In addition to the mesophotic reef exploration and sampling objectives as part of Ryan Eckert’s Master’s thesis, we decided to incorporate aerial exploration and mapping into our research activities at Carrie Bow Cay. Specifically, our goal was to adapt the quadcopter aerial mapping procedure developed from Project CLOUD to a field-based reef mapping survey. The Smithsonian research station on Carrie Bow was an ideal location for reef mapping, as it has ample dock space for launching and recovery, it is surrounded by shallow water patch reef, reef crest, and seagrass habitats, and it boasts Caribbean water clarity and color. We developed the plan in conjunction with our Smithsonian Institution contacts, adding the production of a high resolution, georeferenced aerial map to our research deliverables.
 
Belize, however, has much more strict regulations regarding drone import/export and flight applications than the United States. With the appropriate permits and Customs inspections upon arrival in the country, we were successful in bringing our DJI Inspire 1 out to the station. Over several days, we conducted test flights to determine the optimal time of day resulting in the highest contrast and water penetration, while reducing sun glare off the water surface. Once we determined that 2:00 PM produced the best images due to reduced wind chop and solar glare, we began to systematically “mow the lawn” while taking downward-facing photos. We flew grid-like patterns over the surrounding reef, capturing photos of overlapping features to ensure downstream photomerging in image-editing software. To learn more about the aerial mapping procedure, visit the Project CLOUD page here.
 
Overall, we were able to capture the majority of the shallow water habitats surrounding Carrie Bow in five flights over three days. During the week, we also recorded GPS coordinates of island landmarks for downstream georeferencing in ArcGIS. Additionally, we were fortunate to be able to fly the quadcopter to the nearby Curlew Cay, a now-subsided barrier island to the south of Carrie Bow.
 
This mapping application has really pushed the boundaries of the protocol we developed for Project CLOUD. Carrie Bow is the first environment we have mapped that could not be fully captured over a single flight, or even over a single day. As a result, we generated nearly 500 images contributing to the overall map, far more than Photoshop can handle and merge at once. As a result of file limitations and slight differences in exposure and color across each flight day, we first had to merge portions of the photos together, and eventually those sections into a final map. With some creative color correction to match across seams, we produced two maps: a full-scale, map including all the habitat coverage, and a cropped, poster-format map. Both maps have been georeferenced using the GPS landmarks and therefore can be used for spatial analyses and for generation of media outputs within the Smithsonian. We are pleased with the adaptability of our mapping protocol to complex environments, and hope that these maps will be useful for informative applications of habitat differentiation and media outreach.

Post written by Michael Studivan.

After efficient and successful sampling at our 3 initial sites during the first part of the week, we made the trek another 15 miles offshore to Glover’s Reef Atoll to collect 60 additional Montastraea cavernosa samples (n=15 at each depth zone).  With these we will be able to make a preliminary assessment of connectivity between the Atoll and the main Meso-American reef.  We dove at Bev’s Garden, just off Long Caye, which had awesome wall structure with M. cavernosa populations that were ideal for our sampling needs. We were able to knock out all of our 60 samples in two dives and we used our third dive to explore Middle Caye Wall and scout for M. cavernosa colonies for future sampling. Both sites at Glover’s were beautiful. The walls had huge sponges and octocorals, Nassau Grouper, parrotfishes, and plenty of M. cavernosa and other sclerectinian corals. At Bev’s Garden we got to see two pods of Bottlenose Dolphin cruise over top of us. With luck, a trip back to Glover’s is in our future.
 
Finally, we spent our last day in the field exploring reefs near Carrie Bow Cay to find new sites to expand our dataset even further. We dove on three new (to us) reefs that looked very promising for our next trip back to the Carrie Bow Cay field station. We have packed up our 300 pounds of gear and are waiting for our boat ride back to Dangriga where we will stay the night before our trip back to Florida tomorrow. It’s bittersweet having to leave Carrie Bow after the week. It’s a beautiful place and a wonderful station to work at. We could not have been so successful without all the great support from our captain, Earl, station managers Scott and Lisa, and of course our wonderful cook Martha who made sure we were always well fed and ready to take on the day. So, although it’s sad to say goodbye and return back to real life, it feels great to have everything and more completely done and dusted.

​Check out our Flickr album for more images from the trip and stay turned for updates on Ryan's analyses of the coral samples collected during this mission.  Click on the embedded links to learn more about FAU Harbor and CIOERT.

Post written by Ryan Eckert.

The Voss Lab (Josh, Michael, Allie, Dani, and Ryan) is currently conducting field sampling in Belize in support of our NOAA CIOERT funded Mesophotic Project. We are based at the Smithsonian Institution’s field station on Carrie Bow Cay, fifteen miles off mainland Belize. The field station is completely powered by solar panels and a diesel generator for back up. During our stay on Carrie Bow Cay we have access to SCUBA cylinders, small boats, a flow through sea water system, wet lab and dry lab to facilitate our research. We have traveled out here from Florida to sample Montastraea cavernosa colonies from three Meso-American barrier reef sites. Previous research by Michael Studivan has identified a break in genetic connectivity between shallow (~60 feet deep) and mesophotic M. cavernosa populations (~130 feet deep). Therefore, we are back this year examining differences in M. cavernosa genotypes and zooxanthellae assemblages at additional depths.  These efforts will contribute to new grad student Ryan Eckert’s Master’s thesis project, and to our broad assessment of coral connectivity across the Gulf of Mexico, Meso-America, Cuba, and SE Florida.

Our current sampling design will assess four depth zones. At each of our three sites (Raph’s Wall, South Reef, and Tobacco Reef) we have back reef sites (~30 fsw), reef crest sites (~60 fsw), intermediate sites (~90 fsw), and mesophotic sites (~130 fsw). We are sampling 15 M. cavernosa colonies at back reef, reef crest, and intermediate depths at each of our reef sites (n=45 per reef, n=135 total). Small fragments (~5 polyps) of M. cavernosa are broken off from a colony with a hammer and masonry chisel. Before and after sampling colony photos are taken with 15cm parallel lasers to quantify colony size and qualitative record any visual differences. M. cavernosa fragments are preserved in TRIzol and frozen until we return to Harbor Branch and Ryan can extract DNA from the samples. Ryan will compare microsatellite markers among M. cavernosa samples to compare how genotypes may vary along the depth gradient of the reefs. Along with looking at M. cavernosa genotypes, Ryan will attempt to determine what clade types of algal symbiont zooxanthellae (Symbiodinium spp.) are found in M. cavernosa at the different depth zones. Zooxanthellae are endosymbiotic microbes and are what give color to M. cavernosa tissue. We have noticed many different color morphs of M. cavernosa along our reef sites in Belize, but whether or not these harbor variable zooxanthellae assemblages is an open question.   

After three days and eight SCUBA dives we've successfully collected all 135 samples across three depth zones at our main three reef sites. Because we have been so productive and efficient with our sampling, we had extra time to conduct additional surveys on our sites. We tested out (with mixed results) photo transects to make photo mosaic transects to analyze for relative abundance of coral species. Michael and Josh have also been used our lab drone to successfully produce a georeferenced aerial map of Carrie Bow Cay and the surrounding reef. 

Check out our Flickr album to view images from the trip.

Post written by Ryan Eckert. ​

Today, Alycia defended her Master's thesis to a packed room! Her research examined the effects of estuarine discharge and thermal stress on symbiont communities of the coral Montastraea cavernosa. As part of her project, she designed and constructed an ex situ aquarium system to expose corals to St. Lucie Estuary water containing discharges from Lake Okeechobee. In addition to submitting her thesis research for publication in a peer-reviewed journal in the near future, Alycia is continuing her work in the Voss Lab to examine the gene expression responses of the corals using RNA-Seq.

Congratulations Alycia!