Jan 29, 2011

Squirrelfish

The common squirrelfish, or Holocentrus adscensionis, gets its common name from its big squirrel-like eyes.  This species of squirrelfish can be identified by its yellow front dorsal fin.  The back part of the dorsal fin is elongated and almost translucent.  Its body is a reddish color with light silvery stripes and occasional white patches.  The common squirrelfish is the largest species of squirrelfishes reaching a maximum of 16 inches and averaging about eight to ten inches.

This squirrelfish was getting a cleaning from a cleaner shrimp when I interupted 
All squirrelfish are bony fish and belong to the family Holocentridae, or squirrelfishes.  This family is characterized by a reddish body, "squirrel-like" eyes, and a long, extended rear dorsal fin that is said to resemble a squirrel's tail.  Its members also all have thin, white, and occasionally yellow-gold, body stripes. Many species of squirrelfish produce sounds used for inter- and intra- species communication.  They are territorial animals and often can be seen chasing off other squirrelfish or giving sounds that tell potential intruders to stay out.

The common squirrelfish is a tropical shallow water reef fish that can be found from North Carolina to Brazil, and along the warm waters of western Africa. Most squirrelfish are nocturnal feeders but can often be seen hiding on the reef during the day.  When nightfall comes, the common squirrelfish migrates away from the reef to forage for crabs and shrimp on close-by sand flats and grass beds.  In turn, many other larger fish prey upon the common squirrelfish such as dolphinfish, mutton snapper, yellowfin tuna, and even sea birds if they can get their hands on them.  This specific species spawns year round in tropical waters, but it is restricted to reproducing during the summer months in places like North Carolina and southern South America.

References: "Squirrelfish." Florida Museum of Natural History. Web. 29 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/Squirrelfish/Squirrelfish.html>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 236-239. Print.


Jan 27, 2011

Giant Anemone

Notice the Yellowline Arrow Crab below the Anemone
The giant caribbean sea anemone is one of the most beautiful reef organisms.  They are the largest of the anemones, growing to be about six to 12 inches across.  The giant anemone can be identified by its long tenticles with enlarged tips.  These anemones come in a variety of colors including white, blue, green, yellow, and brown. Often the tips of the anemone are different colors from the body; they may be pink, lavender, yellow, chartreuse, or white.  The tips, however, do not always differ in color, as evident by the giant anemone to the left.

There is a common misconception that anemones are either plants or corals. They are, however, neither.  Corals and anemones are closely related though, belonging to the same phylum Cnidaria.  Cnidarians have a simple structure consisting of a cup-shaped body, a central opening that is both the mouth and anus, and numerous tenticles that surround the central opening.  Cnidarians may live attached to substrate or as free swimming organisms.  When the animal is attached to substrate it is called a polyp, and if it is free swimming it is called a medusa.  Often a cnidarian's life cycle consists of both a polyp and a medusa stage.  Additionally, cnidarians may also live in colonies or as separate individuals.  Another characteristic of cnidarians is that they all have stinging capsules called nematocysts that are used for protection and aid in capturing food.

The giant anemone's scientific name is Condylactis gigantea and it obviously belongs to the order Actiniaria, or sea anemones.  All members of the order Actiniaria are individual animals that are attatched to some sort of substrate.  They all have long tentacles with nematocysts that help capture their prey and a slit-like mouth in the center of the body that engulfs the food once it is passed down.  Anemones can move, but they do so only when necessary and it is a very, very slow process.  Also, anemones are often involved in symbiotic relationships with many different reef creatures including fish, shrimp, and crabs.

The giant anemone can be found throughout the tropical waters of the Atlantic.  They are most common in south Florida, throughout the Caribbean, and Bermuda.  Their diet consists of small particulate matter and small organisms that come into contact with their stinging nematocysts.  Like all anemones, this species forms many different symbiotic relationships with reef creatures.  The most common of which is with cleaner shrimps, arrow crabs, and juvenile wrasses.  Zooxanthellae also form a symbiotic relationship with this anemone and provide essential nutrients to its partner.

These anemones can reproduce either sexually or asexually.  They also have the potential to be either dioecious or hermaphroditic.  No matter the process used for reproduction, all methods lead to embryos that hatch into larvae.  The medusa larvae then settle onto a suitable substrate where they attach and begin to grown into adult giant anemones.

References: Humann, Paul, and Ned Deloach. Reef Creature: Identification : Florida, Caribbean, Bahamas. Jacksonville: New World Publ, 1996. 66, 90-91. Print.; Zahra, Marianna. "Giant Caribbean Sea Anemone (Condylactis Gigantea)." Octopus, Squid, Cuttlefish, and Nautilus - The Cephalopod Page. Web. 27 Jan. 2011. <http://www.thecephalopodpage.org/MarineInvertebrateZoology/Condylactisgigantea.html>.

Jan 26, 2011

Spotted Trunkfish

Bizarre is one of the first words that comes to mind when describing the spotted trunkfish.  Lactophyrs bicaudalis can be identified by its white color and dark spots that cover its entire body.  This fish also has a white border around its mouth that helps to separate it from other trunkfish.  Another unique aspect to the spotted trunkfish are two spines in front of the anal fin.  This fish species is commonly grows to be between six and 12 inches, but can reach a maximum length of 16 inches.

A bizarre looking Spotted Trunkfish
The spotted trunkfish is a bony fish that belongs to the family Ostraciidae, or boxfishes.  All boxfishes have a triangular, bony skeleton that serves as armor, small mouths, and broom-like tails.  The family itself is divided into two groups: cowfishes and trunkfishes.  The two groups are very similar, the only difference being cowfishes have spines over the eyes where trunkfishes do not.  Both groups swim mainly using their pectoral and dorsal fins while saving the anal fin for faster movements.

This species of trunkfish is found along the Atlantic coast from Florida, through the Caribbean, and down to Brazil.  It is also found in the western Gulf of Mexico.  The spotted trunkfish is a shallow water reef fish that usually resides under ledges and in protected areas.  This fish consumes a wide variety of food items from small crustaceans, molluscs, algae, to echinoderms.  The spotted trunkfish is poisonous if consumed and its toxin has the ability to kill an adult nurse shark.  The poison may also be used to kill prey when feeding.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 378, 392-393. Print.; "Spotted Trunkfish." Fish Base. http://www.fishbase.org/summary/speciessummary.php?id=4286
   

Green Turtle

Chelonia mydas, or the green turtle, is common marine reptile in tropical waters.  Their common names do not come from their color, but rather the color of their fatty tissue.  They generally have yellowish brown to dark brown shells mixed with shades of olive.  Unlike the loggerhead turtle, the green turtle's first costal plate does not touch the nuchal (see the loggerhead post for explanation of costal and nuchal plates).  Additionally, green turtles have two small plates between the eyes which help separate them from hawksbill turtles who have the same shell pattern.  Although green turtles do not get as large as loggerhead turtles, they can still reach four feet in length and between 250-450 pounds.

These organisms belong to the phylum Chordata and are in the class Reptilia.  All reptiles breath air, lay eggs, have scales, and are ectotherms.  Obviously, they also belong to the order Testudines, or turtles.  This order is characterized by a hard shell that surrounds the body of the organism.  The shell is composed of two main parts: the carapace, the hard top of the shell, and the plastron, or bottom shell.  Another part of the shell called the bridge connects the two main parts.

An averaged sized Green Turtle
Like loggerhead turtles, green sea turtles are found throughout the world's tropical waters.  The various life stages of these marine turtles occupies inshore bays, lagoons, estuaries, offshore reefs, and even the open ocean.  Adults can often be found grazing on reefs or resting under reef ledges.  Green turtles start are primarily herbivores that feed on seagrasses and algae.  From time to time, however, green turtles love to munch on a delicious jellyfish or crustacean.

Like all sea turtles, their life cycle begins on a beach.  After adult green turtles copulate out at sea, females crawl onto sandy beaches at night to lay their eggs.  After a 60 day gestation period, roughly 110 babies hatch and crawl back to the ocean.  The juvenile turtles then take to the ocean currents where they end up in the Azores and Canary Islands.  After reaching sexual maturity, green turtles return to the same reefs and beaches where their parents spawn and lay their eggs; repeating the same process.

The green sea turtle is listed as endangered by the United States Fish and Wildlife Service.  This turtle is highly prized for its shell and in many other countries its meat and eggs.  Up until 1974 there was a green turtle fishery in Florida as well as harvesting their eggs.  Green sea turtles face additional human problems including habitat degredation, boat colisions, marine garbage, entangelment, and bycatch.  Shrimp trawlers account for the majority of accidental green turtle deaths.  Since it takes more than 20 years for these turtles to reach sexual maturity, even a little environmental stress carries a long way.  Hopefully under the protection of the Endangered Species Act and the requirement of the federal government to establish a recovery plan for endangered species, one day green turtles will again be numerous on the reefs of Florida, the Caribbean, and the world.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 481. Print.; "Green Turtle." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 26 Jan. 2011. <http://www.sms.si.edu/irlspec/chelon_mydas.htm>.

Jan 25, 2011

Highhat

A small adult Highhat hiding beneath a reef ledge
Highhats are a reef fish species that can easily be identified by their black and white striped bodies and their mostly black, elongated dorsal fin. Additionally, the pectoral, anal, and tail fins are completely black. highhats change shape and color dramatically from the juvenile to adult life stages. The juvenile stage is characterized by an extremely long dorsal fin, almost two to three times longer than the adult stage. Older juveniles also have an oval marking between the eyes.  Adult highhats are anywhere between five and eight inches long.

The scientific name for the highhat is Pareques acuminatus and they belong to the family Sciaenidae, or drums and croakers.  The common family names are derived from their ability to vibrate muscles surrounding their swim bladder to produce a low-pitched sound.  Highhats have a large distribution and can be found from North Carolina, through Florida, the Caribbean, Gulf of Mexico, and down to Brazil.  This fish species is found on nearshore and offshore reefs ranging from 15 to 75 feet.  Highhats are nocturnal feeders mainly consuming small invertebrates, crustaceans, and fish.  In the day, they congregate under reef ledges and at the front of caves.  The most interesting aspect of the Highhat is its shape and coloration.  Its black and white pattern is by no mistake.  The dark stripes on the highhat are disruptive markings that serve to hide the eyes and confuse predators and prey.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 412-413. Print.
 


Spotted Moray Eel

Similar to the Green Moray, the Spotted Moray is much smaller
The spotted moray eel is a true eel (Anguilliform) and a close relative to the green moray.  This eel is characterized by a white to yellow body covered in dark blotches.  Like the green moray eel, their dorsal and anal fins are fused together to form a single continuous fin that starts behind the head and ends midway down the belly.  Additionally, they have a protective mucus coat around their bodies.  The spotted moray eel is much smaller than the green moray, only reaching an average length of one and a half to three feet.

The spotted moray's scientific name is Gymnothorax moringa, and like all eels, they belong to the class Ostiecthyes, or bony fishes.  The range of the spotted moray stretches from the coast of North Carolina, through the Caribbean, along the Gulf of Mexico, and down to Brazil.  This eel is commonly found sticking out of nearshore or offshore reef holes or underneath rockpiles.  Unlike the solely nocturnal green moray, the spotted moray forages throughout the day and night.  Its diet consists of mostly small crustaceans and reef fish.  Like the green moray, divers are often threatened by these creatures since they continuously open and close their mouths.  This is not a sign of aggression, but rather a behavior for moving water over their gills.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 424-425. Print.

Jan 21, 2011

Lemon Shark

Negaprion brevirostris, or the lemon shark, gets its common name from its yellowish brown color. The defining features of this shark are its short, blunt snout and two dorsal fins of nearly equal size. Additionally, the top portion of its tail is much larger than the the lower.  Adult lemon sharks are generally five to eight feet, but they can reach as large as 11 feet.

Lemon sharks are cartilaginous fishes, belonging to the class Chondrichthyes.  Additionally, lemon sharks belong to the family Carcharhinidae, or requiem sharks.  This family of sharks is characterized by pointed noses, a pit at the base of the tail, the fifth gill slit above the front of the pectoral fin, two dorsal fins, and the presence of blade-like teeth with a single cusp.  Generally, the position of the first dorsal fin in respect to the pectoral fins can determine the species of requiem sharks.  For lemons, the dorsal fin starts above the posterior edge of the pectoral fin.

This species of shark can be found along almost the entire eastern seaboard of the United States, throughout the Caribbean, Gulf of Mexico, and down to Brazil.  They can also be found in the Pacific along the western coast of Mexico, the Sea of Cortez, and even down to Ecuador.  Lemon sharks are an inshore to offshore species inhabiting lagoons, bays, mangrove systems, shallow water reefs, and deeper continental shelves.  They are generally found above 100 feet, but Lemons can inhabit depths down to 300 feet.

Lemon sharks feed on many different marine organisms.  They generally feed on bony fish, stingrays, eaglerays, guitarfish, and crustaceans.  As adults, they have very few predators, but the juvenile lemon sharks may be preyed upon by other sharks.  This species of shark breeds in the spring followed by a gestation period of around a year.  The mother then gives birth to anywhere between 4 to 17 fully grown pups.  It takes roughly five to seven years for these creatures to reach sexual maturity.


References: "Florida Museum of Natural History Ichthyology Department: Lemon Shark." Florida Museum of Natural History. Web. 24 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/LemonShark/LemonShark.html>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 442-443. Print.
            

Jan 20, 2011

Loggerhead Turtle

Loggerhead turtles are just as massive as they are magnificent.  Adults can grow as large as 8 feet and 450 Ibs.  Sea turtles are identified by their shell patterns which are formed by three sets of plates: 1) central plates- the plates that run down the center of the shell,  2) costal plates- these plates run parallel to the central plates on their side,  3)  bordering plates- small plates on the shell's edge, and finally, the front center bordering plate is known as the nuchal.  Loggerhead turtles have five costal plates, two of which touch the nuchal.  Atlantic ridley turtles have the same shell pattern but can be distinguished by their smaller bodies and olive-green to gray shells.  Loggerheads, on the other hand, have thick heads and reddish brown shells.

The scientific name for the loggerhead turtle is Caretta caretta and it belongs to the phylum Chordata and class Reptilia.  Reptiles are a diverse class containing turtles, alligators, crocodilles, lizards, and snakes.  All reptiles breath air, lay eggs, have scales, and are ectotherms.  The order Testudines, or turtles, is characterized by a hard shell that surrounds the body of the organism.  The shell is composed of two parts: one, the carapace, or the top shell and two, the plastron, or the bottom shell.  The two are joined together by another piece of the shell called the bridge.

The loggerhead turtle is a circumglobal organism found in temperate, subtropical, and tropical waters.  In the Atlantic, loggerheads have been seen has far north as Canada and as far south as Argentina.  The largest Atlantic population of loggerhead turtles are found in Florida.  These creatures more specifically inhabit offshore reefs, bays, inshore lagoons, and estuaries.  The loggerhead turtle is omnivorous mainly feeding on sponges, small crustaceans, molluscs, various fish, jellyfish, seagrass, and seaweeds.

The life cycle and history of these turtles are fascinating.  Loggerhead turtles can live upwards of 50 plus years.  Additionally, these creatures don't reach sexual maturity until they are 20 to 35 years old.  Mating itself occurs at sea but like all sea turtles, loggerheads lay their eggs on land.  In the spring and summer, female loggerhead turtles arrive during the night on mainly Florida beaches to lay their eggs.  They dig holes with their fins, deposit the eggs, bury them, and return to the ocean.  Females lay between 100-120 eggs and may repeat this process two to four times a season.  Eggs require around two months to hatch.

Loggerheads can often be found under reef ledges napping
Since the 1970's, loggerhead turtles have been considered by both the Florida Fish and Wildlife Conservation Commission (FFWCC) and the U.S. Fish and Wildlife Service as threatened.  Due to a recovery plan put in place by these organizations, loggerhead turtles have increased in recent years.  The main cause for the turtles decline and placement on the threatened species list is due to costal development, pollution, and by-catch in fishing trawlers.  Since loggerhead turtles have such as slow life cycle, these organisms need to be constantly monitored to make sure the population is healthy.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. Print.; "Carett Carett." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 21 Jan. 2011. <http://www.sms.si.edu/IRLSpec/Carett_carett.htm>.


Jan 19, 2011

Goliath Grouper

The goliath grouper is by far the largest reef fish.  An adult goliath grouper can reach over 8 feet and weigh over 800 pounds.  These groupers are yellowish brown to olive green in color with small dark spots over their bodies and fins.  Younger goliath groupers have slight pale vertical bars along their bodies which disappear with adulthood.  If you look closely in the top video you can see the pale bars towards this youngster's tail.

The goliath grouper, or Epinephelus itajara, is a boney fish that belongs to the family Serranidae, or sea basses.  All sea basses have large mouths, lips and a jutting lower jaw.  Additionally, sea basses have a divided dorsal fin; the front half consists of spiny projections and the back half is soft and flexible.  This fish can be further classified into the genus Epinephelus, or groupers.  Groupers are the best known members of sea basses and are defined by their stocky body shape and large mouths.  They are usually solitary fish that lurk amongst reefs and wrecks. Most groupers are also protogynous hermaphrodites; they change sex from female to male as they mature.

The goliath grouper can be found along Florida's east coast, the Gulf of Mexico, throughout the Caribbean, and down to Brazil.  These groupers are found on offshore reefs and wrecks from 15 to 130 feet.  Juveniles are usually found in inshore areas, especially mangroves and brackish estuaries.  Goliath groupers feed on crustaceans such as the caribbean spiny lobster, many different reef fish, and even young sea turtles.  Most of the time these fish are large enough that they shallow their food whole.  Younger Goliath Groupers may be preyed upon by sharks, barracudas, moray eels, as well as other groupers.  The massive adults, however, have no predators.

As mentioned earlier, most groupers are protogynous hermaphrodites, meaning they change sex from female to male as they mature through their life cycle.  Goliath groupers follow this life cycle and spawn during the summer months of July, August, and September.  They form massive mating groups on certain reefs and wrecks.  In the 1980's, only ten or so Goliath Groupers would be at these spawning sites due to intense overfishing.  In 1990 capture of these creatures was banned and today 40 or 50 individuals can now be found each year at their mating grounds.

References: Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. Print.; "Florida Museum of Natural History Ichthyology Department: Goliath Grouper." Florida Museum of Natural History. Web. 20 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/GoliathGrouper/GoliathGrouper.html>.

Jan 17, 2011

Green Moray

The green moray, or Gymnothorax funebris,  is one of the largest and most common moray eels.  It is solid green to brown in color with no markings on the body.  The morays, or Muraenidae family, have no pectoral or ventral fins.  Additionally, like all true eels (Anguilliforms), their dorsal and anal fins are fused together to form a single continuous fin that starts behind the head and ends midway down the belly.  All morays have a clear protective mucus that covers their scaleless bodies.  Adult green morays average between three to five feet, but they can grow as large as eight feet in length.

A Green Moray underneath a reef ledge
A common misconception is that eels are not fish.  They are bony fish, belonging to the class Ostiecthyes.  Another misconception is that green morays are dangerous.  Although they may bite if molested, green morays are not aggressive.  Often divers or snorkelers think that they are threatening due to the fact that they constantly open and close their mouths.  In reality, these eels, like the great barracuda, behave this way in order to move water through their gills for respiration.

The green moray can be found throughout the eastern seaboard of the United States, the Caribbean, and South America.  These eels are bottom-dwellers that inhabit rocky shorelines, reefs, and mangroves.  The green moray is a nocturnal species, but can often be found sticking its head out of various holes during the day.  At night, the green moray emerges from hiding and hunts for fish, crustaceans, and cephalopods using its keen sense of smell.  When it comes to these eel's life cycle, there is little known about green moray spawning.  The interesting aspect about their reproduction is that they produce larvae known as leptocephali.  These transparent, ribbion-like larvae surprisingly begin life with pectoral fins but then loose them as they develop.

References: "Florida Museum of Natural History Ichthyology Department: Green Moray." Florida Museum of Natural History. Web. 17 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/GreenMoray/GreenMoray.html>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 422, 425. Print.

    



Jan 16, 2011

Gray Angelfish

An adult Gray Angelfish
The gray angelfish is characterized by a gray body, a splash of yellow on the pectoral fin, and a square cut tail.  The picture to the left is an adult and the picture in the lower right hand corner is of a gray angelfish in between the juvenile and adult life stages.  This intermediate phase is evident by three vertical, white body bars, one on the head, body, and tail.  Gray angelfish juveniles are spectacular and are black with three vertical, yellow bars along the body, one on the tail, forehead, and a ring around their lips.  Adult gray angelfish are on average 10 to 18 inches but can reach as large as two feet.

Pomacanthus arcuatus belongs to the phylum Chordata, and class Osteicthyes, or bony fishes.  The gray angelfish is further classified into the family Pomacanrhidae, or angelfish family.  This family of reef fish are separated from others by their long dorsal and anal fins, rounded foreheads, and a spine extending from the rear check over the lower gill.  The family usually swims very gracefully and contains bright colors, hence their name "angelfishes."

The Gray Angelfish has an extremely wide distribution ranging from the north eastern United States, through the Caribbean, and down to Brazil.  These fish inhabit mainly reefs ranging in depths from 5 to 100 feet.  Reefs give Gray Angelfish protection from predators and a place to hide at night.  When it comes to feeding, Gray Angelfish are omnivores that primarily prey on sponges, but often consume algae and detritus. They sometimes play the role of a cleaner fish by removing parasites off other fishes.  Gray Angelfish, in turn, are preyed upon by large piscivores such as groupers.

An intermediate Gray Angelfish
Reproduction occurs during the months of April through September.  A male and female will pair up and cruise the reef while chasing any solitary individuals that approach.  Eventually, the mating pair will rise in the water column and being copulation.  The female releases roughly 25,000 to 75,000 eggs which are fertilized by the male and float to the open ocean.  The eggs hatch and begin their life in the planktonic stage.  Eventually, the larva will settle back onto a reef and the juvenile stage will begin.

References: "Florida Museum of Natural History Ichthyology Department: Gray Angelfish." Florida Museum of Natural History. Web. 17 Jan. 2011. <http://www.flmnh.ufl.edu/fish/gallery/Descript/GrayAngelfish/GrayAngelfish.html>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 19+. Print.
 

Yellowline Arrow Crab

 The Yellowline Arrow Crab's most defining feature are its spindly legs
The yellowline arrow crab is golden-brown in color with a triangular body and pointed snout.  Its exoskeleton is decorated with fine dark lines and the claws usually have purple tips.  The most noticeable feature of this crab is its long, spindly legs.  The body of the crab gets no larger than three inches in length.

Stenorhynchus seticornis is a crustacean and belongs to the same order as lobsters and shrimp.  The yellowline arrow crab is a true crab, or Brachyura.  True carbs have reduced abdomens and tails and a flattened carapace.  The first pair of legs have developed claws that are used in defense and to manipulate food.  The defining feature of true crabs is that they have four pairs of walking legs.  Hermit or porcelain crabs have only three pairs of walking legs.  The yellowline arrow crab more specifically belongs to the Majidae family of crabs, or spider crabs.

The yellowline arrow crab is found in the southern United States and throughout the Caribbean.  They are typically found on shallow, nearshore reefs.  This crab is mainly a nocturnal scavenger but will occasionally prey on tiny reef organisms.  Divers especially like to come across the yellowline arrow crab because they will give the diver a "high-five."  If one extends his or her palm slowly to these crabs they will extend one of their legs and touch their hand.

References: Humann, Paul, and Ned Deloach. Reef Creature Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2003. 166, 264. Print.

Jan 15, 2011

Florida Manatee

Trichechus manatus latirostris is one of the most commonly known marine mammals.  The Florida manatee is also historically important in that it was the first animal to be considered endangered.  In 1967, the Florida Fish and Wildlife Conservation Commission (FFWCC) listed the Florida manatee as endangered nearly six years before the Endangered Species Act of 1973 and listed certain areas as critical manatee habitat.  This was one of the first designations of critical habitat for any endangered species or marine mammal.

The Florida manatee became an endangered species due to both environmental and anthropogenic causes.  Habitat loss due to increasing population growth, watercraft collisions, entrapment in flood gates and canal locks, entanglement in fishing gear, and susceptibility to minute changes in climate have all contributed to the manatee's endangered status.  According to the Florida Fish and Wildlife Research Institute, today nearly 25% of manatee deaths are caused watercraft injury.  Boating education and regulation are the main areas were the Federal government and the FFWCC have focused on in order to protect the manatee.  Starting in the 1980's a federal recovery plan initiated and in 2006, the FFWCC downlisted the Florida Manatee from Endangered to Threatened.  Manatee populations have slightly increased since the start of the recovery plan but their downlist by the FFWCC was due to the fact that they changed their definition of "endangered."  Even though the Florida manatee is no longer an endangered species, laws that protect these creatures are constantly under attack from boaters and the boating industry.  Florida manatee populations have grown over the last couple of decades, but protecting these creatures is a continuous process.

The Florida manatee is rather easy to identify.  They typically are large creatures growing as large as 14 feet.  Manatees are gray in color and have massive bodies and a fusiform shape.  Some people think that the Florida manatee looks like large seal.  Other noticeable features are stiff whiskers on their faces, a round, flat tail that is used for movement and control in the water, and rounded forelimbs.

There are actually two species of manatees, the Florida manatee and the West Indian Manatee.  All manatees belong to the phylum Chordata.  Chordates are defined as having a notochord, dorsal hollow nerve chord, pharyngeal slits, and a post-anal tail.  Additionally, most chordates, except for tunicates and lancelets, are vertebrates.  Manatees more specifically fall into the class Mammalia.  Mammals all have mammary glands, hair coving their bodies, and relatively large brains.  They also are all vertebrates, give birth to live young, and breath air.  There are more than 100 different mammals that depend on the ocean directly for survival.  Marine mammals are divided into three separate orders: Carnivora (seals, sea otters, and polar bears), Cetaceans (whales, dolphins, and porpoises), and Sirenia which include dugongs and manatees.

The Florida manatee is not just constricted to Florida.  In the summer, Florida manatees can be found in Georgia and the Carolinas.  They have been found as far north as New York and Rhode Island.  In the winter months, Florida manatees retreat to their winter thermal areas in south Florida.  Florida manatees typically are inshore species found in inland, brackish rivers, lagoons, estuaries, mangroves, and even freshwater rivers.  Their diet typically consists of almost any kind of marine vegetation.  They are voracious eaters consuming 8% of their body weight and feeding 6-8 hours a day.

Florida manatees are social creatures, but not to the extent as other marine mammals such as dolphins or porposies.  Breading can occur during all times of the year, but manatees have low reproductive rates.  A female usually produces one calf every two to three years and the gestation period averages about 12 months.  The mother then raises that calf for another one to two years before the calf can survive on its own.  It takes another five years before the calf reaches sexual maturity.  This low rate of reproduction is another reason why it is so hard for manatee populations to recover.  Rebuilding Florida manatee populations depends on the survival of mature adults.

Interesting manatee facts: the Florida manatee can hold its breath for over 20 minutes.  Florida manatees can live to be more than 60 years old.  Florida manatees typically travel between 40-50 miles a day.  On average, a Florida manatee weighs about 1,000 pounds.  Manatees are closely related to elephants.

References: "Oceanography." Office of Naval Research Home Page. Web. 16 Jan. 2011. <http://www.onr.navy.mil/focus/ocean/life/mammals1.htm>.; "Manatee Facts." Save the Manatee Club. Web. 16 Jan. 2011. <http://www.savethemanatee.org/manfcts.htm>.; "Florida Manatee." Smithsonian Marine Station at Fort Pierce. Web. 16 Jan. 2011. <http://www.sms.si.edu/irlspec/trichec_manatu.htm>

  

           

Jan 13, 2011

Longsnout Seahorse

Longsnout Seahores, or Hippocampus reidi, have long, think snouts and slender bodies.  They range in color from black, to yellow, red, orange, and brown.  Longsnout Seahorses have a very long, curved tail and typically no skin appendages, however, their bony rings are visible under the skin.  They are some of the largest seahorses growing to be between two and four inches.

Longsnout seahorses are bony fishes; however, the skeleton consists of bony rings that support the organism's outer skin instead of a typical skeleton.  Longsnout seahorses are more specifically members of the Syngnathidae family, which include all pipefishes, leafy and weedy sea dragons, and seahorses.  Syngnathids are all characterized by trumpet-like snouts and small mouths.  Seahorses are separated from pipefish by their vertical orientation, head position, and elongated tail that is used for griping onto substrate.  Seahorses differ from sea dragons in that sea dragons have different means of movement and cannot use their tails as an anchor.

A Longsnout Seahorse anchored to some seagrass
These seahorses have a large range stretching from North Carolina to Florida and south through the  Caribbean to Brazil.  Longsnout seahorses inhabit inshore environments or offshore reefs and are typically found attached to mangroves, seagrasses, or gorgonians.  Longsnout seahorses feed on small shrimp, amphipods, and small crustaceans.  They are ambush predators, often waiting for prey to come to its anchored location.  When feeding, seahorses use their long snouts almost like a straw and suck the prey into their mouths where they swallow it whole.

The longsnout seahorse mates for life.  It is also unique in that males are the primary caretakers of the eggs and give birth to the offspring.  When a pair of longsnout seahorses mate, the female inserts roughly 1,000 to 1,500 eggs in a pouch on the male.  The male then fertilizes the eggs inside his pouch and about 14 days later gives birth to the young seahorses.  Even though large amounts of offspring are produced, only a few will make it to adulthood and reproduce.  Sadly, longsnout seahorse populations are in danger due to the removal of so many for aquariums, their practice in folk medicine, and simply in bycatch. Currently, the longsnout seahorse is considered by the American Fisheries Society as threatened.

References: "Florida Museum of Natural History Ichthyology Department: Longsnout Seahorse." Florida Museum of Natural History. Web. 13 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/LSSeahorse/lsseahorse.html>.; "Longsnout Seahorse, Coral Reefs, Fishes, Hippocampus Reidi." Monterey Bay Aquarium, California. Web. 13 Jan. 2011. <http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?id=780548>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 372-73. Print.

Banded Coral Shrimp

Stenopus hispidus, or the banded coral shrimp, is a fascinating creature.  They can be identified by their red and white banded body and claws, two pairs of long, white, hair-like antenna, a translucent body section, and enlarged middle legs that bare claws.  Banded coral shrimp are relatively small, growing anywhere from one and a half to two inches in length.

A Banded Coral Shrimp awaiting a dirty customer
All shrimp belong to the phylum Arthropoda. Arthropods have segmented legs and a hard exoskeleton. More specifically, shrimp are members to the class Crustacea.  Crustaceans have two pairs of antenna and their bodies are divided into three sections: head, thorax, and abdomen.  Banded coral shrimp also fall into the largest order of crustaceans called decopods.  Lobsters and crabs also belong to the order Decopoda.  The order can be defined as having five pairs of segmented legs and the head being fused to the thorax.  This is called the carapace.  Banded coral shrimp are further classified into the Natantia suborder, or true shrimp.  The distinguishing aspect of shrimp are their long hair-like antenna and well developed abdomen that they use for swimming.

Banded coral shrimp are cleaner shrimp, they remove and feed off parasites, dead tissue, or left over food particles on other marine creatures.  Cleaner shrimp are one of the best examples of symbiosis in reef ecology.  When these organisms are hungry, they perch near the openings of recesses and wait for marine creatures looking for a clean.  Once a fish or eel approaches the shrimp, it preforms a dance where it sways from side to side while whipping its antenna back and forth.  This indicates to the fish that the shrimp is willing to clean.  If the fish can, it signals it wants a clean by flashing colors.  The shrimp then gets busy cleaning the fish's face, gills, or even inside their mouth.  The fish then signals its departure by another flash of color or a certain movement and the shrimp exits the fish.

Since the Banded coral shrimp preforms such a helpful ecological role, they have little to no predators and a fairly wide distribution.  They are common to Florida and the Caribbean as well as the Indo-Pacific area.  More specifically, these cleaner shrimp inhabit reef systems and can often be found in small holes and crevices.  Banded coral shrimp are also interesting in that they mate for life.  When its time to mate, males will approach their recently molted female partner and preform their mating ritual.  Once fertilization occurs, the offspring are released into the water after about two weeks where they begin life as planktonic larva.

References: Schuller, Zachary. "Stenopus Hispidus, Banded Coral Shrimp." Octopus, Squid, Cuttlefish, and Nautilus - The Cephalopod Page. Web. 13 Jan. 2011. <http://www.thecephalopodpage.org/MarineInvertebrateZoology/Stenopushispidus.html>.; Humann, Paul, and Ned Deloach. Reef Creature: Identification : Florida, Caribbean, Bahamas. Jacksonville: New World Publ, 2002. 164+. Print.

  

Jan 11, 2011

Red Lionfish

Otherwise referred to as the zebrafish, the red lionfish can easily be identified by their red and white vertical stripes and their long separated dorsal fins and fan-like pectoral fins.  Red lionfish range in size, but typically grow to be a little over a foot in length.

Lionfish are an invasive species to Atlantic reefs
The red lionfish's scientific name is Pterois volitans, and it belongs to the family Scorpaenidae, or scorpionfishes.  The major characteristic that all scorpionfishes have in common is that they are venomous.  Scorpionfishes also all have fleshy appendages on their heads and have a stocky body shape.  Many species of scorpionfishes are camouflaged and use this tactic to capture prey.  The red lionfish, however, is in no way camouflaged and makes its highly venomous dorsal and pectoral fins known.  Instead of ambushing, the red lionfish uses its fan-like pectoral fins to corner its prey where it then makes a quick lunge and swallows it whole.

Red lionfish are an invasive species in these waters.  They are native to the Pacific ocean and are commonly found from western Australia to French Polynesia.  Since red lionfish are not endemic to Atlantic reef systems, they have no known predators.  With no population control, red lionfish have flourished in the Atlantic and can now be found throughout the Caribbean, Florida, and even as far north as Long Island.  Unfortunately, Lionfish possess incredible appetites and consume shrimp, small fish, and the young of many important commercial fish species such as snappers and groupers.

The only good Lionfish is a dead Lionfish
It is still unknown the impact red lionfish will have on both the Atlantic reef systems and the commercial fishing industry.  The good news is that red lionfish are delicious and a campaign is underway in the Caribbean to promote red lionfish as food for islanders.  In Florida, the recreational diving community has been at the forefront of Red Lionfish control through spearfishing.  Many dive shops, conservation groups, and concerned divers have put together lionfish hunting tournaments with prize money for the team who kills the most red lionfish.  These methods certainly cannot eliminate red lionfish, but they can attempt to keep them at manageable levels and slow red lionfish population growth.

Even with these initatives, controlling red lionfish populations will be a chanllenge due to its life cycle.  A single female red lionfish produces between 2,000 and 15,000 eggs each time she mates.  When spawning season arrives females externally release their eggs and males then fertilize them.

References: "Pterois Volitans." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 11 Jan. 2011. <http://www.sms.si.edu/irlspec/pterois_volitans.htm>.

Bearded Fireworm

Hermodice carunculata, otherwise known as the bearded fireworm, can be identified by short white tufts that protrude from each body segment and a branched appendage of flesh on the head called a caruncle.  The bearded fireworm's color can vary from red, green, yellow, or even brown.  Usually they grow to an average of four to six inches but can be found as large as a foot in length.

The white bristles are venomous and cause a painful burning sensation
The bearded fireworm is an annelid, or segmented worm.  Both earthworms and marine worms belong to this phylum.  The phylum Annelida is characterized by repetitive body segments which separate the organism's body. More specifically, fireworms are polychaetes (bristleworms).  Organisms in the class Polychaeta are generally marine annelids that have protrusions from each body segment, called parapodia, that bare many bristles called chaetae.

With fireworms, these bristles are the main defense mechanism for the organism.  When disturbed, bearded fireworms erect their bristles which are easily detachable and penetrable.  The bristles produce an intense burning sensation around the area of contact, hence the common name of the species.

Bearded fireworms consume small and hard corals, anemones, and small crustaceans.  Their effect on corals can be substantial.  These organisms will eat the branching ends of corals leaving only white markings as evidence.  Bearded fireworms are typically found on reefs or under rocks on sandy bottoms.  They are common to Florida and other tropical regions in the Atlantic.  Even though Bearded fireworms are bottom dwelling organisms, they reproduce on the surface.  Females begin the process by emitting a greenish phosphorescent glow.  This attracts males which give a similar flash.  The gametes are then released into the water where they combine.

References: "Bearded Fireworm, Hermodice Carunculata at MarineBio.org." MarineBio.org - Marine Biology, Ocean Life Conservation, Sea Creatures, Biodiversity, Oceans Research...Web. 11 Jan. 2011. <http://marinebio.org/species.asp?id=292>.; Humann, Paul, and Ned Deloach. Reef Creature: Identification : Florida, Caribbean, Bahamas. Jacksonville: New World Publ, 2002. 140-43. Print.

Jan 9, 2011

Sheepshead

Sheepsheads are easily identified by numerous dark vertical markings on the body.  They get their common name from their impressive sheep like teeth. Sheepsheads typically grow to about one and a half feet but can grow as large as three feet.

Sheepsheads are generally bottom feeders
The sheepshead's scientific name is Archosargus probatocephalus and they belong to the class Osteichthyes, or bony fishes.  Sheepsheads are in the family Sparidae, or porgies.  Sparids are silvery fishes with a steep sloping face and mouths well below the eyes.  Their silver bodies usually have a light coloration or varying head and body markings.  Porgies are typically solitary, bottom dwellers that snack on crustaceans throughout the day.    

Sheepsheads are omnivores that feed on plant matter, invertebrates and small vertebrates.  Some of their favorite foods are blue crabs, oysters, clams, crustaceans, and small fish, such as young Atlantic croakers. Sheepsheads use their hard teeth to break shells and other exoskeletons.  Their teeth are strong enough to break barnacles off rocks.  These fish are in turn food for many different piscivorous fishes and sharks.

Sheepsheads can be found along the entire Atlantic seaboard and are common to Florida.  They are not found in the Bahamas or the Caribbean.  Sheepsheads occupy a wide variety of habitats ranging from inshore lagoons and brackish bays to offshore rock pilings, wrecks, and reefs.  Generally sheepsheads are found offshore during the spawning months where they congregate to mate.  After mating has occurred, they typically move back to inshore environments.

References: "Florida Museum of Natural History Ichthyology Department: Sheepshead." Florida Museum of Natural History. Web. 09 Jan. 2011. <http://www.flmnh.ufl.edu/fish/Gallery/Descript/Sheepshead/Sheepshead.html>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 40, 72-73. Print.

Jan 8, 2011

Great Barracuda

A Great Barracuda calmly watching potential prey
With its large, silvery body, razor sharp teeth, and crazed stare, the great barracuda is an intimidating sight.  Their defining feature is a large underslung jaw containing numerous pointed teeth. Additionally, great barracudas usually have dark blotches and side bands along their slender, conical bodies.  They are typically between one and three feet but can grow as large as six feet.

The scientific name for the great barracuda is Sphyraena barracuda.  They belong to the class Ostiechythes, or bony fishes, and the family Sphyraenidae, or barracudas.  The barracuda family is defined by an elongated body figure, long jaws, a large forked tail, and two, low, widely separated dorsal fins.  

The great barracuda is found in tropical waters throughout the world.  Adults are usually more solitary than juveniles and can be found on offshore reefs, sand flats, and along mangrove forests.  The great barracuda's diet is fairly simple; they are piscivores.  Some of their favorite fish are ballyhoo, triggerfishes, and mullet.  When capturing prey, barracudas use their lighting speed to hunt down their food and numerous teeth to shear it into more manageable pieces.  The great barracuda's teeth are so sharp that it can cut a fish in half with a single bite.

Little is known about the reproduction of great barracudas.  Scientists know that they reproduce sexually through external fertilization.  In south Florida, adult barracudas spawn from early spring to fall by releasing their eggs or sperm into the water column.  The fertilized eggs then hatch in open water where they begin their first stages of life.

References: "Sphyrae Barracuda." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 08 Jan. 2011. <http://www.sms.si.edu/irlspec/Sphyrae_barrac.htm>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 40, 63-64. Print.

Jan 7, 2011

Caribbean Spiny Lobster

Panulirus argus goes by many different names: spiny lobster, Florida lobster, Caribbean spiny lobster, rock lobster, or simply bug.  Caribbean spiny lobsters are easily identified by their tan and brown color, light spots on their abdomen, sharp horns above their eyes, and two long conical antennae. Caribbean spiny lobsters typically grow to an average size between six and ten inches but can grow as large as two feet.

Caribbean spiny lobsters belong to the phylum Arthropoda, the largest phylum in the animal kingdom.  Arthropods have segmented legs and a hard exoskeleton.  More specifically, Caribbean spiny lobsters belong to the subphylum Crustacea.  Crustaceans are distinguished by two pairs of antenna and three distinct body parts: head, thorax, and abdomen.  Caribbean spiny lobsters also fall into the largest order of crustaceans called Decapoda.  Decapods have five pairs of legs, and the head if fused to the thorax.  This is called the carapace.  Decapods include shrimp, carbs, and of course lobsters.  All lobsters live on the sea floor and mainly move by walking, but they also have the ability to quickly swim backward if frightened.

A Caribbean Spiny Lobster in his protective hole
Caribbean spiny lobsters feed on a wide variety of organisms including gastropods, bivalves, other crustaceans, annelids, and echinoderms.  They are in turn food for the goliath grouper, many different sharks, loggerhead turtles, octopods, and humans.  The Caribbean spiny lobster is common in tropical and subtropical waters extending from the carolinas to Brazil.  The life cycle of these organisms begins in the open ocean as larva.  As they enter the swimming and juvenile stages, the lobsters migrate to inshore waters where they stay until adulthood.  Adults are usually found offshore in the crevices of reefs or underwater structures.  Caribbean spiny lobsters spawn between the months of March and June, and reproduction occurs outside of the body.  Male lobsters give the female a spermatophore which is then inserted inside the female.  Once the female is ready to lay her eggs, she finds a protected place and deposits the eggs.  Sometime later the eggs hatch, and the larva are swept away to the open ocean where the first life stage begins.

References: "Indian River Lagoon Species Inventory Homepage." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 07 Jan. 2011. <http://www.sms.si.edu/IRLSpec/index.htm>.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 164-65, 188-89. Print.

Nurse Shark

Nurse sharks can be identified by the two barbs on the upper lip
The nurse shark can be identified by two barbs protruding from the upper lip, two dorsal fins of nearly equal size positioned far back on the organism, and a small mouth.  Nurse sharks can range in color from gray to yellow brown and are typically between five and nine feet.  They can reach as large as 14 feet.

The nurse shark, or Ginglymostoma cirratum, belongs to the class Chondrichthyes, or cartilaginous fishes.  This class contains all sharks and rays.  The nurse shark belongs to the Ginglymostomatidae family, or carpet sharks.  Carpet sharks are closely related to the whale shark family Rhincodontidae, the largest fishes in the world.  The name, nurse shark, is thought to derive from "nusse," the common name applied to cat-sharks, in which nurse sharks were thought to belong.  In many parts of the caribbean the nurse shark is still called "tiburon gato," or cat-shark.

Nurse sharks are nocturnal and often can be seen sitting on the sea floor during the day, hence their family "carpet" sharks.  They are common to shallow water reefs up to 100 feet.  The nurse shark's main diet consists of fish, sting rays, molluscs, and crustaceans.  To capture their prey, nurse sharks use a high speed sucking force.  This method is thought to allow the nurse shark to feed on small fish that are hiding at night and remove molluscs and crustaceans from their shells.

A nurse shark resting in the sand
When it comes to reproduction, marine biologists have a fairly good understanding of these sharks.  nurse sharks reproduce for five weeks during the summer by gathering in their regional shallow water breeding grounds.  Females are quite stubborn and fight off males as they attempt to mate.  Eventually, males will bite and wrestle female nurse sharks until they concede to mate.  Once the the female has agreed to mate, the male must cling to the female's fin with his mouth, roll her over, and then begin copulation.  The eggs hatch inside the mother and gives birth to roughly 20 to 30 pups.

References: DeLoach, Ned, and Paul Humann. Reef Fish Behavior: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2007. 306-08. Print.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 440-43. Print.

Jan 5, 2011

Stoplight Parrotfish

The stoplight parrotfish, or Sparisoma viride, can be rather hard to identify due to the dramatic phenotypic changes that can occur as the organism matures.  One of the defining features of the Scaridae family, or parrotfishes, is the division of maturity into three phases: a juvenile phase (JP), initial phase (IP), and terminal phase (TP).  In the IP, spotlight parrotfish can be identified by a reddish/brown head and body, a red belly, mixed white scales, and a tan and red crescent shaped tail.  The stoplight parrotfish is usually 5-10 inches in the IP.  When spotlight parrotfish mature to the TP they can be identified by their emerald green color, salmon to yellow markings on the fins, and a small bright yellow spot above the gill.  Stoplight parrotfish in the TP can reach up to 24 inches.
A spotlight parrotfish in the initial phase

Stoplight parrotfish belong to the class Osteichthyes, or bony fishes, and the family Scaridae.  All scarids have powerful jaws, fused teeth that resemble a beak, and bright colors.  Their beaks are used to scrape filamentous algae from coral or even bite into coral itself.  Parrotfish are closely related to the labridae family, or wrasses.  Both parrotfish and wrasses swim predominately with their pectoral fins, are generally dichromatic, and have very complex social mating hierarchies.  Scarids, along with wrasses, are protogynous hermaphrodites.  In other words, all female parrotfish that live long enough change sex.  Fish in the IP are therefore mostly female while fish in the TP are exclusively males.  A typical population of parrotfish contains a few dominant TP males, mostly IP females, and some sexually immature JP fish.

As for stoplight parrotfish, they seem to have a very flexible social structure compared to that of other parrotfish species.  With abundant food sources, the spotlight parrotfish live in non-territorial groups; however, under low resources dominant males become very territorial and reside in a particular part of the reef with several IP females.  These territories are called harems.  When it comes to reproduction, stoplight parrotfish spawn during 90 minute periods throughout the year.    

Stoplight parrotfish also have similar diets to other parrotfish species; they eat mainly filamentous algae, algal bushes, sea grass blades, an occasional crustacean, and sometimes sponge.  Stoplight parrotfish have a tendency to consume more hard coral than other parrotfish species.  Most parrotfish ingest the coral skeleton as a byproduct of consuming filamentous algae; however, stoplight parrotfish frequently take whole bites out of coral.  In fact, they have a five times greater consumption of coral than most parrotfish.  Since calcium carbonate cannot be digested, parrotfish play an major role in creating sand in tropical regions.

References: DeLoach, Ned, and Paul Humann. Reef Fish Behavior: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2007. 280-96. Print.; Humann, Paul, and Ned DeLoach. Reef Fish Identification: Florida, Caribbean, Bahamas. Jacksonville, FL: New World Publications, 2002. 192-99. Print.



Jan 4, 2011

Cushion Sea Star

A cushion sea star on a sandy inshore flat 
Oreaster reticulatus, or the cushion sea star, can be identified by its orangish brown to tan color, large body, raised spines that form geometric designs of contrasting color, and thick, short arms.  It is a large sea star growing up to be 8-14 inches.

The cushion sea star belongs to the phylum Echinodermata.  All echinoderms are marine organisms that have have five body segments of roughly equal length that radiate from a central axis, and a hard, internal skeleton. Echinoderms also have hundreds of small feet, called podia, that used for movement or capturing prey.   Echinoderms are the most closely related animals to chordates.  More specifically, the cushion sea star belongs to the family Asteroidea, or starfish.  Asteroids can be defined as having five arms of equal length which merge in the center.

Cushion sea stars tend to inhabit inshore sea grass beds or sandy flats.  These organisms are omnivores and feed on sponges, microorganisms, copepods, ostracods, carb larvae, echinoids, and many invertebrates.  When feeding, cushion sea stars, along with all starfish, protrude their stomach over their prey and digest it outside of the body.  The food is then absorbed through the mouth on the underside of the starfish.  In the picture above, this particular cushion sea star is heading towards its next meal: a sea urchin in the upper right hand corner.

These organisms reproduce sexually once a year in the summer.  In more tropical regions, cushion stars reproduce year round.  Starfish also have interesting regeneration abilities.  A single removed segment can generate another entire sea star.

References: Humann, Paul, and Ned Deloach. Reef Creature: Identification : Florida, Caribbean, Bahamas. Jacksonville: New World Publ, 1996. 350-51 & 366-67. Print;
"Oreaster Reticulatus." Smithsonian Marine Station (SMS) at Fort Pierce. Web. 04 Jan. 2011. <http://www.sms.si.edu/irlspec/Oreaster_reticulatus.htm>.