April 10, 2015 — UConn marine sciences professor emeritus Peter Auster has been studying the ocean for his entire career. At a stage of life when many researchers would be hanging up their scuba gear, Auster still maintains an impressive worldwide portfolio of research. This spring, that portfolio included a two-week research expedition to Costa Rica's Cocos Island.
Regarded by scuba enthusiasts as one of the world's premier diving destinations, Cocos is a national park roughly 300 miles off Costa Rica's pacific coast. Because regulations ban all types of fishing around the island, and because the unique underwater typography brings a cold, nutrient-rich water welling up toward the surface, the waters around the island are frequented by a population of fish that is both dense and diverse. Those fish don't just draw tourists hoping for a keepsake photo, but scientists like Auster looking for information about how groups of fish interact.
"I'm interested in the role that species interactions play in affecting populations," says Auster, who has been trying to understand how the hunting behavior of one species may facilitate feeding by another. One example is the white-tipped reef shark, who are able to probe around and underneath coral looking for smaller fish to eat. When they do so, they end up flushing out prey that are often eaten instead by bluefin trevally, a fish that tends to follow the sharks.
"[The trevally] are essentially getting a subsidy in finding food," Auster says.