Barracudas Swordfish ,Sailfish, Blowfish and Midshipmen

Barracudas

Scientific classification

Kingdom: Animalia

Phylum: Chordata

Class: Actinopterygii

Order: Perciformes

Family: Sphyraenidae

Genus: Sphyraenus



Species (25 species)



The barracuda (Sphyraenus, family Sphyraenidae) is a ray-finned fish notable for its large size (up to 1.8 m or 5 ft) and fearsome appearance. Although attacks on humans are known, barracudas are primarily voracious predators on other fish. The one genus of the family includes about 25 known species.

The barracuda body is elongated, with the lower jaw of the large mouth jutting out, and displaying prominent fang-shaped teeth. The two dorsal fins are widely separated, with the first having five spines and the second one spine and nine soft rays. The lateral line is prominent.

A school of barracuda.Their body plan is a classic example of a lie-in-wait or ambush predator: barracudas rely on surprise and short bursts of speed to overrun their prey, sacrificing manoeuvrability.

Barracudas occur in subtropical and tropical oceans worldwide, and may be seen in schools, particularly during spawning. They are caught as food and game fish (however, barracuda flesh can occasionally contain ciguatera toxin), and scuba divers often see them cruising above coral reefs.



Swordfish









: Quick Facts about: Animal A living organism characterized by voluntary movementAnimalia

: Quick Facts about: Chordata Comprises true vertebrates and animals having a notochordChordata

: Quick Facts about: Actinopterygii Quick Summary not found for this subjectActinopterygii

: Perciformes

: Xiphiidae

: Xiphias

: gladius



Binomial name



Xiphias gladius

Swordfish (Xiphias gladius) are large, highly migratory Quick Facts about: predator Any animal that lives by preying on other animalspredators characterized by a long, flat bill in contrast to the smooth, round bill of the Quick Facts about: marlin Large long-jawed oceanic sport fishes; related to sailfishes and spearfishes; not completely cold-blooded i.e. able to warm their brains and eyesmarlins. Swordfish are elongate, round-bodied, and lack teeth and scales as adults. They reach a maximum size of 14 ft (4.3 m) and 1,190 lb (540 kg). The International Game Fish Association's all-tackle angling record is a 1,182 lb (536 kg) fish taken off Quick Facts about: Chile A republic in southern South America on the western slopes of the Andes on the south Pacific coastChile in 1953.

Swordfish are distributed throughout the world's marine ecosystem, in tropical, subtropical and temperate waters and tend to concentrate where major Quick Facts about: ocean current The steady flow of surface ocean water in a prevailing directionocean currents meet, and along temperature fronts. They inhabit the mixed surface waters where temperatures are greater than 15 °C but also can move into water as cool as 5 °C for short periods aided by specially adapted brain and eye heat exchange organs.

Areas of greater apparent abundance occur north of Quick Facts about: Hawaii A state in the United States in the central Pacific on the Hawaiian IslandsHawaii along the North Pacific transition zone, along the west coasts of the U.S. and Quick Facts about: Mexico A Republic in southern North America; became independent from Spain in 1810Mexico and in the western Pacific, east of Quick Facts about: Japan A constitutional monarchy occupying the Japanese Archipelago; a world leader in electronics and automobile manufacture and ship buildingJapan. Migration patterns have not been described although tag release and recapture data indicate an eastward movement from the central Pacific, north of Hawaii, toward the U.S. West Coast. Acoustic tracking indicates some Quick Facts about: diel Quick Summary not found for this subjectdiel movement from deeper depths during the daytime and moving into the mixed surface water at night. At times they appear to follow the deep scattering layer, and small prey, as they undertake these vertical movements.

Females grow larger than males, as males over 300 lb (135 kg) are rare. Females mature at 4-5 years of age in northwest Pacific while males mature first at about 3 to 4 years. In the North Pacific, batch spawning occurs in water warmer than 24 °C from March to July and year round in the equatorial Pacific. Adult swordfish forage includes pelagic fish



SAILFISH

Sailfish (Istiophorus platypterus) are four to five foot long fish living in the Atlantic Ocean. They are blue in color and have a characteristic sail on top of them, stretching the entire length of their back. They frequently can attain speeds of 50 knots. Description: color dark blue on top, brown-blue laterally, silvery white underbelly; upper jaw elongated in form of spear; first dorsal greatly enlarged in the form of a sail, with many black spots, its front squared off, highest at its midpoint; pelvic fins very narrow, reaching almost to the anus; body covered with embedded scales, blunt at end; lateral line curved above pectoral, then straight to base of tail.

Similar Fish: white marlin, Tetrapterus albidus; young blue marlin, Makaira nigricans (spectacular sail-like dorsal of sailfish is most notable difference).

Where found: OFFSHORE species, in south Florida associated with waters near the Gulf Stream; off the Panhandle near the 100 foot fathom line.

Size: common to 7 feet.

Florida Record: 116 lbs. Remarks: rapid growing species, reaching 4 to 5 feet in a single year; swims at speeds up to 50 knots; feeds on the surface or at mid-depths on smaller pelagic fishes and squid.



BLOWFISH AKA PUFFERFISH

Puffer, Arothron hispidus Scientific classification

Kingdom: Animalia

Phylum: Chordata Subphylum: Vertebrata

Class: Actinopterygii Order: Tetraodontiformes Family: Tetraodontidae

Genera

Amblyrhynchotes

Arothron

Auriglobus

Canthigaster

Carinotetraodon

Chelonodon

Colomesus

Contusus

Ephippion

Feroxodon

Fugu

Gastrophysus

Javichthys

Lagocephalus

Liosaccus

Marilyna

Monotretus

Omegaphora

Pelagocephalus

Polyspina

Reicheltia

Sphoeroides

Takifugu

Tetractenos

Tetraodon

Torquigener

Tylerius

Xenopterus

The pufferfish, also called blowfish, swellfish, globefish, balloonfish are fish making up the family Tetraodontidae, within the order Tetraodontiformes. They are named for their ability to inflate themselves to several times their normal size by swallowing water or air when threatened; the same adaptation is found in the closely related porcupinefish, which also have spines (unlike pufferfish).

The eyes and internal organs of most pufferfish are highly toxic, but nevertheless its meat is considered a delicacy in Japan. The name fugu is used both for the fish that are eaten and for their meat. (For more details see Fugu)

There are 185 known species of the family Tetraodontidae, of which 38 can be found in Japan. They can be found worldwide from about 45° latitude north to 45° latitude south, mostly in salt water near coral reefs or the shore, but some species also live in fresh water or brackish water.

The pear-shaped pufferfish is a slow swimmer, and mainly uses its small pectoral fins for propulsion, which does not allow it to escape predators very well. In case of danger, they inflate themselves by filling their extremely elastic stomach with water (or air when outside the water) until they are almost spherical. In case this defense fails, pufferfish also contain a powerful neurotoxin in their internal organs, making them a lethal meal for most predators. It is found mainly in the ovaries and liver, to a lesser extent in the intestines and skin, and only in small amounts in the muscles and blood.

The toxin is called tetrodotoxin, or more precisely anhydrotetrodotoxin 4-epitetrodotoxin and is about 1200 times deadlier than cyanide. This poison can also be found in other animals such as the Blue-Ringed Octopus, Cone Snails, or even some newts. The pufferfish does not create the poison itself; rather it is generated by various genera of bacteria within the fish. The fish obtains the bacteria by eating food containing these bacteria. Pufferfish that are born and grown in captivity do not produce tetrodotoxin until they receive some of the poison-producing bacteria, often by eating tissues from a toxin-producing fish. Also, some fish are more poisonous than others. A poisonous fish has enough poison to kill 30 adults.

Tetrodotoxin is a very potent neurotoxin and shuts down electrical signaling in nerves by binding to the pores of sodium channel proteins in nerve cell membranes. It does not cross the blood-brain barrier, leaving the victim fully conscious while paralyzing the remainder of the body. In animal studies with mice, 8μg tetrodotoxin per kg body weight killed 50% of the mice. The pufferfish itself has immunity to the poison due to a mutation in the protein sequence of the sodium channel pump on the cell membranes.

Apparently due to some unknown selection pressure, intronic and extragenic sequences have been drastically reduced within this family. As a result, they have the smallest-known genomes yet found amongst the vertebrate animals, while containing a genetic repertoire very similar to other fishes and thus comparable to vertebrates generally. Since these genomes are relatively compact it is relatively fast and inexpensive to compile their complete sequences, as has been done for two species (Takifugu rubripes and Tetraodon nigroviridis).

Pufferfish are also one of few kinds of fish that can blink or close their eyes. (Some claim they are the only fish that can close its eyes, but certain attacking sharks close their eyes to protect themselves from struggling prey).



Trivia Puffy the pufferfish has been chosen as the mascot of the OpenBSD project.





Humming Fish Facts aka MIDSHIPMEN

NOT THE UNIFORM. Called midshipman fish because some varieties of Porichthys notatus have bioluminescent spots that resemble rows of uniform buttons, they are also known as California singing fish and canary bird fish. Females probably aren't attracted to the uniform but rather to the male's song.

PICENE BOOMBOXES. When the midshipman migrate from the deep Pacific waters to the west coast of North America to mate each summer, the intertidal zone becomes a noisy place. Courting males hum to attract egg-laying females. The love song, described as a motorboat-like drone, comes from rapidly contracting muscles on the male's swim bladder and proves irresistible to female midshipman. Each female deposits all her eggs for that season in one nest and swims away. Hoping to lure more females to the nest, the male resumes singing, all the while remaining on guard until the offspring hatch and mature.

SNEAKER MALES. Not guys in Air Jordans but morphs with an attitude, the so-called Type II or sneaker males are smaller and less vocally talented than Type I males. Unable to attract females because they can't sing, sneaker males hang around nests where Type I males are humming and quickly dart in to fertilize some eggs. They frequently get away with this behavior, probably because they closely resemble the smaller females.

THAT TAKES TESTES. What sneaker males lack in vocal repertoire and size, they more than make up in reproductive capacity. Studies at Cornell have shown that the gonads of Type II sneaker males comprise up to 15 percent of their body weight, compared with only 1 percent in Type I males. The equivalent in a 150-pound human male would be 22.5-pound testes.

BIG VOCABULARY. Don't think humming fish hum because they don't know the words. They produce two others kinds of vocalizations that, if not especially eloquent, do get the message across: A series of grunts that bioacoustic scientists call a "grunt train" and a low growl both come from Type I males guarding their nests. Type II males have been heard making an occasional grunting sound but always in non-spawning situations.

ALL EARS. Only certain fish species are capable of vocalizing, but virtually all fish have ears to keep them in tune with their sound-filled environment. Cornell biologists who conduct acoustic playback experiments with midshipman fish in outdoor aquariums report that female midshipmen are easily attracted to their computer-synthesized hums. But simulated grunts, they say, "seem to do nothing for the females."







Sources Cornell University , Wonders Under The Sea, The Glorious Ocean

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