A Better Understanding of Coral Reef Ecosystems

Pelagic predators such as these barracuda, Sphyraena qenie, are part of the coral reef ecosystem in the U.S. Line Islands (NOAA Photo by Kevin Lino).
A team of scientists have embarked from Hawai'i on a three-month survey of coral reef ecosystems at Johnston Atoll, the U.S. Phoenix Islands, the islands of American Samoa, and the U.S. Line Islands in the tropical Pacific Ocean. The overarching objective is to better understand the coral reef ecosystems of these areas, many of which are seldom explored. The research expedition is part of a regular monitoring program, conducted by the Coral Reef Ecosystem Division (CRED), headquartered in Honolulu, Hawai'i. The expedition is supported by NOAA's Coral Reef Conservation Program and involves extensive cooperation among NOAA scientists and research partners, including the University of Hawaii Joint Institute for Marine and Atmospheric Research (JIMAR), the U.S. Fish and Wildlife Service, San Diego State University, and the Papahānaumaokuākea Marine National Monument.

The research expedition will be carried out from February 27 to May 24, 2012 aboard the NOAA ship Hi'ialakai. Under the leadership of Chief Scientists Dr. Jill Zamzow, Dr. Bernardo Vargas-Angél, and Jamison Gove, a diverse team of researchers will be conducting multidisciplinary coral reef ecosystem surveys, assessing the status of fishes, corals, algae, marine invertebrates, and the oceanographic conditions in which these organisms exist. The scientific data collected during the three-month research expedition will enable informed and effective implementation of ecosystem-based management and conservation strategies for coral reef ecosystems, helping to ensure their protection for generations to come.

Thursday, November 4, 2010

You just can’t win them all.

by Oliver Vetter

I like oceanography. I’ve been studying it and doing field work my entire adult life, it has offered me amazing experiences as well as a rewarding, challenging and exciting career but there are a few things I’ve learned along the way... like it or not oceanography, and particularly the study and practice of field oceanography, is wrought with failure, occasional danger, frustration and mistakes. There is the old oceanography tale on an ocean wide cruise of the Professor leaving his graduate student in charge of a mapping instrument while he went for dinner, in days before high-frequency, high powered, computer aided instruments. The student was instructed to sit and watch the instrument and GPS. The instructions were simple; click the ‘on’ button once for every minute passed. An hour later the professor returns to find the instrument off and the student is sitting with his feet up. The professor asks, rather angrily why the student wasn’t concentrating on the GPS. “It ran out of memory after 45 minutes” the student replied. The professor, in rising horror and disbelief, repeats his instructions with the vital amendment: “click the ‘on’ button once for every minute Longitude passed…”

But a large part of oceanographic mishaps have to do with the inherent nature of the medium in which we, as oceanographers, spend much of our time: The ebullient, treacherous, unpredictable and seemingly endlessly challenging ocean. The first hurdle is that the moment perfectly well-made tools, knives, shackles, dive gear, boots, clothing, your own skin, anything electrical or any other article you might take for granted hits salt water, the timer starts: If you don’t have it washed packed and rinsed in ‘x’ number of minutes or hours, it will fail, break, tear, short or simply drop off and sink. Nothing is sacred and nothing is spared from the inevitability of corrosion. The second issue is weather and subsequent ocean state. What might be a simple operation at 8 AM, becomes a high-current torrent of white water with fire-hose like wind-spray by mid afternoon, making positioning, boat handling and even moving around the deck of a 18 ft boat likened to a sickness inducing dance on the back of a bucking horse. Just finding the correct position to drop divers becomes a juggling game of how far upstream to drop so they hit the mark, how much time to give them on the surface etc. To shed some light on these observations I will give an example from this very cruise. The oceanography team on the Hi’ialakai cruise HA1008 was requested by some colleagues to help them out by collecting some of their moorings from around Kauai. Each mooring was in approximately 100 ft depth and simply required a diver to find the mooring and remove the instrument from the mooring line with a large pair of bolt cutters. Simple enough.

Day one of this particular operation we had everything we needed; a GPS position, a basic understanding of what was happening, 28% oxygen NITROX gas for the deep dive and the 4 ft bolt cutters in hand. The wind was blowing about 25-30 knots by this point, so we knew there’d be some current at the surface so dropped a little upstream to try and hit the point correctly. We roll off the small boat Rubber Duck and quickly headed downward to get off the surface and out of the chop. At around 60 feet we could start to see the bottom and the current was lessening with distance from the surface wind. All was just fine but one small thing: there was no mooring. We started a search pattern, found some hard substrate, and dropped to 110 feet. We continued the search… and found nothing. I’ve no doubt the mooring was there, somewhere, but at 110 feet you’re limited on bottom time, we had about 10 minutes total, limited by nitrogen toxicity and volume of air. We return to the small boat empty handed.

There was no time for a repeat, these dives were one shot deals; particularly since we had special gas mixtures there was no time to return to the same place on a different day.

Day two and another mooring attempt, this time on the north side of Kauai and the weather was better. I was driving the boat and dropped the team on the site and watched them disappear beneath the waves. Expecting at any moment to see the mooring come to the surface I waited… and waited. The divers returned. This time they found the mooring; a success! However, the instrument that was supposed to be attached was gone with only a loop in the line to show it had ever been there. Failure again.

Empty mooring line at 79 feet.
Day three and one more mooring; this time on the east side of Kauai. Again, we dropped with our bolt cutters and spare air sources aiding our descent. Quickly we found the upper buoy of the mooring and hoping for better luck. Dropping to the bottom, at 120 ft, we find the instrument, real success!? I raise the bolt cutters to remove the instrument and triumphantly return to the surface… but it was not to be so simple. The bolt cutters were either old or poorly set, the cutting blades didn’t close all the way so wouldn’t cut the wire rope regardless of how hard I tried. Time was running low. We removed the instrument but had to leave the mooring to become part of the reef; it was already heavily grown over. We retrieved the instrument, but this was one small triumph in a succession of time consuming failures, on one of the most basic of operations.

On a typical year the oceanography team retrieves and replaces hundreds of scientific instruments of one type or other, through precise metadata (GPS points, descriptions) and well-executed and practiced operations, but for some reason, this particular series of events just didn’t work in our favor. And, after the ranting and raving and calculation of losses, you just have to learn, smile, and give the ocean a little more respect.

Bolt Cutters and spare air.......ready for the dive

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