Sika were introduced from (probably) Japan. They are more similar to red deer than fallow, despite their appearance, and there are concerns about hybridisation where the two species occur together. On the Forest, Sika occur mainly near to Forest Row, where an ornamental herd escaped over twenty years ago. The animals that exist today cannot be the same ones that escaped originally but the herd has not increased to more than twenty animals nor has it spread very far. Sika are superficially similar to fallow and often mistaken for them: sika antlers are not palmate but pointed, stags have a pronounced mane and they have pale scent glands on the hind legs.