Lee County emergency personnel say Jack May was visiting Florida with his family when he was attacked.
May's brothers say he was in thigh-high water at the time of the attack.
Although he blacked out briefly, the NBC affiliate reports the teen was able to limp back to shore where his mother wrapped his foot in bandages.
May's brothers told the station the teen was actually laughing about the bite.
May and his family were expected to return to Denver on Saturday.
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