The chinook salmon averages about three feet in length and is the largest salmon. It is iridescent green to blue-green on the back and upper sides. The lower sides and belly are silver to white. The ﬂeshy gums of the lower jaw are black. There are small, black spots on the caudal (tail) ﬁn, dorsal ﬁn and adipose ﬁn. The breeding male is dark green-brown to purple. As in all salmon, an adipose ﬁn may be seen on the back close to the tail.
The chinook salmon is stocked in Lake Michigan. It is a native of the Paciﬁc Ocean, from Alaska to California. It was originally introduced to Lake Michigan by the Michigan Department of Natural Resources for sport ﬁshing and to help control the alewife population. It does not reproduce in Lake Michigan but has spawned successfully in some Lake Michigan tributary streams in Michigan and Wisconsin. It eats aquatic invertebrates and small ﬁshes.