Two issues I've noticed with birds so far is that Parrot pirates have started spawning in the ocean, specifically in the ocean graveyard biomes. Additionally it appears come Hurricane season (and this has happened twice now) all bird sprites fail to load in. So while you may still yet see seeds or the new cormorant eggs spawn, you will not see the bird they came from.
Steps to Reproduce
Reproduce by sailing past sea graveyards in calm season and reaching the hurricane season to see the birds vanish.
This issue has been fixed in either a future version or updated in a previous version.