Board Thread:Questions and Answers/@comment-44260486-20191028120243/@comment-31797469-20191203203341

The chance is 1% without Torches.

With 11 Torches it is increased to 11%.

Island Skins Doubles the effective amount of Torches. 10 lit Torches and Island Skin provides a 21% chance.

Rarely, a Breeding Bonanza takes place, increasing the chance by 5%, 6% or 10%.