Unique, beguiling seahorse faces dwindling numbers
Beautiful creature mates exclusively with same partner for entire life span

By BOBBIE CLINE,
SPECIAL TO THE NEWS-PRESS
Published by news-press.com on June 25, 2005

It may have the head of a horse, a tail like a monkey and a pouch like a kangaroo, but the seahorse (hippocampus) is actually a fish - a fascinating fish.

This genus of fish is found in temperate and tropical coastal waters worldwide. They inhabit warm, shallow areas among seagrass beds, mangroves, corals and estuaries in and around Lovers Key State Park.

There are 35 known species of seahorses, which range in length from less than an inch to 5 inches. One of the most unusual in appearance of all fishes, the seahorse is a beautiful creature with some remarkable adaptations.

The seahorse's body is protected by strong external plates arranged in a series of rings. Although these rings, like jointed armor, protect the fish by making it unpalatable to other animals, they also cause a limited flexibility of the body.

Its prehensile tail, which coils forward, is used to wrap itself around stems of vegetation as an anchor in the current.

Lacking a tail fin, which provides most fish with swimming power, seahorses cannot swim fast. They can swim forward and backward by undulation of their dorsal and pectoral fins and can hover precisely, with the dorsal fin beating 35 times a second.

Seahorses have heads that look like horse heads with a coronet, or little crown, on top. The eyes can swivel independently and, because of their placement, it is believed the seahorse has binocular vision.

Its snout is like a straw and is used to suck up bottom-swarming organisms such as plankton and brine shrimp. Lacking teeth and a stomach, it swallows its food whole with a rapid snap of the head.

A seahorse can consume up to 3,000 brine shrimp a day.

Seahorses are known for their ability to change color depending on their habitat, what they have eaten and as part of a courtship ritual. This ability for camouflage provides an important survival mechanism against such predators as crabs, skates and sea turtles.

Unique to this species is the fact that the male seahorse has a pouch on its stomach to carry babies — as many as 2,000 at a time.

The reproductive process begins when the male and female perform a beautiful dance, intertwining their tails and swimming together.

This courtship dance can last as long as eight hours, ending when the female sprays her eggs into the male's pouch. The eggs are then fertilized, and the male cares for them approximately 2 to 6 weeks.

He aerates the pouch and nourishes the eggs with his own placental fluids.

At the end of the pregnancy, he flexes his body back and forth, the pouch opening widens and babies begin to emerge.

Approximately 100 to 250 (not all eggs survive) fully developed young seahorses, about 1 centimeter in length, emerge in small batches, then swim to the surface to gulp water before swimming away to fend for themselves.

Within 8 to 10 months, they will reach their maximum size of 5 inches in length. Few reach maturity because of natural predators and storms that can tear them from the vegetation on which they cling, causing them to die of exhaustion.

The male soon becomes pregnant again and the process repeats itself. The seahorse is unusual in that it is monogamous, meaning it will mate exclusively with the same partner during its lifetime.

Seahorse habitats are among the most threatened in the world because of pollution, destructive fishing methods and shoreline alterations.

They are exploited for traditional Chinese medicines, home aquariums and tourist mementoes.

More than 20 million are collected each year, and recovery is made difficult because of seahorse monogamy and a life span of only 1 to 5 years.

If one member of a pair is destroyed, its partner will stop reproducing.

Project Seahorse, of McGill University in Montreal, which is an international organization committed to conservation of the world's coastal marine ecosystems, has assessed global seahorse populations and discovered a decline of 50 percent in the last five years.

These fascinating creatures can be prevented from disappearing through education, conservation and environmental protection.

For more information, visit Lovers Key State Park and join a guided beach walk free with park admission.

Lovers Key State Park is open 365 days a year from 8 a.m. until sundown.

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