Threat of oxygen-poor ‘dead zones’ surfacing on BC central coast

The spectre of low-oxygen “dead zones” is surfacing along BC’s Central Coast, threatening the region’s rich marine ecosystems and fisheries.

Widespread hypoxia — when oxygen levels in the ocean fall below levels required by marine life — is being detected in the deep waters of Queen Charlotte Sound for the first time, said Sam Stevens, an oceanographer at the Hakai Institute and lead author of a new study.

Aggravated worldwide by climate change since warmer oceans generally hold less oxygen, marine hypoxia is now beginning to impact the sound, sandwiched between northern Vancouver Island and south of Haida Gwaii. Marine life, such as crabs, fish and a host of sea bed creatures like sea stars and anemones, begin to suffer from hypoxia when dissolved oxygen levels fall below two milligrams