Fish and Coral Smell a Bad Neighborhood: Marine Protected Areas Might Not be Enough to Help Overfished Reefs Recover
(Click to enlarge) Testing fish in a choice chamber A new study in Science showed that young fish have an overwhelming preference for water from healthy reefs. The researchers put water from healthy and degraded habitats into a flume that allowed fish to choose to swim in one stream of water or the other. The researchers tested the preferences of 20 fish each from 15 different species and found that regardless of species, family or trophic group, each of the 15 species showed up to an eight times greater preference for water from healthy areas.
(Credit: Danielle Dixson)
Pacific corals and fish can both smell a bad neighborhood, and use that ability to avoid settling in damaged reefs.
(From ScienceDaily) – Damaged coral reefs emit chemical cues that repulse young coral and fish, discouraging them from settling in the degraded habitat, according to new research. The study shows for the first time that coral larvae can smell the difference between healthy and damaged reefs when they decide where to settle.
Coral reefs are declining around the world. Overfishing is one cause of coral collapse, depleting the herbivorous fish that remove the seaweed that sprouts in damaged reefs. Once seaweed takes hold of a reef, a tipping point can occur where coral growth is choked and new corals rarely settle. Read the full story »