Atlantic salmon from fish farm in Washington

WASHINGTON - An Atlantic salmon caught near Kasilof in July had escaped from a private hatchery in Washington state, according to state wildlife officials.

The fish was the first documented Atlantic salmon in Cook Inlet, but the origin of the fish remained unknown until lab tests focused on its otoliths - small, rounded bone-like structures found in the inner ears.

The structures develop unevenly depending on the fish's growth rate, forming rings like those akin to tree rings.

The fish found off Cohoe beach had very even growth rings, indicating it had received regular feedings, as salmon raised in hatcheries and farms, according to Bob Piorkowski, invasive species program coordinator for the Alaska Department of Fish and Game.

Source: Anchorage Daily News