Hundreds of invasive fish removed from San Marcos River — why aquarium dumping is bad

SAN MARCOS, Texas (KXAN) — They have suckers, they're invasive and they're swimming through Texas waterways right now.

Earlier this month, Texas Parks and Wildlife (TPW) said university researchers removed around 406 invasive suckermouth armored catfish, also known as plecos, from the San Marcos River during a dewatering event at Rio Vista Park.

Information gathered from the caught fish will help nature experts better understand how to control the invasive species, according to TPW.

The Texas Invasive Species Institute said the suckermouth armored catfish, which is native to Central and South America, can grow anywhere from three inches to more than three feet in the right conditions.

Different species of the fish can be found in the San Antonio River, Comal Springs, San Marcos River, San Felipe Creek and the Brays and Buffalo Bayous in Harris County, according to the institute.

Outside of Texas, the institute said they are present in Florida, Nevada and possibly Wisconsin.

But how did they get into the San Marcos River in the first place?

TPW said suckermouth armored catfishes have been introduced to several bodies of water in Texas through aquarium dumping — when pet owners dump their aquarium wildlife, including fish, animals and plants, into natural bodies of water or flush them down the toilet.

Texasinvasives.org said when aquariums are dumped into the wild, "they can introduce disease or become serious predators, killing off local fish colonies, and damaging reefs and vegetation."

The organization described the suckermouth armored catfish as "voracious consumers" of plants and wood, and the species greatly contributes to erosion in infested areas. The fishes also can also cause banks to collapse, due to the deep burrows they create.

However, the website said there are more responsible ways to get rid of your aquariums, if you must. Options include finding a new family for your fish, selling or trading your fish and humanely euthanizing your fish. You can read more about those options online.