A consortium of coral experts published new guidelines that could help corals in the Caribbean adapt to warmer, more acidic waters caused by climate change. The guidelines are the first of their kind to offer a definitive plan for collecting, raising and replanting corals in an attempt to maximize their chances for survival.
The guidelines, authored by the restorations genetics working group of the Coral Restoration Consortium, were published online in the journal Ecological Applications. The consortium is a group of scientists, restoration practitioners, educators and concerned members of the public.
“What we’re proposing in this paper are short-term solutions to try and fill the gap between now and when we start mitigating climate change, so that we can maintain ecosystem function over the next few decades,” said Andréa Grottoli, professor of Earth Sciences at The Ohio State University and a co-author of the study.
“Coral restoration involves a lot of time, so the extent to which we can restore reefs is limited by time, effort, money, people and hours. What we are proposing are guidelines to think about which species we focus on preserving and growing, to give the reefs the best chance at long-term survival.”
Coral populations grow in a variety of environments, covering a range of temperatures, depths and light conditions, and tend to adapt to local conditions. That means that coral species in different environments should have genetic differences that allow them to thrive. The consortium recommended collecting corals from these different environments to capture as much genetic diversity as possible, then to raise corals in a nursery, where they can grow more quickly before being replanted on reefs in locations similar to their original environment — or in locations that may soon become similar to their original environment.
Corals are the foundation for reefs, which provide ecosystems for a variety of species and which can help protect coastal communities from shoreline erosion. Reefs also provide food and medicinal compounds. One study found they create $9.9 trillion per year in goods and services around the globe. But reefs worldwide face a variety of threats — foremost among them rising ocean temperatures and increased acidification because of climate change — and are declining, particularly in the Caribbean.
Grottoli, who is director of the Coral Bleaching Research Coordination Network, said the guidelines are meant to give conservationists, governments and non-governmental organizations practical, science-based plans for protecting and preserving coral in the Caribbean.
The guidelines prioritize coral species that can sustain a Caribbean reef’s foundation and that can help that reef rebuild itself long term. That means investing in corals that are resilient — that have proven successful in warming ocean waters, and that can reproduce in both nurseries and in the wild.
“The possibility of restoring all reefs globally is not realistic, and our capacity to restore reefs is going to be limited to some percentage of reefs,” Grottoli said. “Strategically, if we do that well enough, we can maintain enough species, enough genetic diversity, enough ecosystem function, for these reefs to survive so that there’s something to build from once we start mitigating climate change.”
Iliana Baums, lead author of the study, a professor of biology at Penn State University and chair of the Coral Restoration Consortium restoration genetics working group, called coral reef decline in the Caribbean “an urgent issue.”
“The Caribbean has experienced tremendous coral loss over the last few decades,” Baums said. “But few of the traditional guidelines for conservation, which tend to focus on vertebrates or plants, apply to corals. In this paper, we provide concrete guidelines for restoring coral populations, using the best available data.”
Grottoli said saving coral reefs — thereby saving the people, plants and animals that depend on them — will mean addressing climate change “at the tailpipe.”
“The coral are the building blocks for the reefs,” she said. “So if we maintain enough of them, the hope is that there’s something to build from once we start mitigating climate change. If we don’t, then it increases the probability that so little coral survive it becomes increasingly difficult to maintain coral populations and ecosystem function.”
Source: Ohio State University