RFK Jr. Double-Fists Snakes Having Sex

RFK Jr. was having a Steve Irwin moment when he grabbed 2 black snakes, bare-handed ... just as they were apparently in the process of getting it on!

You see in the video he posted on Tuesday, from Dr. Oz's house ... the U.S. Secretary of Health and Human Services walked over to the snakes and snatched them up.

The snakes were separated when he went to grab them -- double-fisting one in each hand ... but as he manhandled the reptiles, someone off-camera said ... "They're having sex." RFK Jr. laughed as he gripped their tails.

The snakes clearly weren't having as much fun as he was, because they kept trying to bite RFK Jr. as he messed with them -- and it looks like they even got a few nibbles.