Coral restoration is an important component in the field of ecological restoration, which is focused on repopulating reefs that have degraded overtime with more resilient corals. Reef degradation is attributed to the multiple, sometimes simultaneous, stressors that coral reefs are under. These stressors include temperature stress from global warming that leads to coral bleaching, an incredibly stressful state for corals. Stressors also include pollution, especially chemical and plastic pollution, and increased sediments from coastal development. The result of these stressors are things like disease outbreaks and mass coral mortalities. Reef Response researches best practices for coral restoration, incorporating citizen scientists, in an effort to mitigate and offset coral loss at the local level. We are incorporating cutting-edge experimental techniques for restoration and incorporating community involvement to replant coral around St. Thomas, USVI.
ABOUT OUR CORAL
Our nursery corals come from a variety of sources. Our branching corals are primarily acquired as "fragments of opportunity." This means we collect unattached fragments that have been created from actions that are both natural (like storms) or human-induced (like improper anchoring or boat groundings). We salvage these fragments and place them in our in-water nursery. Mounding corals are often acquired as small portions of corals still attached to the reef. These corals require more care and so they are brought into and maintained in our land-based nursery. Our final source of corals include those that have been taken off the reef in an effort to prevent them from getting diseased or to rehabilitate them after suffering from disease.
Our in-water coral nurseries at Reef Response are the foundation of our coral outplanting program. Fragments of opportunity are used to populate our coral nursery structures where corals cared for and monitored as they grow.
Once the nursery corals are large enough, we move them to reefs that are determined to be good locations for repopulating. These corals then are attached to the reef with cement or marine epoxy and are regularly monitored to make sure they remain healthy in their new location. Our monitoring program involves measuring increases in coral cover and changes in fish communities in response to coral outplanting.
In our land-based nursery, Reef Response is utilizing a novel technique in coral restoration known as “micro-fragmentation.” This technique works by fragmenting a piece of coral into 1x1 cm pieces. Because of a wound-healing response, these smaller fragments grow many times faster than larger pieces of coral.
We grow the fragments on small cement pucks until they fill out the diameter in approximately 6 months. At this point they can be either outplanted back on the reef or fragmented again to increase our brood stock. What is most exciting is the ability of fragments cut from the same piece of coral to fuse back together into one large piece. This greatly reduces the time it takes for a coral to reach sexual maturity and begin reproducing and helping to contribute even more coral to the reef community.
SPECIES WE WORK WITH
WE NEED YOUR HELP
Acropora cervicornis, or Staghorn coral, is a branching coral that once dominated Caribbean reefs. Populations across the Caribbean have significantly declined since the 1980's from disease outbreaks and continual increase of sea surface temperatures. This species was one of the first corals listed under the Endangered Species Act and is a major focus of restoration efforts.
Acropora palmata, or Elkhorn coral, is a quintessential Caribbean branching coral and an ecologically important species. This species is an "ecosystem engineer" that forms the basis of shallow coral reefs. It's large branches create complex reef structure, which provides essential habitat for reef fishes. Similar to the staghorn coral, elkhorn coral populations have drastically decreased since the 1980's. This species was also one of the first corals to be listed under the Endangered Species Act.
Dendrogyra cylindrus is also called Pillar coral because of its unique pillar-like structure. It can often be regionally rare, but was fairly abundant in the US Virgin Islands. Unfortunately, this species is highly susceptible to the devastating Stony Coral Tissue Loss Disease (SCTLD), which was first reported in St. Thomas in 2019. Since then, pillar coral populations have nearly vanished around the US Virgin Islands. Saving pillar coral from disease is a major focus of our land-based nursery operations in order preserve remaining genetic diversity of this species.
Grooved Brain Coral
Diploria labyrinthiformis, or the Grooved Brain Coral, is a large, bouldering stony coral endemic to the Caribbean. This species is one of the many brain coral species susceptible to Stony Coral Tissue Loss Disease. Genotypes of this species are housed in our land-based nursery to preserve remaining genetic diversity. Colonies of the grooved brain coral in our land-based nursery were collected from SCTLD threatened reefs and rehabilitated in our water tables.
Great Star Coral
Montastraea cavernosa is a stony coral found across the Caribbean and notable for its large polyps and color variations. This coral is typically a mounding species and provides important reef structure. Like many other species we focus on, this species is susceptible to Stony Coral Tissue Loss Disease. Colonies of this species in our land-based nursery were rehabilitated following SCTLD transmission experiments conducted at the University of the Virgin Islands..
Boulder Star Coral
Orbicella annularis, also known as the Boulder Star Coral, is a massive bouldering coral that grows so that a single colony has multiple lobe structures. This species is one of the most important reef-forming corals in the Caribbean. It is listed as endangered due to significant loss attributed to recent mass coral bleaching event and the emergence of Stony Coral Tissue Loss Disease. Boulder star coral was previously grown in our in-water nurseries but have since been relocated to the land-based nursery due to the emergence of SCTLD. This species is a major focus of our microfragmentation program in order to increase the growth of the genotypes in our water tables.
Mustard Hill Coral
Porites astreoides, or the Mustard Hill Coral, is a "weedy" Caribbean coral characterized by high abundance, quick growth, and high fecundity. This species is resilient to bleaching and diseases like the Stony Coral Tissue Loss Disease, however it does not contribute greatly to the structure of the reef due to its small size. We are testing how outplanting this species in conjunction with other more threatened species may facilitate their growth through positive species associations.
Symmetrical Brain Coral
Psuedodiploria strigosa, also called the Symmetrical Brain Coral, is a common bouldering stony coral found across the Caribbean. This brain coral is an important reef-building species because it is typically found in high abundance. Similar to the other brain corals, this species is susceptible to Stony Coral Tissue Loss Disease. Colonies of this species in our land-based nursery were collected from SCTLD threatened reefs or rehabilitated following disease transmission experiments in our water tables.
Report Signs of Bleaching or Disease
Reef Response along with our colleagues and collaborators are consistently monitoring the health of coral reefs around St. Thomas. But we can't do this all by ourselves! If you notice anything unusual on your snorkel or dive, we would appreciate if you take a moment to fill out a coral health report survey. This is crucial to inform us of where disease mitigation is needed. In addition, this information will be referenced in scoping for future restoration sites.