Off the western coast of the United States, marine life in the Pacific Ocean has been inexplicably starving, dying, or disappearing. From 2015 to 2016, more than 6,000 starving California sea lion pups were found stranded along the coast, abandoned by undernourished parents who could no longer care for them. In Washington State’s Twin Harbors State Park more than 100,000 blue-footed Cassin’s auklets, a type of diving seabird, perished in a historic mass morality in 2015. In the Gulf of Alaska, researchers found 45 dead whales in 2015, a sharp increase from the average of eight whales typically found each year. Similarly, in nearby Homer, Alaska, more than 300 dead or dying sea otters washed onto beaches in 2015, five times the number that would be found in a normal year.
Animals have also begun to change their behavioral patterns. Thresher sharks, sun fish, skipjack tuna, and over 20 other species that normally reside in tropical waters were spotted in the Gulf of Alaska from 2013 to 2016. Further south, a pod of Pacific humpback whales was seen in Oregon’s Columbia River in 2016, well outside their natural range. The weather has also begun to act in unexpected ways. Warm summers in the Pacific Northwest and mild winters in Alaska broke records and sparked wildfires from 2014 to 2016.
Scientists believe that these ecological anomalies may have been caused in part by a pocket of abnormally warm water known as the blob centered off the Pacific coast. Since its discovery in 2013, the blob continued to expand through 2015 until it stretched from Alaska to Mexico, encompassing 3.5 million square miles, an area larger than the continental United States. Sea temperatures inside the blob rose up to 7 degrees Fahrenheit above average, a rapid and dangerous increase for marine ecosystems, which struggle to cope with temperature fluctuations of more than a single degree.
Because warm water holds fewer nutrients, a rise in sea temperature decreases the abundance of plankton, krill, and other tiny creatures that form the base of marine food webs. The lack of this critical food source has caused fish populations to decline and seabirds and marine mammals to starve.
To make matters worse, warm water inside the blob sparked a toxic algal bloom in 2015 that stretched for 2,000 miles and lasted more than six months. The bloom closed beaches, poisoned marine life, and led to the temporary closure of several fisheries, including ones for Dungeness crab, sardines, and razor clams, causing widespread economic impacts. The delayed opening of the Dungeness crab fishery alone cost the industry $48 million in 2015.
As the blob begins to recede and sea surface temperatures slowly return to normal, scientists are still struggling to pinpoint the exact cause of this ecological disaster. Some think that an atmospheric phenomenon known as the Ridiculously Resilient Ridge caused the blob to form by blocking storms, which normally mix and cool the ocean, from entering the region. Others think that the blob marks a shift in the Pacific Decadal Oscillation, a long-term cyclical ocean pattern similar to El Niño. Some think the blob will continue to recede, while others point to its longevity following the end of the recent El Niño event and argue that the blob is making a comeback.
While scientists are unsure if the blob was caused by climate change, they strongly agree that similar ecological disruptions will become more common in the future as the oceans warm. In the meantime, investments in atmospheric and ocean monitoring, as well as ecological and fisheries research, can help to develop better forecasting capabilities and baseline knowledge of marine ecosystems to better understand the next blob and predict how it will behave. Given the ecological and economic impacts of this event, the number of unanswered questions, and the likelihood of similar events in the future, increasing America’s capacity to understand, monitor, and predict ocean and climate system fluctuations and disruptions is needed.
Published in March, 2017, by the Joint Ocean Commission Initiative.