• Family: Hiodontidae (Mooneyes)
• Other Names: Bony tongue
• Ohio Status: No special status
• Adult Size: Typically 12-15 inches, can reach 18 inches. Usually weigh 1 pound or less, can reach 2.5 pounds.
Mooneye are a very bright silver fish with a very large eye. They have sharp teeth on their tongue and jaws. The dorsal fin begins just in front of the front edge of the anal fin and has 11 or 12 rays. Mooneye have a fleshy keel or pointed edge to their belly from between the pelvic fins back to the anus. This keel does not have a row of scales folded over the edge forming a serrated saw like edge like the shads and herrings. Mooneye differ from the closely related goldeye by having a deeper body, dorsal fin starting in front of the front edge of the anal fin, shorter keel on belly, and no gold coloration to the iris of the eye.
Habitat and Habits
Mooneye are found in large rivers or lakes and are not tolerant of turbid (murky) waters from clay silts or industrial chemical pollutants. They are found in areas with swift currents, often below dams. In Ohio the mooneye is found in the Ohio River and its larger tributaries, particularly the Scioto River. Likely because of its preference for clear waters this species was far less abundant than the closely related goldeye over much of the 1900's in the Ohio River. In recent years the mooneye has become much more abundant in the Ohio River and the goldeye has become very rare in the Ohio portion of the Ohio River. Mooneye were also abundant in Lake Erie and the Maumee River up until the early or mid 1900's. Occasionally individuals are still found in Lake Erie primarily in spring in Sandusky or Maumee bays.
Reproduction and Care of the Young
Mooneye are thought to spawn in March or early April. Details of their life history are unclear but it is thought that they spawn in areas with swift currents and allow their eggs to drift with the current until hatching.