More Evidence of Coral Reef Resilience!

Earlier today, WUWT carried a story about a coral reef that was presumed dead in 2003, is now teeming with life. Jim Steele adds to this below. – Anthony

Guest essay by Jim Steele

Director emeritus Sierra Nevada Field Campus, San Francisco State University and author of Landscapes & Cycles: An Environmentalist’s Journey to Climate Skepticism

In my essay, The Coral Bleaching Debate: Is Bleaching the Legacy of a Marvelous Adaptation Mechanism or A Prelude to Extirpation? I presented evidence from a synthesis of the most recent peer reviewed science that demonstrated coral reefs can be very resilient and the gloom and doom claim of climate alarmist Hoegh-Guldberg that “as much as 95% [of the world’s coral] may be in danger of being lost by mid-century.” is most likely biased fear mongering.

The literature review suggested coral should be very resilient to climate change because: 1) Coral had previoously adapted to warmer ocean waters than they now experience in the present and survived more frequent El Ninos over the past 6000 years. 2) Storms render the greatest mortality but coral quickly recover via “re-sheeting” also known as the Phoenix effect. 3) Coral adapt rapidly to climate change by shifting and shuffling their symbionts, acquiring new symbionts better adapted to the new conditions. 4) Much like trees and shrubs devastated by a fire, where new growth from protected buds can relatively quickly restore the forest; likewise coral can rebound from “cryptic polyps”.

While the Australian reported a balanced article comparing Hoegh-Guldberg’s gloom and doom to my more optimistic interpretations, the Australian Broadcasting Company’s Media Watch decided despite all the evidence for a more optimistic outlook, such an interpretation needed to be attacked. To protect Hoegh-Guldberg’s more catastrophic illusions, they dismissed my analyses, NOT with evidence, but via a “shoot the messenger” tactic. (Media Watch’s tactics were demolished here.) But now, as before, researchers are re-visiting what they thought were previously “dead reefs”, and they continue to find coral reefs are indeed highly resilient.

A recent NY Times article Coral Reef in Protected Area Shows New Signs of Life discusses the unpredicted rebound of Kiribati’s Phoenix Islands reef and Coral Castles.

“Everything looked just magnificent,” said Jan Witting, the expedition’s chief scientist and a researcher at Sea Education Association, based in Woods Hole, Mass.

“Last year, the whole place was holding its breath,” Dr. Witting said. This summer, it has sprung to life with plankton visible everywhere, he said, comparing it to a garden that is six times as productive as usual. “The whole ocean’s in bloom this year.”

Such reports are inspiring given researchers had declared Coral Castles dead in 2003. “On the floor of a remote island lagoon halfway between Hawaii and Fiji, the giant reef site had been devastated by unusually warm water. Its remains looked like a pile of drab dinner plates tossed into the sea. Research dives in 2009 and 2012 had shown little improvement in the coral colonies.”

But in 2015 it was “once again teeming with life.”

Researchers have been reporting similar recovery in reefs that were mistakenly thought to be dead or dying. At Northwest Australia’s Scott Reef, the upper 3 meters had lost 80 to 90% of its living coral and the disappearance of half of the coral genera. Yet researchers observed, “within 12 years coral cover, recruitment, generic diversity, and community structure were again similar to the pre-bleaching years.”

A similar long-term study in the Maldives observed a dramatic loss of coral during the 1998 El Nino but by 2013 the reefs also had returned to “pre-bleaching values”.

Similarly in a June 2016 article Great Barrier Reef: Survey off Townsville finds increase in coral despite recent bleaching they report on surveys of reefs near Townsville in the Great Barrier Reef’s central sector. Here NOAA estimated 33% of the reefs had suffered severe bleaching and only 10% of the reefs experienced no bleaching in 2015. This sector’s reefs had also suffered greatly from cyclone Yasi in 2011, yet “[s]cientists also found coral cover on seven of the reefs were at its highest levels since they were first surveyed 30 years ago.”

They concluded, “If reefs are not disturbed by anything then they do recover and we have seen that in the southern parts of the GBR [Great Barrier Reef].”

Indeed, in contrast to claims that global warming and ocean acidification are the biggest threat to coral, more optimistic evidence continues to mount. If undisturbed by destructive human practices, coral reefs are thriving despite climate change. Research published in the journal Proceedings of the Royal Society B show that coral reefs surrounding remote islands were dramatically healthier than those in populated areas that were subject to a variety of human impacts. The lead author of that research was encouraged to state, “There are still coral reefs on this planet that are incredibly healthy and probably look the way they did 1,000 years ago.”

Concerned with the El Nino induced bleaching event, Dr. Smith more recently reported protected reefs on “Palmyra did bleach in 2015, revealing haunting white landscapes”. But when an expedition returned to assess mortality and recovery in May 2016 she reported, “We sent team of 8 scientists to Palmyra for 6 days to assess the recovery of Palmyra’s coral reefs to the current warm water impacts of El Nino. On the first dive, it was hard to remember where the bleaching had been. The corals were full of color.” Although she warns this doesn’t necessarily mean Palmyra’s reefs are immune from future warming, “we are excited to learn from Palmyra’s reef communities to understand how the rates and patterns of regrowth and recovery influence resilience.”

Such resilience is exactly what the adaptive bleaching hypothesis would predict.

Jim Steele is author of Landscapes & Cycles: An Environmentalist’s Journey to Climate Skepticism