Fish species plays surprise role in aiding coral reef recovery

Dec 18, 2006

In a study that marks progress in understanding the basis of coral reef recovery, researchers have revealed the critical importance of a rare batfish, Platax pinnatus, in promoting the return to health of a disturbed coral reef overgrown with algae. The findings bring to light a previously unrecognized role for the batfish species, which had not been considered a significant player in reef recovery after overfishing.

In doing so, the study provides insight into the poorly understood—and potentially complex—forces that influence the state of coral reefs under ecological stress. The work appears in the December 19th issue of the journal Current Biology, published by Cell Press, and is reported by David Bellwood, Terry Hughes, and Andrew Hoey of the Australian Research Council Centre of Excellence for Coral Reef Studies at James Cook University.

The world’s tropical coral reefs are under threat from overfishing, habitat modification, and global warming. One of the most visible signs of a decline in the condition of coral reefs is the widely documented shift from a healthy state in which corals dominate to a weedy state in which algae (so-called “macro algae") dominate. It has been repeatedly demonstrated that this phase shift can be triggered by a loss of algae-consuming herbivores, especially parrotfishes and surgeonfishes. However, the critical question has remained: How can this coral-algal phase shift be reversed"

By simulating overfishing in large experimental plots on the Great Barrier Reef, the researchers in the new study intentionally triggered a phase shift to algal dominance on a healthy reef. They then filmed the reef’s recovery with remote underwater digital videos cameras. Remarkably, only two of the 27 herbivorous fish species present on the reefs had any significant impact on its recovery from algal overgrowth. What was most surprising was that the dominant browser was a rare batfish, a species previously thought to be an invertebrate feeder. Meanwhile, parrotfishes and surgeonfishes, which are the routine consumers of seaweed on coral reefs, were unable to reverse runaway algal blooms.

The study’s findings highlight the unexpected importance of a single rare species in the recovery of coral reefs, and potentially contribute to the identification and future protection of species groups that underlie the resilience and regenerative capacity of coral reef ecosystems.

Source: Cell Press

Explore further: Free the seed: OSSI nurtures growing plants without patent barriers

add to favorites email to friend print save as pdf

Related Stories

Reef fish arrived in two waves

Apr 10, 2014

(Phys.org) —The world's reefs are hotbeds of biological diversity, including over 4,500 species of fish. A new study shows that the ancestors of these fish colonized reefs in two distinct waves, before ...

Dissolving the future of coral reefs

Apr 10, 2014

Swimming through the liquid turquoise waters off the island of Viti Levu, Fiji, I am surrounded by iridescent fish of all colors, schooling around healthy branching corals. With a slight movement of my fins ...

A new ocean for the desert

Apr 01, 2014

As I let the air out of my buoyancy vest and slip under the water of the University of Arizona's Biosphere 2 ocean, I hear a steady hum reminding me of the machinery working behind the scenes to filter the ...

Recommended for you

Plants with dormant seeds give rise to more species

Apr 18, 2014

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Researchers successfully clone adult human stem cells

Apr 18, 2014

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

UAE reports 12 new cases of MERS

Health authorities in the United Arab Emirates have announced 12 new cases of infection by the MERS coronavirus, but insisted the patients would be cured within two weeks.