- Large black spots on the gill cover (neither Pacific Salmon nor steelhead have these)
- Large scales, and large spots on back, rarely any spots on tail fin
- No red stripe along lateral line, lower jaw hooked on mature males
- 8-11 anal fin rays
- Dorsal, ventral and tail fins may be eroded or worn from containment in net pens
Atlantic salmon are non-native to Washington, but can be found in the state's marine waters at several commercial fish farms, where the fish are raised for the seafood market in enclosed net pens.
Occasionally, some of these fish escape from their holding pens and may be caught by anglers and commercial and tribal fishers.
The Washington Department of Fish and Wildlife (WDFW) considers Atlantic salmon an aquatic invasive species, but there is no evidence to date that Atlantic salmon pose a threat to native fish stocks in Washington through crossbreeding or disease.
Anglers are not required to record Atlantic salmon on their catch cards, but WDFW encourages anglers to report where the fish are being caught using this online form.
Atlantic salmon typically measure 28 to 30 inches and weigh 8 to 12 pounds after two years at sea. They have a number of features to distinguish them from wild salmon:
- Large black spots on the gill cover. Neither Pacific salmon nor steelhead have this feature.
- The dorsal, ventral, and tail fins of Atlantic salmon may be eroded or worn from containment in net pens.
- The tail fin is flatter than the notched fin found on wild salmon.
For more information, and to see photo comparisons between Atlantic and wild Pacific salmon, visit the Atlantic Salmon identification guide.
On Aug. 19, 2017, a large number of Atlantic salmon escaped into Puget Sound when one or more net pens collapsed near the San Juan Islands. Cooke Aquaculture, the operator, informed the department that the collapsed net pen held 305,000 Atlantic salmon, but the exact number of escaped salmon was still undetermined as of Aug. 25.
Tribal fishers using beach seines and gillnets reported they had removed more than 1,000 Atlantic salmon as of Aug. 25. Cooke Aquaculture reported more than 100 recreational fishing boats were on the water in Puget Sound, the Strait of Juan de Fuca, and in several Puget Sound rivers where escaped fish were being observed.
Anglers are encouraged to catch as many of these escaped fish as possible, with no limit on size or quantity. However, anglers may only fish for Atlantic salmon in marine waters that are already open to fishing for Pacific salmon or freshwater areas open to fishing for trout or Pacific salmon. The escaped salmon should range from 8 to 10 pounds and are safe to eat.
Anglers looking to land Atlantic salmon must have a current fishing license and must also observe gear regulations identified in the 2017-18 sport fishing rules pamphlet.
The cause of the net pen failure is being investigated by the company and state agencies.
This is not the first time a large number of Atlantic salmon have spilled into Washington waters. Large escapes also occurred in 1996, 1997, and 1999.