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OCULINA EXPEDITION 2005 Characterizing a Deep Coral Ecosystem and Assessing the Effectiveness of the Oculina Experimental Closed Area MISSION DISPATCH 5 October 16, 2005 OHAPC - Gulf Stream, off the east coast Florida Student Questions Answered As a follow-up to the September 17, 2005 teacher workshop, Treasures of the Deep - Deep Water Corals of the South Atlantic and the Oculina Bank (A Local Resource Workshop for Teachers), we invited teachers to have their students submit questions for scientists to answer while at sea on the 2005 Oculina Bank Expedition. Questions 1-5 are from Mr. Regan's Stone Middle School class and questions 6-12 are from Ms. Mazako's Fort Pierce Central High School class. Scientists aboard the Liberty Star have answered the questions. 
Question 1: How much of the 90 mile reef area is undamaged? (Zak, Stone Middle School) Answer 1: Good question, we really do not know and collecting more information to answer this question is one of the objectives of this expedition. As of last year, ROVs and submersibles surveyed less than 0.2% of the entire OHAPC. By compiling information from past dives, the current expedition, and future proposed dives we are trying to quantify how much of the OHAPC is damaged vs. undamaged. (John Reed, HBOI) Question 2: How long will it take to map the Oculina reefs? (Jake, Stone Middle School) Answer 2: Approximately one month of survey time is needed to develop a baseline map. This includes 30-days at sea for acoustic mapping and ROV dives to ground-truth. In addition, it will take approximately 7-8 months post-expedition to create the maps. It is important to note that in order to effectively manage the OHAPC (e.g., evaluate habitat changes over time and protection performance measures), the maps will have to be re-created every 3-4 years. (Andy Shepard, NOAA NURC). Question 3: Do zooxanthellae (symbiotic algae) live in deep water coral? (Rebecca, Stone Middle School) Answer 3: No, there is not enough light along the seabed of the Oculina Bank for zooxanthellae to survive. The symbiotic algae that occurs in shallow water reef corals is typically found in depths less than 200 ft. In waters greater than 200 ft, there is not enough light for the algae to live. Deep water corals can live in depths of up to 20,000 ft! Therefore deep water corals rely on a different feeding strategy. Deep water corals capture zooplankton or feed on particulate organic matter floating in water column. (John Reed, HBOI) Question 4: Why are you acquiring sounds from the reef? (Zak, Stone Middle School) Answer 4: One of the cruise objectives is to document fish presence and activity (spawning) on the Oculina reefs. Because the conditions at the deep water Oculina reefs are generally unfavorable for diving (i.e., depth, strong and variable currents) it is difficult to use diver surveys as the primary method to study fish. The use of hydrophones enables scientists to record sounds from the reefs. In general, the male fish are the primary sound producers and each species has a distinctive sound and acoustic signal. In addition to acoustic sampling conducted during this mission, scientists will deploy a long-term acoustic observatory on Jeff's Reef and deploy a video camera and sonar on Jeff's Reef on separate related missions to the OHAPC. As a result, a new observatory approach will be developed to provide documentation of these populations and their reproductive activities year-round. For more information, see DISPATCH 3. (Stacey Harter, NOAA Fisheries) Question 5: What causes ivory tree coral to grow in this exact spot? (Mason, Stone Middle School) Answer 5: The combination of hardbottom features and Gulf Stream currents make this area unique and able to support deep water O. varicosa. Cape Canaveral is one of two biological productivity hot spots (the other being Cape Hatteras) along the east coast of the U.S. Bottom geography and currents associated with the Gulf Stream, including upwelling and spin off eddies, make this area unique. (Andy Shepard, NOAA NURC) Question 6: What are the sediments like at different depths? Can you take samples? (Fort Pierce Central High School) 
Answer 6: In general the areas adjacent to the reefs are composed of coarser
sediments and finer sediments are found in areas between coral mounds. The
sediments in proximity to the Oculina reefs are primarily composed of shell,
ground up coral, and limestone outcrops. The areas between coral mounds are
primarily composed of oolitic ooze (shells and tests from diatoms) and
particles that rain out of the water column, including silt and sediments.
Yes, samples can be taken and we have collected approximately 20 sediment
grabs from various locations on this expedition for Kathy Scanlon, a marine
geologist at the United States Geological Survey, to analyze. (Amanda
Maness, UNCW, see photo 2)
Question 7: Is there a way to measure salinity and/or light at different depths? (Fort Pierce Central High School) Answer 7: Yes, different types of equipment can be attached to the ROV to record salinity and light at different depths. These instruments are generally called CTDs (Conductivity-Temperature-Depth). However, we have not been collecting this information on this expedition. We have been collecting depth, location, time, temperature, and other data using a few different devices including a CTD Thermister, which we have programmed to record temperature and depth every 15 seconds. You can access the data tables attached to previous dispatches. (Stacey Harter, NMFS). Question 8: How does the coral differ as depth increases? (Fort Pierce Central High School) Answer 8: Different coral species grow at specific depths. Each species has a specific zone that is ideal for its growth. For example, shallow water elkhorn and staghorn corals typically grow in waters up to 60 ft; however, a giant star coral may grow at depths of 200 ft. Oculina coral grows as deep as 500 ft and Lophelia coral can grow at depths greater than 3000 ft! (John Reed, HBOI) Question 9: Does the mineral content in the water change as you get deeper? (Fort Pierce Central High School) Answer 9: Yes, the mineral content of shallow water is going to have higher concentrations of carbonate limestone from ground up pieces of ledge. In general, deeper waters have greater concentrations of calcium carbonate, which comes from diatom tests. (Andy Shepard, NOAA NURC) Question 10: How many types of groupers did you find on this expedition? (Fort Pierce Central High School) Answer 10: So far, we have logged only two members of the snapper-grouper complex over the past 4 days, including scamp groupers and black sea bass (the first sighting since 2000; see October 15, 2005 log for more information). The snapper-grouper complex is composed of 73 species from 10 families. Representative species observed on previous Oculina expeditions include gag grouper, speckled hind, and various species of snappers. However, we have logged additional species of economic, commercial, and recreational importance including spiny lobster, cobia, sharks, and jacks. Keep in mind that the ROV is one of many tools used to document fish and it is possible that the adult fish are swimming away from it. We will know if additional grouper species are represented on the Oculina Bank once Dr. Glimore analyzes the acoustical data and deploys the fixed observatory. (Jocelyn Karazsia, NOAA Fisheries) Question 11: Do you find a lot of living coral growing on dead coral? (Fort Pierce Central High School) Answer 11: Yes, and this applies to any reef - shallow or deep. The ancient reef, which consists of limestone made by coral, provides the substrate on which new corals grow. In the Florida Keys, a person driving to Key West down US1 is actually driving on the limestone remnants of an ancient reef that is 125,000 old! As reefs die, new corals grow on top of the old, dead coral. This is also true for the Oculina reefs. In fact, the Oculina mounds are probably several thousand years old, but corals growing on top of these mounds are probably less than 200 years old. 
Question 12: What is it like to be under water in a submersible? Do you get
claustrophobic? Does it get colder in the sub as depth increases? (Fort
Pierce Central High School)
Answer 12: Glen Taylor (NURC) compares being in a submersible to visiting a moon of Jupiter - that is how alien it is! According to Taylor, the view is awesome - absolutely amazing! In general, once you reach 600 ft below the surface, the ocean is completely void of sunlight. However, may creatures (squid and jellyfish) at those depths are bioluminescent. In addition, many deep water creatures are attracted to the lights of the submersible and will start swarming around them. In general, submersibles are composed of two compartments: (1) the forward sphere, where the pilot and scientist sit; and (2) the aft compartment where one other scientist may sit. Taylor noted that neither compartments triggered claustrophobia for him. Yes, it does get very cold in the submersible as you go deeper. Taylor noted that in the middle of the summer, you must wear jackets and long pants. Taylor visited a deep water ecosystem (over 2,275 ft depth!) in the Gulf of Mexico and the temperature dropped to 4 C. 
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