08/06/09 – First Dive
With all that has happened today, it is difficult to believe we have only been away from the dock for 12 hours!
To take advantage of the high tide, we pulled out of Harbor Branch Oceanographic Institution at 9 am and steamed our way to our first dive site. Along the way we had our safety briefing with the captain, all of us wearing “pfds” (personal floatation devices) during the talk. During the briefing, Dr. Sandra Brooke demonstrated how to don an immersion suit.
Before reaching the dive site, we prepared the gear needed for the first submersible dive of this mission. Almost every dive scheduled during the next week and a half will require that different sampling gear be loaded onto the submersible before it launches. The different gear is necessary because each scientist has his or her own particular research interest that requires a specific sampling device such as a sediment core tube or a filtered bucket.
The target location for the first dive was chosen based on previous work by Dr. John Reed. The sub was launched at 3 pm with Dr. Steve Ross in the front and Dr. Sandra Brooke in the back. When he returned to the surface, Dr. Ross summarized his experience:
"Most of the deep-sea bottom (beyond 200 m or 600 ft) is composed of soft sediments, mixtures of sand and mud. Our dive today, the first of this cruise, was on one of the most unusual habitats in the deep sea — a living, growing ancient coral reef. It’s an incredible experience to be in a manned submersible at 1400 ft (not really very deep by deep-sea standards) where the water temperature is 7° C (45° F). Let me describe the dive:
Sandra Brooke and I cruise along the typical bottom of sand riddled with burrows and depressions, then suddenly the bottom goes straight up and the sides of this mound are covered in coral bushes. As we climb the mound the scenery becomes more rugged and diverse. There are large bushes of the coral Lophelia pertusa (the major habitat forming coral in cold waters); there are dead corals that have become habitat for other animals; strange glass sponges in a variety of colors and shapes dot the seascape. Along with the many species of corals, we see anemones all waving their arms in the current trying to feed in these productive waters. Red squat lobsters climb high in the coral bushes and stretch long arms into the water to grab whatever swims by. On this dive we see more sharks, at least 4 species, than I have seen in most other places, and one of the scientists on board tells me that this may be a spawning area for these sharks. Other fish we see include Black Belly Rosefish, Conger Eels, marlinspikes, roughies, and alphonsinos. We make many collections, being careful to take only the samples we need for genetics studies, taxonomy studies, coral biology, fish biology, microbiology, and others. We end our dive near the top of the mound and having climbed over 100 ft from where we started.
We covered a lot of territory and our video transects will be used to classify the bottom habitats and examine the animals relationships to these habitats. We saw commercially important species like Golden Crabs on this dive. We saw few signs of human impact, which is becoming more and more rare. We leave the bottom after about three hours of work and feel that we made a good start. We feel good that this incredible collection of diverse animals appears to be thriving and healthy. We’ll see what tomorrow brings."
08/06/09 - No Data
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