Low oxygen levels off coast raise concerns ‘Dead zones’ can kill marine life, harming seaside economies By Associated Press Share: PORTLAND — Low oxygen levels measured off the coast of Oregon and Washington are raising concerns of large “dead zones” that could decimate crabs and bottom-dwelling fish within them. The National Oceanic and Atmospheric Administration said last week that researchers have detected unseasonably low oxygen levels in a large area off the Pacific Coast, Oregon Public Broadcasting reported. Year after year of low oxygen levels beginning in the early 2000s led researchers to determine that Oregon now has a “hypoxia season” — just as it has a fire season — and this year’s hypoxia season has arrived far earlier than usual.