A Hurricane Provides Insight On Coral Resiliency

Look what turned up! A coral tree that was swept away by Hurricane Irma or Maria from the Flat Cay coral nursery USVI, was found by a fisherman off shore of Farmers Cay in the Bahamas. That fisherman contacted Kemit-Amon Lewis at The Nature Conservancy in St. Croix who in turn contacted Dr. Marilyn Brandt at the University of the Virgin Islands. Amazingly, the corals are still alive after experiencing such extreme conditions. This is important information and a testament to the resiliency of this genotype.

Colin Howe, Masters of Marine and Environmental Studies candidate at the University of the Virgin Islands, has been working closely with The Nature Conservancy and UVI to help care for and foster the coral nurseries established in the St. Thomas/St. John district. The coral fragments on the tree found in the Bahamas are of the naturally occurring hybrid Acropora prolifera or commonly known as fused staghorn coral. Out of over 60 coral restoration programs in the Caribbean, UVI is to one of a select few coral restoration organizations to incorporate this hybrid as part of their reef restoration efforts. Each fragment on the tree is genetically distinct, created from natural synchronized spawning events between the parent species, staghorn and elkhorn coral. Housing genetically distinct hybrid corals allows researchers at the University to observe and compare how this coral responds to environmental changes. In recent years, researchers have observed an increasing population of this hybrid in the USVI. 

 Colin Howe outplants coral branches from one of the St. Thomas nurseries.

Colin Howe outplants coral branches from one of the St. Thomas nurseries.

The parent species of A. prolifera (the staghorn and elkhorn) have been critically diminished here in the USVI waters. It is estimated that 90% – 95% of their populations have been eliminated due to a variety of reasons including human and natural causes. One theory explaining the increasing abundance of A. prolifera (fused staghorn) is that the expansion of this unique species was made possible through the loss of the abundance of the parent species. When both parent species spawn, they release gamete into the water column simultaneously. With a low population of the parent species it is more likely they reproduce between each other, rather than within their own species. This could explain why there is such a high abundance of A. prolifera coral in the Territory. 

Hybrid organisms are known have difficulties surviving in the wild, however, A. prolifera appear to be resilient under local conditions. 

Read more about coral restoration efforts in the Territory 

Coral Nurseries Are a Species Salvation

Making Coral Babies for the First Time

A Turning Point for Virgin Islands Coral

 A fisherman in the Bahamas found a coral tree from St. Thomas that was swept away during Hurricanes Irma or Maria

A fisherman in the Bahamas found a coral tree from St. Thomas that was swept away during Hurricanes Irma or Maria

This discovery of our corals found alive in the Bahamas infers how resilient to extreme conditions the fused staghorn hybrid coral is. It may potentially be used as a resilient  species to help reestablish coral reefs.
— Colin Howe
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