by Dr. Sandra Brooke, FSUCML faculty

On Wednesday 4th May, I drove across Florida to West Palm Beach to meet the Waitt Foundation vessel, the M/V Plan B. It started out as a lovely sunny day but quickly deteriorated into a torrential downpour that lasted the rest of the trip. I arrived in West Palm, just in time to load my gear and hop on the boat before it left for Pulley Ridge, a unique mesophotic coral reef in the eastern Gulf of Mexico. Mesophotic or ‘twilight zone’ reefs are on the edge of the depth limits for reef-building corals that need sunlight to support their symbiotic algae. Their depth and distance from shore lends them some protection from high temperatures and human impacts, so they may represent refuges for corals and other reef species that can no longer survive in the degraded shallow areas.

Deploying the Falcon ROV at Pulley Ridge mesophotic reef

Deploying the Falcon ROV at Pulley Ridge mesophotic reef

This cruise is part of a larger project that is supported by the Waitt Foundation in collaboration with National Geographic and the Marine Conservation Institute. Brian Skerry, a National Geographic photographer, is aboard to collect images that highlight special marine ecosystems. My colleague John Reed (Harbor Branch Oceanographic Inst/FAU) and I are collecting benthic habitat and community data on the Pulley Ridge reefs. It was a rough trip down with strong winds and high seas, but we arrived at Pulley Ridge late Thursday night ready to start work.

We finally caught a break in the weather and deployed the Falcon ROV (See image above) on the main ridge inside the Pulley Ridge Habitat Area of Particular Concern (HAPC). Conditions were not ideal; we were being pushed around by the current and wind, but we saw some large red grouper excavations, each with attendant lionfish (unfortunately), fan-shaped green algae that only grows on Pulley Ridge, and large flat plates of coral that are characteristic of these mesophotic reefs. Growing as a plate instead of a boulder allows the corals to take advantage of the limited light (See image below). Towards the end of the dive we were venturing into territory that had not been explored before, and found a massive basin (probably a red grouper excavation) with hundreds of tiny fishes as well as large red grouper, scamp and black grouper. At this point the current pulled us off the reef and signaled the end of the dive.

Large flat plates of Agaricia coral at Pulley Ridge. Image courtesy NOAA-OER

Large flat plates of Agaricia coral at Pulley Ridge. Image courtesy NOAA-OER

Saturday and Sunday were again battles with nature with high seas and strong currents, but we managed two ROV dives on the western ridge before having to give up for the day. This part of Pulley Ridge is inside the HAPC but is outside of the small part of the total area that has any protection. This area is deeper than the main ridge and has a dense covering of gorgonians, sponges and many other invertebrates and fishes. An expansion of protection for Pulley Ridge has been proposed to the Gulf of Mexico Fisheries Management Council as part of a larger effort to protect deep sea corals (those > 50 m depth) in the Gulf of Mexico. Any additional data we can collect on the proposed protected areas may help move them forward.