RFID in Japan reports that a fishery association in Japan is tagging shellfish to prevent theft from a protected fishing area:

Awabi, expensive shell fish, is one of the first kinds of fish to be RFID'd. They plan to tag all legally caught Awabi. Their theft prevention scheme is fairly simple -- if you find "Miyagi Awabi" without an embedded RFID tag, it is either caught illegally or fraudulent fish that was caught somewhere else.