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Drake Passage Opening

Aloha!

My students are studying all about the transfer of energy through our local marine ecosystems. In Hawaii, many of our corals have zooxanthellae helping them get food because our water is so lacking in nutrients. In looking at the corals being studied in the lab on your ship...

  1. Do they contain algae to help them get food?
  2. My students thought corals were mainly a tropical,a warm water marine life form. How do the corals your scientists are studying differ from the corals that live up here?

Thank you so much for all your hard work. I hope you and all the scientists can make it through the big storm. Rough seas can make it really hard to walk around and do research on a boat!

warmly,

Maggie Prevenas

Mon, 04/28/2008 - 08:32

Katie Pena

Aloha Ms. Prevenas!
Thanks so much for the excellent questions. I referred your questions to our resident expert on corals, Rhian Waller, an assistant researcher at the School of Ocean and Earth Science and Technology at the University of Hawaii at Manoa.Here is her response to your questions:
1. These corals don't have algae in them to photosynthesis, instead they survive on food fall from above (so dead plankton raining down, smaller animals dying and decomposing all reaches the seafloor eventually). There are two main 'types' of coral - zooxanthellate (which only live in the photic zone) and azooxanthellate (which can also live in the photic zone,but are mainly found in the deep ocean).
2. There are actually deep-water corals around Hawaii too and that's what I study back in my lab at UH. Deep water (also known as cold-water) corals occur all around the globe - from the Antarctic to the Arctic, from just a few meters in really cold water (like down here) to well over 6000m in the deepest ocean. Around Hawaii the shelf drops off from the islands veryrapidly to deep-water, and we have good strong circulation with productive upwelling, making an ideal environment for deep-water corals to grow. These deep-water corals can be remarkably similar to their shallow water counterparts, they can form large reefs and attract a wide array of associated fauna like fish, crabs, snails and starfish (among many others).The corals we find down here are remarkable to live in such cold water (it can be just 0.5C on the bottom here), and we don't really understand how they do that - understanding how they live, grow and thrive in these conditions is one of the major goals of my research.
Also, you and your class are welcome to contact me directly for more information if you would like.
**Rhian is so great and I am very thankful she took the time to answer yourquestions.
--Mrs. Pena