Frenemies of the reef

Dr Slava Ivanenko examines coral for copepods.
Image: Gary Cranitch.


23 May 2010
The tiny, colored or semitransparent, one-eyed crustaceans that make up the subclass Copepoda may be among the most ecologically important animals in the world – but according to Dr Viatcheslav "Slava" Ivanenko of the Moscow State University, they may also pose a serious danger to coral reefs.
It's estimated that the oceans absorb approximately two billion tons of carbon each year. Copepods make up a large part of the biomass of the oceans, and so contribute significantly to the oceans' status as the world's largest carbon sink.
However, the news on copepods is not all good. Many copepods form parasitic relationships with corals and can damage coral reefs.
These copepods, however, have not been well studied in the world's oceans – Dr Ivanenko is one of very few marine biologists to focus on symbiotic copepod biodiversity. This group of copepods was discovered by coral aquaculturists.
"In French Polynesia and the South-China Sea, I found some taxa of copepods which we think could be quite damaging to corals. The parasitic copepods eat the coral hosts," Dr Ivanenko says.
"People from North America and Europe keeping aquaria had exchanged samples of an endangered species of Acropora – a very diverse genus of stoney corals, but they had problems from some particular species of copepods. Whole coral colonies died; it's like a disease. Interestingly, we know a little about the diversity of these copepods but almost nothing about their relationships with corals in the natural environment," he says.
Dr Ivanenko is studying the diversity and evolution of copepods, describing many new species and preparing specimens for DNA analysis. He hopes his work can inform ecological research.
"I am doing taxonomy but my goal is not only taxonomy. My task is to help people use information about small crustaceans living on the corals and other invertebrates, to identify them and to understand if they pose a danger to the reef. I have to attract the attention of ecologists. To my mind, it's quite important," he says.