Tampa Bay is home to scores of marine life, but few are as enchanting or marvelous to behold as the seahorse.

These whimsical creatures with equine heads often hide camouflaged among seagrass meadows, swaying in the current, holding on by curling their sinuous monkey-like tails tightly around the grass blades. They feed by slurping up tiny zooplankton with their tubular trumpet-like snouts. Their eyes move independently of each other like a lizard's, and when they swim, their tiny fan-shaped pectoral fins flutter almost as madly as a hummingbird's wings. They have bony plates of armor covering their bodies like a sturgeon's, and they can radically change color like a chameleon.

So why don't we hear, see or know more of these fascinating fishes that have seemingly jumped off the pages of a fantasy novel and plunged into our estuary? Because the truth is, no one has taken the time to study them in detail in Tampa Bay... until now.

University of Tampa Assistant Professor Heather Masonjones is mapping seahorse populations in Tampa Bay, along with their stretched-out relatives, the pipefish. The research is sponsored by the Tampa Bay Estuary Program, which is interested in the status of seahorses as a barometer of the overall health of the bay.

Scientists have identified 33 different seahorse species around the world, but it is the diminutive dwarf seahorse, Hippocampus zosterae, that has captured Masonjones's attention. The dwarf seahorse inhabits coastal ecosystems such as the shallow grass beds, salt marshes and mangroves of Tampa Bay and the Florida Keys. Measuring only one to two inches from the top of their heads to the tips of their tails, these animals are more like the "ponies" of the seahorse family compared to their giant 12-inch-long relatives found in the Pacific.

Although the dwarf seahorse is small in stature, Masonjones has a hunch that these tiny wonders may serve a much bigger purpose.

"We believe they are indicators of the health of the ecosystem, because they specifically inhabit stable ecosystems," she said.

Because seahorses depend on the bay's fragile seagrass communities, the value of studying their populations is two-fold. Since 1950, seagrass habitat in Tampa Bay has dramatically declined, although improving water quality has led to substantial seagrass gains in recent years. Mapping seahorse populations may help scientists identify environmental factors associated with their presence and in turn, determine what habitat is healthy or not so healthy.

"We don't have a good idea of the status of their populations in Tampa Bay," said Dr. Ilze Berzins, Florida Aquarium's vice president of biological operations and veterinarian. "We don't know how many there are or understand the many ways their habitat may influence them. We don't know if conditions are improving or worsening. They can help us monitor our own backyard."

Because they are charismatic organisms, Masonjones believes they are an ideal "poster child" to rally support for protecting seagrasses.

However, habitat loss is not the only threat to seahorse populations, overharvesting contributes to their demise as well. Each year, millions of live seahorses wind up trapped in aquariums and millions more are dried and sold as collectibles to tourists, or crushed into powder and used as traditional medicines throughout Europe and Asia. Dried seahorses are believed to treat baldness, infertility, asthma and rabies.

"In 1995, over 20 million individual seahorses were exported," Masonjones said. "In 2000, the global consumption totaled over 25 million."

Scientists estimate that seahorse populations worldwide have declined 35 to 40 percent. This year, international regulations were put in place that restrict the export of seahorses, dead or alive.

Masonjones hopes her research in Tampa Bay will assist scientists in determining actions needed to protect wild seahorse populations around the world.

"Other studies have been done over the years looking at either habitats (seagrasses) or seahorse numbers, but there hasn't been extensive work looking at the combination of both issues (seahorses in their habitat)," she said.

Surveying seahorse populations involves spending long sun-drenched days in the field, combing seagrass beds with large rectangular nets. To speed things up, Masonjones calls on the help of volunteers. In the past year, 40 volunteers from the University of Tampa, the Florida Aquarium and the general public have assisted in her "seahorse round-ups."

Everything that comes up in the net must go into a bucket.

"It's important to count everything to determine the biodiversity of an area," she explained.

Masonjones records the location of capture and species of each animal, taking special note of any seahorses or pipefish. Then she marks the dwarf seahorses with a very small latex paint dot, which helps her track who lives where. Finally, she snaps a photograph of each animal before releasing them back into the open water, unharmed. Masonjones can study the photos later for additional information about each creature, minimizing capture time.

For each survey site, volunteers record the temperature, salinity, water flow and pH. The research team also identifies the type and condition of seagrass, and collects sediment samples that may eventually reveal whether contaminants play a part in offspring survival rates.

"We almost never see offspring... maybe one in every seven nets," Masonjones said. This is another mystery Masonjones hopes to eventually unravel - how the offspring are doing in Tampa Bay and where they are hiding.

Seahorses, like all members of the Syngnathid family, are unique because the males are the Mr. Moms of the sea; they give birth - a phenomenon that lured Masonjones into studying these fanciful creatures in the first place.

"There are few species in the world where males are specialized for carrying the offspring. Seahorses have the most elaborately adapted reproductive structure," Masonjones said.

Their small brood size, lack of extended parental care, low mobility and the fact that they mate for life, all contribute to the seahorse's vulnerability to environmental changes or overharvesting.

"If we don't work hard to preserve natural populations now," Masonjones said, "we won't have a population to study in a couple of years."

To volunteer for seahorse research in Tampa Bay, contact Heather Masonjones at 813-253-3333, ext. 3801.

Kristin Thoms is the public outreach assistant for the Tampa Bay Estuary Program and a freelance science writer.

Name:
Dwarf Seahorse,
Hippocampus zosterae

Range:
The dwarf seahorse inhabits most of the world's temperate and tropical coastal waters, including Tampa Bay, the Gulf of Mexico and waters surrounding Bermuda and the Bahamas.

Anatomy:
Diminutive in size, the dwarf seahorse measures about one to two inches from head to tail.

Seahorses are fish - they breathe with gills and swim with tiny delicate fins. Bony plates cover their bodies and serve as protective armor. The coronet, the bony structure at the top of the head, is nearly as distinctive as a person's thumb print. Male seahorses are unique because they have a kangaroo-like pouch called a marsupium for raising young.

All seahorses have a prehensile tail like a monkey and a small toothless mouth at the end of their elongated snout. Their eyes move independently of each other like a lizard's - always keeping one eye on prey and one eye on predators lurking nearby.

Depending on their environment, seahorses can change colors. In Tampa Bay, they can appear greenish to blackish.

Diet:
Seahorses feed on zooplankton - swallowing their food whole through their toothless mouths. As ambush predators, they wait, concealed among their surroundings until their prey (tiny zooplankton) move within striking distance. Then, with a lightning quick lash of their trumpet-like snout, they strike - sucking up their prey like a vacuum. Seahorses also hunt on seagrass blades which host a variety of delectable treats such as barnacles, tubeworms and amphipods (tiny crustaceans).

Habitat:
Seahorses, in general, are found in shallow and coastal water environments among seagrass beds, salt marshes, mangroves and, at times, coral reefs. In Tampa Bay, seahorses are most commonly found around Ft. DeSoto Park. They seem to prefer clinging to seagrass blades covered with epiphytic (plant) growth, which helps camouflage them even better.

Life Cycles:
The dwarf seahorse has a lifespan of about one or two years. Predators are few, but include crabs, small sharks and pelagic fish.

As monogamous animals, the same pairs mate throughout their lives. During mating, the couple brightens in color and displays an elaborate courtship dance. They intertwine their tails and swim harmoniously for as long as eight hours. The female then deposits about 100 eggs into the male's brood pouch. The eggs incubate for 10 to 30 days, or until the baby seahorses are big enough to survive on their own. Although pairs spend their days apart during pregnancy, the duo meets each morning and perform the tango, seahorse style. When the babies are ready to hatch, males hitch onto a blade of seagrass and begin to writhe to and fro, forcing the brood pouch open and allowing the tiny sea foals, or fry, escape and swim free. Dwarf seahorses typically give birth to 10 to 12 fry. Before dad has a chance to relax, his mate is there - ready to shovel more eggs into his pouch.