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@HEAD = New techniques for responding to coral bleaching in MPAs In May 2016, the MPA News staff had an opportunity to snorkel the 306-km2 Bar Reef Marine Sanctuary in northwest Sri Lanka. Located in a sparsely populated area of Sri Lanka and billed as having the most pristine coral reef in the country, the MPA has 156 species of coral. When we got there, it was all completely bleached. The third global coral bleaching event that has rolled around the world from 2014-2016 has wreaked havoc for coral reef MPAs (www.globalcoralbleaching.org). With climate change, this is likely the new normal. Coral reef MPAs — from small sites like Sri Lanka’s Bar Reef to large ones like the Great Barrier Reef in Australia — will experience bleaching more and more frequently in coming years. Some corals will recover from the bleaching events. An increasing number will not. It is a grim forecast. What if anything can coral reef MPAs do about this? @SUBHEAD = Managing for bleaching In 2006 the Great Barrier Reef Marine Park Authority published a report, Reef Manager’s Guide to Coral Bleaching (http://www.gbrmpa.gov.au/__data/assets/pdf_file/0013/4450/GbrmpaReefManagersGuidetoCoralBleaching.pdf). The report walks readers through four steps of managing for bleaching: (1) protecting resistance to bleaching, (2) building tolerance to bleaching, (3) promoting recovery from a bleaching event, and (4) supporting human adaptive capacity. Much of the report addresses the need to reduce stressors on reefs, such as overfishing and pollution — undoubtedly an important strategy. But with the third global bleaching event coming so close on the heels of the second global event in 2010, coral MPAs may be facing a larger, more severe, and more immediate threat than was envisioned when the report was written. It may not be enough simply to reduce stressors on coral reefs. Even relatively pristine reefs like the Bar Reef in Sri Lanka are being hit hard. Active, creative management of reefs will probably be necessary. In coming issues of MPA News, we will examine ways that coral reef MPAs can face the threat of bleaching. @SUBHEAD = “In a decade or less, the water will warm again” Here we present ideas from Austin Bowden-Kerby of Corals for Conservation in Fiji, who offered suggestions this year to the Coral-List listserv based on his work: “In Fiji we experienced our first recorded mass bleaching in 2000, with >90% mortality on Southern reefs. It was indeed tragic, but at the time I felt a bit encouraged by the few unbleached, resistant corals. However, that initial hope was quickly dashed to bits when crown-of-thorns starfish (COTS) ate virtually all of the surviving corals, quickly consuming their preferred species (Acropora, Pocillopora) before moving on to some of the less palatable ones. This happened even at sites with low COTS abundance prior to the bleaching, as the relative abundance went through the roof when most of the corals died. “We are once again experiencing a mass bleaching event at some of our Fiji sites, but this time we are doing something about it: 1. Predator removal (and weeding of seaweeds if needed) to save the corals that didn’t bleach; and 2. Collecting fragments of the unbleached branching corals to ensure they don’t succumb to external factors post-bleaching. We are growing these resistant corals in field nurseries to form a gene bank of the various species. The corals will be trimmed each year to prevent senescence and to create large numbers of secondgeneration fragments for out-planting back to the reef, within notake MPAs where possible. The goal is to create sizable patches of bleaching resistant corals that spawn, recombine, and spread their genetics and symbionts and thus offer some hope against future mass bleaching events. “This proactive strategy to give the reef a helping hand in this time of crisis can be applied widely to help the reef adapt. If any are interested, I can send the manual of the various nursery and out-planting methods. An idea discussed on Coral List by several list members recently was that of shading coral nurseries to prevent bleaching, Austin’s advice to that idea was: “Bleaching will be back. So unless you plan to plant your nursery-reared corals to sites where the water stays cooler during future bleaching events, you may be fooling yourself that you are restoring the reef. In a decade or less the water will warm again and these corals will only bleach and die. What makes a lot more sense would be to allow nature to take its course in your nursery, and to use this mass bleaching event as an opportunity to identify corals that are bleaching resistant. You can then re-do your nursery using these resistant corals. “Whatever restoration you do with those corals will be more permanent and will help build resistance to climate change. Pockets of healthy, bleaching-resistant corals, which have enough genetic diversity within each species to ensure successful spawning, would generate coral larvae that would then spread resilience throughout the wider reef system. Isolated corals would on the other hand be unlikely of spawning successfully. “A second strategy to protect the few corals that don’t bleach — from predators and from algal overgrowth — could make a big difference to post-bleaching coral survival and ultimately to reef recovery, while helping build resilience in the system. What a shame if the resistant corals that are so vital to the future of reefs end up as COTS food! A COTS removal program might be in order on many reefs right now.” For more information: Austin Bowden-Kerby, Corals for Conservation, Fiji. Email: [email protected] [end] We asked Austin to write more of his thoughts on managing and responding to mass bleaching: I am now on Christmas Island Kiribati in the dark heart of the present global mass bleaching crisis. The bleaching has passed and the corals have mostly died. An estimated 80-90% of massive and lobate corals have died, and virtually all (99.9999% ?) of all branching corals are now gone, especially the Acropora and Pocillopora which are so vital as habitat for small planktonivorous fish and post-larval reef fish. We searched extensively for three days in both inner lagoon and outer lagoon areas, reef front and passes, over shallow dead Acropora dominated zones of the shallow fore reef and the staghorn dominated mid and inner lagoon, and we could find absolutely nothing alive. The corals of the inner lagoon certainly must have been adapted to very hot water, but this event must have gone over that threshold. If some of these thermally adapted corals had been moved from the hot inner lagoon to the cooler outer lagoon, they might have survived. This is a possible lesson learned for other reefs preparing for unrecorded heat stress levels- to move the thermally adapted corals into less heat stressed waters, so that something survives. With this thought, I began searching the shallow reefs between the lagoon and the ocean, and we finally found a few surviving corals. Pocillopora formerly dominated the outer lagoon, with some colonies as big as a minivan, but we could find none of the species alive in that area. We finally found four Pocillopora colonies alive in shallow areas near one of two main passes, three very healthy and one half dead and still partially bleached, all surrounded by dead corals of the same and other species. Had these corals settled and grown there from larvae produced by heat tolerant corals of the lagoon, in areas where the temperature got just too hot? My hypothesis is that the pass area remained cool enough for these particular corals because they carried the resistance of their parents, while it killed off all corals that were adapted to the cooler waters normally found there. In a 1M deep enclosed lagoon pool right adjacent to shore we found two small living branches of a much larger dead colony of Acropora, a short branched, wave-adapted species. We also found a 10cm, bright blue, juvenile coral in the adjacent enclosed bay, again near shore in an area that would be heat stressed during normal years. This coral must have recruited during the mass bleaching and survived. Crown of thorns starfish were not seen, neither were Drupela snails. If any had existed before, they would have starved to death by now from lack of food! We set up our coral nursery in the area of the pass, within the Cook Island onservation Area MPA, and near where we had found the few surviving Pocillopora corals. We trimmed and planted branches from the wild corals. We were also able to pick up the rock that the juvenile Acropora had settled onto and bring that into the nursery. So we have four genotypes of Pocillopora, and two species, one genotype each of Acropora. This is better than nothing, but unless more individuals can be found, there is very little hope of recovery of the branching corals, as survivors would be too far from others for successful spawning, and as no coral reefs exist up-current of Christmas Island. Local extinction of many species of branching corals has most likely occurred, but much more work is needed before making that conclusion. We now need a project to fund this work and to propagate the surviving species in order to bring the branching coral species that did survive back from the brink. A similar strategy is ongoing in Belize, PR, DR, and other Caribbean countries for the endangered Acropora species. In 2009 we started a project in Belize at Laughing Bird Caye National Park, where all but one colony of staghorn Acropora cervicornis had died out due to several bouts of bleaching and associated coral disease. After searching the wider area for a month, we found 19 genotypes of the species, mostly as isolated mono-genetic stands unable to create larvae during spawning. We collected and propagated the species within two field nurseries and the projects continues through Lisa Carne and the Belize NGO Fragments of Hope. The corals have gone through several minor bleaching events since we began propagating them, and have fared well. We tested samples of all the coral genotypes and have found that they mostly have the heat tolerant clade D zooxanthellae, but some have sensitive clade A, but the coral is somehow able to protect the algae (see our 2012 ICRS paper). Thus far over 50,000 second generation corals have been replanted to LBCNP, with most fragments growing into large colonies and thickets of diverse staghorn coral, crowded with fish. With acres of restored reef, the functioning of the marine park as a fisheries reserve has increased, as this vital fish habitat has returned. Compared to other restoration sites in the region, we have found that nursery corals out-planted within the no-take reserve, have had much lower predation rates from Hermodice fireworms and Coraliophila snails than do corals out-planted to overfished reefs. With the only tree-like species of corals now ecologically extinct from most Caribbean reefs, the reefs have become like forests without trees…. and in spite of protection from hunting, many bird species will not return to deforested areas. Likewise fish recovery will be limited in areas missing the vital branching Acopora corals. The entire concept of MPAs restoring fish resources to their original numbers will not give the expected result for such reefs, as they represent damaged systems. Caribbean MPAs missing the natural extensive stands of Acropora should perhaps be excluded from data comparing the effectiveness of MPAs, as they are broken systems. Adding Acropora coral restoration to Caribbean MPAs seems the logical pathway to both more effective MPAs and to more effective restoration of the endangered Acropora species. For Kiribati and other devastated areas, a similar approach is needed. We have all the methods and tools in hand, all that is needed now is the partners and the funding. http://tedxtalks.ted.com/video/Coral-Gardening-Frontline-in-th https://www.globalgiving.org/projects/emergency-response-to-massive-coral-bleaching/