State agricultural officials picked up a stowaway snake from Honolulu Harbor on Monday.

The reptile, which measures about a foot long, was discovered by workers unloading cars from a ship. Officials from the Honolulu Zoo identified the snake as a western terrestrial garter snake.

Inspectors from the Plant Quarantine Branch took possession of the snake at around 11:45 a.m. They also searched vehicles in the surrounding area and found no evidence of other snakes in the vicinity.

The discovery of the snake comes just a week after officials captured a 5-foot-long ball python found by county workers near a landfill in Hilo.

Snakes have no natural predators in Hawaii and pose a serious threat to the isles’ environment, according to the state Agriculture Department. Many species prey on birds and their eggs, increasing the threat to endangered native birds.

Individuals who see or know of illegal animals in Hawaii can call the pest hotline at 643-PEST or turn them in through the state’s amnesty program.