Fish Facts

Frogfish (Antennariidae)

Sat, 05 Dec 2009 02:38:00 GMT

Frogfishes, family Antennariidae, are a type of anglerfish in the order Lophiiformes. They are known as anglerfishes in Australia, where 'frogfish' refers to a different type of fish. Frogfishes are found in almost all tropical and subtropical oceans and seas around the world, the primary exception being the Mediterranean Sea.

Features

A striated frogfish, with upturned mouth, very distinct spinules, and esca in the form of a white worm

Frogfish have a stocky appearance, atypical of fish. Ranging from 2.5-38cm (1-15 inches) long, their plump, high-backed, non-streamlined body is scaleless and bare, often covered with bumpy, bifurcated spinules. Their short bodies have between 18 and 23 vertebrae and their mouths are upward pointed with palatal teeth. They are often brightly colored, white, yellow, red, green, or black or spotted in several colors in order to blend in with their coral surroundings. Coloration can also vary within one species, making it difficult to differentiate between them.

Rather than typical dorsal fins, the front-most of the three fins is called the illicium or "rod" and is topped with the esca or "lure". The illicium often has striped markings, while the esca takes a different form in each species. Because of the variety of colors even within a single species, the esca and illicium is a useful tool to differentiate among different varieties. Some of them resemble fish, some shrimp, some polychaetes, some tubeworms, and some simply a formless lump; one genus, Echinophryne has no esca at all. Despite very specific mimicry in the esca, examinations of stomach contents do not reveal any specialized predation patterns, for example, only worm-eating fish. If lost, the esca can be regenerated. In many species the illicium and esca can be withdrawn into a depression between the second and third dorsal fins for protection when they are not needed.

Frogfish have small, round gill openings behind their pectoral fins. With the exception of Butler's Frogfish and the Rough Anglerfish, frogfish use a gas bladder to control their buoyancy.

Mimicry and camouflage

A frogfish disguised as an algae-covered stone

The unusual appearance of the frogfish is designed to conceal it from predators and sometimes to mimic a potential meal to its prey. In ethology, the study of animal behavior, this is known as aggressive mimicry. Their unusual shape, color, and skin textures disguise frogfish. Some resemble stones or coral while others imitate sponges, or sea squirtswith dark splotches instead of holes. In 2005, a species was discovered, the striated frogfish, that mimics a sea urchin while the sargassumfish is colored to blend in with the surrounding sargassum. Some frogfish are covered with algae or hydrozoa. Their camouflage can be so perfect, that sea slugs have been known to crawl over the fish without recognizing them.

For the scaleless and unprotected frogfish, the camouflage is an important defense against predators. Some frogfish can also inflate themselves, likepufferfish, by sucking in water in a threat display. In aquariums and in nature, frogfish have been observed, when flushed from their hiding spots and clearly visible, to be attacked by clownfish, damselfish, and wrasse, and in aquariums, to be killed.

Many frogfish can change their color. The light colors are generally yellows or yellow-browns while the darker are green, black, or dark red. They usually appear with the lighter color, but the change can last anywhere from a few days to several weeks. It is unknown what triggers the change.

Movement

Frogfish generally do not move very much, preferring to lie on the sea floor and wait for prey to approach. Once the prey is spotted, they can approach slowly using their pectoral and pelvic fins to walk along the floor. They have two "gaits" that they can use. In the first they alternately move their pectoral fins forward, propelling themselves somewhat like a two-legged tetrapod, leaving the pelvic fins out. Alternately, they can move in something like a slow gallop, whereby they move their pectoral fins simultaneously forward and back, transferring their weight to the pelvic fins while moving the pectorals forward. With either gait, then can only cover short stretches.

In open water, frogfish can swim with strokes of the tail fin. They also have a kind of jet propulsion that is often used by younger frogfish. It is achieved by rhythmically forcing their breath-water out through their gill openings, which lie behind their pelvic fins.

The sargassum frogfish has adapted fins which can grab strands of sargassum, enabling it to "climb" through the seaweed.

Hunting

A spotfin frogfish waiting amid the coral

Frogfish eat crustaceans, other fish, and even each other. When potential prey is first spotted, the frogfish follows it with its eyes. Then, when it approaches within roughly seven body-lengths, the frogfish begins to move its illicium in such a way that the esca mimics the motions of the animal it resembles. As the prey approaches, the frogfish will slowly move itself to prepare for its attack; sometimes this involves approaching the prey or "stalking" while sometimes it is simply adjusting its mouth angle. The catch itself is made by the sudden opening of the jaws, which enlarges the volume of the mouth cavity up to twelve-fold, pulling the prey into the mouth along with water. The water flows out through the gills, while the prey is swallowed and the esophagus closed with a special muscle to keep the victim from escaping. In addition to expanding their mouths, frogfish can also expand their stomachs to swallow animals up to twice their size.

Slow-motion filming has shown that the frogfish sucks in its prey in just six milliseconds, so fast that other animals can't see it happen. This is less time than it takes a muscle to contract so the source of the motion remains unknown. Frogfish have also been observed to eat lionfish; the latter's poison appears to have no effect.

Reproduction

The reproductive behavior of the normally solitary frogfish is still not fully researched. There are few observations in aquariums and even fewer from the wild. Most species are free-spawning, with females laying the eggs in the water and males coming in behind to fertilize them. Anywhere from eight hours to several days before the egg-laying, the abdomen of the female starts to swell as the eggs absorb water, sometimes as many as 180,000 eggs.^[5] The male begins to approach the female around two days before the spawning. It is not known if the spawn is predetermined by some external factor, such as the phase of the moon, or if the male is attracted to a smell or signal released by the female. In all hitherto observed breeding pairs, one partner was noticeably, sometimes as much as ten times, larger than the other. When the gender could be determined, the larger partner was always the female.

During the free-spawning courtship ritual, the male swims beside and somewhat behind the female, nudges her with his mouth then remains near her cloaca. Just before the spawning, the female begins to swim above the ocean floor toward the surface. At the highest point of their swim they release the eggs and sperm before descending back. Sometimes the male pulls the eggs out of the female with his mouth. After mating the partners depart quickly as otherwise the smaller male would likely be eaten. A few species are subtrate-spawners, notably the genuses Lophiocharon, Phyllophryne, and Rhycherus which lay their eggs on a solid surface like a plant or rock. Some species guard their eggs, a duty assigned to the male in almost all species, while most others do not.^[6]^[5] Several species practice brood carrying, for example the three-spot frogfish, whose eggs are attached the male, and those in the genus histiophryne, whose brood are carried in the pectoral fins.

The eggs are .5-1mm (.02-.04in) large and cohere in a gelatinous mass or long ribbon, which in Sargassumfish are up to a meter (3.3 ft) long and 16cm (6 in) wide. These egg masses can include up to 180,000 eggs.^[5]^[10] For most species, the eggs drift on the surface. After two to five days, the fish hatch and the newly hatched alevin are between .8 and 1.6 mm long (.03 and .07 in). For the first few days they live on the yolk sac while their digestive systems continue to develop. The young have long fin filaments and can resemble tiny, tentacled jellyfish. For one to two months they live planktonically. After this stage, at a length of between 15 and 28 mm (.6-1.1 in), they have the form of adult frogfish and begin their lives on the sea floor. Young frogfish often mimic the coloration of poisonous sea slugs or flatworms.

Species

Commerson's Frogfish, Kona,Hawaii, Antennarius commerson.

Ocellated frogfish, Bonaire,Netherlands Antilles, Antennarius ocellatus.

Red Ocellated frogfish, St. Kitts.Antennarius ocellatus.

Long-lure frogfish, Bonaire,Netherlands Antilles, Antennarius multiocellatus.

Painted frogfish, Antennarius pictus

Clown frogfish, Antennarius maculatus

Within the family Antennariidae there are 45 species in twelve genera:

Genus Allenichthys
- Glauert's anglerfish, Allenichthys glauerti (Whitley, 1944).
Genus Antennarius
- Tail-jet frogfish, Antennarius analis (Schultz, 1957).
- Roughbar frogfish, Antennarius avalonis Jordan & Starks, 1907.
- Island frogfish, Antennarius bermudensis Schultz, 1957.
- Brackishwater frogfish, Antennarius biocellatus (Cuvier, 1817).
- Scarlet frogfish, Antennarius coccineus (Lesson, 1831).
- Commerson's frogfish, Antennarius commerson (Latreille, 1804).
- New Guinean frogfish, Antennarius dorehensis Bleeker, 1859.
- Side-jet frogfish, Antennarius duescus Snyder, 1904.
- Shaggy angler, Antennarius hispidus (Bloch & Schneider, 1801).
- Indian frogfish, Antennarius indicus Schultz, 1964.
- Warty frogfish, Antennarius maculatus (Desjardins, 1840).
- Longlure frogfish, Antennarius multiocellatus (Valenciennes, 1837).
- Spotfin frogfish, Antennarius nummifer (Cuvier, 1817).
- Ocellated frogfish, Antennarius ocellatus (Bloch & Schneider, 1801).
- Antennarius pardalis (Valenciennes, 1837).
- Dwarf frogfish, Antennarius pauciradiatus Schultz, 1957.
- Painted frogfish, Antennarius pictus (Valenciennes, 1837).
- Singlespot frogfish, Antennarius radiosus Garman, 1896.
- Randall's frogfish, Antennarius randalli Allen, 1970.
- Spiny-tufted frogfish, Antennarius rosaceus Smith & Radcliffe, 1912.
- Bloody frogfish, Antennarius sanguineus Gill, 1863.
- Calico frogfish, Antennarius sarasa Tanaka, 1916.
- Antennarius scriptissimus Jordan, 1902.
- Senegalese frogfish, Antennarius senegalensis Cadenat, 1959.
- Striated frogfish, Antennarius striatus (Shaw, 1794).
Genus Antennatus
- Antennatus flagellatious Ohnishi, Iwata & Hiramatsu, 1997.
- Antennatus linearis Randall & Holcom, 2001.
- Bandtail frogfish, Antennatus strigatus (Gill, 1863).
- Tuberculated frogfish, Antennatus tuberosus (Cuvier, 1817).
Genus Echinophryne
- Prickly anglerfish, Echinophryne crassispina McCulloch & Waite, 1918.
- Long-spined anglerfish, Echinophryne mitchellii (Morton, 1897).
- Echinophryne reynoldsi Pietsch & Kuiter, 1984.
Genus Histiophryne (Gill, 1863)
- Histiophryne bougainvilli (Valenciennes, 1837).
- Cryptic anglerfish, Histiophryne cryptacanthus (Weber, 1913).
- Histiophryne psychedelica (Pietsch, 2009)^[12]
Genus Histrio
- Sargassumfish, Histrio histrio (Linnaeus, 1758).
Genus Kuiterichthys
- Rough anglerfish, Kuiterichthys furcipilis (Cuvier, 1817).
Genus Lophiocharon
- Marble-mouthed frogfish, Lophiocharon lithinostomus (Jordan & Richardson, 1908).
- Three-spot frogfish, Lophiocharon trisignatus (Richardson, 1844).
- Lophiocharon hutchinsi (TW Pietsch, 2004)
Genus Nudiantennarius
- Deepwater frogfish, Nudiantennarius subteres (Smith & Radcliffe, 1912).
Genus Phyllophryne
- Smooth anglerfish, Phyllophryne scortea (McCulloch & Waite, 1918).
Genus Rhycherus
- Tasselled anglerfish, Rhycherus filamentosus (Castelnau, 1872).
- Rhycherus gloveri Pietsch, 1984.
Genus Tathicarpus
- Butler's frogfish, Tathicarpus butleri Ogilby, 1907.

References

^ "Antennariidae". FishBase. Ed. Rainer Froese and Daniel Pauly. February 2006 version. N.p.: FishBase, 2006.
^ ^a ^b ^c ^d ^e Antennariidae: Frogfishes Tree of Life Web Project
^ "Antennarius biocellatus". FishBase. Ed. Ranier Froese and Daniel Pauly. Sep 2009 version. N.p.: FishBase, 2009.
^ "Histrio histrio". FishBase. Ed. Ranier Froese and Daniel Pauly. Sep 2009 version. N.p.: FishBase, 2009.
^ ^a ^b ^c ^d Diving with Frogfish Dive the World 2009
^ ^a ^b ^c ^d ^e ^f Frogfish Factsheet Shedd Aquarium Explore by Animal 2009
^ "Histrio histrio". FishBase. Ed. Ranier Froese and Daniel Pauly. Sep 2009 version. N.p.: FishBase, 2009.
^ Lloyd, Robin Crawling fish accepted as new species MSNBC.com
^ ^a ^b Bertelsen, E. & Pietsch, T.W. (1998). Paxton, J.R. & Eschmeyer, W.N.. ed. Encyclopedia of Fishes. San Diego: Academic Press. pp. 138-139. ISBN 0-12-547665-5.
^ Frogfish spawn on Valentine's Day National Sea Life Center, Birmingham
^ G. Carnevale1 & T.W. Pietsch: Filling the gap: a fossil frogfish, genus Antennarius (Teleostei, Lophiiformes, Antennariidae), from the Miocene of Algeria [Abstract
^ Theodore W. Pietsch, Rachel J. Arnold, and David J. Hall (2008-10-17 (submitted 2008-08-01)). "[http://www.finsonline.com/podcasts/pdfs/2009/psychedelica.pdf A Bizarre New Species of Frogfish of the Genus Histiophryne (Lophiiformes: Antennariidae) from Ambon and Bali, Indonesia]". School of Aquatic and Fishery Sciences, and Burke Museum of Natural History and Culture, University of Washington, Campus Box 355020,Seattle, Washington 98195; E-mail: (TWP) twp@u.washington.edu; and (RJA) schoenrj@u.washington.edu. Copeia (2009, No. 1, 37–45). Retrieved 2009-02-27.

Pietsch and Grobecker, 1987. Frogfishes of the World. Stanford University Press.

Hermit Crabs, (Paguroidea)

Sat, 05 Dec 2009 08:11:00 GMT

Hermit crabs are decapod crustaceans of the superfamily Paguroidea. They are not closely related to true crabs. Hermit crabs are quite commonly seen in the intertidal zone: for example, in tide pools.

Most species have long, soft abdomens which are protected from predators by a salvaged empty seashell carried on the crab's back, into which the crab's whole body can retract. Most frequently hermit crabs use the shells of sea snails; the tip of the hermit crab's abdomen is adapted to clasp strongly onto the columella of the snail shell ^[. As the hermit crab grows in size, it has to find a larger shell and abandon the previous one. This habit of living in a second hand shell gives rise to the popular name "hermit crab", by analogy to a hermit living alone.

Hermit crabs

Scientific classification

Kingdom: Animalia

Phylum: Arthropoda

Subphylum: Crustacea

Class: Malacostraca

Order: Decapoda

Suborder: Pleocyemata

Infraorder: Anomura

Superfamily: Paguroidea
Latreille, 1802

Of about five hundred known species, most are aquatic and live in varying depths of saltwater, from shallow reefs and shorelines to deep sea bottoms. However, tropical areas host some terrestrials. Some of these are quite large, such as Petrochirus diogenes.
A number of other species, most notably king crabs, have abandoned seashells; these species are more similar in form to true crabs, and are known as carcinised hermit crabs

Hermit crabs

Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Anomura
Superfamily:	Paguroidea Latreille, 1802

.As hermit crabs grow they require larger shells. Since suitable intact gastropod shells are a limited resource, there is frequently strong competition among hermit crabs for shells. The availability of empty shells at any given place depends on the relative abundance of gastropods and hermit crabs, matched for size. An equally important issue is the population of organisms that prey upon gastropods and leave the shells intact .

A hermit crab with a too-small shell cannot grow as fast as those with well-fitting shells, and is more likely to be eaten if it cannot hide in the shell.

For some larger marine species, supporting one or more sea anemones on the shell can scare away predators. The sea anemone benefits because it is in position to consume fragments of the hermit crab's meals.

Development and reproduction

Hermit crab species range in size, shape, from species with a carapace only a few millimetres long to Coenobita brevimanus which can approach the size of a coconut. The shell-less hermit crab Birgus latro is the world's largest terrestrial invertebrate .

The male's reproductive organs are located near and just below the heart and open to the outside at the base of the hindmost pair of walking legs. In the female, they are located at the base of the middle pair of walking legs. Females usually lay their eggs shortly after copulating, but they can also store sperm for many months. The eggs become fertilised as they passing through the chamber holding the sperm just before laying. The mother carries the eggs in a mass attached to her abdomen inside the shell. The number of eggs is usually large, but depends on the animal's size.

The young develop in stages, with the first two (the nauplius and protozoea) occurring inside the egg. Most hermit crab larvae hatch at the third stage, the zoea. This is a larval stage wherein the crab has several long spines, a long narrow abdomen, and large fringed antennae. After several zoeal moults, this is followed by the final larval stage, the megalopa stage .

Terrestrial hermit crabs begin life in the sea, but become air-breathers via moulting. After the final developmental moult, the youngster must live mostly on land. Its link with the sea is never entirely broken however, because it always carries a small amount of water in its shell to moisten its abdomen and hydrate its modified gills.

Juvenile land hermit crabs move away from the water. They then grow and develop through moulting in which they shed their exoskeleton. During moulting, they are extremely vulnerable and inactive, and usually burrow in the ground for protection. The new exoskeleton hardens and the crab regenerates lost or broken claws or legs in around 10 days. A hermit crab can moult as often as every other month when young, and every 18 months when they are older.

Hermit crabs release their eggs in the ocean, near the shore. Because of this, it is very hard to breed hermit crabs in captivity. Little is known about reproduction in captivity. E.g., whether seasonal changes contribute to the animals' mating patterns. Some studies suggest that captive males become more sexually interested if they have brightly colored shells, possibly increasing their self-confidence. Breeding requires near-perfect conditions and even then, after the eggs hatch, they may die from inappropriate food and water.

Hawksbill Turtle, (Eretmochelys imbricata)

Mon, 09 Nov 2009 08:51:00 GMT

The hawksbill turtle (Eretmochelys imbricata) is a critically endangered sea turtle belonging to the family Cheloniidae. It is the only species in its genus. The species has a worldwide distribution, with Atlantic and Pacific subspecies. Eretmochelys imbricata imbricata is the Atlantic subspecies, while Eretmochelys imbricata bissa is found in the Indo-Pacific region.

The hawkbill's appearance is similar to that of other marine turtles. It has a generally flattened body shape, a protective carapace, and its flipper-like arms are adapted for swimming in the open ocean. E. imbricata is easily distinguished from other sea turtles by its sharp, curving beak with prominent tomium, and the saw-likeappearance of its shell margins. While the turtle lives a part of its life in the open ocean, it is most often encountered in shallow lagoons and coral reefs where it feeds on its chosen prey, sea sponges. Some of the sponges eaten by E. imbricata are known to be highly toxic and lethal when eaten by other organisms. In addition, the sponges that hawksbills eat are usually those with high silica content, making the turtles one of few animals capable of eating siliceous organisms. They also feed on other invertebrates, such as comb jellies and jellyfish.

Because of human fishing practices, Eretmochelys imbricata populations around the world are threatened with extinction and the turtle has been classified as critically endangered by the World Conservation Union. Several countries, such as China and Japan, have valued hunting hawksbill turtles for their flesh, which is considered good eating. Hawksbill turtle shells are the primary source of tortoise shell material, used for decorative purposes. By the Convention on International Trade in Endangered Species, it is illegal to capture and to trade in hawksbill turtles and products derived from them in many nations.

Ecology and life history

Habitat

Adult hawksbill turtles are primarily found in tropical coral reefs. They are usually seen resting in caves and ledges in and around these reefs, throughout the day. As a highly migratory species, they have also been encountered in a wide range of habitats, from the open ocean to lagoons and een mangrove swamps in estuaries. While much is not known about the habitat preferences of early-life stage E. imbricata, like other sea turtles' young, they are assumed to be completely pelagic and thus make the open sea their home until they mature.

Feeding ecology

E. imbricata in a coral reef inVenezuela.

While they are known to be omnivorous, the principal food of hawkbill turtles are sponges. Sponges constitute 70 – 95% of the diets of E. imbricata populations in the Caribbean. However like many spongivores, E. imbricata feed only on a few select species, and will ignore many others. The Caribbean hawksbill populations were found to feed primarily on sponges from the class Demospongiae, specifically ones belonging to the orders Astrophorida, Spirophorida and Hadromerida. Select sponge species known to be fed on by these turtles include Geodia gibberosa. Aside from sponges, hawksbills also feed on algae and cnidarians like jellyfish and sea anemones. The hawksbill is also known to feed on the dangerous jellyfish-like hydrozoan, the Portuguese Man o' War (Physalia physalis). Hawksbills close their unprotected eyes when they feed on these cnidarians, for Man o' War's stinging cells cannot penetrate the turtles' armoured heads.

Eretmochelys imbricata have shown themselves to be highly resilient and resistant to their prey. Some of the sponges known to be eaten by hawksbills, such as Aaptos aaptos,Chondrilla nucula, Tethya actinia, Spheciospongia vesparium and Suberites domuncula, are highly (often lethally) toxic to other organisms. In addition, hawksbills are known to choose sponge species that have a significant amount of siliceous spicules, such as Ancorina, Geodia, Ecionemia and Placospongia.

[edit]Life history

Young E. imbricata from Réunion Island.

Much is not known about the life history of Eretmochelys imbricata. Hawksbills are known to mate biyearly in secluded lagoons in remote islands throughout their range. Mating season for Atlantic hawksbills usually takes place from April to November. For Indian Ocean populations such as the Seychelles hawksbill population, the mating season is from September to February. As with other sea turtles, hawksbills mate in shallow lagoons off the shores of their prospective nesting beaches. After mating, the females drag their heavy bodies high onto the beach during the night. They will then clear out an area and dig a nesting hole using their rear flippers. The female then lays a clutch of eggs in the nest and then covers them with sand. Caribbean and Florida nests of E. imbricata normally contain around 140 eggs. After the several-hour-long process, the female then returns to the sea. This is the only time when hawksbill turtles are known to leave the ocean.

The baby turtles, usually weighing less than two dozen grams, hatch during the night after around two months. These newly emergent hatchlings are dark-colored, with heart-shaped carapaces measuring around 2.5 centimetres (1 in) long. They instinctually head for the sea, attracted by the reflection of the moon on the water (a mechanism which can be disrupted by anthropogenic light sources such as street lamps and lights). While they emerge under the cover of darkness, baby turtles that do not reach the water by daybreak are preyed upon by predators such as shorebirds and shore crabs.

E. imbricata hatchling in Puerto Rico.

The early life history of juvenile hawksbill turtles is unknown. Upon reaching the sea, the hatchlings are assumed to enter a pelagic life stage (like other marine turtles) for an undetermined amount of time. While hawksbill turtle growth rates are not known, when E. imbricata juveniles reach around 35 cm, they switch from a pelagic life style to a coral reef-associated one. Hawksbill turtles are hypothesized to reach maturity after thirty years.

While there is no clear consensus because of a lack of data, hawksbill turtles are believed to live from thirty to fifty years in the wild. Like other sea turtles, hawksbill turtles are solitary for most of their lives, they only group together to mate. They were once thought to be habitual, but they are now known to be highly migratory. Because of their tough carapaces, hawksbill turtles have no major predators as there are few creatures that are capable of biting through their protective shell. Sharks and estuarine crocodiles are a few of their natural predators. Octopuses and some species of pelagic fish have also been known to prey on the adult turtles.

Evolutionary history

Within the sea turtles, Eretmochelys imbricata has several unique anatomical and ecological traits, including being the only primarily spongivorous reptile known. Because of this, its evolutionary position has been somewhat unclear. Molecular analyses supports the probability that the Eretmochelydae evolved from carnivorous ancestors rather than herbivorous ones. As the taxonomic tribeCarettini is composed of carnivorous species (such as the loggerhead turtle), the hawksbill most probably evolved from them instead of the herbivorous Chelonini, which includes the green turtle.

Etymology and taxonomic history

Hawksbill turtle (top right) in a 1904 plate byErnst Haeckel.

The hawksbill turtle was originally described by Carolus Linnaeus as Testudo imbricata in 1766. It was moved into the genus Eretmochelys by the Austrian zoologist Leopold Fitzinger in 1843. In 1857, the species was redescribed as Eretmochelys imbricata squamata, a designation that is now invalid.

There are two accepted subspecies in the E. imbricata taxon. Eretmochelys imbricata bissa (Rüppell, 1835) refers to all known populations of the Eretmochelys imbricata that reside in thePacific Ocean. The Atlantic population has been found to be a separate subspecies, Eretmochelys imbricata imbricata (Linnaeus, 1766). The subspecies name of imbricata was retained because the type specimen that Linnaeus used to initially describe the species was from the Atlantic.

Fitzinger derived the genus' name, Eretmochelys from the Greek roots eretmo and chelys, corresponding to "oar" and "turtle" respectively. The name refers to the turtles' oar-like front flippers. The species' name imbricata is Latin, corresponding to the English term imbricate. This appropriately describes the turtles' overlapping posterior scutes. The Pacific hawksbill's subspecies name, bissa is Latin for "double". The subspecies was originally described as Caretta bissa and the term referred to the then-species' being the second species in the genus. Caretta is the genus of the hawksbill's much larger relative, the loggerhead turtle.

Conservation

General consensus has determined sea turtles, including Eretmochelys imbricata to be at the very least, threatened species because of their long lifespans, slow growth and maturity, and slow reproductive rates. Many adult turtles have been killed by humans both deliberately and incidentally. In addition, the nesting sites of the turtles are also threatened by human and animal encroachment. Small mammals have been known to raid the nesting sites and dig up the turtles' eggs. In the U.S. Virgin Islands, Eretmochelys imbricata nests (along with the nests of other sea turtles like Dermochelys coriacea) are often raided bymongooses right after being laid.

A hawksbill turtle in Tobago.

In 1996, the IUCN Red List of Threatened Species classified Eretmochelys imbricata as critically endangered.^[1] Its status as an endangered species was challenged prior to this, with two petitions claiming that the turtle (along with three other species) had several significant stable populations worldwide. These petitions were rejected by the IUCN based on their analysis of data submitted by the Marine Turtle Specialist Group (MTSG). The data given by the MTSG showed that the worldwide population of hawksbill turtles had been reduced by 80% in the last three of the species' generations, and that was no significant increase in the turtles' populations as of 1996. In light of this data, the IUCN applied thecritically endangered (A1) status upon the species. CR A2 status was denied however, because the IUCN believed that there was insufficient data to show that the population of hawksbill turtles were due to decrease by a further 80% in the future.

Historically, Eretmochelys imbricata was first listed as endangered by the IUCN in 1982. This endangered status continued all the way through several reassessments in 1986, 1988,1990 and 1994 until it was upgraded in status to critically endangered in 1996 (see above).

The species (along with the entire family Cheloniidae) has been listed on Appendix I of the Convention on International Trade in Endangered Species. It is illegal to import or export turtle products, kill, capture or harass hawksbill turtles

Local involvement in the conservation efforts for the species have also increased in the past few years. The United States Fish and Wildlife Service and National Marine Fisheries Service have classified the hawksbill turtle as endangered under the Endangered Species Act since 1970. The U.S. government has several recovery plans in place for protecting its populations of E. imbricata.

References

^ ^a ^b ^c Red List Standards & Petitions Subcommittee (1996). Eretmochelys imbricata. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on February 5, 2007.
^ Eretmochelys imbricata (TSN 173836). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ ^a ^b ^c ^d ^e "Species Booklet: Hawksbill sea turtle". Virginia Fish and Wildlife Information Service. Virginia Department of Game & Inland Fisheries. Retrieved 2007-02-06.
^ ^a ^b CITES (2006-06-14). "Appendices" (SHTML). Convention on International Trade in Endangered Species of Wild Flora and Fauna. Retrieved 2007-02-05.
^ "Hawksbill turtle - Eretmochelys imbricata: More information". Wildscreen. Retrieved 2007-02-05.
^ ^a ^b ^c ^d ^e ^f ^g "Eretmochelys imbricata, Hawksbill Sea Turtle". MarineBio.org. Retrieved 2007-02-05.
^ "The Hawksbill Turtle (Eretmochelys imbricata)". turtles.org. Retrieved 2007-02-22.
^ ^a ^b ^c "Hawksbill". SeychellesTurtles.org - Strategic Management of Turtles. Marine Conservation Society, Seychelles. Retrieved 2007-02-22.
^ "The Hawksbill Turtle: Eretmochelys imbricata". Auckland Zooaccessdate = 2007-07-14.
^ ^a ^b ^c "Species Fact Sheet: Eretmochelys imbricata (Linnaeus, 1766)". FIGIS - Fisheries Global Information System. United Nations. 2006. Retrieved 2009-06-14.
^ ^a ^b ^c "Hawksbill Sea Turtle (Eretmochelys imbricata)". North Florida Field Office. United States Fish and Wildlife Service. 2005-12-09. Retrieved 2007-02-18.
^ ^a ^b Pope, C. H. (1939). Turtles of the United States and Canada. New York: Alfred A. Knopf.
^ ^a ^b Formia, Angela; Manjula Tiwari, Jacques Fretey and Alexis Billes (2003). "Sea Turtle Conservation along the Atlantic Coast of Africa". Marine Turtle Newsletter (IUCN Marine Turtle Specialist Group) 100: 33 – 37. Retrieved 2007-02-18.
^ ^a ^b Heppel, Selina S.; Larry B. Crowder (June 1996). "Analysis of a Fisheries Model for Harvest of Hawksbill Sea Turtles (Eretmochelys imbricata)". Conservation Biology (Blackwell Publishing) 10 (3): 874 – 880. doi:10.1046/j.1523-1739.1996.10030874.x. Retrieved 2007-02-16.
^ Bowen, B. W.; A. L. Bass, A. Garcia-Rodriguez, C. E. Diez, R. van Dam, A. Bolten, K. A., Bjorndal, M. M. Miyamoto and R. J. Ferl (May 1996). "Origin of Hawksbill Turtles in a Caribbean Feeding Area as Indicated by Genetic Markers". Ecological Applications (The Ecological Society of America) 6 (2): 566 – 572. doi:10.2307/2269392. Retrieved 2007-02-16.
^ Colacion, Artem; Danee Querijero (2005-03-10). "Uriel’s journey home — a Young pawikan’s story in Boracay". The Philippine STAR. Retrieved 2007-02-06.
^ "Ocean Ambassadors - Philippine Turtle Islands". Coastal Resource & Fisheries Management of the Philippines. OneOcean.org. Retrieved 2007-02-06.
^ Loop, K. A.; J. D. Miller and C. J. Limpus (1995). "Nesting by the hawsbill turtle (Eretmochelys imbricata) on Milman Island, Great Barrier Reef, Australia". Wildlife Research (CSIRO Publishing) 22 (2): 241 – 251. doi:10.1071/WR9950241. ISSN: 1035-3712. Retrieved 2007-02-21.
^ Hitchins, P. M.; O. Bourquin and S. Hitchins (2004-04-27). "Nesting success of hawksbill turtles (Eretmochelys imbricata) on Cousine Island, Seychelles". Journal of Zoology (Cambridge University Press, The Zoological Society of London) 264(2): 383 – 389. doi:10.1017/S0952836904005904. Retrieved 2007-02-21.
^ Lutz, P. L.; J. A. Musick (1997). The Biology of Sea Turtles. Boca Raton, Florida: CRC Press.
^ Houghton, Jonathan D. R.; Martin J. Callow, Graeme C. Hays (2003). "Habitat utilization by juvenile hawksbill turtles (Eretmochelys imbricata, Linnaeus, 1766) around a shallow water coral reef" (PDF). Journal of Natural History 37: 1269 – 1280.doi:10.1080/00222930110104276. Retrieved 2007-03-17.
^ ^a ^b Meylan, Anne (1988-01-22). "Spongivory in Hawksbill Turtles: A Diet of Glass". Science (American Association for the Advancement of Science) 239 (4838): 393 – 395. doi:10.1126/science.239.4838.393. Retrieved 2007-02-15.
^ ^a ^b ^c Edelman, Michael (2004). "ADW: Eretmochelys imbricata: Information". Animal Diversity Web. University of Michigan Museum of Zoology. Retrieved 2007-02-04.
^ "Atlantic Hawksbill Sea Turtle Fact Sheet". New York State Department of Environmental Conservation. Retrieved 2009-06-10.
^ Bowen, Brian W.; William S. Nelson and John C. Avise (1993-06-15). "A Molecular Phylogeny for Marine Turtles: Trait Mapping, Rate Assessment, and Conservation Relevance" (PDF). Proceedings of the National Academy of Sciences of the United States of America (National Academy of Sciences) 90 (12): 5574 – 5577. doi:10.1073/pnas.90.12.5574. Retrieved 2007-02-16.
^ Testudo imbricata (TSN 208664). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ Eretmochelys (TSN 173835). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ Eretmochelys imbricata squamata (TSN 208665). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ Eretmochelys imbricata bissa (TSN 208666). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ Eretmochelys imbricata imbricata (TSN 173836). Integrated Taxonomic Information System. Retrieved on 5 February 2007.
^ Beltz, Ellin. "Translations and Original Descriptions: Turtles". Scientific and Common Names of the Reptiles and Amphibians of North America - Explained. ebeltz.net. Retrieved 2007-02-06.
^ ^a ^b UNEP-WCMC. "Eretmochelys imbricata". UNEP-WCMC Species Database: CITES-Listed Species. United Nations Environment Programme - World Conservation Monitoring Centre. Retrieved 2007-02-05.
^ ^a ^b Schafer, Edward H. (1962). "Eating Turtles in Ancient China". Journal of the American Oriental Society (American Oriental Society) 82 (1): 73 – 74. doi:10.2307/595986. Retrieved 2007-02-16.
^ Strieker, Gary (2001-04-10). "Tortoiseshell ban threatens Japanese tradition". CNN.com/sci-tech (Cable News Network LP, LLLP.). Retrieved 2007-03-02.
^ Casson, Lionel (1982). "Periplus Maris Erythraei: Notes on the Text". The Journal of Hellenic Studies (The Society for the Promotion of Hellenic Studies) 102: 204 – 206. doi:10.2307/631139. Retrieved 2007-02-16.
^ "Turtles of the Caribbean: the curse of illegal trade". Newsroom. World Wide Fund for Nature. 2006-10-01. Retrieved 2007-02-27.
^ Nellis, David W.; Vonnie Small (June 1983). "Mongoose Predation on Sea Turtle Eggs and Nests" (PDF). Biotropica (The Association for Tropical Biology and Conservation) 15 (2): 159 – 160. doi:10.2307/2387964. Retrieved 2007-02-16.
^ Red List Standards & Petitions Subcommittee (2001-10-18). "Ruling of the IUCN Red List Standards and Petitions Subcommittee on Petitions against the 1996 Listings of Four Marine Turtle Species, 18 October 2001" (PDF). International Union for Conservation of Nature and Natural Resources. Retrieved 2007-02-05.
^ Groombridge, B. (1982). The IUCN Amphibia-Reptilia Red Data Book, Part 1: Testudines, Crocodylia, Rhynocehapalia. Gland, Switzerland: IUCN.
^ IUCN Conservation Monitoring Centre (1986). 1986 IUCN Red List of Threatened Animals. Gland, Switzerland and Cambridge, UK: IUCN.
^ IUCN Conservation Monitoring Centre (1988). 1988 IUCN Red List of Threatened Animals. Gland, Switzerland and Cambridge, UK: IUCN.
^ IUCN (1990). 1990 IUCN Red List of Threatened Animals. Gland, Switzerland and Cambridge, UK.: IUCN.
^ Groombridge, B. (1994). 1994 IUCN Red List of Threatened Animals. Gland, Switzerland: IUCN.
^ "Species Profile: Hawksbill sea turtle (Eretmochelys imbricata)". USFWS Threatened and Endangered Species System (TESS). United States Fish and Wildlife Service. 1970-06-02. Retrieved 2007-02-05.

Trumpetfish, (Aulostomus maculatus)

Sun, 08 Nov 2009 09:37:00 GMT

Trumpetfish, Aulostomus maculatus, are long bodied fish with upturned mouths, that often swim vertically while trying to blend with vertical coral, like sea rods, sea pens, and pipe sponges.

Habitat

Trumpetfish occur in waters between 0.5 and 30 meters (1.6 and appr. 100 feet) deep and can grow to 40 to 80 cm (appr. 15 to 31 inches) in length. They are sometimes locally abundant over coral atoll reefs or in lagoons, where they may be caught even in areas of severe wave action. The spawning habits of the trumpetfish are unknown, but in the region around Madeira, it is known that the females have mature eggs from March to June.

Description

Trumpetfish are closely related to cornetfish. Trumpetfish can a bit more than 2 ft (60 cm) long and have greatly elongated bodies with small jaws at the front end of a long, tubular snout. The gills are pectinate, resembling the teeth of a comb, and a soft dorsal fin is found near the tail fin. A series of spines occurs in front of the dorsal fin. Trumpetfish vary in color from dark brown to greenish but also yellow in some areas. A black streak, sometimes reduced to a dark spot, occurs along the jaw, and a pair of dark spots is sometimes found on the base of the tail fin.

Trumpetfish swim slowly, sneaking up on unsuspecting prey, or lie motionless like a floating stick, swaying back and forth with the wave action of the water. They are adept at camouflaging themselves and often swim in alignment with other larger fishes. They feed almost exclusively on small fish, such as wrasses and atheriniformes,by sucking them suddenly into their small mouths.

A yellow trumpetfish

Trumpetfish make up the genus Aulostomus of the family Aulostomid

References

"Aulostomus maculatus". FishBase. Ed. Ranier Froese and Daniel Pauly. 10 2005 version. N.p.: FishBase, 2005.

Trumpetfish

Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Syngnathiformes
Family:	Aulostomidae
Genus:	Aulostomus
Species:	A. maculatus
Binomial name
*Aulostomus maculatus* (Valenciennes, 1837)

Triggerfish, (Balistidae)

Fri, 30 Oct 2009 01:02:00 GMT

Triggerfishes are various, often brightly colored fish of the family Balistidae. Often marked by lines and spots, they inhabit warm coastal waters of the Atlantic, Mediterranean and the Indo-Pacific.

Anatomy and appearance

Triggerfish have an oval, highly compressed body. The head is large, terminated in a small but strong- jawed mouth with teeth adapted for crushing shells. The eyes are small, set far back from the mouth, at the top of the head. The anterior dorsal fin is reduced to a set of three spines. The first spine is stout and by far the longest. All three are normally retracted into a groove. The ventral and the posterior dorsal fins are capable of undulating from side to side to provide slow speed movement. The sickle shaped caudal fin is used only to escape predators). The two pelvic fins are overlaid by skin for most of their length and fused to form a single spine, terminated by very short rays, their only external evidence. Gill plates operculum too, although present are not visible, overlaid by the tough skin, covered with rough, rhomboid scales, that forms a stout armor on their body. The only gill opening is a vertical slit, directly above the pectoral fins. This peculiar covering of the gill plates is shared with other members of the Tetradontae order. Each jaw contains a row of four teeth on either side, while the upper jaw contains an additional set of six plate-like pharingeal teeth. As a protection against predators, Triggerfish can erect the first two dorsal spines: The first, (anterior) spine is locked in place by erection of the short second spine, and can be unlocked only by depressing the second, “trigger” spine, hence the family name “Triggerfish”. Adult Triggerfish of the various species found worldwide, range in size from 8 inches to 3 feet long (20 to 90 cm).

Behavior

The rather bizarre anatomy of the triggerfish reflects its diet of slow-moving, bottom dwelling crustaceans, mollusks, sea urchins and other echinoderms, generrally creatures with protective shells and spines. Triggerfish are usually found over hard bottom where such prey occur. Some triggerfish species can be quite aggressive when guarding their eggs. Both Picasso and Titan triggerfish viciously defend their nests against intruders, including scuba divers and snorkelers. Their territory extends in a cone from the nest toward the surface, so swimming upwards can put a diver further into the fishes' territory; a horizontal swim away from the nest site is best when confronted by an angry triggerfish. Unlike the relatively small Picasso triggerfish,the titan triggerfish poses a serious threat to inattentive divers due to its large size and powerful teeth. Triggerfish are notorious bait stealers; rather than swallowing a bait whole, they nibble off small bites of it, making a small, stout hook essential to success in hooking them. Accordingly, the best baits are tough strips of fish skin, squid mantle etc.

Edibility

Triggerfish, at least the Gray Triggerfish (Balistes Carolinensis) found off the east coast of Florida, are excellent table-fare. Their flesh is white, firm and flavorful, with only a few bits of red flesh which may be scraped off easily at the base of the ventral and posterior dorsal fins. Triggerfish should be eaten in the form of skinless fillets; the stout, totally inedible skin may be removed by puncturing the skin with a sharp-pointed knife, and cutting the skin from the inside to avoid having to cut the scales.

Life history

Triggerfish lay their demersal eggs in a small hole dug in the sea bottom. Off Florida, juvenile Triggerfish are found in floating sargassum, where they feed on the small shrimp,crabs and mullusks found there.

Triggerfish

Titan triggerfish (Balistoides viridescens)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Tetraodontiformes
Family:	Balistidae

Clown Triggerfish, (Balistoides conspicillum)

Fri, 30 Oct 2009 01:07:00 GMT

The Clown Triggerfish, Balistoides conspicillum, is a triggerfish from the order Tetraodontiformes. This reef-associated fish is commonly found in the tropical Indo-Pacific

Distribution and habitat

This species is a primarily marine species. This fish is found in Tropical Indo-Pacificcoastal waters from 1-75 metres in depth (3-250 ft). This fish is generally uncommon or rare throughout its range, which includes East Africa to South Africa, through toIndonesia, and all the way to Japan and New Caledonia.

The clown triggerfish is most commonly found around coral reefs. It lives in clear coastal to outer reef habitats. It also occurs in clear, seaward reefs near steep drop-offs.It also resides in the Great Barrier reef.

Anatomy and appearance

The fish can reach up to about 50 cm (20 in) in length. It has strong jaws which can be used to crush and eat sea urchins, crustaceans and hard-shelled mollusks.

This fish has unique coloration. The ventral surface has large, white spots on a dark background, and its dorsal surface has black spots on yellow. There is a vertical, white (slightly yellow) stripe on the caudal fin. The brightly painted yellow mouth may be used to deter potential predators. This fish has a form of camouflage that is, or is similar to,countershading. From below, the white spots look like the surface of the water above it. From above, the fish will blend in more with the coral reef environment.

In the aquarium

Because of its attractive coloration, this fish is one of the most highly prized aquarium fish. Like many other triggerfish, it can require a large aquarium and be aggressive towards other fish. It should not be kept with small fishes. It will also prey on invertebrates in the aquarium. This fish can become tame enough to be hand-fed, however one should beware of the fish's sharp teeth.

References

^ ^a ^b ^c ^d ^e "Balistoides conspicillum". FishBase. Ed. Ranier Froese and Daniel Pauly. Apr 2007 version. N.p.: FishBase, 2007.
^ ^a ^b Dakin, Nick (1992). The Macmillan book of the Marine Aquarium. New York: Macmillan Publishing Company. pp. 177. ISBN 0-02-897108-6.
^ ^a ^b Sanford, Gina (1999). Aquarium Owner's Guide. New York: DK Publishing. pp. 132. ISBN 0-7894-4614-6.

Balistoides conspicillum (TSN 173225). Integrated Taxonomic Information System. Retrieved on 24 January 2006.

Orange Lined Triggerfish, (Balistapus undulatus)

Fri, 30 Oct 2009 01:13:00 GMT

The Orange-lined Triggerfish, Orange-striped Triggerfish or Undulated Triggerfish (Balistapus undulatus) is a triggerfish of the tropical Indo-Pacific area. It is the only member of the genus Balistapus. They reach a maximum size of about 30 cm. They feed on coral, crabs and invertebrates. They are found up to around 50 m deep in tropical waters.

In the Aquarium

Balistapus undulatus is a hardy member of a saltwater aquarium. It however has a reputation as one of the meanest fish in the aquarium trade. Sometimes young individuals will accept tank-mates but an owner should expect this fish to kill most fish and invertebrates that share its aquarium. Serious consideration should therefore be made for keeping this fish alone. The minimum tank size to keep a small fish alone is 50 gallons. It is a slow growing fish, but as it gets older it will likely need a larger aquarium.

Orange-lined Triggerfish

Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Tetraodontiformes
Family:	Balistidae
Genus:	Balistapus Tilesius, 1820
Species:	B. undulatus
Binomial name
*Balistapus undulatus* (Park, 1797)

References

Balistapus undulatus (TSN 173218). Integrated Taxonomic Information System. Retrieved on 12 April 2006.
"Balistapus undulatus". FishBase. Ed. Ranier Froese and Daniel Pauly. April 2006 version. N.p.: FishBase, 2006.

centralpets.com Page on Orange-Lined Triggerfish
advancedaquarist.com Page on Triggerfish

Titan Triggerfish, (Balistoides viridescens)

Fri, 30 Oct 2009 01:19:00 GMT

The Titan Triggerfish, Balistoides viridescens, is the largest of the Triggerfish species and can grow up to 75 cm in length (30 inches). Their range includes reef areas in the Indo-Pacific region, including Australia, Fiji, Thailand, Indonesia, Philippines and the Maldives, also in the Red Sea. The fish is not a pelagic species and generally lives in the flat areas of the reef.

Characteristics

Titan triggerfish are the workers of the reef and often surrounded by other fish feeding from the leftovers.

Titan triggerfish feed on shellfish, urchins, crustaceans and coral. They are the workers of the reef, often being busy turning over rocks, stirring up the sand and biting off pieces of branching coral. This is why one often sees other smaller fish species around it who feed from the left overs.

Titan triggerfish with Orange-lined triggerfish and Moorish Idols at the reef of Fihalhohi, Maldives.

Interaction with humans

The fish can be very aggressive towards divers and snorkellers. Especially during reproduction season it is very territorial and will guard its nest, which it lays in a flat sandy area, vigorously against any intruders. Due to its size and strong teeth it can inflict serious injury. Bites may also beciguatoxic. The Titan Triggerfish will not always bite, but can swim at snorkellers and divers escorting them out of their territory. When the males (most colourful) start swimming in your direction, the best thing to do is swim away backwards kicking your fins as a defence. Failure to do so may result in being bitten. Prior to aggressive action, the fish will often roll onto its side, allowing it a better look at the intruder it perceives at threatening it or its eggs. Divers can look for the fish to perform this rolling action, and take it as a warning, allowing them time to retreat to a safe distance before the fish attacks.

Titan triggerfish

Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Tetraodontiformes
Family:	Balistidae
Genus:	Balistoides
Species:	B. viridescens
Binomial name
*Balistoides viridescens* (Bloch & Schneider, 1801)

References

^ Dive the World. "Diving with Titan Triggerfish". Retrieved 2009-06-14.

Aquarium Fish: Triggerfish

Balistoides viridescens (TSN 173224). Integrated Taxonomic Information System. Retrieved on 24 January 2006.
"Balistoides viridescens". FishBase. Ed. Ranier Froese and Daniel Pauly. 10 2005 version. N.p.: FishBase, 2005.

Squirrelfish, (Holocentridae)

Thu, 29 Oct 2009 08:48:00 GMT

The Holocentridae is a family of ray-finned fish, belonging to the order Beryciformes with the members of the subfamily Holocentrinae typically known as squirrelfish, while the members of Myripristinae typically are known as soldierfish. In Hawaii they are known as menpachi.

They are found in tropical parts of the Indian, Pacific and Atlantic Oceans, with the greatest species diversity near reefs in theIndo-Pacific. Most are found at depths from the shoreline to 100 m (330 ft), but some, notably the members of the genusOstichthys, are generally found far deeper. Being largely or entirely nocturnal, they have relatively large eyes. During the day they typically remain hidden in crevices, caves, or under ledges. Red and silvery colours dominate. The preopercle spines (near thegill-opening) of the members of the subfamily Holocentrinae are venomous, and can give painful wounds. Most have a maximum length of 15-35 cm (6-14 in), but Sargocentron iota barely reaches 8 cm (3 in), and S. spiniferum and Holocentrus adscensioniscan reach more than 50 cm (20 in). The squirrelfishes mainly feed on small fishes and benthic invertebrates, while the soldierfishes typically feed on zooplankton. The larvae are pelagic, unlike the adults, and can be found far out to sea.

Crown of Thorns Starfish, (Acanthaster planci)

Thu, 29 Oct 2009 09:07:00 GMT

The Crown-of-Thorns Starfish (Acanthaster planci) is a large nocturnal sea star that preys upon coral polyps. The Crown-of-Thorns receives its name from venomous thorn-like spines that cover its body.

The Crown-of-Thorns is endemic to tropical coral reefs in the Red Sea, the Indian Ocean, and the Pacific Ocean. As solitary animals, they feed alone and maintain constant distance between themselves and other members of their species.

The Crown-of-Thorns is the second largest sea star in the world. Only the Giant Sunstar is larger.

Physical description and physiology

Crown-of-thorns starfish

The Crown-of-Thorns can grow from the size of a grain of sand to the size of a dinner plate. An exceptionally large crown of thorns can grow to be the size of a school bus tire.

Like other sea stars, the Crown-of-Thorns is capable of limb regeneration, and can regrow to full size from a severed limb.

The sharp spines on the sides of the starfish's limbs resemble thorns and create a crown-like shape, giving the creature its name. These thorns are very sharp and are capable of piercing through standard wetsuits and other clothing. They are also venomous.

Venom

The Crown-of-Thorns produces a neurotoxin which can be released through its spines. Not only are the wounds themselves serious, but the neurotoxin can cause a sharp stinging pain that can last for hours, as well as nausea and vomiting. Frequently, the area around the wound turns a dark blue (erythema) and begins to swell (edema). Swelling may persist for days to weeks. The spine(s) may break and remnants may become embedded inside the skin. This can lead to infection, and increased toxicity.

Some divers kill these predators by injecting the starfish's own stomach acid into each of their many legs.

Behaviour

The Crown-of-Thorns is a corallivore, a carnivorous predator that preys on reef coral polyps. They climb onto reef structures, and then extrude their stomach onto the coral. This releases digestive enzymes that allow the starfish to absorb nutrients from the liquefied coral tissue. The Crown-of-Thorns also preys on brittle stars in a similar fashion.

They are voracious predators... An individual starfish can consume up to 6 square metres (65 sq ft) of living coral reef per year.

During times of food shortage the Crown-of-Thorns can survive on energy reserves for over six months.

Natural predators

The natural defences of the adult starfish make it an unattractive target for other reef predators. Venom and sharp pointy parts aside, the Giant Triton (a mollusc) and theharlequin shrimp attack and feed on Crown-of-Thorns starfish. Some large reef fish, particularly Humphead wrasse, may also prey on the starfish.

Sea star larvae are planktonic, so the major population control of the species comes from planktonic predation of junior species members.

In an interesting reversal, a large solitary coral polyp of the genus Pseudocorynactis has been observed attacking, and then wholly ingesting a crown-of-thorns starfish of similar size.

Decline in predator populations (through overharvesting, habitat destruction) has also been offered as an explanation for increasing outbreaks of Crown-of-Thorns starfish.

Ecological impact

Crown-ofThorns amongst coral reef, off the coast of Madagascar

The Crown-of-Thorns starfish has gained notoriety as a threat to the coral reef ecosystem, particularly in the Great Barrier Reef off the coast of Australia. Overpopulation of Crown-of-Thorns has been blamed for widespread reef destruction. Birkeland (1985) describes the starfish as one of the most influential species in the diverse biotic communities that make up tropical coral reefs.

Some ecologists point out that the starfish has an important and active role in maintaining coral reef biodiversity, driving ecological succession. Before overpopulation became a significant issue, Crown-of-Thorns kept the fast growing coral from overpowering the slower growing coral.

Other factors negatively affecting the reef ecosystem, such as coral bleaching or Black band disease, mean that outbreaks of the Crown-of-Thorns can now cause permanent and devastating damage. Increasing outbreaks are also thought to be caused by possible environmental pollution triggers. Algal blooms caused by agricultural run-off may supply predators of Crown-of-Starfish larvae with plentiful alternative food sources. These explanations may also explain why massive outbreaks seemingly appearing out of nowhere, with no previous indication of an increasing population at the affected site.

Crown of thorns starfish in French Polynesia

Population control

Population numbers for the Crown-of-Thorns have been increasing since the 1970s. However, historic records distribution patterns and numbers are hard to come by, as SCUBA technology, necessary to conduct population censuses, had only been developed in the previous few decades.

To prevent overpopulation of Crown-of-Thorns causing widespread destruction to coral reef habitats, humans have implemented a variety of control measures.

Injecting sodium bisulphate into the starfish is the most efficient measure in practice. Sodium bisulphate is deadly to Crown-of-Thorns, but it does not harm the surrounding reef and oceanic ecosystems.

When under stress The Crown-Of-Thorns releases spores which can create outbreaks, and if it is dismembered the crown-of-thorns can re-generate from each body part, creating more sea stars. Thus controlling the Crown-Of-Thorns is difficult and much care is required.

Taxonomy

The Crown-of-Thorns Starfish has generally been considered as a single widespread species: A. planci. However, results from DNA analyses published in September 2008 suggest that the crown-of-thorns starfish is actually constituted of four species, with distinct distributions (Red Sea, Pacific, Northern and Southern Indian Ocean).

Differences between these putative species in behaviour, diet, or habitat may be important for the design of appropriate reef conservation strategies.

References

^ Pierre Madl (1998). "Acanthaster planci (An overview of the crown of thorns starfish)". Retrieved 2006-08-28.
^ Randall JE, SM Mead, APL Sanders (1978). "Food habits of the giant humphead wrasse cheilinus undulatus".
^ A.R. Bos, G.S. Gumanao & F.N. Salac (2008-02-09). "A newly discovered predator of the crown-of-thorns starfish".
^ Larry Zetlin.. Predators of the Great Barrier Reef. [TV-Special]. Queensland, Australia: Gulliver Media Australia.
^ "Controlling Crown-of Thorns Starfish". Great Barrier Reef Marine Park Authority. April 1995. Retrieved 15 December 2008.
^ Vogler C, Benzie J, Lessios H, Barber P, Wörheide G (2008-09-29). "A threat to coral reefs multiplied? Four species of crown-of-thorns starfish". Biology Letters (Royal Society).doi:10.1098/rsbl.2008.0454. Retrieved 2008-10-14.
^ "Coral-killing starfish turns out to be four species, not one". Yahoo! News. AFP. 2008-09-30. Retrieved 2008-10-14.

Crown-of-thorns starfish

On a reef in Fiji, 2005.
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Asteroidea
Order:	Valvatida
Family:	Acanthasteridae
Genus:	Acanthaster Gervais, 1841
Species:	A. planci
Binomial name
*Acanthaster planci* (Linnaeus, 1758)

Surgeonfish, (Acanthuridae)

Thu, 29 Oct 2009 09:24:00 GMT

Acanthuridae ("thorn tail") is the family of surgeonfishes, tang, and unicornfishes. The family includes about 80 species in six genera, all of which are marine fish living in tropical seas, usually around coral reefs. Many of the species are brightly colored and popular for aquaria.

The distinctive characteristic of the family is the spines, one or more on either side of the tail, which are dangerously sharp. Both the dorsal and anal fins are large, extending for most of the length of the body. The small mouths have a single row of teeth used for grazing on algae.

Most species are relatively small and have a maximum length of 15-40 cm (6-16 in), but some members of the genus Acanthurus, some members of the genus Prionurus, and most members of the genus Naso can grow larger, with the whitemargin unicornfish (N. annulatus), the largest species in the family, reaching a length of up to a meter (3,3 ft). These fishes can grow quickly in aquariums so it is advisable to check the average growth size and suitability before adding to a marine aquarium.

Species

Achilles tang, Acanthurus achilles

Blue tang, Acanthurus coeruleus

Eyestripe surgeonfish,Acanthurus dussumieri

Powderblue surgeonfish,Acanthurus leucosternon

Doubleband surgeonfish,Acanthurus tennenti

Kole Tang, Ctenochaetus strigosus

Elongate unicornfish, Naso lopezi

Bluespine unicornfish, Naso unicornis

Red Sea sailfin tang, Zebrasoma desjardinii

Orangespot surgeonfish,Acanthurus olivaceus, is being cleaned by two Hawaiian cleaner wrasse, Labroides phthirophagus

Genus Acanthurus
- Achilles tang, Acanthurus achilles Shaw, 1803.
- Whitefin surgeonfish, Acanthurus albipectoralis Allen & Ayling, 1987.
- Orange-socket surgeonfish, Acanthurus auranticavus Randall, 1956.
- Ocean surgeon, Acanthurus bahianus Castelnau, 1855.
- Black-spot surgeonfish, Acanthurus bariene Lesson, 1831.
- Ringtail surgeonfish, Acanthurus blochii Valenciennes, 1835.
- Doctorfish tang, Acanthurus chirurgus (Bloch, 1787).
- Chronixis surgeonfish, Acanthurus chronixis Randall, 1960.
- Atlantic Blue tang surgeonfish, Acanthurus coeruleus Bloch & Schneider, 1801.
- Eyestripe surgeonfish, Acanthurus dussumieri Valenciennes, 1835.
- Fowler's surgeonfish, Acanthurus fowleri de Beaufort, 1951.
- Black surgeonfish, Acanthurus gahhm (Forsskål, 1775).
- Finelined surgeonfish, Acanthurus grammoptilus Richardson, 1843.
- Whitespotted surgeonfish, Acanthurus guttatus Forster, 1801.
- Japan surgeonfish, Acanthurus japonicus (Schmidt, 1931).
- Palelipped surgeonfish, Acanthurus leucocheilus Herre, 1927.
- Whitebar surgeonfish, Acanthurus leucopareius (Jenkins, 1903).
- Powderblue surgeonfish, Acanthurus leucosternon Bennett, 1833.
- Lined surgeonfish, Acanthurus lineatus (Linnaeus, 1758).
- White-freckled surgeonfish, Acanthurus maculiceps] (Ahl, 1923).
- Elongate surgeonfish, Acanthurus mata (Cuvier, 1829).
- Monrovia doctorfish, Acanthurus monroviae Steindachner, 1876.
- Whitecheek surgeonfish, Acanthurus nigricans (Linnaeus, 1758).
- Epaulette surgeonfish, Acanthurus nigricauda Duncker & Mohr, 1929.
- Brown surgeonfish, Acanthurus nigrofuscus (Forsskål, 1775).
- Bluelined surgeonfish, Acanthurus nigroris Valenciennes, 1835.
- Bluelined surgeon, Acanthurus nubilus (Fowler & Bean, 1929).
- Orangespot surgeonfish, Acanthurus olivaceus Bloch & Schneider, 1801.
- Black-barred surgeonfish, Acanthurus polyzona (Bleeker, 1868).
- Chocolate surgeonfish, Acanthurus pyroferus Kittlitz, 1834.
- Gulf surgeonfish, Acanthurus randalli Briggs & Caldwell, 1957.
- Acanthurus reversus Randall & Earle, 1999.
- Sohal surgeonfish, Acanthurus sohal (Forsskål, 1775).
- Doubleband surgeonfish, Acanthurus tennentii Günther, 1861.
- Thompson's surgeonfish, Acanthurus thompsoni (Fowler, 1923).
- Convict surgeonfish, Acanthurus triostegus (Linnaeus, 1758).
- Indian Ocean mimic surgeonfish, Acanthurus tristis Randall, 1993.
- Yellowfin surgeonfish, Acanthurus xanthopterus Valenciennes, 1835.
Genus Ctenochaetus
- Twospot surgeonfish, Ctenochaetus binotatus Randall, 1955.
- Ctenochaetus cyanocheilus Randall & Clements, 2001.
- Ctenochaetus flavicauda Fowler, 1938.
- Striped-fin surgeonfish, Ctenochaetus marginatus (Valenciennes, 1835).
- Striated surgeonfish, Ctenochaetus striatus (Quoy & Gaimard, 1825).
- Kole Tang, Ctenochaetus strigosus (Bennett, 1828).
- Tomini surgeonfish, Ctenochaetus tominiensis Randall, 1955.
- Ctenochaetus truncatus Randall & Clements, 2001.
Genus Naso
- Whitemargin unicornfish, Naso annulatus (Quoy & Gaimard, 1825).
- Humpback unicornfish, Naso brachycentron (Valenciennes, 1835).
- Spotted unicornfish, Naso brevirostris (Cuvier, 1829).
- Naso caeruleacauda Randall, 1994.
- Gray unicornfish, Naso caesius Randall & Bell, 1992.
- Elegant unicornfish, Naso elegans (Rüppell, 1829).
- Horseface unicornfish, Naso fageni Morrow, 1954.
- Sleek unicornfish, Naso hexacanthus (Bleeker, 1855).
- Orangespine unicornfish, Naso lituratus (Forster, 1801).
- Elongate unicornfish, Naso lopezi Herre, 1927.
- Naso maculatus Randall & Struhsaker, 1981.
- Squarenose unicornfish, Naso mcdadei Johnson, 2002.
- Slender unicorn, Naso minor (Smith, 1966).
- Naso reticulatus Randall, 2001.
- Oneknife unicornfish, Naso thynnoides (Cuvier, 1829).
- Bulbnose unicornfish, Naso tonganus (Valenciennes, 1835).
- Humpnose unicornfish, Naso tuberosus Lacépède, 1801.
- Bluespine unicornfish, Naso unicornis (Forsskål, 1775).
- Bignose unicornfish, Naso vlamingii (Valenciennes, 1835).
Genus Paracanthurus
- Palette surgeonfish, Paracanthurus hepatus (Linnaeus, 1766).
Genus Prionurus
- Biafra doctorfish, Prionurus biafraensis (Blache & Rossignol, 1961).
- Prionurus chrysurus Randall, 2001.
- Razor surgeonfish, Prionurus laticlavius (Valenciennes, 1846).
- Yellowspotted sawtail, Prionurus maculatus (Randall & Struhsaker, 1981).
- Sixplate sawtail, Prionurus microlepidotus Lacépède, 1804.
- Yellowtail surgeonfish, Prionurus punctatus Gill, 1862.
- Scalpel sawtail, Prionurus scalprum Valenciennes, 1835.
Genus Zebrasoma
- Red Sea sailfin tang, Zebrasoma desjardinii (Bennett, 1836).
- Yellow tang, Zebrasoma flavescens (Bennett, 1828).
- Spotted tang, Zebrasoma gemmatum (Valenciennes, 1835).
- Longnose surgeonfish, Zebrasoma rostratum (Günther, 1875).
- Twotone tang, Zebrasoma scopas (Cuvier, 1829).
- Sailfin tang, Zebrasoma veliferum (Bloch, 1795).
- Yellowtail tang, Zebrasoma xanthurum (Blyth, 1852).

Sweetlips, (Plectorhinchus)

Thu, 29 Oct 2009 10:08:00 GMT

Sweetlips Fossil range: Miocene to Present

Harlequin sweetlips,Plectorhinchus chaetodonoides
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Haemulidae
Species
See text.
Synonyms
Sweetlips

The sweetlips, Plectorhinchus, are a genera, in the family Haemulidae, with 35 species found in fresh, brackish and salt waters. These fish have big fleshy lips and tend to live on coral reefs in the Indo-Pacific in small groups or pairs. They will often associate with other fishes of similar species, and it is not unusual to see several species of sweetlips all swimming together. They are usually seen in clusters in nooks and crannies or under overhangs. Not until night falls do they venture from their shelters to seek out their bottom-dwelling invertebrate prey, such as bristle worms or shrimps and small crabs.

Sweetlips' colouring and patterning changes throughout their lives. Adult ribboned sweetlips (Plectorhinchus polytaenia) develop increasing stripes with age. Juvenile sweetlips generally look quite different to the adults and often live a solitary life on shallower reef sections than those where the adults are found. Juveniles may be banded or spotted and are usually a completely different color to the adult. Small juveniles have a strange undulating way of swimming, possibly mimicking poisonous flatworms as a means of camouflage

Species

Plectorhinchus albovittatus, Two-striped sweetlips (Rüppell, 1838)
Plectorhinchus celebicus, Celebes sweetlips Bleeker, 1873
Plectorhinchus ceylonensis, Sri Lanka sweetlips (Smith, 1956)
Plectorhinchus chaetodonoides, Harlequin sweetlips Lacepède, 1801
Plectorhinchus chrysotaenia, Yellow-striped sweetlips (Bleeker, 1855)
Plectorhinchus chubbi, Dusky rubberlip (Regan, 1919)
Plectorhinchus cinctus, Crescent sweetlips (Temminck & Schlegel, 1843)
Plectorhinchus diagrammus, Striped sweetlips (Linnaeus, 1758)
Plectorhinchus faetela (Forsskål, 1775)
Plectorhinchus flavomaculatus, Lemon sweetlip (Cuvier, 1830)
Plectorhinchus gaterinoides, Lined sweetlips (Smith, 1962)
Plectorhinchus gaterinus, Blackspotted rubberlip (Forsskål, 1775)
Plectorhinchus gibbosus, Harry hotlips (Hombron & Jacquinot, 1853)
Plectorhinchus harrawayi (Smith, 1952)
Plectorhinchus lessonii, Lesson's thicklip (Cuvier, 1830)
Plectorhinchus lineatus, Yellowbanded sweetlips (Linnaeus, 1758)
Plectorhinchus macrolepis, Biglip grunt (Boulenger, 1899)
Plectorhinchus macrospilus Satapoomin & Randall, 2000
Plectorhinchus mediterraneus, Rubberlip grunt (Guichenot, 1850)
Plectorhinchus multivittatus, Many-lined sweetlips (Macleay, 1878)
Plectorhinchus nigrus (Cuvier, 1830)
Plectorhinchus obscurus, Giant sweetlips (Günther, 1872)
Plectorhinchus orientalis, Oriental sweetlips (Bloch, 1793)
Plectorhinchus paulayi, Zebra sweetlip Steindachner, 1895
Plectorhinchus pictus, Trout sweetlips (Tortonese, 1936)
Plectorhinchus picus, Painted sweetlip (Cuvier, 1830)
Plectorhinchus plagiodesmus, Barred rubberlip Fowler, 1935
Plectorhinchus playfairi, Whitebarred rubberlip (Pellegrin, 1914)
Plectorhinchus polytaenia, Ribboned sweetlips (Bleeker, 1852)
Plectorhinchus punctatissimus (Playfair, 1868)
Plectorhinchus schotaf, Minstrel sweetlip (Forsskål, 1775)
Plectorhinchus sordidus, Sordid rubberlip (Klunzinger, 1870)
Plectorhinchus umbrinus (Klunzinger, 1870)
Plectorhinchus unicolor (Macleay, 1883)
Plectorhinchus vittatus, Oriental Sweetlips (Linnaeus, 1758)

Sweetlips, (Plectorhinchus)

Thu, 29 Oct 2009 10:08:00 GMT

Sweetlips Fossil range: Miocene to Present^[1]

Harlequin sweetlips,Plectorhinchus chaetodonoides
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Haemulidae
Species
See text.
Synonyms
Sweetlips

Species

Plectorhinchus albovittatus, Two-striped sweetlips (Rüppell, 1838)
Plectorhinchus celebicus, Celebes sweetlips Bleeker, 1873
Plectorhinchus ceylonensis, Sri Lanka sweetlips (Smith, 1956)
Plectorhinchus chaetodonoides, Harlequin sweetlips Lacepède, 1801
Plectorhinchus chrysotaenia, Yellow-striped sweetlips (Bleeker, 1855)
Plectorhinchus chubbi, Dusky rubberlip (Regan, 1919)
Plectorhinchus cinctus, Crescent sweetlips (Temminck & Schlegel, 1843)
Plectorhinchus diagrammus, Striped sweetlips (Linnaeus, 1758)
Plectorhinchus faetela (Forsskål, 1775)
Plectorhinchus flavomaculatus, Lemon sweetlip (Cuvier, 1830)
Plectorhinchus gaterinoides, Lined sweetlips (Smith, 1962)
Plectorhinchus gaterinus, Blackspotted rubberlip (Forsskål, 1775)
Plectorhinchus gibbosus, Harry hotlips (Hombron & Jacquinot, 1853)
Plectorhinchus harrawayi (Smith, 1952)
Plectorhinchus lessonii, Lesson's thicklip (Cuvier, 1830)
Plectorhinchus lineatus, Yellowbanded sweetlips (Linnaeus, 1758)
Plectorhinchus macrolepis, Biglip grunt (Boulenger, 1899)
Plectorhinchus macrospilus Satapoomin & Randall, 2000
Plectorhinchus mediterraneus, Rubberlip grunt (Guichenot, 1850)
Plectorhinchus multivittatus, Many-lined sweetlips (Macleay, 1878)
Plectorhinchus nigrus (Cuvier, 1830)
Plectorhinchus obscurus, Giant sweetlips (Günther, 1872)
Plectorhinchus orientalis, Oriental sweetlips (Bloch, 1793)
Plectorhinchus paulayi, Zebra sweetlip Steindachner, 1895
Plectorhinchus pictus, Trout sweetlips (Tortonese, 1936)
Plectorhinchus picus, Painted sweetlip (Cuvier, 1830)
Plectorhinchus plagiodesmus, Barred rubberlip Fowler, 1935
Plectorhinchus playfairi, Whitebarred rubberlip (Pellegrin, 1914)
Plectorhinchus polytaenia, Ribboned sweetlips (Bleeker, 1852)
Plectorhinchus punctatissimus (Playfair, 1868)
Plectorhinchus schotaf, Minstrel sweetlip (Forsskål, 1775)
Plectorhinchus sordidus, Sordid rubberlip (Klunzinger, 1870)
Plectorhinchus umbrinus (Klunzinger, 1870)
Plectorhinchus unicolor (Macleay, 1883)
Plectorhinchus vittatus, Oriental Sweetlips (Linnaeus, 1758)

Two Line Spinecheek, (Scolopsis bilineatus)

Wed, 07 Oct 2009 01:55:00 GMT

I don't have any information on this species - sorry. If you would like to add content to this page or photos please email it to me and i'll see it goes up.....

Twin Spot Snapper, (Lutjanus biguttatus)

Tue, 06 Oct 2009 06:29:00 GMT

Environment

Reef-associated; marine; depth range 3 - 36 m

Climate / Range

Tropical; 23°N - 14°S, 71°E - 165°E

Indo-Pacific: mainly the Indo-Australian Archipelago from the Solomon Islands to Sumatra, and from off Cape York Peninsula, Australia, northward to the Philippines; also occurring in the central and eastern Indian Ocean as far west as Maldives.

Short description

Dorsal spines (total): 11; Dorsal soft rays (total): 12; Anal spines: 3; Anal soft rays: 8. Snout profile low, sloping very gently. Preorbital bone narrow, its width less than half of eye diameter. Preopercular notch and knob poorly developed. Scale rows on back rising obliquely above lateral line. Generally dark brown of the upper part of the head and body with a broad white horizontal band immediately below. The lower part of the head and body dusky brown with a suffusion of yellow. A pair of white spots is on the back just below the dorsal fin base.

Inhabits coral reefs and outer reef slopes. Sometimes in large schools of more than 100 individuals. Often solitary. Feeds mainly on small fishes and crustaceans. Generally uncommon.

Fish Facts

Frogfish (Antennariidae)

Features

Mimicry and camouflage

Movement

Hunting

Reproduction

Species

References

Hermit Crabs, (Paguroidea)

Development and reproduction

Hawksbill Turtle, (Eretmochelys imbricata)

Ecology and life history

Habitat

Feeding ecology

[edit]Life history

Evolutionary history

Etymology and taxonomic history

Conservation

See also

References

Trumpetfish, (Aulostomus maculatus)

Habitat

Description

References

Triggerfish, (Balistidae)

Anatomy and appearance

Behavior

Edibility

Life history

Clown Triggerfish, (Balistoides conspicillum)

Distribution and habitat

Anatomy and appearance

In the aquarium

References

Orange Lined Triggerfish, (Balistapus undulatus)

In the Aquarium

References

Titan Triggerfish, (Balistoides viridescens)

Characteristics

Interaction with humans

References

Squirrelfish, (Holocentridae)

Crown of Thorns Starfish, (Acanthaster planci)

Physical description and physiology

Venom

Behaviour

Natural predators

Ecological impact

Population control

Taxonomy

References

Surgeonfish, (Acanthuridae)

Species

Sweetlips, (Plectorhinchus)

Species

Sweetlips, (Plectorhinchus)

Species

Two Line Spinecheek, (Scolopsis bilineatus)

Twin Spot Snapper, (Lutjanus biguttatus)