The san-reak were a type of very large animal native to San-Tarah.
The san-reak lived on an island across the Great Sea from where the Children of San-Tarah lived. Every year, before the cold season set in, San-Tarah's finest warriors would go there for the Great Hunt. A single san-reak was enough to feed the Children of San-Tarah for an entire cold season.
A great number of san-reak heads were displayed as trophies in the Meeting Hut where the Ruling Pack gathered. (GKN novel: A Good Day to Die)