Habitat: subtidal to edge of continental shelf, in any sheltered spot
Lobsters differ from shrimps in having three pairs of clawed legs, the first with very large claws. Southern "Spiny Lobsters" are only distantly related; freshwater crayfish are closer. Lobsters, or "Bugs", are mainly nocturnal, and feed primarily on living or freshly killed food rather than scavenging on carrion, as was once thought. Although they are predominantly solitary creatures, lobsters do have a sort of social life amongst themselves. Males are more aggressive than females and will form pecking orders among individuals in an area. Female lobsters apparently seek the protection of a male when molting, then mate afterwards. Lobsters shed their shells once or twice a year, depending mainly on the temperature.
Inshore lobsters tend to stay in one place, seldom moving more than a mile or so, but deepwater lobsters farther out on the continental shelf follow a seasonal migratory pattern: shoreward in summer, returning to the shelf again in the autumn. The record travel so far is 225 miles covered by a lobster tagged off the continental shelf and recovered at Port Jefferson, Long Island, New York.
Female lobsters carry their eggs underneath their tails for much of the year. Animals like this are known as "in-berry", and must be released immediately. A one pound lobster is estimated to be 5-7 years old. Most lobsters seem to be lefties - that is, the big crusher claw is on the left, and the smaller ripper claw is on the right. But just like people, this is not 100%, and occasionally you may run across a right-handed bug. The crusher claw is much stronger than the ripper.
Lobster anatomy ( actually, it's a crayfish, but they are very similar. )
Up close and personal
CRUSTACEANS FOUND TO HAVE SHELLACIOUS APPETITE
By Richard Degener, Staff Writer
Press of Atlantic City, August 11, 2004
Lower Township - Bill Figley wasn't sure what he would find in the stomach of a New Jersey lobster. When he found out, he was stumped. Figley, a marine biologist with the state Division of Fish and Wildlife, discovered lobsters like to dine on the same thing that sends shore vacationers flocking to the best seafood restaurants. For breakfast, lunch and dinner, lobsters prefer lobsters.
The study of the eating habits of lobsters found that 18 percent of a lobster diet is other lobsters. When they aren't eating each other, they are looking for other crustaceans, such as crabs. Together, lobsters and crabs make up 58.8 percent of what a New Jersey lobster eats. "We knew they were cannibals, but didn't realize it would be that high. I can't explain why it's so high, " Figley said.
Bergen County resident Thomas Brady, while shopping for fresh lobster Tuesday afternoon at the Lobster House on Schellenger's Landing, presented one possible theory. "They have good taste. If they eat lobster, it must be good, " Brady said. And if they eat lobster, could that be why they taste like lobster? "You are what you eat, so that's why lobsters taste like lobsters, " said Figley. There's no science behind it, but it sounds logical enough. Maybe seafood restaurants should advertise their lobster-fed lobsters.
Lobster House owner Keith Laudeman, who sells more than a half-million pounds of lobsters per year, said the theory sounds plausible. It isn't just the lobsters, but the fact that the diet of lobsters in general is prime seafood, such as clams, crabs, and mussels. "Lobsters taste so good because the eat shellfish, " Laudeman theorized. He also said they have tried to eat his workers at the restaurant. That's one reason they use rubber bands to secure the claws. Another reason is something seafood restaurants have known for years but scientists are just figuring out. Given a chance, they dine on each other right in the lobster tanks.
"They eat each other like there's no tomorrow. Even with the bands, they get in their with their little pincers, " said John Oney, an assistant manager at the Lobster House seafood market. The news that lobsters eat lobsters didn't seem to hurt business at the Lobster House. Most customers seemed intrigued. "It's interesting. Cannibalism, " said Richard Oswald of Chesilhurst in Camden County. "That makes them better, " said his wife, Dana.
Figley figures it is mostly a matter of size. Lobsters hang out together and some are larger than others. All are very susceptible when they molt and lose their hard shell. "It's a matter of, 'I'm bigger than you and I'm going to eat you, '" Figley said. He does not believe the study is an anomaly, because lobsters were collected for several years at artificial-reef sites off the Atlantic and Ocean county coasts. The state collected 98 adult lobsters and sent them to the National Marine Fisheries Service laboratory at Sandy Hook for analysis.
Lobsters tear everything up as they eat, so it took a while to determine exactly what was in their stomachs. "A lobster mouth is like a blender. It was a bit of a detective game, " said Frank Steimle, a biologist at the Sandy Hook lab. The first dilemma was figuring out why their stomachs contained what appeared to be bits of black plastic. It went on the data sheets as "mystery black particles" until it was discovered to be the black cases that hold skate eggs. They make up as much as 12 percent of the lobster diet.
Steimle sorted through a plethora of worms, rock crabs, sea horses, starfish, and various crustaceans, bivalves, gastropods, hydroids and fish. He was happy he did not find the human hair and cloth fibers he discovered in lobsters when sewage sludge was dumped off the coast almost two decades ago. The dumping stopped off Sandy Hook in 1986, and now the lobsters appear to be back on their normal diet. They're dining out and eating only the best: A lobster dinner at the New Jersey shore.
A modern wire
lobster trap - a common sight around shipwrecks
figures in red are illegal to take
Calculated weight estimates of male, female, and sex unknown lobsters ranging in carapace length from 3-3/8 to 5-1/2 inches, by one-sixteenth inch length increments. Estimated weights are based on length-weight formula conversion constants provided by NMFS, 1993.
Female lobster with egg mass
The Long Island Sound Lobster Blight / Shell Disease
There appear to be not one, but two causes for large die-offs of lobsters and other shellfish in Long Island Sound and surrounding waters. One appears to be an internal protozoan parasite, and the other a bacterial disease of the shell. The protozoan disease seems to be confined as yet to Long Island Sound, where it has essentially wiped out the lobster population. Affected individuals show swelling in the mid-body, and many die soon after capture. The exact cause of the plague has not been isolated.
The shell disease is more widespread. Shell disease is more prevalent on larger, older lobsters, which molt less often. The resulting black pockmarks and scars on the claws and body are evident in the photo at right, and also at the bottom of this page. In especially bad cases, the shell may be eroded completely through, exposing the soft tissue beneath. Victims are often lethargic and slow, although the disease is thought generally not to be fatal. Shell disease is not supposed to affect the taste of the lobster, but the only affected one that I ever ate didn't taste very good, and I don't bother catching sick ones any more.
Events like this are not unknown, having occurred off Canada, Maine and New England in the past. Neither of these diseases appears to be dangerous to humans, but the decline of the lobster population and the reduced marketability of the remaining catch will probably affect the industry for years to come.
Explaining the Long Island Sound Lobster Die-off:
The Perfect Storm
August 1999 was unusual for commercial lobster fishers in Long Island Sound (LIS). Catches were unexpectedly dropping and large numbers of dead lobsters were being pulled up in the western part of the Sound. Dead lobsters were not limited to adults but also included sub-legals, molting lobsters and berried (females bearing eggs) lobsters.
The situation did not improve in September. There was almost no fall run or fall molts in parts of the Sound. Hard shell lobsters were weak and lethargic with many lobsters dying within hours of being landed. Overall mortality increased and landings declined.
The situation worsened in October 1999 as the die-off spread to other organisms including blue crabs, rock crabs, spider crabs, sea urchins and starfish. Wholesalers reported high mortality of lobsters within days of receipt. Landings continued to be lower than normal and lobster fishers also found berried lobsters molting, an unusual situation.
The die-off in western LIS had a significant economic and ecological effect on the lobster resource. Landings decreased anywhere from 64-99% in the western part of LIS Approximately 70% of the lobster fishers surveyed by the Connecticut Department of Environmental Protection (CTDEP) in western Long Island Sound lost 100% of their total income and the remainder lost 30% to 90% of their total income. The die-off continued into 2000 raising concern about the ability of the population to rebound. Surveys since 1999 have found low abundances of females and low numbers of larvae.
Lobsters are cold-blooded animals with an extreme sensitivity to environmental conditions that can alter their metabolism. LIS is the southern end of the commercial fishery of American lobsters and is near the limit of their inshore range (Factor and Clemetson 2003). Summer water temperatures in LIS can reach the upper margin of lobsters? tolerance limits, about 68? F. Lobsters can withstand higher temperatures, up to 35? C (95? F), however, when water temperatures go above 68? F, lobsters respiration rate increases and the animal can become physiologically stressed.
Hypoxia (low dissolved oxygen) in the water column can also stress lobsters. Hypoxia often coincides with higher temperatures when lobsters need the most oxygen to maintain equilibrium. These conditions can lead to death, disruption of hormone systems and reduced immunity to pathogens.
The Perfect Storm
Scientists identified four possible factors that contributed to the die-off: changes in water quality condition s including elevated temperatures and changes in dissolved oxygen levels; changes in environmental conditions such as pesticide levels or changes from storms; lobster crowding; and diseases.
In June 2001, Congress earmarked special funds for research on the lobster die-off. Over $3.5 million in federal and state of Connecticut research grants were awarded to 17 science research teams to investigate the causes behind the die-off. In October 2004, after three years of research, scientists summarized their results at the 4th Annual Lobster Health Symposium.
Scientists believe that a series of environmental factors and events combined to create habitat conditions leading to the die-off of lobsters in western LIS. Warmer water temperatures, low oxygen levels, overcrowding and disease collectively contributed to the die-off of lobsters. Physical & Chemical Conditions Hypoxia, temperature and rainfall all contributed to the die-off by making the lobsters physiologically stressed and more vulnerable to pathogens and chemical stressors. Increases in population densities and changes in land use patterns have resulted in increases in nitrogen and silica, both indicators of eutrophication. Increasing air and water temperatures caused a decrease in the renewal of oxygen in the water leading to hypoxic conditions. Sediment samples confirm LIS waters were severely hypoxic just prior to the 1999 die-off.
Surface and bottom temperatures were higher than normal during the summer and fall of 1999. Lack of rainfall led to a highly stratified water column with slow estuarine circulation. Stratification was reduced by a strong mixing event, Hurricane Dennis, which stirred up a cold front and winds, causing the temperature at the bottom of LIS to rise by more than 2? C in six hours.
Tropical Storm Floyd then dropped three inches of rain and caused heavy runoff from surrounding areas, leading to restratification of the water column and continued above-average water temperatures. Scientists conclude that the environmental conditions (higher water temperatures and low dissolved oxygen) present in the summer and fall of 1999 alone were enough to cause high lobster mortalities. The inability of the already stressed lobsters to tolerate the additional change in water temperature may have compounded the problem by inhibiting immune response.
Physiological (Immune & Endocrine) Responses Study
Lobsters show reduced immune function and disruption of hormone systems, such as the molting hormone, in late summer when water temperatures increase. In 1999, higher temperatures combined with hypoxic conditions left lobsters unable to physiologically cope with the changes in the environment and often led to death.
Some lobsters caught in 1999 were infected with the disease paramoebiasis. Amoebae were found in the nervous, glandular and connective tissues of the lobsters. Scientists think that record high lobster densities combined with higher water temperatures and hypoxic conditions promoted infection of lobsters with paramoebae. Long-term monitoring data suggest that increased bottom water temperatures also contributed significantly to the spread of disease.
Shell disease was known to cause death in lobsters in previous years but nowhere near the level of the die-off. Lobsters can generally respond to and fight shell disease but when the carapace is breached or ulcerated by the pathogen, internal lesions can lead to death. In normal environmental conditions, shell disease is not thought to cause mass lobster mortalities. Stressful environmental conditions, however, can make lobsters more susceptible to death from shell disease. Recent research by the Long Island Sound Lobster Initiative shows that few lobsters actually die from shell disease and it was not a major factor in the die-off. The disease still remains a priority in lobster research as it can compromise lobster health and marketability and is spreading to Rhode Island and Massachusetts.
In summer 2002, another lobster die-off occurred in the LIS Central Basin, although on a much smaller scale than the 1999 die-off. Scientists identified a new metabolic disease called calcinosis that may have contributed to lobster mortality. Calcinosis is an accumulation of calcium in lobster tissue, which in advanced stages affects the gills and causes the animals to suffocate.
Characteristics of a lobster suffering from calcinosis include an orange belly and rusty gills covered with abnormal growths. Preliminary results link the deaths in 2002 from calcinosis to a long period of warm bottom water temperature in LIS.
Researchers also explored the possibility that higher levels of pesticides in LIS caused the die-off. Some lobster fishers believed that pesticides used to combat the West Nile virus caused the lobster die-off. Both New York and Connecticut sprayed pesticides in the summer of 1999 t o kill mosquitoes that might carry the West Nile virus. Over 100 lobster fishers filed a class action suit against pesticide manufacturers, contending that the lobsters were exposed to high levels of pesticides washed into LIS after a four-day period of heavy rains from Tropical Storm Floyd. Researchers measured mortality and immune response to three pesticides likely to be found in LIS in larval and juvenile lobsters: methoprene, malathion and resmethrin. Methoprene bioaccumulated in tissues of lobsters but models suggest that the maximum concentration in LIS was well below the threshold for effects in lobsters. The maximum malathion concentrations found in LIS in bottom waters were not within the range of concentrations having effects in lobsters. Studies show that resmethrin has several lethal and sublethal effects in lobsters. Modeling of pesticides levels suggest that maximum concentrations in LIS surface and bottom waters may have had lethal effects on larvae and sublethal immune effects on adults in a few localized embayments. Scientists still need to study the possible impact of the pesticide sumithrin as a stressor in limited areas.
LIS habitat is changing. Periods of hypoxia are now a regular, annual feature in late summer and appear to be lasting longer each year. Scientists warn that the conditions leading up to the die-off in LIS could happen again and could affect other organisms. Clams, oysters and finfish have also experienced mortality incidences but not as significant as the lobster die-off.
In 1994, the Long Island Sound Study (LISS) completed a Comprehensive Conservation and Management Plan that identified seven management issues: (1) hypoxia, (2) toxic contamination, (3) pathogen contamination, (4) floatable debris, (5) living resources and habitat management, (6) land use and development, and (7) public involvement and education.
In 2003, the U.S. Environmental Protection Agency, New York and Connecticut signed the 2003 Long Island Sound Agreement reaffirming the 1994 agreement and identifying specific management goals. Some of the goals include eliminating or reducing hypoxia, reducing bioaccumulation of contaminants in living resources, cleaning up contaminated sites that contribute to pollution and restoring the ecological functions and health of lost and degraded habitats. Agencies involved in managing LIS understand maintenance of the habitat is critical to helping the lobster population rebound.
The Atlantic States Marine Fisheries Commission's (ASMFC) Lobster Health Steering Committee is working to continue research regarding the causes and effects of lobster diseases and for monitoring lobster health over the entire range of the resource. For more information see the NY/CT Sea Grant's Long Island Lobster Initiative web site at http://www.seagrant.sunysb.edu/LILobsters.
NY/CT Sea Grant, ASMFC.
Connecticut Department of Environmental Protection. 2001.
Information Regarding the Impact Of 1999 Lobster Mortalities In Long Island Sound.
Factor, J.R. and A. Clemetson. 2003. Life as a Lobster in Long Island Sound: Biology and Life Cycle.
Lobster Health News Supplement, Joint Publication of the Sea Grant College Programs of Connecticut and New York.
Lobstering for some pointers on catching and cooking lobsters.
Lobster shells are usually a blend of the three primary colors - red, yellow and blue. Those colors mix to form the greenish-brown mottle of most lobsters.
This lobster, though, has no blue in half of its shell. The odds of this kind of mutation occurring are very rare - something like one in 50 million to 100 million. This one was caught in Maine in 2006.
Scientists say blue pigmentation comes from genetic chance, calculated to occur in 1 out of 4 million lobsters. This one was caught off New Jersey in 2003. It now resides at Sea World.
The blue pigment breaks down when a lobster is cooked, turning it bright orange-red, like the one above ( which is not cooked. )
Yellow is perhaps the rarest color morph of all. This one is missing both the red and blue pigments.
The lobster at right was caught off Nova Scotia in 2002. Not only is it precisely half albino, it is also a hermaphrodite - male on one side and female on the other - look closely at the tail.
Lobsters develop independently on each side of the body, which accounts for the two different claws, and also for bizarre patterns like this.
The shell has just split between the tail and the body. The old shell is lifting off, revealing the new one beneath. By now the animal has withdrawn much of the calcium from the old shell and stored it in its blood and tissues. This weakens the old shell in preparation for molting, while allowing the lobster to reclaim precious materials for its new shell.
Although it's not readily apparent, the legs and claws are now pulling out of their casings in the old shell. The tail is still firmly inside, and is the last part to be withdrawn.
The lobster is completely defenseless at this point, and doesn't seem to be making much progress.
Finally, the eyes appear, and the head emerges. The antennae are folded down and still tucked inside their old casings. The legs and claws are all still trapped and hidden from view beneath the old shell. The tail is beginning to break free.
Things are moving much faster now. The entire sequence here covered about 15 minutes.
Most of the tail is now free, as are the legs. The claws begin to emerge, still trapped under the old shell. The antennae are also almost free, folded down between the legs.
In our waters, lobsters typically molt twice a year; in colder waters north of here, just once.
This is the most hazardous time in a lobster's life, and it would not normally molt out in the open where it could be attacked. I watched over this one after exposing it until it could make its own way again.
A flick of the tail now, and the lobster will be free of its old shell. The new shell is soft, leathery, and flexible.
For several minutes the lobster is completely helpless - its legs are so soft and rubbery that it cannot even stand up. The claws are creased and folded.
Initially, the "new" lobster is not noticeably bigger than the "old" one. In the next 15-20 minutes the animal will absorb enough water to inflate the new shell until it is about 30% bigger than the old one, and then re-deposit the stored calcium to harden it. This stiffens the shell and legs to where they are functional again, so that the lobster can walk, swim, and dig, although it will still be soft and vulnerable for several days.
The scenario repeats itself over and over again on a daily basis at restaurants throughout the Garden State. Whether it be boiled, steamed, stuffed or in an au gratin sauce, the North American lobster, Homarus americanus, has been the unwilling guest of honor at more seafood dinner parties than almost any other species of underwater life. Yet few people know how the lobster lives, what it eats, or how it survives in the undersea community. Locally, the clawed crustaceans are found in the shallow waters of inlets such as Shark River, Manasquan and Barnegat and on shipwrecks and rock piles in deeper offshore waters.
The name lobster arouses thoughts of the rocky shores of Maine as the two have become synonymous over the years. For many years, the prime inshore fishery for lobsters has been from southeastern Labrador to southern New England and primarily in the waters of Maine, Nova Scotia, and the southern Gulf of St. Lawrence. In recent times, the inshore fishery has expanded as far south as Cape Hatteras, with sizable quantities of lobsters being harvested in the submarine canyons off the coasts of New Jersey and Long Island. It is reported that in 1956, a 44-pound North American lobster was hauled from the deep water off eastern Long Island.
The claws of the lobster are its prime weapons; the smaller, slender claw is the feeder or shredder claw and the larger, more massive claw is the crusher claw, capable of doing exactly what its name intimates. Despite these formidable weapons, the lobster is vulnerable from the rear. For protection, it resides in holes in rocky jetties or in shipwrecks.
During the daylight hours, lobsters are found in their usual positions, facing the entrance to their lairs with claws at the ready and antennae swaying to and fro like an underwater radar detection system, retreating at the slightest movement. It would be a reasonable assumption that the lobster's large eyes sensed the movement and provoked the quick reaction. The eye of the lobster is very similar to that of a fly. It is compound, made up of thousands of tiny facets or little eyes which are extremely sensitive to light, as evidenced by the lobster's nocturnal roaming habits. Although very sensitive, sight seems to be the lobster's poorest sense. As compensation, Mother Nature has bestowed on the crustacean other sensory devices to alert it to impending danger.
These functions are similar to smell, hearing and touch, and are honed to a high degree of sensitivity. On nearly every part of the lobster's body are tiny hairs that sense movement in the water and transmit the data to the lobster's nervous system, much the same way the human ear senses sound waves in the air stream. This same sensory system is used in orientation and navigation. Hairs on the tips of its legs provide the lobster with information about the terrain it is traversing. In many ways. The lobster operates as a blind person would, feeling its way over and around many irregularities on the ocean bottom. While hearing and touch are recorded by the tiny, bristle-like hairs, the lobster's keenest sense is that of smell. It accomplishes this through tiny chemical receptors on various parts of its body. Remaining down current, the lobster samples the water for scents of enemies or possible food sources and reacts quickly to information. Lobsters even communicate with each other by releasing chemicals into the water.
One of the interesting capabilities of the lobster is its ability to shed a claw at will. This occurs near the second or double joint, where the claw is the smallest. This happens during molting if the lobster has difficulty withdrawing from the claw and also when threatened by an enemy. The rejuvenation process proceeds quickly and within three molts, the claw will have been regenerated to its formidable former self.
The lobster's diet consists of clams, mussels, snails, marine worms, seaweed, starfish and fish when they can be captured. One of the favorite meals of the lobster is the rock crab, Cancer irroratus. This crab is a feisty little fellow who will rear up and defend itself when threatened. This fighting position, although brave, provides the lobster with many flaying appendages to grapple. In contrast, a close relative of the rock crab, the Jonah crab, Cancer borealis, is not favored by the lobster. When threatened, the crab will tuck in its appendages and settle into the bottom, giving the lobster very little to grasp.
It is very difficult to predict the age of a lobster because its growth rate depends on salinity, availability of shelter, frequency of regeneration, water temperature and food - the latter two being the most important factors affecting growth and weight gain. Scientists have estimated that the typical lobster found in a restaurant or seafood store, weighing about 1 to 1 1/2 pounds, is between six and eight years old.
Determining the sex of a lobster is accomplished by turning the crustacean over and looking at the first set of swimmerets on the tail. These appendages are found directly to the rear of the last set of walking legs. On the female, the swimmerets are soft and feathery while the male displays hard and bony projections.
Besides codfish, man is the major predator of lobsters. The current lobster laws in the Northeastern states require that a lobster be at least [ see
regulations ] inches in length from the end of its eye socket to the beginning of the tail before it can be kept. Studies have shown that female lobsters are not ripe for mating until they reach a length of three and three-quarter inches. Harvesting of immature females may be the cause for the decrease in the average size of commercially caught lobsters over the last few decades. More laws are being introduced each year to control the numbers and sizes of lobsters that can be taken.
The North American lobster is an entrenched member of our culinary heritage and must be harvested in a responsible manner in order for our descendants to enjoy this clawed crustacean. Remember that the North American lobster comes from the waters of our own state. When somebody says "that was a wonderful Maine lobster, " smile ... and let them in on our secret.
This article first appeared in New Jersey Outdoors - July / August 1988
I make no claim as to the accuracy, validity, or appropriateness of any information found in this website. I will not be responsible for the consequences of any action that is based upon information found here. Scuba diving is an adventure sport, and as always, you alone are responsible for your own safety and well being.