Wyvern

Wyverns were the Safeholdian ecological equivalent of Earth birds. There were literally as many species of wyverns on Safehold as there were types of birds on Earth.

All wyverns had two pairs of wings and one pair of powerful, clawed legs.

Varieties of wyverns included the homing wyverns, hunting wyverns, crag wyverns, and sea wyverns, as well as the largest known species, the king wyvern. 

Domestic use
Humans on Safehold used small wyverns to communicate via mail, as well as for the hunt, just as hawks were used on Earth. 

Pei Shan-wei's terraforming team deliberately changed the genetic make-up of the wyverns to make them more useful for that purpose.