Drew Harvell, a professor of ecology and evolutionary biology, is widely recognized for her work on marine diseases — specifically, the ecology and evolution of coral resistance to disease as well as evaluating the impacts of a warming climate on coral reef ecosystems. Harvell says the ARC Centre of Excellence for Coral Reef Studies report showing that higher water temperatures in 2016 caused the worst destruction of corals ever recorded on Australia’s Great Barrier Reef may be followed by devastating outbreaks of infectious disease.
Harvell says, “Although the Great Barrier Reef was badly hit, the epicenter of this 2016 event is actually in the middle of the Indo-pacific, at Palmyra atoll and Kiribati where temperatures reached four degrees about the seasonal baseline for over a month. Over 90 percent of corals died on many of those reefs.
“This is the worst bleaching event of the northern great barrier reef. Mid and southern sections were also hit with a 2002 event that caused mass bleaching and outbreaks of infectious disease. We typically do see outbreaks of disease following the bleaching events, because of the double whammy of the corals being stressed and warm temperatures favor infectious microorganisms.
“Outside magazine published an article called ‘An Obituary for the Great Barrier Reef.’ The event was bad, but the central and southern regions of the Great Barrier Reef are quite healthy, so that article was over-stated. You don’t call a forest dead just because 50 percent of the trees are dead, but it is an extreme event.
“It is useful to realize this is the third straight year in a row of record-breaking temperature. Each year from 2014-2016 was successively the warmest year on record, assuming this year will once again break records and now be the warmest year on record.”