Tuesday, October 16, 2007

seahorse

There are 37 known species of seahorses. They are in the Family of Syngnathidae and Genus of Hippocampus.

General Description:
The have a horse-like head, monkey-like tail, and kangaroo-like pouch. In fact, even their eyes can be likened to those of a chameleon in that they move independently of each other and in all directions. Instead of scales, seahorses have thin skin stretched over a series of bony plates that are visible as rings around the trunk. Some species also have spines, bony bumps, or skin filaments protruding from these bony rings. A group of spines on the top of the head is referred to as the coronet, and looks like a crown. Seahorses are masters of camouflage, changing colour and growing skin filaments to blend in with their surroundings. Short-term colour changes may also occur during courtship displays and daily greetings. Male and female seahorses can be told apart by the presence of a brood pouch on the male.

Functions of Body Parts:
-1 Dorsal fins: moves fish forward, using the propulsive force of the quickly oscillating dorsal fins
-1 tiny anal fin: balance
-2 tiny pectoral fins on either side of the bod: control turning, steering, and stability
-coronet: is nearly as distinctive as a human thumbprint, shape are useful in separating species.
-1 tail: hold on to objects such as seagrass
-2 eyes: binocular vision, eyes of seahorses can move independently
-strong external plates: hard bony armour, which are arranged into a series of 'rings'. These rings help to protect the body of the fish, but result in the fish having only limited flexibility of the body. the number of trunk and tail rings doesn't vary much among individuals of a species, but does differ between species, so it is a handy character for telling species apart.
-ability to change color:
change color and grow skin filaments to blend in with their surroundings for protection



Living Habits
eating: Three movements:
1.a rapid upward movement of the head,
2. a lowering of the floor of the mouth to make it bigger,
3. opening of the mouth.
All three occur almost simultaneously, resulting in prey being sucked in through the mouth and up the long tube-like snout. Often an animal too large for the seahorse's mouth, such as a small fish, may be ripped apart by the strong suction. Soft pieces are ingested, as the more solid parts are discarded.

diet: shrimps, crabs, and crayfish, fish fry, and other small invertebrates. Each day a seahorse can consume up to 3,000 brine shrimp.

Habitats: Seahorses are usually found in water less than 65 feet deep, but have been trawled from depths approaching 500 feet. Some may be found among seagrasses or eelgrasses, or among mangrove forests, corals, or on sea fan gorgonians.

They are more adapted to maneuverability than speed, cannot swim fast due to lack of tail fin.

low adult mobility and small home ranges

Most species of seahorse studied in the wild do appear to be monogamous, remaining faithful to one partner for the duration of the breeding season and perhaps even over several seasons.

Lifespan: from about one year in the smallest species to an average of three to five years for the larger species.

Male carries the baby. A brood may number from an average of about 300 to as many as 700 offspring. Gestation varies with temperature, but averages around 28 days.

More active during daytime


http://www.divegallery.com/seahorse_page1.htm
jeff’s nudibranch Site and coral reef gallery

http://www.seahorse.org/

http://seahorse.fisheries.ubc.ca/
project seahorse

http://www.pbs.org/wgbh/nova/seahorse/basics.html
nova online


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