Low oxygen levels are pushing fish into shallower waters, with potentially devastating impacts for fisheries and ecosystems.

Fish can drown. While it may not seem like it, fish do require oxygen to breathe; it’s just that they get what they need from the oxygen dissolved in water rather than in the air. Too little oxygen spells trouble for our finned friends, which have to move or else suffer ill effects.

Unfortunately, oxygen concentrations are dropping throughout the oceans. A new study out of UC Santa Barbara and University of South Carolina is the first to document more than a dozen species moving to shallower water in response to low oxygen conditions. The research, published in Global Change Biology(link is external), spans 15 years of surveys and measurements. The authors stressed the importance of accounting for the findings in fishery management and conservation, or risk implementing strategies wildly out of step with conditions under the waves.

Read more at: University of California - Santa Barbara

Blue rockfish were among the species that migrated upward over the course of the study. (Photo Credit: Southwest Fisheries Science Center Rov Dive Team)