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Crabs Lobster And Their Kin - Part 1 - Lobsters
A Little Crab And Lobster Anatomy
Crabs and lobsters belong to a group of animals called the crustaceans. the body is made up of a head, a thorax, and an abdomen. In some types of these species the head and thorax are in one piece. The legs are jointed. Thus far, in this simple description you might think I could be speak of insects, and in fact, insects and crustaceans are related.
There is no backbone or any internal skeleton, but the body is covered with an external skeleton composed of chitin. This is a tough, horny external skeleton which is shed from time to time, to permit the animal to grow. A new larger skeleton then forms.
Crustaceans have no lungs but get oxygen by means of gills, somewhat as fishes do.
Kinds of Crustaceans
The crustacean group is well represented in the seas and in fresh water. There are even some types that live in damp places wholly on the land. In addition to crabs and lobsters, the group includes:
- Water fleas
- Fish lice
- Pill Bugs
- Beach Fleas
Some of these animals are of great value to man, either directly or indirectly, but as you shall see, some other species of this family can be a nuisance, to put it mildly.
General Crustacean Information
If you have ever examined a glass of water taken from a pond or from the ocean, you have probably seen some of the smaller members of this group.
For shallow waters teem with tiny crustaceans, many of them all but invisible unless you use a microscope. Some of these little fellows never grow any larger, but others are the young of big crustaceans.
These small crustaceans and the young of larger ones are important to us, indirectly. Without them, food for some of the larger animals, including fishes, would not be forthcoming. since we are very much interested in the fish supply across the world, the little crustaceans that nourish the fish have their place in the general food chain.
What do crustaceans eat? Both plant and animal matter. Many of these joint-legged animals are not too particular about the state of their food. They will eat it fresh or in a semi-decayed state. Not a few of them, including lobsters, crayfish, and crabs, act more or less as scavengers.
Crustacean History - The Lobster
The early North American settlers like lobsters, a lot. To many people, lobsters are the most delicious of all sea foods. Since the days of the first American settlements, they have been sought along the east coast from Gaspe Peninsula southward.
They have been eaten fresh, and canned for the inland trade. Now, thanks to modern freezing techniques and transportation by air, lobsters can be had almost anywhere and at any time.
The one we eat is the American lobster of the genus Homarus. This type bears the familiar pair of large claws, or pincers. Most lobsters that reach the table these days are less than two pounds in weight. However, much larger specimens, weighing about forty pounds are on record.
In the early days of American history, they were used for fertilizer for crops, a custom learned from the native Americans. They were fed to the poor and even to prisoners. They were so abundant that they were part of payment for indentured servants, who were subject to having to eat them so much, that some servants in Massachusetts actually revolted, demanding that they only be served lobster no more than three times a week.
For a long time, there was a time when lobsters could be purchased for ten cents a pound. New England canneries worked overtime during the lobster season. However, the gradually failing supply has put a permanent end to such conditions. By World War II, they were considered luxuries and quite expensive. That fact remains true today for the most part.
How Lobsters Are Harvested
There are a number of ways to catch lobsters. However, lobsters are generally caught in traps, or lobster pots, which are baited and lowered to the bottom. The entrance to the trap is an inverted cone, a sort of "one way street." It is easy to get in, but difficult to get out again.
The traps are hauled up periodically, the catch is removed, and the traps are put back in position. Natural supplies of lobsters have diminished so much that in this country there are laws that limit lobster fishing and especially commercial lobster enterprises, for which lobster permits are exceptionally expensive and hard to come by.
The Live Lobster
The live lobster is blue-black in coloration. When cooked, the shell turns red. Lobsters are bottom dwellers.
In the winter months they move offshore into depths up to five hundred feet. In the summer then return to the shallower water. On the bottom, lobsters take refuge under the sheltering overhang of rocks, from which point of vantage they may reach forth with their pincers to seize any food that comes their way. The adults thus enjoy a fair degree of security. However, it is just the opposite with their young.
A mature female lobster may produced ten thousand eggs per summer. She carries the mass of eggs attached to her abdomen until they hatch. During this period, the female is known to the trade as a "berried lobster."
When the eggs hatch, the young do not at first look like their parents. They are tiny, free-swimming crustaceans which take to the surface of the sea and remain there for three or four weeks. Therein lies the tragedy, for the surface of the sea is patrolled by hungry fish and birds that are prone to feast upon young lobsters. The toll of just the fish take is terrific.
Of course, mankind has now decided to help baby lobsters out, with the usual ulterior motive, more lobsters for us to eat when they mature and profits to be had. We now raise them in sheltered pools at hatcheries. The eggs are taken from the berried females that happened to be trapped by the fishermen. The eggs and the young that hatch from them are cared for and protected, and the growing crustaceans are either harvested or returned to the sea when they have reached a less hazardous bottom seeking stage.
It takes from six to ten years for a young lobster to attain a weight of a pound. During these years, it molts, or sheds its external skeleton, a number of times.
After it weighs two and a half pounds it is a "jumbo" and no longer the most sought after size, because the meat from the larger animals is inclined to be tough.
In restaurant language, "chicken lobsters" are those weighing about a pound and the most desirable. "Selects" are lobsters of intermediate size between the "chickens" and the "jumbos."
The Spiny Lobster of the Pacific Coast has no claws. They are the Spiny Lobsters of the West Indian and Pacific coast areas that are also sought after as food. These crustaceans look a good deal like the American Lobster, but lack the large claws or pincers.
They have unusually long antennae, and develop sharp spines on the upper surface and the sides of their bodies. Spiny Lobsters are often found in the shallow waters along reefs or in tide pools.
The European Lobster And Other Lobster Species
The European Lobster, captured along the shores of Norway, Great Britain, and Ireland, does not differ much from its American relative. It is occasionally found as far south as the Mediterranean.
The European Spiny Lobster is also very similar to the American species. It reaches a weight of fifteen to eighteen pounds.
Other species, the Senegal Lobster and the South African Spiny Lobsters, are exported to Europe and the United States.