It's not a bug. Perhaps something to be modified later, in the final stages, but for now it is actually a good thing. No, you don't care, but I do not hold your apathy. But someone that wants to be told immediately whether their creatures are doing the right things would like it. If it fails, and they never reproduce, then I should go look at the tags I added. It just shows that there isn't code to differentiate what messages like these should go to the player and which should not. Thus you will know when any creature on your map at all gives birth, and when a youth becomes a grown up.
I use it because I modified fire imps to give birth. I like fire imps. I like a constant stream of them. But they are otherwise limited in supply... The side effect of this is that it will tell me when they reproduce, so I can tell I have magma long before I find it. I have been thinking of doing this to various chasm and underwater river creatures, because currently I have the problem of their populations dieing out almost completely (and in one case, completely) before I even find the river or chasm. It will tell me long before I reach these spots whether or not my creatures are reproducing successfully. If I want to monitor populations, I can do so, even without knowing how many there are, estimating by number of births, and timing of growing up.
So no... Not a bug.
[ March 12, 2008: Message edited by: Pickerel ]