobster typically devours some of its old shell for a megadose of minerals and nutrients.

Shedding can take just several minutes or last for up to half an hour. It is a dangerous time for the lobsters, as they are immobile and defenseless. They may go into seclusion for several days, emerging only after their new shells have begun to harden. The first body parts to stiffen are those most critical to foraging, such as the tips of the walking legs and mouthparts. It can take several months for the lobsters’ carapace to harden completely.

Maine lobsters molt principally in the relatively warm summer months. The Caribbean spiny lobster may not have the brutal mêlées or social rankings of the Maine lobster, but they exhibit at least two very curious and unique behaviors. Just after the first autumn storm, in locations such as the Bahamas, Florida, Cuba, the Gulf of Mexico, and Central America, spiny lobsters begin a two-to-three-week trek into deeper, offshore waters.

Many marine organisms make lengthy migrations, some much longer than that of the spiny lobster, but few others do it with such style. During their fall trek, thousands of lobsters will traverse the open bottom, marching in an amazing single-file formation known as a queue. They line up head to tail, each lobster closely following the one in front, guided by the touch of its antennae. The movement of the lobsters seems to entice others to leave their shelters and join the crustacean train. Scientists think that a queue is formed to reduce drag, like a professional bicyclist drafting behind the racer ahead. It may also help to prevent predation or aid in orientation while marching.

The spiny lobsters are thought to venture into deeper water to avoid the relatively cold temperatures brought on by storms in the fall and winter months. Other lobsters are known to migrate seasonally, between shelters and habitats, but the spiny lobster may be the only one that creates a single-file offshore express. Experiments suggest that lobsters use the Earth’s magnetic field as a guide to navigate the open ocean and that chemical signals may lead them to specific home ranges or locations.

The spiny lobster’s acute sense of smell also appears to provide it withan exceptional medical diagnostic capability; one that doctors can only dream of. Mark Butler, a professor at Old Dominion University, and Donald Behringer, a research scientist at the University of Florida, discovered that juvenile spiny lobsters will actively shun diseased neighbors. This normally social lobster will avoid dens that harbor lobsters that are infected with a lethal, pathogenic disease, essentially placing them in quarantine.

Even more startling is that the juvenile spiny lobsters seem to be able to detect or “smell” the disease before it becomes infectious. Butler suggests that their behavioral change is an adaptation to thwart the spread of a lethal disease, and that it may be the only known example of this sort of “shunning” in the animal kingdom.

Even with their crushing claws, spiny swords, shield-like carapace, and of course, Super Soaker pee blasters, lobsters are not invulnerable to predators. A wide range of creatures find lobsters fine dining, including fishes, sharks, sea turtles, octopuses, and of course, the most feared of allhumans. For those of you who like to eat the disgusting gooey green stuff inside a lobster’s body, the tomalley, it is the liver and pancreas combined, which acts as a filter and can accumulate pollutants or toxins over time. It is probably best to forgo this rather questionable delicacy.


Reprinted with permission from Sex, Drugs, and Sea Slime: The Oceans’ Oddest Creatures and Why They Matter, by Ellen Prager, published by the University of Chicago Press. © 2011 Ellen Prager. All rights reserved.

How did the title come about?

One of my favorite descriptors of the book by a reviewer is “tastefully scandalous”!  The original title was Weird and Wild Under the Sea: And Why These Creatures Matter.  However, as I delved into the academic literature and talked with colleagues, a few rather intriguing and shall we say, titillating, themes evolved.  Turns out that in the ocean more creatures use, have, or are made up of slime than I ever realized—it is a seriously slimy place beneath the waves.  I also discovered all sorts of wacky reproductive behaviors in the ocean.  And while I was aware of some of the research being done by my colleagues in the field of biomedical research, I never knew the breadth and diversity of organisms being studied in the search for new drugs or that are being used as models to study disease.  And so the title, Sex, Drugs, and Sea Slime: The Oceans’ Oddest Creatures and Why They Matter was born. It did take a little convincing to get my publisher to go along with it. And while I really like the title and think it is absolutely appropriate, I hope that people will not shy away from the book because of it or think that I did it simply for shock value.


What was the inspiration for the book?

There were several “light-bulb goes on” moments on this one, beginning with a conference in Washington, DC on biodiversity loss. It is a very significant topic, but I came away thinking that nobody outside the scientific and conservation communities represented at the meeting would ever understand what biodiversity in the ocean is or why the heck they should care. Too much science-speak and jargon with little relevance to the average person. I began to ponder how to make ocean biodiversity an interesting and relevant topic for the layperson.

Then, while visiting a wonderfully funny friend in Maine, I discovered the answer (I hope).  She had me laughing almost to tears with her newly discovered, little-known, ocean phobia—hagfish.  There are hundreds of thousands of hagfish in the deep waters of the Gulf of Maine.  They are jawless, finless, eel-like fish that have only small teeth on their tongue.  They cannot tear through the scales or tough skin of their prey. To feed on the tasty inside flesh and organs of fish and other victims (I mean prey), they must therefore find other means of access—in through the mouth, gills, or you might say, the “backdoor”.  With so many of these orifice-seeking ghoulish creatures in the Gulf of Maine, my friend (crossing her legs) explained that swimming just wasn’t so appealing anymore. Actually she was joking–they feed mostly on the dead or dying, so a quick dip isn’t really a problem.  Burial-at-sea, now that is another story, unless you want to share your remains with writhing, squiggly hagfish! When I heard that Osama Bin Laden had been buried at sea, I tweeted that even the hagfish were unhappy!  They are also called slime monsters or slime hags because they can create large quantities of gooey hagfish slime in just minutes (a defense mechanism).

I am proud to say that the slimy, orifice-seeking hagfish was an inspiration.  Using weird, wacky, and, okay, totally disgusting, biology stories would be a great way to hook readers and engage them in learning about the great diversity of life in the ocean and how it is connected to the average person’s life.  Yes, there are even reasons why you should care about the hagfish!


Do you have a favorite story or creature from the book?

Lots of them.  One is not only a fun story, but exemplifies how I came by much of the information included in the text.  I sent an email to Dr. Al Stoner, a colleague that has long been studying queen conch, and asked if he had any fun biology facts about the queen conch.  And in an email he replied, “There is a real advantage to studying the reproductive biology of an animal that is big, slow, mates for hours on end, and has a penis half its total body length”. As you might imagine, my eyes lit up with joy and I dove into the literature to learn more. I found clever and funny limericks about the well-endowed male queen conch and an even more surprising fact.  When the male queen conch extends his “verge” (that’s what the scientists call it) out of his large shell, around, and under the female, it is vulnerable to hungry crabs and eels (sorry, men).  But not to worry, lose one and they just grow another! The male queen conch can regenerate its penis!


What do you hope people come away with after reading the book?

One of my main goals with this book was to make science entertaining, understandable, and relevant to the average person. So I hope people learn, but have great fun doing it. Of course, I also want people to better comprehend the great importance of the diversity of life in the ocean not only for the ocean, but for humankind as well., in terms of the things we all care about, such as jobs, food, health, the economy, security, and our quality of life.  For readers to also become better stewards of and have a stronger voice for the oceans, and to promote more sustainable use of its resources. It is meant to be entertaining, but with a more serious and relevant underlying message.


What are some of your favorite personal ocean adventures?

I have been incredibly fortunate to have so many wonderful, sometimes a bit wild, ocean adventures and jobs so far.  During the summer following my junior year in college, I worked as a safety/support diver for an undersea laboratory in St. Croix, U.S.V.I.  My job title was really a euphemism for undersea slave and all around underwater gopher.  But it was fantastic and I learned a ton about diving, marine science, and doing fieldwork.

I taught oceanography to undergraduates out at sea for six weeks aboard tall sailing ships for Sea Education Association.  A wonderful and exciting program, thank goodness I do not get seasick.  My very first cruise we went through a hurricane in the open North Atlantic (was there something about that in the fine print of my contract?). I was also at one time the director of a marine laboratory on a very, very small island in a remote area of the Bahamas.  It was a difficult job, things were always breaking down, and people tended to go a little nuts being so isolated.  And we had to worry about hurricanes, drug-runners, and a serious lack of supplies. Not so fun, but the snorkeling, diving, and hiking off-hours were fantastic.

I have also lived underwater for almost two weeks, twice, in the Aquarius Reef Base habitat in the Florida Keys.  The habitat is in about 60 feet of water in a sandy area on Conch Reef some 3.5 miles off Key Largo.  Living in the habitat allows divers six to nine hours of diving each day down to about 100 feet. It was fantastic. You truly feel a part of the underwater world instead of just a short-term visitor. Every day we would swim to our work sites on SCUBA and see the same corals or sponges, with resident fish and even a big green moray eel. Essentially, we got to know the neighborhood. And even just watching from the habitat viewport while we were inside was amazing.

Lastly, I have to say that I especially appreciate the time I have spent and am spending in the Galapagos Islands. I did research there in the 1980s and have been the science advisor for Celebrity Xpedition in the Galapagos for several years now and get to go there several times a year. The Galapagos allows us to view what our world must have been like before humans decimated the planet’s wildlife and destroyed habitats. The animals have no fear of humans, are extremely well protected, and you can see extraordinary behaviors and wildlife right at your feet. It is a place everyone should go at least once in their lives,, one that inspires an entirely new and heightened appreciation for the wilds of our planet.


What’s next?

I’m doing a lot of public speaking right now and between the reactions I’m getting from the book and at my talks, it seems that I am able to engage broad audiences, keep them interested, and make them laugh (even with science).  That last part is a bit addictive and I can see why comedians like their jobs.

I love the idea of marrying science and the environment with entertainment, and I think I am pretty good at it.  So I’d like to do more in that vein, use my ability to make people laugh and relate to broader audiences to better communicate ocean and earth science to the public through entertainment.  Know anyone in the entertainment industry?

Having made all the mistakes that may be possible when appearing as an expert on television, I am now very comfortable in front of the camera and would maybe like to do more of that as well.  I’ve also started writing an ocean-related fiction book for young readers, but it’s really a new genre for me, so I’ll have to get an agent and face potential manuscript rejections like all the writers out there.

It’s exciting not knowing what is next, and yet somewhat terrifying as well – that “paying-bills” thing always gets in the way!


Dr. Prager will be on a public speaking tour associated with Sex, Drugs and Sea Slime: The Oceans’ Oddest Creatures and Why They Matter sponsored by Microsoft Research.

October 12th, Harbor Branch Oceanographic Institution, Ft. Pierce, FL
October 18th, University of South Florida, St. Petersburg, FL
October 27th, Louisiana State University, Baton Rouge, LA
November 2nd, Rookery Bay Reserve, Naples, FL
November 19, Miami Book Fair, Miami, FL
December 5th, Oregon Museum of Science and Industry