What's the deal with snakehead fish and why are they called the ‘black masks’ of the seas?

Snakeheads, also known as "toman" or "black masks" have been reported to take over the waters of Calumpit, Bulacan.

According to an episode of "Born to be Wild," these creatures are considered an invasive species. They can eat fish bigger than they are. They are known for its scary-looking teeth, and are very territorial. They eat fish that comes in their way.

In the episode, Doc Ferds had his share of this "alien fish" that are slowly taking over some of the bodies of water in the country.

According to the episode, it is not normal to see the snakehead in the Philippines. They are native in Thailand and Malaysia.

But in Calumpit, anglers try their best to catch as many snakeheads as possible because they kill other fishes.

Christian Balagtas, an angler and guide in Bulacan, said when they go fishing, they usually try their best to catch a snakehead because they are considered as "pests" in the water.

Snakeheads, on the other hand, are well-equipped with survival skills and have yet to have a predator in the country. They are voracious eaters and very carnivorous.

Their bodies are very muscular and robust and they also have primitive lungs, which allows them to breathe out of water for as long as four days.

In countries like the United States, snakeheads are called as "nightmare fish" because they usually kill other endemic fishes surrounding them. — Ma. Angelica Garcia/LA, GMA News