From a lovely woman/naturalist, Patty. She saw this beautiful fish in the tidepools and wanted help id'ing it.
Caught by local fishermen using "arte xávega", a traditional fishing technique involving small land-based dragnets.
Pacific Chub Mackerel caught from Shelter Island Public Fishing Pier. Just before photograph was taken, fish was placed in a fisherman's bucket. Fish seen gasping for air in bloody bucket water. Dark, wavy bars and green back very distinctive for species.