CHICAGO (CBS) — A reptile expert known as “Alligator Bob” is continuing his search for a 4-foot alligator in the lagoon at Humboldt Park, after the toothy reptile was spotted in the water on Tuesday.

A volunteer animal expert from the Chicago Herpetological Society, Alligator Bob set out humane traps overnight, after spending hours Tuesday paddling around the lagoon, trying to trap the gator. He said the reptile might be terrified to surface for very long, because of all the foot traffic in Humboldt Park.

Illinois Department of Natural Resources Conservation Police and Chicago Animal Care and Control teams also helped check the shores of the lagoon on Tuesday, but have not had any luck trapping the alligator.

It was first spotted early Tuesday morning. Chicago police and Alligator Bob have said someone might have been keeping the alligator illegally as a pet, and set it free in the pond when it got too big.

“People go to southern states, they buy a stupid little alligator, think it is adorable, and they bring it home. And it’s six inches long. The next year it’s two feet. In the next year three feet, and then it can bite you and tear some serious flesh,” said Alligator Bob. “Nobody has respect for the law, and it’s not the law so much as the respect for the animal. What are you going to do with it when it gets to 6 feet long? What are you going to do when it’s 8 feet long?”

Although it was spotted swimming around in the lagoon again around again Wednesday morning, Alligator Bob said it could take days to catch the reptile, because it hides whenever he gets close.

“When I get near him with a net or a noose or something, he’s – the closest I’ve got is 40 feet – so he’s scared,” he said. “Every time we got near him, he played the submarine, and went buried down. Then we can’t find him. The water’s too murky to see him. If it was clear, we’d have a better chance.”

Efforts to catch an alligator swimming in the Humboldt Park lagoon continues this morning. Multiple traps have now been set. Alligator was last spotted at 2:30am. @cbschicago pic.twitter.com/K5QAHMKbjM — Mugo Odigwe (@MugoOdigwe) July 10, 2019

When the alligator eventually is trapped, it will be taken to an animal sanctuary or zoo so it can be quarantined and examined by a veterinarian.

Chicago Animal Care & Control executive director Kelley Gandurski said, because the alligator isn’t indigenous to Illinois, it will need a warmer climate to survive long-term.

In a separate incident in October of 2018, CBS 2 reported a kayaker out fishing for salmon on Lake Michigan found a four-foot long American alligator.