AUSTIN (KXAN) — A mysterious animal swimming in Lady Bird Lake was recently identified by the Texas Parks and Wildlife Department as a nutria, which is a common rodent, often compared to beavers.

But they’re not always great neighbors. TPWD said in a post titled “Texas’ most unwanted plants and animals” that nutria eat aquatic vegetation and burrow, “which can lead to erosion and damage roads.”

Nutria can also be territorial and sometimes will lash out and become aggressive, according to Dr. Brianna Armstrong from Firehouse Animal Health Center.

Avoid nutria

Armstrong said she doesn’t often hear about nutria attacks on pets, but it can happen if people and/or their dogs are in the rodent’s territory.

“If you’re in their feeding grounds, or they have offspring with them, or you’ve cornered them, then sometimes they’ll respond and lash out and become aggressive,” Armstrong explained. “So those are kind of the scenarios where you want to be a little bit more careful and try to keep your pets away from them really at all times as much as possible.”

Armstrong said nutria usually startle easily, so if one is close by, it will typically get scared off by a loud noise.

Armstrong also recommends keeping dogs on close leashes and trying to avoid disrupting nutria in their natural habitats.

Risks, diseases from nutria

  • swimming nutria
    Nutria spotted in San Gabriel park in March 2023 (Courtesy Shari Quiroz)
  • swimming nutria
    Nutria spotted in San Gabriel park in March 2023 (Courtesy Shari Quiroz)
  • swimming nutria
    Nutria spotted in San Gabriel park in March 2023 (Courtesy Shari Quiroz)

Nutria can transmit rabies and a disease called leptospirosis, which is a bacterium that causes liver and kidney failure in dogs. It’s spread through urine, but Armstrong said water areas are easy places of transmission.

Leptospirosis is also zoonotic and can be transmitted from dogs to humans.

Not all vet clinics consider vaccines against leptospirosis part of dogs’ core vaccinations, so Armstrong recommends checking records for it.

Dogs should also be up to date on rabies vaccines.

Handling attacks

Armstrong said nutria have really long and piercing teeth, so if a dog (or person) does get bit, the wound could be anything from puncture wounds to lacerations that need to be sutured and should be treated immediately to avoid infection.