An international team of researchers from James Cook University’s North Queensland campus discovered that the link between fish and corals may not be as strong as scientists had always assumed.
The lead author, Pooventhran Muruga, a PhD candidate at JCU, examined more than 4,600 reports on the relationship between fish and corals.
“It is undeniable that coral reefs are a fundamental habitat for reef fishes, providing them with shelter and food. Consequently, it is not surprising that, for more than four decades, there has been a broad consensus that reef fishes are associated with reef-building corals,” Muruga said.
“But, in a more in-depth analysis of the literature, we found that there is substantial variability within and among fishes and locations, and that, globally, the associations between fish and corals are weak.”
Professor David Bellwood, co-author of the study, stated that the results call into question assumptions about the strength and ubiquity of the fish–coral associations.
“I would caution against assuming a direct and ubiquitous relationship between the two,” said Professor Bellwood.
Co-author Alexandre Siqueira noted that the apparent weakness of the fish–coral associations, combined with the stability of some fish populations in the face of catastrophic coral loss, underscores the need to recognize that coral cover alone may not influence fishes as strongly as we thought.
According to Muruga, rather than a critical interdependence, fishes and corals may be two entities that coexist in a far more complex ecosystem.
“The results do not minimize the importance of corals on reefs, but they suggest that the relationship is more complex,” Muruga said.
“It underscores the need to look beyond the simple paradigm that more coral equals more fish and to recognise the complex processes that structure and maintain coral reef communities,” he concluded.
