Chinook Salmon, Oncorhynchus tshawytscha (Walbaum 1792)

Currently stocked only in two landlocked lakes of SW VIC, temperate; freshwater; occurring in surface, open waters of these lakes.

D 11-15; A 15-20; P 14-17; gill rakers in first arch 23-27

Body fusiform, stream­lined, noticeably laterally compressed in large adults, deep; head conical; snout blunt, greatly extended, narrowed, and turned down at tip in breeding males; mouth terminal, slightly oblique mouth large, reaching back well beyond eyes; well-developed, moderately large, sharp teeth on both jaws, head and shaft of vomer, palatines, and tongue. Scales small, cycloid, 130-165 along lateral line. Dorsal fin origin at mid-body, square edged; relatively long, narrow adipose fin behind dorsal fin; caudal fin broad, emarginate to shallowly forked, tips pointed; anal with long base, square edged; ventral fins rounded, abdominal with axillary process; pectorals low, tip somewhat pointed.

To 150cm SL, commonly to 85cm.

Carnivorous feeding on small fishes such as galaxiids and pygmy perch but also consuming aquatic insects, crustaceans and some molluscs.

Young and adults generally spend most of their life at sea, migrating to freshwater to spawn but Australian populations are landlocked and spend their whole life in freshwater. O. tshawytscha do not spawn in the wild in Australia, populations are dependent on restocking.

Salmo tshawytscha Walbaum, J.J. (1792). Petri Artedi renovati. Part 3. Petri Artedi sueci genera Piscium in quibus systema totum ichthyologiae. Grypeswaldiae 723 pp. 3 pls [71]. Kamchatka, U.S.S.R.

M. Gomon, 2009