Despite a very busy sampling schedule for the South Water Cay Marine Reserve biannual monitoring program, I was able to fit a little bit of my own work in at Carrie Bow Cay. On 5/17/2015, we had some down time due to some very rough seas that kept us off the forereef, so I took the opportunity to snorkel in the lagoon and collect a small Porites astreoides colony. My primary goal was to sample some tissue in order to assess my ability to obtain high quality DNA and RNA simply by fixation in ethanol and RNAlater. I was also interested in assessing the efficacy of my new corer tool, and the survival of a colony following transplantation and sampling.
The colony was approximately 25 cm2 and was located at approximately 3-4 m depth. It was the green morph of P. astreoides. I collected the colony and moved it to the backreef in front of CBC. I positioned the colony just east of the edge of the Thalassia bed in approx. 1 m depth. I did not epoxy the colony in place, opting instead to simply buttress it between pieces of coral rubble. I then used my new Elora 25 mm diameter corer to collect two cores from the colony. A shout out to Collin for helping me locate one of these hard-to-find tools on the internet. If found the corer to do a fairly decent job of extracting a piece of the colony, but not without some additional damage to the colony around the periphery of the corer. However, I do think using the corer is a better option than a hammer and chisel. I brought the cores back to the lab and fixed one core each in 95% ethanol and RNAlater within about 15 min of collection. I then stored the samples in the refrigerator.
Three days later, on 5/20/2015, I resampled the colony and again collected two cores for fixation in ethanol and RNAlater, respectively. Again, I was able to fix the cores within about 15 min of collection. The only difference this time was that the RNAlater I used was obtained on the island in the chemical storage room. I have no idea how old the reagent was; it was not dated.
I was also able to collect two colonies from the forereef on 5/19/2015, with a goal of transplanting them in the backreef to assess their survival the next time I’m on the island. I collected one colony from 10 m depth near the SWCMR transect at CBC-S-30, and another from 7 m depth near the CBC-S-15 transect. The deeper colony was about 25 cm2 and was the brown morph, while the shallower colony was also about 25 cm2 but the green morph. These colonies spent the night in buckets with flow through seawater until I was able to transplant them in the backreef the following morning. I placed the colonies adjacent to the earlier one, and also drove in a piece of rebar with flagging tape so I can relocate them in the future. The deeper, brown morph was placed behind, or west, of the rebar stake, while the shallower, green morph was placed east of the stake. Again, they were not glued, simply buttressed by rubble. I hope they survive and stay put!
Fig. 1. Colonies transplanted from the forereef to the backreef at CBC. (Left) Green morph of P. astreoides from 7 m depth. (Right) Brown morph of P. astreoides from 10 m depth.