The zoo said the 3 1/2-foot-long mangrove snake was noticed missing from its enclosure inside the JungleWorld exhibit Wednesday.
Officials said the snake is believed to have slipped through a mesh vent cover and is likely still inside the JungleWorld area.
Mangrove snakes are mildly venomous, but zookeepers said the serpent is not likely to pose a threat to guests. The species is known to be timid and active at night, when the zoo is closed.
A sign was posted outside the JungleWorld exhibit warning visitors to be on the lookout for the snake, but officials said members of the public are unlikely to encounter the animal, and that the signs were posted out of an abundance of caution.