Ocean acidification and hypoxia (OAH) is a change in ocean chemistry that is happening right here, right now. And, it is occurring at a faster rate than originally predicted. This phenomena has the potential to have profound impacts on living marine resources. Unfortunately, Oregon has the dubious honor of being the locale that first documented these impacts. In 2007, the Whiskey Creek Shellfish Hatchery had a massive hatchery failure due to acidic oceanic conditions (see the Case Study below).

What are ocean acidification and hypoxia?

Ocean acidification is a shift in chemical reactions that may pose significant problems for Oregon’s marine ecosystems. Hypoxia is a low or depleted oxygen environment that can cause marine life to die.

Ocean acidification and hypoxia are two ocean chemistry phenomena that are often coupled together, and both have the potential for profound impacts on living marine resources.

 

1.  Ocean water is rapidly becoming more acidic. In less than two centuries, ocean acidity has increased worldwide by 30%. This rapid change is a result of human-generated CO2 being emitted into the atmosphere, which is absorbed by the world’s oceans and increasing every year. CO2 absorption reduces the pH, causing increased acidity that reduces carbonate, a key component of sea water. Reduced carbonate can have detrimental impacts to marine life, particularly to organisms that use it in making their shells. Increasing ocean acidification (OA), has been tracked for several decades by hundreds of researchers worldwide. These long-term datasets positively correlate human-generated atmospheric CO2 production with increases in OA.

2. Coastal Oregon and the West Coast are particularly vulnerable to OA and Hypoxic Zones.The compounded effects of natural and human-generated factors increase the intensity of OA off Oregon, exacerbating the impacts from seasonal Hypoxic Zone formation. Naturally occurring seasonal upwelling of acidified deep ocean waters is a component of the Pacific Northwest’s ocean carbon chemistry processes.

In 2007, the Whiskey Creek Shellfish Hatchery, located in Netarts Bay, OR, suffered a substantial oyster larvae die-off. The hatchery produces oyster larvae for the commercial shellfish growers, and they were unable to provide their customers with the late-stage larvae required for a new crop. It was discovered that unusually acidic waters corroded the shells of the microscopic oyster larvae, causing the larvae and juveniles to die. The hatchery was eventually able to stem the die-offs by altering the chemistry of seawater pumped into their tanks to buffer against the low pH levels.

Oyster larval spat

Ocean acidification is a significant problem that is currently impacting Oregonians, and more widespread impacts are predicted for the future. Steps are already being taken to respond to our region's acute vulnerability to OA.  Oregon-based scientists and managers are rapidly expanding our understanding of ocean chemistry dynamics related to OA and hypoxia.

OAH Timeline

West Coast-Specific Ocean Acidification Resources:

Other Ocean Acidification Resources:

Want to Know More?
Contact: Caren Braby, Oregon Department of Fish and Wildlife
Phone: (541) 867-0300
E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.