From the AP, via the NYTimes:
A guy got on a JetBlue red-eye from San Juan to Newark with a couple of undeclared lovebirds in his carry-on. (I mean, he didn’t fill out the right form; I don’t know what declarations the lovebirds made.) Sure enough, one of them got out and made a break for it.
It all ended happily, though. The bird was caught and both were impounded until the unnamed passenger — who was not held — finishes the paperwork.