Chinook (king) salmon is the primary species targeted in California's ocean waters. The retention of coho salmon, however, is prohibited in all California ocean fisheries in order to protect Central California coast and Southern Oregon-Northern California coast coho stocks. Both stock complexes are severely depressed and listed under both state and federal endangered species acts.
The current drought in California is likely adding further stress to coho stocks, according to DFW officials. Thus, it is especially crucial this year to avoid any unnecessary mortality when handling and releasing coho salmon.
Taking the time to correctly identify each fish caught before removing it from the water can maximize survival of released coho. Furthermore, netting or dropping a fish onto the deck of a boat can cause scale loss and trauma that will likely reduce its chance of survival when released.
The most reliable method for identifying a coho is to examine the lower mouth and gums. On a coho, the gums at the base of the bottom teeth are grey, whereas Chinook gums are all black. Another way to distinguish a coho from a Chinook is to rub a finger along the fin rays of the caudal (tail) fin. Caudal rays on a coho will feel rough like the edge of a dime, whereas the fin rays on a Chinook are smooth.
On a king salmon (right), the teeth protrude from blackish gums and the lower jaw is sharply pointed. On a coho (left), the teeth protrude from greyish or whitish gums and the jaw is not as sharply pointed.
To avoid coming in contact with coho salmon, anglers are reminded to rig trolling gear to fish deeper as coho are more often found in the top 30 feet of water. Using larger lures that select for the larger Chinook salmon will also reduce chances of hooking a coho salmon.