An island base with no room for the mobs to spawn will prevent ALL events. The events will get announced but no one will show up. Not even the flying mobs. I tested this before the frost caves update which added the bat event so technically that coud be an exception but I don't have any reason to believe it is.

I started the base at a site which was completely under water before raising the ground, so you have to be careful to cover the entire area with your constructions in order to get a spawn free base. But it can be done.