Free range animals

[CodenameB]

Let's say I had some animals that I didn't care about the quality of. Instead of slaughtering them, what would happen if I put them on an island or something so they couldn't run away, and just left them there? Would they be able to graze on the forest tiles and keep breeding or would they need to be on grassland? Or would it simply not work at all?

Could I in theory just keep setting free all my old animals until the forests in my area are full of animals who keep breeding and grazing on grass?

(let's ignore the aspect of people taking them from the forest, I just want to know if it's theoretically possible.)

[sabinati]

they need to be on grassland, moor, or heath. even then i think the females will starve

[Phoen1x]

yeah, the females would probably be fine until they got pregnant, then no amount of grass can sustain them. I had a cow and a bull and stopped feeding them while I went offline for a while. When I came back the trough was empty, bull was fine but cow was a skeleton. There was still tons of grass around, too.