My plans called for heading out from Port Aransas, Texas aboard MoAzul on Wednesday, August 29 about the time Hurricane Isaac is expected to slam into the northern Gulf Coast.
I hoped to watch Greg Stuntz, Jennifer Wetz and other scientists from the Harte Research Institute for Gulf of Mexico Studies conduct ROV surveys of two more sites, MU-A-85 and MU-A-16, which you can see from the map are far offshore, where waves were predicted to be as high as four feet or more. For those of you just joining us, the HRI crew is conducting a two-year study of fish and marine life around 15 of the 66 artificial reefs off the Texas coast. Funded by the Texas Parks & Wildlife Department, the study aims to settle an ongoing debate about whether these structures increase the productivity of the marine ecosystem, or simply serve as popular gathering points for fish and other critters. We already know artificial reefs are a key part of the multi-billion-dollar recreational fishing industry; we aren t sure whether they re also critical as spawning habitat and sources of food and shelter.
The answer could change current federal policies that call for removing thousands of offshore oil and gas platforms once they cease production, and perhaps fine-tune and bolster participation in artificial reef programs in Texas and Louisiana.
So far, the team has surveyed six of the 15 sites. As I reported previously, they ve been hampered by competition for the boats they use to get to the sites, and by fickle Gulf weather. While lab work can go on during just about anything short of a hurricane outside, field work proves a bit more challenging. This week s scrubbed mission is a case in point. The little 13-pound ROV needs surface waves of about two feet max, and currents below two knots to operate safely and effectively.
Operating an ROV resembles playing a video game, except that the controls move a physical rather than a virtual vehicle. Operating those controls isn t easy, even for graduate students raised on electronics. The operator s field of vision is limited to directly in front of the video cameras on the front and back of the ROV imagine driving down the highway with all your windows blacked out save a round hole right in front of you. The operator watches the vehicle s progress via images from those cameras projected on the computer screen. An umbilical cord of fiber optic cable inside what looks like a thin garden hose controls the cameras, lights, forward and rear thrusters, and the machine s descent and ascent.
The umbilical itself creates drag and can be whipped about by currents on the surface and at depth. On previous cruises, I ve seen currents suck both the umbilical and ROV into the maze of pipes beneath a rig. When that happens, it can be terribly easy to snare or damage the cord. Divers usually stand by to go in after the ROV, but they can t help below about 130 feet, nor would recovery be simple for them in rough conditions.
Onboard conditions are a factor as well. If you ve never been offshore on a small- to medium-sized boat, it s hard to imagine the funhouse atmosphere when wave heights reach about three or four feet. Suppose your office is balanced on a line down the middle, the sides rocking, one goes up by three or four feet, the other down, then they switch places. When you try to take a step, the floor moves before you complete it, and your foot doesn t come down on the spot you intended. Sober, serious scientists lurch around a ship lab like a bunch of drunks. Just because your work doesn t require you to move doesn t mean you re home free, either. Standing on a swaying ship staring at the stationary screen of a computer is almost a sure-fire recipe for developing seasickness, and drugs effective at treating it aren t exactly conducive to accomplishing good work.
Scientists refer to research outings at sea as cruises, which their colleagues and the general public may understandably assume resemble the pleasure kind. Admittedly, sometimes they do. In August 2010, on board a research ship in the Gulf, I experienced some of the most beautiful, calm blue water ever. You could have water skiied on the stuff. (See the dolphin photo, taken from the back of that boat.) But most of the time, research cruises aren t so lucky. Many of them intentionally go places known for bad weather.
So, no counting fish this week. We ll wait for Isaac to pass.
Previously in this series:
Counting Fish: Gulf of Mexico Artificial Reef Survey
Counting Fish: on the artificial reefs
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