Caribbean lobster
| Caribbean lobster | ||||||||||||
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Caribbean lobster ( Panulirus argus ) |
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| Panulirus argus | ||||||||||||
| ( Latreille , 1804) |
The Caribbean lobster ( Panulirus argus ) is a decapod from the lobster family . It is native to the western Atlantic from Bermuda and the east coast of America from North Carolina to Brazil, as well as the Caribbean and the Gulf of Mexico. Its abdomen is a food, which is why it is fished in its entire range.
features
The maximum body length of this species of lobster is up to 45 centimeters, usually they reach a body length of 20 centimeters. The carapace is roughly cylindrical and covered with many spines and nodules of different sizes. The frontal horns are pronounced, sharp and clearly curved. The front edge of the carapace is smooth and without a rostrum. The antennae are long and stiff. The smaller antennae are rather fine. Their flagella are longer than their stems. There are two distinct spikes between the bases of the antennae. The abdomen and tail fan are comparatively strong. Each tergite of the abdomen is divided by a fully transverse depression. The dactyl of the striding legs is hairy. The endopodites of the pleopods are more developed in females than in males and are hook-shaped and provided with bristles. In males, the sternum is rather broader and without a corrugation that is found in females. The second pair of striding legs is the longest pair of legs in males. In females there are small chela on the fifth pair of striding legs.
Caribbean lobsters can be of different colors. Mostly they are blotchy greenish purple or light brown, reddish or bluish. On the first and last abdominal segment there are clearly white to yellow spots on the sides. In addition, other smaller points can appear on all segments. The tail fan has a dark red to brown rear edge. All striding legs have light and dark longitudinal lines. The pleopods are light orange to black.
Characteristic features of the Caribbean lobster are the four white dots on the body and the reddish-brown rear edge of the tail fan. Thus they can be of similar types Königslanguste ( Panulirus regius ) and Brown spiny lobster ( Panulirus echinatus ) relatively easy to distinguish.
ecology
distribution and habitat
The Caribbean lobster is native to the western Atlantic on the coasts of North and South America, as well as to the Caribbean and the Gulf of Mexico. The northern limit of their distribution area is around North Carolina , the southern one near Brazil. In the Eastern Atlantic, two finds are documented on the Ivory Coast. The establishment of a population was not observed there. The Caribbean lobster is also widespread near Cape Verde .
Each phase of their life cycle has a characteristic habitat. The Caribbean spiny lobster lives as a phyllosoma larva in planktonic form in surface waters at a relatively constant temperature and salinity. As post larvae that swim freely, Caribbean lobsters colonize a wide range of habitats, mostly in the bank area or in brackish water, but always in bank areas heavily overgrown with seagrass or algae. Especially algae of the genus Laurencia seem important for post larvae of the Caribbean lobster. These lobsters spend their first benthic stages in shallow water between seaweed and algae. When they are around two years old, they migrate to somewhat deeper zones. Adult Caribbean lobsters live in patch reefs , coral reefs or other habitats with solid or rocky subsoil at depths of no more than 90 meters. There they look for hiding places between or under rocks and reefs. Caribbean lobsters typically live in waters where the average minimum water temperature exceeds 20 ° C per month. Optimal growth occurs at temperatures between 26 and 28 ° C. A salt content below 16 ppt is no longer tolerated.
The Caribbean lobster migrates seasonally, it moves into deeper waters in autumn and winter. This can lead to mass migrations in which the lobsters run one behind the other and use the antennae to keep in contact with their front mate.
Life cycle
The phyllosoma larva, the characteristic larval type of the Achelata , is flattened from the back to the abdomen and has a bilobed cephalothorax . The limbs are long and hairy to aid levitation. By hitting the pairs of legs, they can swim. At night larvae swim to the surface of the water, while they sink a little during the day. There are a total of 11 phyllosoma larval stages, during which the larva grows from 2 to 34 millimeters in total length. After 6 to 12 months a metamorphosis takes place and the post-larval stage (puerulo larva) is reached. At this stage the larvae are still flattened from the back to the abdomen and are transparent, and the shell is not yet calcified. Puerulo larvae swim near the coast just a few centimeters below the surface of the water. This stage lasts for a few weeks, during which the larva does not eat. Caribbean lobsters then change to a benthic way of life, typically on the seabed overgrown with algae, mangroves or seaweed. A few days before they molt to reach the first juvenile stage, they first show signs of pigmentation. Young animals are spotty colored, provided with ribbons and stripes to ensure camouflage. Young animals are loners and behave aggressively towards other species. As they grow, they become more sociable. However, this change in behavior appears to be at least partially dependent on the availability of hiding places.
After a year, Caribbean lobsters are on average 5 centimeters long. Then they grow about 2.5 centimeters per year. Females grow a little slower than males. Moults occur on average 2.5 times a year, mostly in March to April and between December and February. The frequency of moulting and growth in length decrease with age. Food quality, population density, water temperature and injuries have a direct influence on growth.
Caribbean lobsters reach sexual maturity at a length of 7 to 8 centimeters. Mating takes place after a short courtship, during which both sexes send out signals. During copulation, the male transfers the packets of seeds that the female attaches to her sternum. The seed pacts remain there for up to a month. The female spawns by tucking her rump under the carapace and guiding the eggs past the seed pacts in order to fertilize them externally. The number of eggs depends on the size of the female. With a body length of about 7.5 centimeters, the number of eggs is about 230,000; with a body length of 38 centimeters approx. 2.6 million. The eggs are light orange and about 0.5 millimeters in diameter. They are attached to the swimming legs, where they stay for up to three weeks. A few days before the larvae hatch, the eggs are dark brown. The Caribbean lobster hatches as a transparent pyllosomal larva. During hatching, the female helps the larvae to spread apart by repeatedly bending the abdomen. In the Caribbean, a second spawning can be observed around a week after hatching, but with fewer eggs than the first time. Females usually molt immediately after their eggs hatch.
Diet and predators
The diet of the phyllosoma larva is hardly known. In culture they eat arrowworms , krill , fish larvae and rib jellyfish . As young animals living on the ground and fully grown animals, they are hunters and usually the dominant carnivore of their habitat. Prey are various animals, including snails , mussels , crustaceans , annelids and echinoderms, as well as beetle snails and carrion. Organisms with a shell are picked up with the legs and broken open or peeled with the strong mandibles.
The Caribbean lobster, in turn, is prey, especially as a larva. Phyllosoma larvae are eaten by various fish. Likewise the puerulo larva and young animals, which are also prey of other crabs or octopods. The predators of older Caribbean lobsters include groupers , sharks, the loggerhead turtle ( Caretta caretta ) and cephalopods and moray eels .
Use and endangerment
The Caribbean lobster is the most commercially important lobster of the genus Palinurus in American waters. It is fished in its entire range. This is usually done with traps, but also by hand or spear and by trawlers . The severed buttocks are sold fresh or frozen and exported in cans. In 1996 the total amount of landings was 37,723 tons. Countries with the largest quantities at that time were Cuba with 9,375 tons, Brazil with 8,026 tons and the Bahamas with 7,938 tons. Between 1996 and 2010 the amount of catches ranged between 30,000 and 40,000 tons.
In places this lobster is probably overfished. In addition, one in four animals is infected with virus 1 (Panulirus argus PaV1), which is fatal for lobsters. As a result, the population of the Caribbean lobsters is decreasing, at least regionally. In the IUCN Red List this Langustenart is unclassified because no data are available.
The fishing is regulated for conservation purposes. Specimens with a carapace of less than 69 millimeters and egg-bearing females may not be caught. In addition, fishing is prohibited between February and May while the females are spawning.
Individual evidence
- ↑ a b Species Fact Sheets Panulirus argus. Food and Agriculture Organization of the United Nations, accessed March 2, 2013 .
- ^ A b c d Lipke B. Holthuis : Marine Lobsters of the World . An Annotated and Illustrated Catalog of Species of Interest to Fisheries Known to Date. Ed .: Food and Agriculture Organization (= FAO Fisheries Synopsis . Volume 125 ). Rome 1991, ISBN 978-92-5103027-1 .
- ^ A b c d Eastern Central Atlantic Fishing Areas 34, 47 (in part) . In: W. Fischer, G. Bianchi, WB Scott (Eds.): FAO Species Identification Guide for Fishery Purposes . Vol. 5. Rome 1981 ( link to full text [accessed March 2, 2013]).
- ↑ a b c d e f g h i j K. Hill: Panulirus argus - Spiny Lobster. In: Smithsonian Marine Station at Fort Pierce. Retrieved March 2, 2013 .
- ↑ a b c Panulirus argus in the endangered Red List species the IUCN 2012. Posted by: M. Butler, A. Cockcroft, A. MacDiarmid, R. Wahle, 2011. Retrieved on March 2, 2013.
- ^ A b Caribbean Spiny Lobsters, Panulirus argus. MarineBio Conservation Society, accessed March 2, 2013 .
- ↑ MJ Butler, DC Behringer, JD Shields: Transmission of Panulirus argus virus 1 (PaV1) and its effect on the survival of juvenile Caribbean spiny lobster . In: Dis Aquat Organ . tape 79 , no. 3 , p. 173-182 , doi : 10.3354 / dao01899 .
