The white ponies of Eriskay. The Eriskay Pony is a rare and critically endangered horse breed from Scotland in the United Kingdom. It is believed that this pony type is how Celtic and Norse ponies used to be, and the very remote location of the Outer Hebridean islands preserved this native horse. By the 1970s there were only 20 ponies left, today the population is around 300 Eriskay ponies in the world.