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  New Straits Times 11 Mar 07
Save our seahorses
 Chai Mei Ling

They are faithful to their partners, the males care for their young, and they are really cuter than what their Latin name denotes. Is there any reason why seahorses should not be allowed to live on? CHAI MEI LING writes.

WHEN the movie Junior starring Arnold Schwarzenegger as a pregnant scientist was released in 1994, people had a good laugh at the absurd idea of extreme role reversal.

But there is nothing laughable about pregnant male seahorses, because nature intended it to be that way. Seahorses, just like pipefishes and sea dragons, originate from the Syngnathidae family, where the males are the ones impregnated.

During mating season, which can happen once a month, female seahorses produce the eggs and transfer them to the males to be kept in a rotund, enlarged pouch on their chest. The males then fertilise, incubate, protect, osmoregulate and nourish the eggs for two to three weeks, after which they give birth to the young, or what are known as juvenile seahorses.

During each delivery, a father can produce up to 800 juveniles, which at 6-7cm long are miniatures of the adults. The young has a survival rate of 75 per cent when bred in captivity.

Seahorses are unique not just in such a way. Studies have shown them to be faithful partners. Marine Biology lecturer Choo Chee Kuang believes they are even more faithful than humans. “When the males are pregnant, female seahorses do not flirt around,” says Choo from Universiti Malaysia Terengganu (formerly Kolej Universiti Sains dan Teknologi Malaysia or KUSTEM).

Despite their harmlessness and vulnerability, these creatures are known as Hippocampus, or ‘sea monster’ in Latin. They have gills, which make them fish, a coronet on top of their head, and hard bony plates as body. Toothless, seahorses feed on small crustaceans like shrimps by suction mechanism. Their dorsal fin acts as the main propeller while the pectoral fin helps them swim sideways.

Out of 34 species in the world, seven can be found in Malaysia. They are the tiger tail seahorse (Hippocampus comes), spotted seahorse (H. kuda), barbour seahorse (H. barbouri), kellogg seahorse (H. kelloggi), three-spotted seahorse (H. trimaculatus), hedgehog seahorse (H. spinosissimus) and spiny seahorse (H. histrix).

The smallest seahorses in the world are the pygmies found in Indonesia — H. bargibanti and H. denise — which measure around 1cm. Another pygmy was recently discovered in the Indonesian waters but has yet to be named, says Choo.

The local H. Kelloggi, however, dwarfs over the pygmies as they can grow up to 20cm. The rest of the species in Malaysia are medium sized and are anywhere between 10 and 18cm.

Contrary to popular belief, seahorses are poor swimmers. They use their tail to grasp at seagrasses all the time and most species have very limited home range.

The tiger tail seahorses, for example, occupy just 1m square home range throughout their lifetime, says Choo.

As such, the survival of seahorses depends gravely on seagrass beds, just like the endangered turtle and dugong, which feed on seagrass.

Seagrass has a complex root system, which can extend up to 30cm into the seabed to fix and stabilise sediments. It also absorbs and recycles nutrients and oxygenates the water through photosynthesis.

The seahorses’ high productivity does not mean a thing because of their vulnerability to threats like by-catch in trawlers, pollution, and dynamite and cyanide fishing, which is still prevalent in Sabah and can cause habitat destruction. Around the world, seahorses are being exploited for the aquarium and traditional medicine trade.

“Malaysia acts as an entrepot for the seahorse trade. Seahorses sold in the country are imported from Indonesia and the Philippines, and we export mostly dried ones to Hong Kong, Taiwan and China,” says Choo.

According to him, fishermen in a village in the Philippines target only seahorses for their livelihood, selling them to countries such as the United States. “Do you know how much a seahorse cost here? A live one is sold at RM30, while the dried one in traditional Chinese medicine shops costs RM2 to RM3.

“Isn’t that sad? A father carrying up to 800 babies, the whole progeny, can die for that amount of money,” says Choo, adding that large harvest from by-catch in trawlers is the reason for the low prices.

In peninsular Malaysia alone, Choo and his team of researchers estimate that at least 500,000 seahorses are caught as by-catch each year.

Despite being listed in the International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species, the seahorse population has declined more than 50 per cent between 1990 and 2000.

“It’s a matter of time before they face extinction,” says Choo.

Development is another factor for the decline. Some resorts with chalets built on stilts over the sea have no proper drainage and irrigation system, and water from the shower is drained directly into the sea, feeding pollution to the seagrass.

And in southwest Johor, where the Tanjung Pelepas Port and warehouse industries are located, seahorses and other marine species are rapidly losing their fight for survival.

Coal-fire power plants built in the area in the last two years can raise the sea water temperature as water pumped in to cool the plants is discharged back to the sea. “As a result, marine larvae are killed and corals are bleached. Reefs start to bleach even at a 1-2 degree Celsius increase,” says Choo.

The seagrass at the Pulai River estuary, where Choo and his team conduct seahorse studies because of its diverse ecosystem, is located right in the middle of ongoing development.

Pulau Merambong in the estuary is the single largest intertidal seagrass bed in Malaysia. At 1.8km long from end to end and 38 hectares wide, it is the size of 35 to 40 football fields.

“However, there are not more than 400 seahorses left in a place this vast,” says Choo.

Industries have also caused the nearby Tanjung Piai to lose more than 50m of its shoreline in 2003 alone, and it is continuously eroding away.

“By the time we reach Wawasan 2020, Tanjung Piai will be gone. So will many other sea life,” says Choo. “It’s only a matter of time, at the rate we exploit our oceans.”

Still, Choo refuses to let his hope of saving the marine life be dimmed and is using the seahorse as an icon for marine conservation to save seagrass, which will also save other lives, through the Save Our Seahorses (SOS) organisation.

SOS recommends integrated coastal management plans to be implemented through a formation of a Pulai River Estuary Committee with participation from all stakeholders — biologists, engineers, politicians, business entrepreneurs, local communities and NGOs — to draw management plans for the estuary.

Choo’s team will be heading south to tag seahorses for a study on their movement from Wednesday to Saturday, and this exercise is open to the public who wish to help.

Apart from that, the team also needs volunteers for their seagrass mapping and monitoring, as well as invertebrates census projects.

“If humans can harm the environment, humans can also do the reverse. We can conserve it for the future generation,” says Choo. “Let’s give our seahorses a fighting chance at life.”
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