Dive Dry with Dr. Bill

#355: "Bugs" of a Different "Flavor"

'Tis the season... only a few more shopping days! No, I'm not talking about Christmas, Hanukkah, Ramadan or Kwanza. I'm referring to bug season... and not mosquitos, yellow jackets or sand fleas. We're talking highly edible bugs... lobbies, California spiny lobster or Panulirus interruptus if you prefer. One nanosecond after midnight this Saturday morning, hordes of bug hunters will enter the water as season begins. It is one of the few times I avoid submergence because a number of these divers probably haven't been in the water since the previous season ended. I stopped hunting underwater and on my surface intervals back about 1975. However, I have no problem munching on bugs taken legally by my dive buddies!

There are about 50 species of spiny lobster throughout the world in tropical to temperate waters. The California variety is found from the tip of Baja to at least San Luis Obispo, with one record from Monterey. They inhabit varying depths at different times of the year. During spring when they mate and give birth, they move into shallow waters. Then in the fall they migrate down to deeper depths of as much as 200 feet or more. They also show a diurnal or 24-hour cycle in their behavior, remaining within protected holes and crevices during the day and wandering out at night to feed under the cover of darkness.

Although most think of lobster as bright red, and they are under dive lights and in the steaming pot, they also have beautiful markings in yellow, orange, green and blue. As members of the crustaceans along with crabs, they have a hard exoskeleton or external skeleton and segmented bodies. To grow, a lobster must shed its old exoskeleton, and create a new and larger one through a process known as molting. The exoskeleton splits behind the carapace and the unprotected lobbie slips out, expands to its new size and secretes a new exoskeleton out of calcium carbonate.

Although usually classified as scavengers since they will eat dead animals including fish, lobster also function as "vicious" predators. Their prey is mostly attached or slow-moving critters that are benthic (living on the bottom). Munchables include sponges; snails; clams, mussels and other bivalves; barnacles and sea urchins. They have strong jaws that can crush their food, and I have filmed them eating sea urchins like corn on the cob. Few realize that lobsters are a major factor in keeping purple and red sea urchin populations in check. When they, along with sheephead, are overfished as is the case in many areas on the mainland (and some here on Catalina), sea urchins often dominate and destroy the kelp. Fortunately, both predator populations are healthy in our dive park, so you rarely see red or purple urchins outside the safety of their hiding places.

In turn, lobster are eaten by... humans (hopefully only during season). Native Americans in coastal areas of California also feasted on them. Oh, there are other predators, too, but in many areas we are the dominant threat to this ecologically important species. Fish including kelp bass, sheephead, scorpionfish, moray, cabezon, horn and leopard sharks all share our love of lobster. Even the giant sea bass is said to take bugs, often out of season when they are in the shallows during summer. They do so by suction feeding. Some scientists have suggested they can vacuum them up from out of their hiding spots, but I'm wagering they take them mostly at night out in the open. Invertebrates like octopus and even other lobster will dine on them as well.

The California and other species of spiny lobster lack the defensive and feeding claws of the species found off New England. Instead, they use their antennae as whips to fend off potential fish predators. I've filmed lobster warding off kelp bass, sheephead, garibaldi, morays and lingcod this way. The spines on their body and tail, from which they get their common name, are also effective deterrents for unskilled divers (and me). The antennae also serve a sensory function, as do the smaller antennules. An additional mode of defense is to suddenly swim backwards, often startling divers. My son Kevin and nephew David had several ram into them as they were fleeing my lens on night dives... I assume they were camera shy.

Of course no description of a species would be complete without touching on the touchy subject of... er... propagation, aka mating. This pleasant activity takes place from January to April. The male and female mate by pressing their ventral sides together. Apparently the Kama Sutra has not been translated into "lobsterese." An unopened packet of sperm is transferred from the male to the female. When the lady is ready to bear young, she scratches open the packet with specialized claws while releasing her eggs. The bright red eggs attach to the underside of her tail and after about 10 weeks turn dark brown.

When they first reach sexual maturity, a female will produce about 100,000 eggs. Older and larger females may release nearly a million eggs. This far greater reproductive potential is a major reason why we need to protect the larger individuals to ensure good reproductive success. One way is to use slot limits, where lobster may only be taken between a minimum and maximum size limit. There are currently campaigns asking recreational divers to release the large lobster after they take their trophy pictures. Another way is to establish the marine reserves that are currently in the planning stages for California. Reserves established by Dr. Bill Ballantine in New Zealand have proven so successful that commercial crayfish (lobster) harvesters have pushed for additional reserves so they can benefit from the spillover into adjacent unprotected areas.

When the female is ready to release her eggs, as much as a month or two after actual mating, she goes to warmer, shallow water in May or June. The released eggs hatch into planktonic larvae known as phyllosoma. They drift there for six to nine months and may undergo 12 to 18 molts. This complex planktonic larval stage is the reason that lobster have not been successfully raised in aquaculture pens like salmon, white sea bass or abalone. Finally they reach the puerulus stage, and move close to shore where they molt again and settle as juvenile lobster.

Although the commercial catch has substantial impact on lobster populations, traps are designed to not capture the larger lobster. Recreational divers are the prime cause for the loss of the large "bull" lobster in nearshore waters. Prior to their harvest by SCUBA divers which began in the 1950s, lobster could live 150 years and reach a length of about one yard. According to Fish & Game, the record in California was a 16 pound bug taken off Catalina in 1968. It is said they can exceed 20 pounds if allowed to grow, and I saw one reference stating a 26 pounder had been taken. Today most legal lobster are captured when they are five to seven years old and have carapace lengths of 3 1/4 inches or more..

The commercial lobster fishery began in California during the late 1800s. In the early 1950s the harvest ranged into the 900,000 pound range. It did not reach this level again until 2002 when over 950,000 pounds were taken. The take fluctuates based on the health of the population as well as independent factors including oceanographic changes like water temperature, weather and the export market. To meet the high demand in California, spiny lobster are also imported from Mexico. It is interesting to note that despite being an economically important commercial target, little is known about the status of the spiny lobster population in our State. We do not have adequate benchmarks against which to judge the population's size, which in my mind makes managing the species much closer to guesswork than science.

Lobster season is defined as "from the Saturday preceding the first Wednesday in October through the first Wednesday after the 15th of March." This season will end on March 17, 2010. All individuals taking lobster must have a spiny lobster reporting card within easy access on the boat, or on shore if diving from a beach. The daily limit is stated as seven lobster. However, I've been informed by knowledgeable sources that this refers to ALL lobster in possession whether in your hand, in your bag or in your freezer. I'm hoping some of my bug bagging buddies will wander over to the island soon so I can place one or two in my freezer... or stomach!

© 2009 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!

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Lobster in open and in front of hiding place; lobster eating sea urchin and using antennae for defense.

This document maintained by Dr. Bill Bushing.
Material and images © 2009 Star Thrower Educational Multimedia