Purging pre-sapients doesn't seem to work?

[Askorti]

Has anyone stumbled upon the same problem? Had 3 pre-sapient pops on one of my planets, and despite first setting a hunting policy, and then an extermination one, nothing seemed to happen to them at all. Not even an acknowledgement that they're supposed to be purged.
Only after uplifting and then purging them as undesirables did I manage to get rid of them.

 

[Deuslinks]

Yeah have the same problem seems like the ai can purge them no problem as my gaia world filled up with them being forced out of a machine empire. however in my newest game nothing is happening to them either from being hunted or exterminated