Levi Johnston -- Baby Overboard ... New Kid's a 'Water Sign'

Not sure she'll hunt like her daddy, but she may be a swimmer -- Levi Johnston's new baby made a huge splash during a water birth.

The former nearly-Palin-in-law and wife Sunny Johnston welcomed baby girl Indy Rae Johnston on January 11. With a name like Indy, you'd think she came out fast -- but we're told the 7.4 pounder took 4 hours to cross the slippery finish line.

If you're keeping score, this is Levi's third after ... Tripp with Bristol Palin and Breeze with Sunny.

Sunny and Indy are doing great, and Levi's determined to make her an outdoorsy chick -- she already has pink-camo gear.

Even Sarah Palin would be proud of that.