Page 1

Enter the twilight zone of the ‘deep reefs’


Text: Laureen Schenk – Pictures: Barry Brown On the small Caribbean island of Curaçao, just off the coast of Venezuela, anyone can now discover the sea at a depth of 1,000 feet (320meters). All it takes to enter the twilight zone of the ‘deep reefs’, is to step on board the 5-person submarine called the Curasub. A miniature sub that cost a staggering 2,2 million dollars to acquire and that’s equipped with the latest technology and certified by Germanischer Lloyd’s. The mini-sub which not only meets but exceeds the highest safety standards takes its passengers to unreachable depths for divers and to places very few people have ever been. The Curasub is a mini-submarine that was designed and built by Nuytco Research Ltd. of Canada and that has been in operation on the island since January 1st 2011. Since that time the sub, which is being run by Substation Curacao, situated at Bapor Kibra Seaquarium on Curaçao, has already made over 700 dives. The sub was brought to the island by Adriaan “Dutch” Schrier, the man who in the eighties started construction of the Sea Aquarium and over a period of a quarter of a century made it into a beautiful oceanfront complex where dolphin shows, encounters with animals like sea lions, turtles, stingrays and sharks, dolphin therapy for handicapped children and submarine dives are all part of the daily routine. Including the pilot, the Curasub can carry up to five people. Although the Curasub is officially rated for a working depth of 1,000 feet, it has been physically pressure-tested to a significantly greater depth with a design factor of more than two thousand feet of pressure, making the Curasub a one-of-a-kind deepdiving tourist and research submarine. The hull of the sub is cylindrical in shape. It was manufactured of A516 grade 70 steel and is 47 inches (1.17 m) in diameter and 107 inches (2.67 m) long. Its power source consists of two pressure-resistant cylinders containing 20 lead-acid batteries each and able to provide nominal voltage of 240V. Maneuvering is controlled with 6 thrusters of 2 horse power each, with lateral control being exercised via the bow- and the stern thruster. Buoyancy is provided by 2 saddle- tanks, providing 1325 lbs of buoyant lift. The battery duration is almost eight hours, well in excess of the typical dive time of approximately one hour and a half and the sub has “Life Support” for 480 man hours, meaning that in case of emergency and with for instance 4 people on board, the sub can stay down for 5 days. From inside the Curasub passengers have a clear view with visibility of over 60 feet (30m). The two passengers sitting up front can look outside through a big acrylic viewport with 100 cm or 40 inch dimensions located on the forward end of pressure hull, while the passengers sitting in the rear have their own 14 inch ports to look through, while there are also viewports in the conning tower. In short, the viewports and the crystal clear waters surrounding the island of Curacao, give all those inside the submarine a perfect view of the colorful fish, corals and old shipwrecks a dive with the Curasub offers. The sub is furthermore equipped with a scanning sonar, two manipulating arms and a custom made sampling basket, making it a perfect vehicle for scientific marine research, observation, fish collecting and the collection of all kinds of other marine specimen.

Because of its technical amenities the mini-sub has in the last two years attracted the attention of renowned scientific institutes, universities, oceanographic research institutes and several distinguished scientists. Even the pharmaceutical industry is slowly getting interested in the operation that Substation Curacao is running. The marine organisms the Curasub is bringing up from the under-explored deep reefs are definitely organisms that the pharmaceutical industry would like to investigate so as to be able to determine whether they could be instrumental in the production of cures for certain diseases. Currently there are several researchers regularly coming to Curacao to dive in the sub. Dr. Carole Baldwin from the National Museum of Natural History of the Smithsonian Institution in Washington is one of them. She is one of just a few scientists exploring the so-called mesophotic, or “middle light,” reefs and involved in what the Smithsonian biologists call the Deep Reef Observation Project (DROP) in which marine life is collected and studied. Dr. Baldwin uses modern molecular tools like DNA barcoding. The DNA results on fish she and DNA specialist Dr. Lee Weight collected in the sub, led them to discover at least six new species of shallow-water Caribbean reef fishes. They are convinced that there are many more unknown new species to be found in both the shallow waters of the Caribbean, as well as in the deep reef. Among the about half dozen of Dr. Baldwin’s colleagues who as of 2011 regularly starting coming to Curacao to do collecting dives with the Curasub, is Dr. Jerry Harasewych. This shell expert is Curator in the Department of Invertebrate Zoology at the National Museum of Natural History and wrote several books and numerous scientific papers on the origin, evolution, and biogeography of deep-sea mollusks. Going several hundreds of feet down in the sub he’s been especially interested in finding slit shells (Pleurotomariidae). These shells appeared in the Paleozoic Era some 500 million years ago and have changed very little in all that time. Small wonder that they are also known as living-fossils. The reason for this interest in the slit shells that can only be found well beyond recreational dive depth is in fact understandable. When disturbed, the slit snail discharges a white milky solution into the water. An interesting fact is that this solution does not immediately diffuse into the water, but rather seems to hold together like a floating ribbon. Scientists believe that the snail discharges this secretion to deter predators and that the milky substance actually is some sort of ‘neurotoxin’ that affects the predator’s nervous system. That’s why Dr. Harasewych ‘milks’ the snails and collects the milky excretion for further research, as the solution might very well end up as useful to the pharmaceutical industry. Another institute Substation Curacao in the future hopes to be collaborating with, is The Royal Netherlands Institute for Sea Research (NIOZ), which is the leading research institute in the Netherlands for the marine sciences and is associated with the Netherlands Organisation for Scientific Research (NWO). Senior scientist in Marine Ecology in the department of Biological Oceanography at NIOZ Dr. Fleur van Duyl obtained her PhD degree in 1985 with the thesis: Atlas of the living reefs of Curacao and Bonaire, Netherlands Antilles. She is no stranger to the Curasub and was very excited about the possibilities the mini-sub offers when inspecting coral reefs. Dr. Van Duyl is expected to repeat the research she did a

quarter of a century ago for her thesis and may very well consider using the mini-sub when determining the actual state of the coral reef around the islands of the former Netherlands Antilles. For a regular trip in the mini-sub passengers pay $ 650.—per person. A price tag that each and everyone who booked a dive, afterwards considers worth every penny. Reviews about a dive in the sub and about its crew without exception range from “a spectacular dive” to “an adventure of a lifetime” and “worth making the trip to Curacao just for this opportunity”. Substation offers different kinds of dives with the Curasub. There is the “beauty run” that takes passengers to deep reefs with fantastic aquatic scenery and a huge anchor completely covered with colorful corals. Then there is the “ship wreck tour” to the 250 feet long Stella Mares lying on her starboard side in 450 feet deep water. Or one can book the “deep dive” going all the way to a thousand feet. And finally there is the “night dive” which can however only be booked by people who have done a daytime dive first. Before going on the dive the passengers get a complete briefing about the technical aspects of the submarine and about all the safety procedures that are in place. Because it is very obvious that the pilots and crew of Substation take safety very serious, the half hour briefing most always alleviates any worries passengers might have. The same applies for worries about being able to board an airplane and flying after a dive in the submarine. As the ambient pressure in the sub is the same as at the surface, there is no question of building up nitrogen in the body as happens when scuba diving. So there is no need either for one’s body having to off gas and no risk of getting decompression illness. After a submersible dive passengers can fly right away. At the briefing the passengers also meet the captain of the safety boat that accompanies the Curasub topside on every dive and who is in constant contact with the sub-pilot. Going down, the mini-sub is for the first 80 feet joined by an underwater photographer who takes the passenger’s pictures from outside the sub. Together with the pictures that are taken during the briefing, while getting on board the sub and from inside the sub by the pilot, these pictures are put on a USB-stick. The Substation T-shirt and the USB stick the passengers get to take with them will be the perfect reminder of an unforgettable experience.

RV Chapman will broaden the sub’s horizon In the near future the Curasub will be able to broaden its horizon, when the refurbishing of a research vessel that was bought to serve as a sub tender will be completed. Substation Curacao N.V purchased the Chapman, an old NOAA ship (National Oceanic and Atmospheric Administration) and intends to use the ship for carrying the sub to other locations. The Chapman will have accommodations for at least 10 passengers in five cabins, each with its own private bathroom. The Chapman was built and designed by Bender Shipbuilding and launched in December 1979. Length (LOA): 127 ft. (38.7 m), Breadth (moulded): 29.6 ft. (9.0 m), Draft, Maximum: 14.0 ft. (4.3 m), Hull: Welded Steel, Displacement: 520 tons, Gross Tonnage: 427 tons, Net Tonnage: 290 tons. By the beginning of 2013 the vessel should be totally refurbished and will start operating with the Curasub in tourism and science. This ship will give Substation almost limitless possibilities for submarine diving, initially mainly focused on the Caribbean.

Article in a Polish magazine; Nurkowanie