Sagay seahorses repopulate

In the past, the waters of the Philippines were teeming with seahorses. But today, the areas where they used to swim are now almost devoid of this marine creature. They have been overharvested.

But the good news: there are some areas where the population of seahorses are again on the rise. Thanks to the seven-year partnership between researchers and the local island community, the coral reefs north of Negros Island are once more abound with seahorses. The collaboration has successfully protected and replenished the wild population of seahorses.

 "At Molocaboc Island in Sagay City, Negros Occidental, divers assisted in scientific surveys of seahorse populations, technicians maintained seahorse breeding facilities, the local government's Bantay Dagat (sea patrol) enforced protection, and schools gladly embraced information and educations campaigns," said a press release disseminated by the aquaculture department of Southeast Asian Fisheries Development Center Aquaculture Department or SEAFDEC on its website.

The island is within the Sagay Marine Reserve, a marine protected area chosen by SEAFDEC as the project site to protect and revive the dwindling population of the tiger tail seahorse (Hippocampus comes).

After a standardized hour-long survey done by local divers during assessments from 2012 to 2013, an average of 4.6 seahorses were found. Dr. Shelah Mae Ursua, who collected DNA samples for genetic analyses, found low levels of genetic variations among the seahorses that confirmed a dwindling population.

"Over seven years of conservation efforts, the number of seahorses collected during surveys gradually increased to 18.7 individuals per dive in 2015, 30 between 2016 and 2018, and 34 in 2019," SEAFDEC reported.

This suggests, according to Ursua, a SEAFDEC associate scientist who led the Japan-funded project, "that the natural seahorse population can recover with the proper management of natural resources, particularly by minimizing human disturbances in their habitats and preventing the collection of seahorses."

Not only that. The local divers have also seen other fishes that "were visibly becoming more abundant in the reefs," Urusa reported.

Trade

The Philippines is home to 10 species of seahorses, according to the International Union of Conservation of Nature. Unfortunately, seven of these are designated the global conservation status of "vulnerable" due to threats from overharvesting, pollution and destruction of their coral reef habitat.

"Tens of millions of seahorses are traded every year — a scale that provoked global export controls for the 183 countries that are signatories to the Convention of International Trade in Endangered Species," states the IUCN.

Countries that trade in seahorses include Australia, Belize, Brazil, China, Dubai, Ecuador, India, Indonesia, Italy, Japan, Kuwait, Malaysia, Mexico, New Zealand, Pakistan, the Philippines, Singapore, Spain, Sri Lanka, Tanzania, Taiwan, Thailand, United Arab Emirates, United States and Vietnam.

Since 2004, the exploitation and trade of seahorses have been illegal in the Philippines under Section 97 of Republic Act 8550.

Threats

The seahorse, whose genus Hippocampus (hippo meaning, "horse" and campus, "worm") is placed in the family Syngnathidae. It has an unusual shape: snout like a horse, tail like a monkey and males have pouches like kangaroos.

The seahorse swims weakly, propelled largely by the rapid motion of its dorsal fin. Its food consists primarily of minute, planktonic crustaceans, which are ingested into a small mouth at the end of a long tube-like snout by a rapid intake of water.

From Canada to Australia, a species of two is found in most coastal areas with sea grass beds, mangroves, coral reefs, estuaries and lagoons.  The smallest species have fewer than 10 offspring. Just one-fourth-inch long when born, seahorse species grow to 2 inches to 12 inches.

Scientific studies have shown seahorses having no problem of breeding, but only one in a thousand will reach maturity.

But trade is not the only threat to seahorses. They are also threatened due to destruction of their habitats, primarily mangroves, seagrasses and coral ecosystems.

"Worldwide, over the past few decades an estimated half of all mangrove habitats have been destroyed; nearly 60 percent of coral reef habitat has disappeared, become degraded and/or fallen under imminent threat; and some 1,400 square miles of seagrass habitat has been lost," reported the Animal Welfare Institute on its website.

 "Such degradation — caused by coastal development, pollution, dredging, climate change, and destructive fishing practices that include the use of trawls, dynamite and poisons — are just some of the threats to the places seahorses call home," AWI added.