I thought they were pidgeons?

There will be wildlife and indeed livestock similar to that which we get on Earth, but of course unique to Yliakum. Flocking birds would be a nice touch. It seems to me that there are a few ways these could be implemented:
The Easiest Solution: Every bird exists only for the player looking at it. It moves and flees without sending messages to the rest of the server, causing no network lag and no synchronisation issues. Downside is that nobody else sees the same birds in the same places as you, which is unrealistic.
The Main Idea: Allowing a flock of birds to be classified as one \'object\' and move/flock the same for everyone within viewing distance. The clever part here is that each bird within the flock could still animate and move independantly, however, its overall destination and movement is controlled by the server. This keeps relatively the same thing viewed by all players, aswell as reducing the amount of lag produced.
The Most Expensive: Every bird moves independantly, reacting to every player, and is controlled by the server. All players see exactly the same thing. This would be much more resource-intensive, and thus not really a viable option for poor ol\' Laanx (or most of our players either).