The strategy is to lure the alligator out using fish, chicken or some kind of bait and then get the alligator into a cage.
The alligator was first spotted Tuesday morning, and peeked its head out of the water during the ABC7 10 p.m. news. The alligator surfaced again Wednesday morning before going back in hiding.
WATCH: The search is on for the alligator spotted in the Humboldt Park Lagoon
It's unclear how the reptile got into the lagoon. The non-native creature was likely someone's pet that was released.
Alligator Bob, of the Chicago Herpetological Society, has been setting humane traps for the four-foot gator, who has been playing hard to get.
"We have some traps out there with assorted baits in it," he said. "They haven't been successful, but anybody who's ever fished a fish knows it's not a successful operation each and every time, especially when looking for a specific fish."
"I think it's smarter than we're giving it credit," said Sam Alcarez. "Alligators and crocodiles have existed for millions of years virtually unchanged by evolution. They've outsmarted nature time and time again. I think it's pretty easy for them to outsmart human beings as well."
Photographer Rencie Horst-Ruiz was out on the lagoon with a client around 6:15 a.m. Tuesday when her client spotted what they thought was an alligator in the water. Horst-Ruiz said when she looked down, she saw it too.
She called Chicago police, who then called Animal Care and Control. Animal Care and Control released a statement Wednesday saying they believe the alligator is a five-foot-long American Alligator that was once someone's pet.
"We want to ensure that the alligator, likely being kept as a domestic pet, is safely captured and brought to a facility where it can live in a suitable environment. It is illegal to keep an alligator as a pet in Illinois, and it is certainly illegal to release it into a public lagoon," said Kelley Gandurski, Executive Director of CACC. "People buy baby alligators thinking they are cute, only to realize that they will grow to be up to 500lbs (if male) and may become dangerous. Please do not buy an alligator, and if you have an illegal pet in Chicago, please contact CACC so that we can help you responsibly place the animal in a more suitable environment."
Throngs of onlookers have flocked to the Humboldt Park lagoon hoping to catch a glimpse of the gator, which isn't helping search efforts either.
"Every time he sees somebody he dives, so the more people that come here looking for him the less we're going to see him," Alligator Bob said.
So far, he said, the gator seems to be hanging out in the same central location. More traps are being set, but the mission could prove a test of patience for man vs. nature.
Experts believe it has only been in the lagoon for about a day or two and is used to being fed by its owner. It apparently hasn't started hunting any local animals, but will soon.
"After he's been here for a week or so he's going to go exploring all over, looking for a place to bask, looking for new food, a better place to sleep," Alligator Bob said.
It's unclear how long it will take to catch the alligator, but the plan is to take it to a zoo.
Onlookers have been told to stay away, but the novelty of the creature is magnetic for people like Beth Lacey.
"I've seen turtles and Canadian geese and all that, but nothing that looks like an alligator," she said.
Visitors are currently not allowed to paddleboat in the lagoon, but the company that rents paddleboats said that is unrelated to the alligator spotting; there is algae growing in the lagoon at the moment that makes paddleboating hazardous.
Visitors are being asked to stay away from the water until the alligator is recovered.
"We've had undercover conservation officers patrolling to keep an eye on things because it is an animal that could potentially cause problems," Alligator Bob said.
A separate police investigation into who released the alligator into the lagoon is ongoing.
It is a misdemeanor to have a pet alligator in the state of Illinois, and it is also illegal to release a pet into a public park.
This is not the first instance of an alligator let loose in the Chicago area.
In October 2018, a 4-foot-long alligator whose mouth had been taped shut was rescued from Lake Michigan near north suburban Waukegan. Authorities said the alligator wouldn't have survived for another couple weeks.
Within one month in 2011, two alligators were found swimming in the Chicago River. One, about 3 feet long, was found near the 3200 block of North Rockwell Street. Authorities said the alligator was likely a pet that someone turned loose. A slightly smaller alligator was found weeks earlier about two blocks north.
The Sun-Times Media Wire contributed to this report.