Padre Island National Seashore asks anyone who finds a nesting sea turtle, sea turtle tracks or hatchlings to report it immediately: flag down a passing turtle patroller or a law enforcement officer, or call 1-866-TURTLE5.
The Park Service says Kemp's ridley sea turtles nest at Padre Island more than at any other location in the United States, and that the National Park Service has been part of the Kemp's ridley story since the 1970s. Nesting turtles there are protected, examined and tagged, and when it can, the Park Service invites the public to watch hatchling releases.
Closer to home, Sea Turtle Inc. on South Padre Island publishes a 24-hour emergency phone for injured or nesting sea turtles: (956) 243-4361.
A note on the season, because it changes what you are likely to be reporting. The Park Service page carrying the hotline describes nesting as a spring and summer activity, and that page was last updated on 18 February 2025. In late September you are far more likely to be calling about an injured animal than about a nest.
Sources: National Park Service, Padre Island National Seashore — sea turtles — https://www.nps.gov/pais/learn/nature/seaturtles.htm · Sea Turtle Inc., South Padre Island — https://www.seaturtleinc.org/