08/24/2010 02:47 pm ET | Updated May 25, 2011

Chicago River Alligator CAPTURED: 'Alligator Bob' Nets Out-Of-Place Visitor (VIDEO)

How a 3-foot-long alligator ended up in the Chicago River is a mystery--but his time in Chicago will draw to a close after Tuesday's capture.

The gator was initially spotted in the river Sunday, and animal control experts told the Associated Press they believe it was an abandoned pet.

NBC Chicago reports that "Alligator Bob," a man who has been involved in three alligator captures in the past 13 months, was able to net the gator under the Belmont bridge Tuesday morning.

Bob trapped the gator against some corrugated metal lining the bank under the bridge, according to the Chicago Sun-Times.

"He just kind of eased it into the net," John Archer, president of the Chicago Herpetological Society told the paper.

Bob, a Chicago Herpetological Society volunteer, captured a 2 1/2-foot alligator in the river earlier this month, the AP reports. That gator was presumed to be an abandoned pet as well.

Eight-year-old gator-spotter Caleb Berry told the AP Monday that he wasn't afraid of the gray-and-gold scaled alligator because it is "a baby."

Archer told the Sun-Times the gator would be quarantined and then taken to a sanctuary, likely in the southern U.S.

WATCH the gator swim the Chicago River:

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