[2021] The new (1.3) animal population limiter ignores non-adult or reproducing animals, so now in a pen with a "max" of 12 animals, there are 46 lying around starving.

Originally posted by InfiniteImagination

It's not a bug, though! The code is behaving exactly as documented. (I guess I should've also added this to my initial post, but here it is: https://i.imgur.com/74CS9yz.png) The window literally tells you that it doesn't count non-adult or reproducing animals. My point is that the result of this design is that the automatic population control system is unhelpful and ineffective, but it seemed worth starting a discussion in case others had found otherwise.

Originally posted by froznwind

This is just my opinion but problem is the auto-slaughter automation is counting early pregnancies. They are normally hidden from the player but the automation is protecting the early-pregnant animals. With female tame animals nearly always being pregnant in Rimworld, it makes it impossible for the automation to slaughter enough females to maintain a stable population.