pretty fun game, i like the concept a lot! i definitely think it would be improved with more efforts to communicate the game state with the player, like a summary available each day that shows you how all of the animal populations are changing (are they going up or down, or by how much). on a similar thought i think a population graph would be very cool!
i want to know more about the plants stats too, not only how much water they consume, but how much food each plant produces and how their life cycles work (i couldn't tell whether the trees died naturally or i was just killing them lol)
also at some point about 20 days in, animals stopped appearing in my shop. i assume it's because i placed every unique species, but it took me a bit to realize this and i wasted a few days just trying to reload the shop. i think it would be nice if you still got just as many items in the shop each day once you buy all the animals, maybe you just get more items/plants or maybe you can just buy a small population boost to specific animals. i know there's already an item that does that though.