Isla Del Coco, Costa Rica
May 2021
Expedition Goals and Summary
As part of our continuing efforts to constrain the history of Oxygen Deficient Zones (ODZs) within the Eastern Tropical Pacific, we sampled coral cores, seawater samples, and coral tissue from Isla Del Coco, a remote Costa Rican island hundreds of miles offshore from the mainland. The location of Isla Del Coco makes it an essential node for any ODZ reconstruction, given that it lies on the southern edge of the oxygen minimum zone. As such, it is incredibly sensitive to an expansion or contraction of the southern margin of the ODZ. What is more, its remote location ensures that the coral cores from Isla Del Coco are not impacted by anthropogenic pollution or other coastal dynamics. These cores thus provide a unique opportunity to define changes in the influence and geographical extent of the northern Eastern Tropical Pacific ODZ over the 20th and 21st centuries.
In collaboration with the S/Y Acadia, the Smithsonian Tropical Research Institute, and the University of Costa Rica, postdoctoral researcher Nic Duprey and I collected coral cores, coral tissue, and seawater samples from 3 different reefs at Isla Del Coco. Together, we collected more than 10 coral cores, 30 tissue subsamples, and 30 water samples that will ultimately help us develop a full picture of the nutrient and climatic history of Isla Del Cocos.