A tinselfish (Grammicolepis brachiusculus) turns to inspect the RCV-150 ROV at Northampton Seamounts. Click image for larger view.

The Exploration Begins

September 18, 2002

Rachel Shackelford, Data Manager
Hawaii Undersea Research Lab

Currently, we are passing over the Northampton Seamounts. We arrived around noon and immediately started mapping the seafloor below us. These seamounts are about 40 miles southwest of Laysan Island at 23.5° latitude.

As far as we know, no one has ever explored this area before. We have no idea what we will find, but we are excited to see what is below us. We will continue mapping for the rest of the day. Frank Parrish (fisheries biologist with the National Marine Fisheries Service) will choose the first ROV dive site based on our newly created map of the area. Frank's project involves documenting monk seal foraging areas. He believes that monk seals from Laysan Island may dive down to the Northampton Seamounts looking for food. We will use the ROV and the Pisces IV submersible to explore the area and to survey fish species and size.

First Dive

Sean Corson
Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve

The alarm goes off at 5:30 am on the day of my first submersible dive. I am excited and a little bit nervous. I have that peculiar sensation that all of the information I have been cramming into my head for the dive is spilling out of my ears, which, from past experiences, usually means I am ready to test what I have learned. I am working with a team of scientists from NOAA, the University of Hawaii, and the State of Hawaii's Division of Aquatic Resources, to determine the impact of bottomfishing in the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve.

Leaving my cabin, I walk aft to the hangar bay where the sub crew was preparing the Pisces IV submersible for another day of work. The sub is roughly 20x10x10 feet. It is white with a bright orange tower over the hatch on top. It has a rounded or bulbous back and a flat deck on top. The passengers sit in a sphere tucked under the deck at the bow of the submersible. Baskets and manipulator arms used for collecting species are attached to the front of the sphere. The sub sits on skids on a sleigh that is towed in and out of the ship's hangar by a heavy winch.

At 7:30 am, the sub crew moves the sub into position on the aft deck and signals for Bruce Mundy, a fisheries biologist from the National Marine Fisheries Service, and me, to join our pilot, Terry Kerby, who is already onboard. Bruce and I climb a ladder to the top of the sub and lower ourselves down the narrow tower to the cockpit below. The cockpit is a sphere with a 7-foot diameter. Bruce and I lie down on either side of Terry and look out our view ports. The submersible is facing away from the ship. So I can just make out a portion of the deck and the ocean splashing against the ship's transom.

After a final pre-launch check, Terry signals to the crew to lift us off the deck with the large A-frame winch, and boom us out over the sea. The sub swings gently as we move closer to the water; suddenly the view ports resemble front-loading washing machines as we bob at the surface. Final checks are completed and we begin our descent.

I roll over and look at my surroundings as the light slowly fades from a bright, sunny shade of blue to a deeper midnight color. The sphere in which we lay is shaped like an upside-down ice cream cone. It tapers at the sides as it rises to the hatch and towers above our heads. All around the sides are numerous switches, lights and levers. The submersible is a beautiful piece of equipment. Although it is complex, everything is laid out in a clean, efficient manner. All of the wires are tightly bundled, the working parts fit together perfectly, and the sense that everything is in just the right place is so pervasive that it makes me embarrassed to think of the tangled mess running from my computer to the power strip back home at my desk.

After a gentle bump at the bottom at about 350m, we fix our position, establish radio contact, and lift off with the thrusters. As the cloud of sand billows away, I look out my viewport and get the feeling that I am in a mobile aquarium. We run transects identifying and recording everything we see (e.g., fish, corals, substrate, invertebrates). I am amazed at the diversity of animals and habitats.

The sub flies along crossing over deep ledges, flat pavement, around caverns, and along steep walls. As we glide over and though these features, it feels like we are in a hot air balloon or a glider looking down at a shifting landscape. Traversing up the side and along the summit of a large outcropping, we plough though rivers of small red Luzonichthys (fish) and arrive at a black coral forest. Large schools of snapper circle the sub, and sharks occasionally streak by.

Setting down on the bottom to get our position and begin a bait station, we open bags of ground fish and record what comes in to feed. Five or six Hapu'u grouper fill our viewports trying to look in and figure us out. The bait stations attract phenomenal sites. Meter long, graceful Onaga are joined by aggressive Kahala; a large school of Butaguchi suck at the sand and cough it back out like vacuum cleaners. These fish all have separate personalities, and they interact with one another like characters in a silent movie.

We lift off again and cross a barren desert of sand. If you look hard enough, you can find animals living in these regions, but they appear few and far between. During the dive, we alternate between stretching out, snatching bites to eat, and counting fish. Once we have finished our transects, we have enough time to push over a shelf and drop back down into deeper water. Using the manipulator arms of the submersible, we collect a few specimens before returning to the surface.

The viewports return to their washing machine mode when the ship picks us up. It doesn't seem like we have spent eight hours underwater, and I am ready to go back as soon as I can.

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