A patch of abnormally warm water has amassed in the North Eastern Pacific Ocean, and is moving its way towards British Columbia’s coastline. The characteristic shape of the affected water has caused scientists to dub it “The Blob”. You might be thinking to yourself that you accidentally stumbled onto a science fiction blog, but The Blob is very real, with equally real consequences for marine ecosystems.
![The_Blob_NOAA_April_2014](http://blogs.ubc.ca/communicatingscience2015w112/files/2015/09/The_Blob_NOAA_April_2014-300x204.jpg)
Sea Surface Temperature shows anomalies in the North East Pacific Ocean (http://www.climate.washington.edu/newsletter/2014Jun.pdf)
Oceanographers haven’t been able to point to a clear cause for the strange phenomenon, but they think it may be linked to the unusually strong El Nino we are currently experiencing. This summer, it has been attributed to several unusual marine observations.
A bloom of domoic acid producing phytoplankton has been seen within the blob, which has been linked to the death of approximately 30 whales that have washed ashore in Alaska. While it hasn’t been confirmed yet, toxins have been link to similar deaths in the past.
Zooxanthellae, a phytoplankton that lives in a symbiotic relationship with coral, has also been negatively affected by the blob. The warm temperatures cause the phytoplankton to become stressed, and expelled from coral reefs. Corals receive valuable nutrients from their phytoplankton partners that give them their radiant colours. Once the algae are expelled, coral reefs lose their colour, resulting in the occurrence known as coral bleaching. This has been seen this past summer in Hawaii, and leaves coral reefs with an increased vulnerability to environmental stressors. Given that coral reefs are areas of incredible diversity, containing up to one third of all marine species, understanding why the blob is occurring, and how long it will remain in the Pacific, is exceedingly important.
Due to the increase in thermal stratification throughout the blob, there is less vertical mixing, less nutrients being replaced from below which ultimately leads to less zooplankton to feed salmon. With a decrease in salmon’s energy source, scientists predict less juvenile salmon will be successful in their long trip from the estuaries out to the open ocean. Lower birth rates have also been predicted in whale species as well, given that they will need to expend more energy locating resources, leaving less available for reproduction and survivorship of young.
As warmer waters impinge along our coastlines, so do many marine species that are normally associated with warmer, tropical waters. Following the patch of warm water, Mola Mola (sunfish), triggerfish, and tuna have been spotted several times in B.C. waters, even as far north as Bella Bella.
Changes to marine ecosystems and population dynamics can be difficult to predict, given the complexity of the food webs. While the blob cannot be attributed to global warming, it does provide scientists with a unique opportunity to study the effects of a 2-4°C increase in water temperatures, and what may lie ahead for the oceans.
Sandra Emry