It may not look like much, but Australian biologists are growing increasingly worried that an invasive fish species named Anabas testudineus, or “climbing perch,” will soon invade their waters.
Climbing perch are one of the few fish species that can actually migrate between two bodies of water over land. They do this by using specialized spines on their gills to drag themselves across ground.
In addition to being highly aggressive and robust, climbing perch are also extremely adaptable. The species has been documented to survive days outside of water, can hibernate in mud for up to six months, swim freely in briny waters, and even kill predators by flexing their powerful gills in the throats of birds and predatory fish.
Watch the climbing perch “walk” below:
Individually, climbing perch are a menace. In large numbers, however, experts say the fish could devastate Australia’s native species. According to ABC News, scientists have been monitoring the spread of climbing perch from their native range in India and China to Indonesia and Papua New Guinea, and eventually to the Torres Strait just north of Australia. From there, only a small leap remains before the fish reach the Australian mainland.
“We’ve only found them on Boigu and Saibai islands, so these are the islands that are closest to Papua New Guinea,” said Nathan Waltham, a scientist with the James Cook University. “They haven’t been recorded any further south but the threat is if they aren’t managed… then they actually may move through the Torres Strait and move into northern Australia.”
The Torres Strait is filled with islands with a vital fishing industry. Fishermen bounce from one island to the next to find and sell fish, and experts worry that the perch will hitchhike its way across the islands attached to the bottom of fishing vessels. Researchers are currently educating fishermen about the dangers of climbing perch, but the fact remains that there is no way to eradicate the species from the islands. That means that without constant vigilance, the climbing perch will inevitably inch closer to Australia.
“Only with ongoing education and surveillance are we going to prevent climbing perch from arriving in northern Australia,” Waltham told The Guardian.
You can learn more about this strange fish in the video below: