ATLANTA — August 21, 2014 (UPI) — Young coral and fish know a crummy neighborhood when they see it, or when they smell it, rather. According to new research, damaged reefs give off distinct smells — smells that say to a fish, don't set up shop here.
Damaged reefs generally begin with overfishing. When too many fish are removed from a local, seaweed (food for many small fish species) can grow on reefs unchecked. When seaweed takes over it begins to choke out coral. It also gives of a smell that warns fresh coral not to take root there. A damaged reef also colors the surrounding water with a smell that warns fish to keep on swimming. And as a new study by researchers at Georgia Tech suggests, it all combines to create a downward ecological spiral that even strong regulations can't counteract.
"If you're setting up a marine protected area to seed recruitment into a degraded habitat, that recruitment may not happen if young fish and coral are not recognizing the degraded area as habitat," explained study author Danielle Dixson, an assistant professor at Georgia Tech's School of Biology.