THIS POST IS A BIBLIOGRAPHIC REVIEW OF THE HISTORY OF CORAL REEFS IN THE CONTEXT OF THE CONCERN THAT THEY NEED HUMAN INTERVENTION TO SAVE THEM FROM THE CURRENT WARMING CYCLE OF THE HOLOCENE THAT HAS BEEN ATTRIBUTED TO FOSSIL FUEL EMISSIONS.

HUMAN CAUSE: THE REAL ISSUE HERE IS HUMAN CAUSE BECAUSE WITHOUT EVIDENCE OF HUMAN CAUSE OF THE WARMING TREND, WHATEVER IMPACTS THE WARMING MAY HAVE ARE ALL NATURAL.

LINK: https://tambonthongchai.com/2021/11/09/the-issue-is-human-cause/

The climate change impact assumption may be hurting and not helping coral reefs because that single minded approach to understanding coral reef stressors may overlook the real issues in the understanding of the evidence of stress. This means that the climate change assumption as the overriding and sole issue in understanding coral health helps the climate movement to sell climate action but it does not help the coral reef. Known local anthropogenic coral reef stressors are seen in the bibliography below and all of these stressors have the potential to cause coral to expel their symbiotic algae, a condition identified as “bleaching” and generally but incorrectly interpreted as a form of death. Observed coral reef bleaching should be understood in this context and in terms of local stressors and not purely in terms of global warming. Also, even if it can be established that global warming is a coral reef stressor, it must be considered that the coral reefs we see today have survived the multiple and chaotic cycles of warming and cooling over the last 8,000 years of the Holocene described in a related post: LINK: https://tambonthongchai.com/2019/06/11/chaoticholocene/ . Not only that, they are still here having survived the last glaciation and prior to that they survived the Eemian interglacial that is known to have been much more intense of a warming event with temperatures 5C above current temperatures: LINK: https://tambonthongchai.com/2018/12/21/eemian/ quote: “In general, the Eemian is described as hotter than today with January temperatures 3ºC to 5ºC higher and July temperatures 2ºC to 4ºC higher but with large fluctuations in temperature between conditions hotter than today and colder than today. The Eemian is characterized by rapid fluctuations between warm and cold periods in multi-decadal time scales.” It has not been shown that the observed stresses in coral reefs that have caused algal expulsion are life and death issues for the coral reefs particularly so in the observation of recurrent mass bleachings that imply that a bleaching event is not the end of the coral. Some coral reefs may decline and others may grow, but the need for the human hand to be a coral nurse such as to prevent natural bleaching cycles is an intrusive form of environmentalism likely derived from the Bambi Principle: LINK: https://tambonthongchai.com/2020/11/15/the-bambi-principle/ . In the bibliography we find good evidence of the resilience of coral reefs in the paleo record going back through the whole of the Holocene and beyond. The mothering of coral reefs by humans in this context is either a Bambi environmentalism issue or a climate activism issue that needs a pathetic victim to sell its climate action agenda.

THE RELEVANT BIBLIOGRAPHY

1. Hughes, Terry P., et al. “Rising to the challenge of sustaining coral reef resilience.” Trends in ecology & evolution 25.11 (2010): 633-642. Phase-shifts from one persistent assemblage of species to another have become increasingly commonplace on coral reefs and in many other ecosystems due to escalating human impacts. Coral reef science, monitoring and global assessments have focused mainly on producing detailed descriptions of reef decline, and continue to pay insufficient attention to the underlying processes causing degradation. A more productive way forward is to harness new theoretical insights and empirical information on why some reefs degrade and others do not. Learning how to avoid undesirable phase-shifts, and how to reverse them when they occur, requires an urgent reform of scientific approaches, policies, governance structures and coral reef management.
2. Krueger, Thomas, et al. “Common reef-building coral in the Northern Red Sea resistant to elevated temperature and acidification.” Royal Society open science 4.5 (2017): 170038. Coral reefs are currently experiencing substantial ecological impoverishment as a result of anthropogenic stressors, and the majority of reefs are facing immediate risk. Increasing ocean surface temperatures induce frequent coral mass bleaching events—the breakdown of the nutritional photo-symbiosis with intracellular algae (genus: Symbiodinium). Here, we report that Stylophora pistillata from a highly diverse reef in the Gulf of Aqaba showed no signs of bleaching despite spending 1.5 months at 1–2°C above their long-term summer maximum (amounting to 11 degree heating weeks) and a seawater pH of 7.8. Instead, their symbiotic dinoflagellates exhibited improved photochemistry, higher pigmentation and a doubling in net oxygen production, leading to a 51% increase in primary productivity. Nanoscale secondary ion mass spectrometry imaging revealed subtle cellular-level shifts in carbon and nitrogen metabolism under elevated temperatures, but overall host and symbiont biomass proxies were not significantly affected. Now living well below their thermal threshold in the Gulf of Aqaba, these corals have been evolutionarily selected for heat tolerance during their migration through the warm Southern Red Sea after the last ice age. This may allow them to withstand future warming for a longer period of time, provided that successful environmental conservation measures are enacted across national boundaries in the region.
3. Pandolfi, John M., and Wolfgang Kiessling. “Gaining insights from past reefs to inform understanding of coral reef response to global climate change.” Current Opinion in Environmental Sustainability 7 (2014): 52-58. Global climate change is feared to lead to the collapse of living coral reefs, whose component organisms can respond in but three ways: migration, adaptation, and extinction. Because ancient reefs have been exposed to multiple episodes of environmental change, the fossil record provides an important resource for understanding the range of responses of coral reefs to climate change. Reef development has been slowed or stopped repeatedly in the history of life during periods of climate change. Whilst current conditions might be beyond some of the environmental ranges experienced throughout much of earth’s history, coral reefs have shown a remarkable resilience to past climate change. Their fate today lies in the interaction between climate change and local anthropogenic stressors that have devastated a large proportion of living reef ecosystems.
4. Barott, Katie L., et al. “Natural history of coral− algae competition across a gradient of human activity in the Line Islands.” Marine Ecology Progress Series 460 (2012): 1-12. Competition between corals and benthic algae is prevalent on coral reefs worldwide and has the potential to influence the structure of the reef benthos. Human activities may influence the outcome of these interactions by favoring algae to become the superior competitor, and this type of change in competitive dynamics is a potential mechanism driving coral−algal phase shifts. Here we surveyed the types and outcomes of coral interactions with benthic algae in the Line Islands of the Central Pacific. Islands ranged from nearly pristine to heavily fished. We observed major differences in the dominant groups of algae interacting with corals between sites, and the outcomes of coral−algal interactions varied across reefs on the different islands. Corals were generally better competitors against crustose coralline algae regardless of location, and were superior competitors against turf algae on reefs surrounding uninhabited islands. On reefs surrounding inhabited islands, however, turf algae were generally the superior competitors. When corals were broken down by size class, we found that the smallest and the largest coral colonies were the best competitors against algae; the former successfully fought off algae while being completely surrounded, and the latter generally avoided algal overgrowth by growing up above the benthos. Our data suggest that human disruption of the reef ecosystem may lead to a building pattern of competitive disadvantage for corals against encroaching algae, particularly turf algae, potentially initiating a transition towards algal dominance.
5. Buddemeier, Robert W., Joan A. Kleypas, and Richard B. Aronson. “Potential contributions of climate change to stresses on coral reef ecosystems.” Coral reefs and global climate change. Pew Center on Global Climate Change, Virginia, USA (2004). Human activities including development in coastal areas, over-fishing, and pollution have contributed to a global loss of over 10 percent of these valuable ecosystems. An additional 15 percent have been lost due to warming of the surface ocean, and climate change and is expected to further contribute to coral reef degradation in the decades ahead. Coral Reefs and Global Climate Change is the tenth in a series of Pew Center reports examining the potential impacts of climate change on the U.S. environment. It details the likely impacts of climate change over the next century to coral reef ecosystems both in U.S. waters and around the world. Report authors Drs. Robert W. Buddemeier, Joan A. Kleypas, and Richard B. Aronson find: • Increases in ocean temperatures associated with global climate change will increase the number of coral bleaching episodes. High water temperatures stress corals leading to bleaching . This term refers to the expulsion of colorful, symbiotic algae that corals need for survival, growth, and reproduction. While coral species have some capacity to recover from bleaching events, this ability is diminished with greater frequency or severity of bleaching. As a result, climate change is likely to reduce local and regional coral biodiversity, as sensitive species are eliminated.
6. Hughes, Terry P., et al. “Climate change, human impacts, and the resilience of coral reefs.” science 301.5635 (2003): 929-933. The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.
7. Bozec, Yves‐Marie, Lorenzo Alvarez‐Filip, and Peter J. Mumby. “The dynamics of architectural complexity on coral reefs under climate change.” Global change biology 21.1 (2015): 223-235. One striking feature of coral reef ecosystems is the complex benthic architecture which supports diverse and abundant fauna, particularly of reef fish. Reef‐building corals are in decline worldwide, with a corresponding loss of live coral cover resulting in a loss of architectural complexity. Understanding the dynamics of the reef architecture is therefore important to envision the ability of corals to maintain functional habitats in an era of climate change. Here, we develop a mechanistic model of reef topographical complexity for contemporary Caribbean reefs. The model describes the dynamics of corals and other benthic taxa under climate‐driven disturbances (hurricanes and coral bleaching). Corals have a simplified shape with explicit diameter and height, allowing species‐specific calculation of their colony surface and volume. Growth and the mechanical (hurricanes) and biological erosion (parrotfish) of carbonate skeletons are important in driving the pace of extension/reduction in the upper reef surface, the net outcome being quantified by a simple surface roughness index (reef rugosity). The model accurately simulated the decadal changes of coral cover observed in Cozumel (Mexico) between 1984 and 2008, and provided a realistic hindcast of coral colony‐scale (1–10 m) changing rugosity over the same period. We then projected future changes of Caribbean reef rugosity in response to global warming. Under severe and frequent thermal stress, the model predicted a dramatic loss of rugosity over the next two or three decades. Critically, reefs with managed parrotfish populations were able to delay the general loss of architectural complexity, as the benefits of grazing in maintaining living coral outweighed the bioerosion of dead coral skeletons. Overall, this model provides the first explicit projections of reef rugosity in a warming climate, and highlights the need of combining local (protecting and restoring high grazing) to global (mitigation of greenhouse gas emissions) interventions for the persistence of functional reef habitats.
8. Pandolfi, John M. “Incorporating uncertainty in predicting the future response of coral reefs to climate change.” Annual review of ecology, evolution, and systematics 46 (2015): 281-303. Coral reefs are considered one of the ecosystems most vulnerable to ongoing global climate change. However, geographic and taxonomic responses to climate change are highly variable, and fundamental aspects of key research approaches remain unresolved, leaving substantial uncertainty in our ability to predict the future of coral reefs. I review the ecological and evolutionary response of coral reefs to climate change in a broad temporal context, primarily focusing on tropical reef corals. I show critical gaps in our understanding that impede accurate prediction of future responses. These gaps include the response of past reefs to global change, the interpretation of coral response to thermal stress and ocean acidification, how corals and other reef organisms might respond evolutionarily, and our approach to evaluating response to climate in the context of multiple stressors. Reducing uncertainty by filling these gaps and by incorporating variation in geographic and taxonomic response will substantially improve our ability to model coral reef futures and manage coral reefs.
9. Hughes, Terry P., et al. “Climate change, human impacts, and the resilience of coral reefs.” science 301.5635 (2003): 929-933. The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming.