Jack Comparison 2-crop.jpeg

Image of two male coho salmon on a tray. The top is a 18 month old "jack" coho and the lower is a 36 month old.
Photo By/Credit

Daniel Spencer/USFWS

Media Usage Rights/License
Public Domain
Image
One of these males is not like the other one. "Jack" coho (top fish) only spend approximately 6 months feeding in salt water compared to 18 months in the ocean by a typical male coho. Jack coho make up roughly 5% of the population (varies between years) and are important genetic conduits between brood years.
Facility
Quilcene National Fish Hatchery
Species
Oncorhynchus kisutch
Subject tags
Anadromous fish
Fisheries
Fisheries management