Sampling has been going very well and my freezer is beginning to be stocked with preserved samples. As expected, fish and algae are more common on the northern ridge and corals and sponges are more common in the central ridge. We have explored two sites that were not dived last year and were surprised with the number of Agaricia and X. muta samples.
Note: For photos from the trip, check out our Flickr. All Pulley Ridge 2014 posts are from Michael Studivan Sampling has been going very well and my freezer is beginning to be stocked with preserved samples. As expected, fish and algae are more common on the northern ridge and corals and sponges are more common in the central ridge. We have explored two sites that were not dived last year and were surprised with the number of Agaricia and X. muta samples. What’s interesting about PR is that it’s not what you would consider a typical coral reef. Hard coral cover is extremely low, where algae and coralline algae is more common. The bottom is covered mostly by coral rubble with occasional sand patches. Unlike a normal shallow reef with high relief (ledges, crevices, structure), PR is more appropriately termed “Pulley Plain” by the tech divers. The depth is generally constant within a foot over the course of a dive. Most of the sampling sites are between 190 and 230 feet deep, through murky thermoclines and often-ripping currents. Due to the low light conditions, the few coral colonies are spread flat to capture as much light as possible. As a result, most of their skeletons are extremely thin and brittle, making sampling with human hands the most feasible option. Additonally, some colonies of Agaricia have been fluorescently colored, perhaps indicating symbiotic cyanobacteria with accessory photosynthetic pigments to capture even more light. Comments are closed.
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