Imagine a vast forest of coral spread across the seafloor as far as the eyes can see. The warm, crystal blue Caribbean water is an aquatic forest filled with colors and teeming with fish. Few underwater tropical paradises like this still exist — but Scripps Institution of Oceanography graduate student Tali Vardi is hoping to change that.
Vardi is studying the elkhorn coral, known in the scientific community as Acropora palmata. It gets the name from its antler-like branches, which once dominated the Caribbean seafloor in waters from Florida to Venezuela. Today, only 5-10% of them remain. She goes to work underwater with transect lines, tape measures, billiard balls, a camera and quarter-size metal tags to collect information on the growth growth rates. She is collecting the data in order to build a mathematical population model for the coral species that marine resource managers in Jamaica and throughout the Caribbean hope can help them devise a recovery plan for the coral before the small remaining population disappears forever.
How fast is each population abundance declining or recovery? Will planting recruits lead to stable population size? If so, how many recruits must be planted? How many recruits are necessary to reach former density levels? Which populations should we save — those most at risk or those with signs of recovery?
These are the questions Vardi is seeking answers to in hopes of bring scientists closer to a solution for the rapid demise of elkhorn, which in 1996 was listed as threatened under the U.S. Endangered Species List, as well the entire Caribbean coral reef ecosystem.
Coral-eating snails, fireworms and damselfish like to munch on elkhorn coral, this along with temperature-induced coral bleaching, hurricane damage and poor water quality has stressed them out toward to near extinction.
Stay tuned for more information on Tali’s research and why she is using billiard balls at depth.