Failure to respond to a coral disease epizootic in Florida: causes and consequences

By 2020, losses of corals have been observed throughout Florida and into the greater Caribbean basin in what turned out to be likely the most lethal recorded case of Stony Coral Tissue Loss Disease. A Perspectives paper, published in the open-access peer-reviewed journal Rethinking Ecology, provides an overview of how Florida ended up in a situation, where the best that could be done is rescuing genetic material from coral species at risk of regional extinction.

Guest blog post by William F. Precht

A colony of the large grooved brain coral, Colpophyllia natans, infected by Stony Coral Tissue Loss Disease. The photo shows the progressive, rapid advance of disease, left-to-right, across the colony.
Image by William Precht.

Dredging projects conducted in association with coral reefs typically generate concern by environmental groups, resulting in careful monitoring by government agencies. Even though the aim of those dredge projects is to widen or deepen existing ship channels, while minimizing damage to coral reef resources, there are often the intuitive negative assumptions that dredging kills corals.

The recent Port Miami Dredge Project started as an uncomplicated case story. However, significant problems arose, caused by a concurrent and unprecedented coral disease epidemic that killed large numbers of corals, which was initiated following a regional thermal anomaly and coral bleaching event.

The coral disease, known as Stony Coral Tissue Loss Disease (SCTLD), was first observed in September 2014 near Virginia Key, Florida. In roughly six years, the disease has spread throughout Florida and into the greater Caribbean basin. The high prevalence of SCTLD and the resulting high mortality in coral populations, coupled with the large number of susceptible species affected, suggest that this disease outbreak is one of the most lethal ever recorded on contemporary coral reefs. The disease is still presently active and continues to ravage coral reefs throughout the region.

The initial response to this catastrophic disease by resource managers with purview over the ecosystem in Southeast Florida was slow. There is generally a noticeably short window of opportunity to intervene in disease amelioration or eradication in the marine environment. This slow response enabled the disease to spread unchecked. Why was the response to the loss of our coral reefs to a coral disease epidemic such a massive failure? This includes our failure as scientists, regulators, resource managers, local media, and policy makers alike. With this Perspectives paper, published in Rethinking Ecology, my intention was to encapsulate the numerous reasons for our failures during the first few years of the outbreak, reminiscent of the early failures in the U.S. response to the COVID-19 pandemic.

First, the Port Miami dredging project was ongoing when the coral disease epidemic began. Some managers and local environmental groups blamed dredging, rather than SCTLD for the coral losses, reported in the project’s compliance monitoring program. Second, this blame was amplified in the media, because dredging projects are intuitively assumed to be bad for coral reefs. Third, during this same time, the State of Florida prohibited government employees from acknowledging global warming in their work. This was problematic because ocean warming is a proximal cause of many coral diseases.

As a result, some managers ignored the well-known links between warming and coral disease. A consequence of this policy was that the dredging project provided an easy target to blame for the coral mortality noted in the monitoring program, despite convincing data that suggested otherwise. 

Specifically, the intensive compliance monitoring program, conducted by trained scientific divers, was statistically significant. SCTLD that was killing massive numbers of corals throughout the region was also killing corals at the dredge site. Further, this was happening in the same proportions and among the same suite of species. 

Finally, when the agencies responded to the outbreak, their efforts were too little and much too late to make a meaningful difference. While eradication of the disease was never a possibility, early control measures may have slowed its spread, or allowed for the rescue of significant numbers of large colonies of iconic species. Because of the languid management response to this outbreak, we are now sadly faced with a situation where much of our management efforts are focused on the rescue of genetic material from coral species already at risk of regional extinction.

The delayed response to this SCTLD outbreak in Southeast Florida has many similarities to the COVID-19 pandemic response in the United States and there are lessons learned from both that will improve disease response outcomes in the future, to the benefit of coral reefs and human populations.

Publication:

Precht W (2021) Failure to respond to a coral disease epizootic in Florida: causes and consequences. Rethinking Ecology 6: 1-47. https://doi.org/10.3897/rethinkingecology.6.56285