Grouper Moon Project Update

Nassau Grouper spawned in Feburary, starting 3 days after full moon. Photo by Jim Hellemn.
Grouper Moon team members spend time on each dive at the aggregation collecting data on behaviors, numbers, and size.
The Grouper Moon team gives a thumbs up before leaving for a dive.
A Nassau Grouper in regular coloration stands out among the rest in the aggregation. Photo by Christy Semmens.
Eggs were collected during spawning and then reared in a lab for a few days.

REEF scientists and volunteers just wrapped up another season of the Grouper Moon Project, a collaborative research effort with the Cayman Islands Department of the Environment (CIDOE). Our research focuses on Little Cayman, which has one of the largest (and one of just a few) known spawning aggregations of Nassau Grouper in the Caribbean. Over 4,000 grouper amass in one location for 7-10 days following winter full moons. Our team went to Little Cayman around full moons in both January and February this year (both because it was considered a “split year”, meaning the full moon dates were right on the line of predicting which month would be the strong spawning month). February turned out to be the big month, and spawning was seen over 3 nights starting 3 nights after full moon. Watch a short video montage of the aggregation and spawning action here - http://youtu.be/GwKVzPLgmbo

Since 2002, REEF and our partners at CIDOE, Scripps Institution of Oceanography, and Oregon State University have used a variety of research techniques from diver surveys to state-of-the-art technology to study this amazing natural phenomenon. The research has yielded ground-breaking results that have led to improved conservation for Nassau Grouper in the Cayman Islands. This year, we tested out some new techniques for collecting and rearing fertilized eggs (in the montage video you will see a diver swimming through a spawn cloud with a plastic bag). After collecting Nassau grouper eggs during the two nights of peak spawning, Scripps scientists and REEF Grouper Moon Project volunteers cultured the eggs at the Central Caribbean Marine Institute on Little Cayman. After one night, a subset of eggs were preserved for research on fertilization rates. After two nights, the eggs had hatched, and researchers were surprised to find larval Nassau swimming around the tank the next morning. Check out this video of larval Nassau grouper under the microscope - http://youtu.be/0Vph6LzH9IE

In addition to the research, REEF also is leading the charge on an educational program surrounding Nassau Grouper and spawning aggregations. Thanks to support from Disney Worldwide Conservation Fund, we have created an exciting K-12 education curriculum rooted in the link between healthy reef communities (including humans) and healthy spawning aggregations. See last month's REEF newsletter for more about the Grouper Education Program.

Want to learn more about the Grouper Moon Project? Lead scientist, Dr. Brice Semmens, recently gave a Perspectives in Ocean Science talk at Scripps Institution of Oceanography. The entire talk is online. Click here to watch! To see many more photos, videos, and stories from this year's work, check out the REEF Facebook page here.

Many Thanks! The Grouper Moon Project wouldn’t be possible without the dedication, passion, and financial support from many individuals, Cayman Island businesses, and foundations. It truly takes a village to pull off this conservation research project. In 2014, we especially appreciate the continued generous logistical support provided by Peter Hillenbrand, local lodging and dive operators Reef Divers & Little Cayman Beach Resort and the Southern Cross Club (especially Neil van Niekerk and the crew of the Lucky Devil for taking our team out in January), and Brac Reef Resort. Funding from the Disney Worldwide Conservation Fund supported field efforts and the Grouper Education Program. LIME Cayman Islands has provided support for the live-video feeds for the Grouper Education Project since 2012. Cayman Airways provided inter-island travel support. And the staff at Central Caribbean Marine Institute provided research space for the fertilized egg work. Thanks also to our scientists, volunteers, and partners who made this year's efforts possible - Adam, Alex, Brenda, Bradley, Croy, Guy, Hal, Ivan, James, Josh, Keith, Leslie, Laura, Lynn, Paul, Steve, and Todd. It's impossible to list everyone here - please visit the Grouper Moon page to see the full list - http://www.REEF.org//groupermoonproject. If you would like to support this important marine conservation program, please donate to REEF - https://www.reef.org/contribute.

Design by Joanne Kidd, development by Ben Weintraub