Dictionary of Ichthyology  

shachihoko = a Japanese folklore animal with the head of a tiger and the body of a fish (a carp). This animal was reputed to cause rain to fall so castles and temples often bear its image to protect against fire.

Okayama Castle, Japan from Wikimedia Commons: http://en.wikipedia.org/wiki/File:Okayamajou26.JPG

Canadian Museum of Nature