From Texas Public Radio:
The San Antonio River Authority is spending $25,000 to trap a non-native rodent that’s wreaking havoc along the river banks.
The banks of the San Antonio River at first appear lush with vegetation, but once you look closely, you see the barren spots. That’s because the nutria, native to South America, have moved in. They can’t resist devouring the stems and roots of the plants that grow here.
So, the San Antonio River Authority has set 60 traps that span roughly 5 miles from Eagleland to the Mission Reach to catch the nutria which are sometimes called “river rats.”
Kirk Moravits is the natural resource management specialist for the San Antonio River Authority.
“So you can see we have a trap on the east bank of the San Antonio River right across from us,” Moravits says. “You can see right under the trap that there’s bare dirt, bare ground. There used to be vegetation that covered that entire area. The nutria eat that vegetation, they eat the base of the plant, they remove that plant—so that bank isn’t stabilized anymore.”
Nutria have beady eyes, orange teeth, a hump back and a long, rat tail. They’re just smaller than beavers. And some people even find them cute.
But Moravits says the nutria are burrowing into the banks of the river and that’s causing erosion. Nutria can eat 25 percent of their body weight a day in vegetation. Moravits says that they take away resources, food, and habitat from native species like raccoons, turtles and opossums.
“Some of our sparrows—the swamp sparrow likes to nest in those rushes and reeds. And that’s a habitat specialist; they require certain habitats, so they’re definitely in direct competition with those nutria,” Moravits says.