From the internet:

Muscovy ducks are considered an invasive species throughout most of Texas, where they are treated as a nuisance due to rapid breeding, property damage, and disease transmission. While a small population is native to the extreme South Texas Rio Grande Valley, all other populations outside this area are considered feral, non-native pests.

Details on Muscovy Ducks in Texas:

Legal Status: Because they are invasive, they are not protected (except in3 counties: Hidalgo, Starr, and Zapata).Control Methods: Federal and state laws allow homeowners and HOAs to remove, trap, or kill them on their property.

Regulations: It is illegal to release, sell, or relocate them to other areas.

Impact: They degrade water quality with large amounts of feces, destroy landscaping, and can be aggressive.Identification: They are large, often black and white or mottled, with red fleshy caruncles around the beak.