Galápagos Islands: two perspectives; Koh Tao, Thailand; Ambon, Indonesia; Bikini Atoll wrecks; Double sinking in Portugal, a first; Stig Åvall Severinsen profile; Hypoxia research; Critters underwater, British Columbia; Dive fitness: Neptune's triceps; Switching to rebreathers; Tips on mirrorless cameras; Plus news and discoveries, equipment and training news, books and media, underwater photo and video equipment, turtle news, shark tales, whale tales and much more...
Main features in this issue include:
Many of the pieces of equipment used by technical divers look different to the equipment used by recreational divers. However, for most of the time, the basic principles are the same.
A rebreather is simply a way to reuse the gas breathed out by the diver in conjunction with a method of removing the carbon dioxide produced by the diver. The main advantage of a rebreather is that it is much more efficient on gas usage.
Unlike Max in the children’s book by Maurice Sendak, Where the Wild Things Are, I hadn’t worn my wolf suit, or made mischief of one kind or another. I hadn’t been sent to my room before it transformed into an island of magical monsters only reachable after a year of sailing.
I wouldn’t want to spend that long on a boat, so I behaved(ish) and looked forward to being on Galápagos and spending my nights tucked up on dry land.
My dive buddy Simon’s left arm shot out, index finger extended, and he clenched his right fist and stuck it on the side of his head. I quickly scanned left and right, peering through my mask into the milky blue water. “Where?! Where?!” my brain implored. “There!!!” my eyes answered.
Seen from space, Isabela Island—the largest island of the Galápagos archipelago— reminds me of a giant seahorse facing the great blue yonder of the Pacific Ocean. As one approaches land, the cap of thin white clouds dissipates. Isabela’s majestic landscape is a perfect alignment of shield volcanoes, rising above 1,000 metres, which stretches from the southeast to the northwest. Among them, Wolf Volcano reaches 1,700 metres.
Straddling the Equator, it is the highest summit of the Galápagos group. Over the last 700,000 years, the six volcanoes of Isabela Island—Cerro Azul, Sierra Negra, Alcedo, Darwin, Wolf and Ecuador—have evolved into gigantic calderas.
What is the hypoxia? It is a deficit of oxygen in the lungs, blood and tissues. Each of us feels hypoxia from time to time, even if we do not realize it.”
The dream of the “Blue Abyss” is embodied in the depth records of some of the most famous divers—Jacques Mayol, Francisco Ferreira and Umberto Pelizzari—who have destroyed so many myths and even scientific theories about the limited capacity of humans as overland beings.
Freediving is easy. All you have to do, according to freediver extraordinaire, Stig Åvall Severinsen, is “learn to hold your breath as long as you can”. Simple.
Well, in the words of the Bard, “There’s the rub”. Severinsen accomplished this by transforming a sport into a personal philosophy.
If anyone was to mention diving in Thailand to you, then you would most likely think of one of the west coast destinations. Hardly a thought would be given to the small island of Koh Tao, which lies off the east coast in the Gulf of Thailand. I live and dive here, so I find this lack of attention a little unfair.
Yet, it’s hardly surprising, as it’s largely overlooked by dive travel specialists, and for the most part, dismissed as nothing more than a diver training centre.
One of the dreams of any naturalist is to be the first to find and detail the life of a hidden or unknown animal first hand. Since 2003, scientific divers with the Greenland Shark and Elasmobranch Education and Research Group (GEERG) have begun to unravel the mysterious life of the Greenland shark, which at over seven meters in maximum body length and exceeding a ton in weight, is the second largest carnivorous shark after the great white.
Primarily a deepwater shark of the northern boreal oceans, Somniosus microcephalus is the only shark that patrols beneath the ice of the Arctic Circle. Hundreds of thousands of these sharks have been caught in directed fisheries, and yet little is known scientifically about the species.