Understanding Dungeness crab fishing dynamics and rising whale entanglements Jameal Samhouri and Blake Feist NOAA Northwest Fisheries Science Center
How have California Dungeness crab fishery landings and activity changed over time and across the coast?
Office of National Marine Sanctuaries National Oceanic and Atmospheric Administration West Coast Region Data sources Ocean Acidifjcation Case Study: Dungeness Crab How will Ocean Acidifjcation What is Ocean Acidifjcation? Affect Dungeness Crab? Today, rampant burning of fossil Dungeness crab are an abundant and 1. PacFIN fish tickets and vessel lengths fuels, including coal, oil, and valuable species throughout national natural gas, is releasing too much marine sanctuaries along the West 2. Vessel Monitoring System (VMS) data carbon dioxide into the atmosphere. Coast of the United States. NOAA research shows that crabs in their early larval stages are vulnerable to low pH seawater. Years: 2009-2016 Spatial extent: US continental west coast Life Cycle of the Dungeness Crab Molting from one stage to the next and carrying fertilized eggs require a lot of energy, as does dealing with stress from global ocean change. Matched fish tickets to VMS locations within a specified time period Most vulnerable • Depth stages • Vessel speed • Specified “look back” window Annually, about 25% of human- caused carbon dioxide emissions is absorbed by the ocean, making the ocean’s chemistry more acidic. NOAA Research Shows Crabs are Vulnerable In lab studies, exposure to lower pH seawater decreases Dungeness crab larval development rates and survival. It also impacts the prey species—such as bivalves—which they depend This decrease in ocean pH over on. Complex modeling projects time is called ocean acidifjcation a 41% decline in Dungeness and it makes it harder for crab biomass and 30% loss in calcifying animals like Dungeness economic revenue in the next 50 crab to thrive. years due to ocean acidfjcation. http://sanctuaries.noaa.gov/education/oa
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