Philippine authorities found nearly 500 endangered sea turtles – most of them dead – on two fishing boats last week. The discovery comes at a time of increased tension between China and the Philippines, both of which have been pressing their claims to parts of the South China Sea near the Spratly Islands.

Nine of the Chinese fishermen on board one of the boats have been charged with allegedly poaching the turtles, some of which were critically endangered Hawksbills. Also arrested were five Filipinos on a second boat. They are all being held in detention in detention as they await arraignment, according to a provincial prosecutor in Palawan. None of the fishermen could be reached for comment.

Poaching has long been a problem in the Philippines, a vast island country known for its amazing array of vibrant corals and sea life. Five of the world’s seven turtle species live the waters around the Philippines, but environmental threats and human infringement on their habitats have put their future in danger.

The Wall Street Journal spoke to Gregg Yan from the conservation organization WWF Philippines about the problem of poaching and how the latest row with China could go some way toward helping curb the illegal wildlife trade. Edited excerpts follow.

WSJ: How big a problem is poaching in the Philippines?

Mr. Yan: These poachers are but the latest in a long string of local and foreign violators. Most foreign poachers are Chinese, though some hail from Vietnam or Borneo. In 2009, we helped apprehend a 13-man crew who slaughtered 101 critically endangered Hawksbill Turtles in Palawan. Though few arrests ever lead to serious convictions, [that] case did.

It’s not just turtles, either. Last year, a Chinese vessel smashed into the country’s most productive reef, Tubbataha, destroying 3,902 square meters of corals. Worse, authorities found at least 2,000 dead scaly anteaters in the vessel’s holds. The list goes on hard and soft corals, giant clams, sharks, endangered Humphead Wrasse.

WSJ: Who is involved in it?

Mr. Yan: The illegal wildlife trade, estimated to yield at least $19 billion per year, has become a lucrative business for criminal syndicates because the risk involved is low compared with other crimes. Poaching syndicates flourish because there are presently no effective deterrents to the trade. High-level traders and kingpins are rarely arrested, prosecuted, and convicted for their crimes.

WSJ: Is it only foreigners or also locals?

Mr. Yan: With turtles it’s mostly driven by foreign poachers, but they usually have local guides who look for turtle hotspots or catch the turtles and [sell them] to foreign poachers. It’s poachers hiring other poachers.

WSJ: What’s driving the trade?

Mr. Yan: Especially with the high-value components, it’s foreign demand from an increasingly affluent Chinese community. You don’t want to generalize, but there’s a belief that it’s an aphrodisiac. They also use the turtle shells to make jewelry. This dates back to the Roman era. And the turtle eggs are also taken and eaten.

WSJ: What’s at stake if the poaching continues and what are some challenges to stopping it?

Mr. Yan: The Philippines is world’s second-largest archipelago after Indonesia, and we’re at least as rich in terms of marine biodiversity. We have some of the most productive coral reefs in the world. It’s almost impossible to safeguard 7,000 islands 24-7. There’s no way you can do it, even if you mobilize all of the armed forces.

WSJ: What is the WWF doing to help curb poaching?

Mr. Yan: One of my personal advocacies within WWF is to promote sustainable alternatives to curio items like sea shells, coral skeletons, horns, skulls and so on. It’s called the Better Choices campaign and hits everything from the seafood trade to the aquarium and aquaculture industries, all the way to traditional Chinese medicine.

WSJ: Will the high profile arrests of the fishermen for alleged poaching help?

Mr. Yan: It goes to show that we must work together, not as individual countries. There are animals that see no predator. They’ve been plying the seas between Malaysia and Indonesia long before these areas became countries and so to protect them we’re going to have to work as one. That means China working with Malaysia working with the Philippines and Vietnam. These animals are pelagic. If they’re only protected in one country but they swim into a country where they are not protected the whole species will be threated. It highlights the need for cross-country collaboration.

2014 Dow Jones & Company, Inc.