In an effort to help a little bit with DM side stuff, I'm going to start a discussion on the types of animals and plants that are common to the island.  This is a discussion, and is purely subjective in nature.  If you disagree, please post!

The Southern Plains:
Plants;  Tall grass closer to the coast, lower shrubs towards the mountains.  Small copses of trees break up the plain and moor.

Major Herbavors:  Wild Horses:  These horses count as heavy horses, and have thick winter coats.
Carabou:  Usually migratory.  They stay to the north in the summer, and come south in the winter.

Marjor Carnivors:  Plains Cats:  Use Large Cat (Lion/Tiger) stats.  Black fur, with whit tufts on the jaw and ears.
Sea Wyverns:  Use young wyvern stats.  These are more prevalent along the coast.  They tend to roost in the small rocky rises offshore to the south.

This seems ok to me.