Coral Bleaching Currently Affecting 91 Percent of the Great Barrier Reef

Last summer, the Great Barrier Reef Marine Park Authority (GBRMPA) surreptitiously issued a report revealing that bleaching devastated 91 percent of individual reefs in one of the world’s marvels. Despite the fact that the proportion is smaller at the organism level and that some may recover, the report is disturbing because this should have been a year of regeneration, not further setbacks. A large La Nia event occurred last year, resulting in torrential rainfall throughout Australia’s east coast. Much of the region was flooded, including communities that saw a “one in a hundred-year” flood just a month after a “one in five hundred-year” tragedy.

The expected reprieve for the western Pacific’s coral reefs, whose principal threat is the heat associated with El Nio episodes, was one sliver of compensation. That has not been the case. Marine experts have been warning about the telltale white spots that form when corals become stressed and expel their symbiotic microalgae for months. The results of the GBRMPA’s yearly survey of the reef as a whole, on the other hand, have been kept under wraps, leading to speculation that their release may be postponed until after the Australian federal election on May 21, to avoid humiliating the government.

The study was issued without the usual fanfare, but The Guardian picked it up. Whether or whether allegations of pressure for a postponement are real, there’s little doubt this isn’t news the ruling coalition wanted people to hear before the election. “The surveys corroborate a major bleaching event, with coral bleaching reported at various reefs across all areas,” according to a statement released alongside the findings.

This is the sixth known mass bleaching episode, all of which have occurred within the previous 25 years, and the fourth since 2016. It’s also the first time widespread bleaching has happened during a La Nia, demonstrating that no year is exempt from the effects of climate change. Even if corals survive a large bleaching event, which occurs when temperatures drop too rapidly for them to rebuild themselves with new symbionts, the event leaves them vulnerable to future threats.

As a result, the next hot summer might spell the end for most of the reef, wiping off incredible numbers of species found nowhere else and tens of billions of dollars in tourism and fishing revenue. Scientists examined 719 of the system’s 3,000 designated reefs and discovered bleaching on 654 of them. Much of it was moderate (meaning less than 30% of the coral on the reef bleached) and part of it was mild near the northern and southern edges. The impact has been catastrophic throughout the heart of the reef, from the Whitsundays to near Port Douglas. Almost every reef studied has had at least 30% bleaching, and in most cases, more over 60%.

Because the northern end lacks infrastructure and the majority of the southern reef is offshore, this encompasses the key tourist attractions. Although the report’s authors have declined to comment, James Cook University’s Professor Terry Hughes has not been so reserved. Hughes, who created and oversaw the survey for many years before handing it over to the GBRMPA and the Australian Institute of Marine Science to handle jointly, voiced his feelings on Twitter. Overfishing, fertilizer runoff, and storms may all contribute to coral reef degradation, but marine experts believe that rising temperatures and ocean acidity are the most serious dangers. Both are caused by the burning of fossil fuels, a reality that the government – and Australia’s main media sources – has been anxious to downplay, especially given how much coal is sent across the reef.