Ann and Bill were really getting into scuba diving. It was everything they had imagined it would be, and more. They were diving at a local quarry, and conditions were good overall. When they reached the platform 60 feet down, Ann noticed Bill was having trouble with his weight belt and moved in to help him out. She didn’t expect it to be a problem. Fighting with the belt and his gear, Bill twisted to one side and knocked Ann’s regulator from her mouth. Things went downhill from there.

The health benefits of scuba diving and the transferable skills gained from this sport make it one of the best alternative medicine therapies around.

As part of my role as a Miss Scuba United Kingdom finalist, I recently took my first flipper steps into the underwater world at Deep Blue Scuba diving club, Edinburgh, Scotland where I successfully completed Discover Scuba.

During the dive, I was amazed at how therapeutic this underwater sport is and how being underwater enhances teamwork and communication skills.

The underwater environment is proven to provide food for the soul where the body and mind is submersed into a state of calmness and wellbeing. The ocean has long been portrayed as a healing force – the cure of saltwater for cuts and wounds as well as the hypnotic and dream like trance of the waves in feeling at peace with the world. It provides an opportunity to “wash away the pain” and “feel replenished”. This is part of what makes scuba diving effective as a rehabilitation aid in support programmes for people with mental and physical disabilities as promoted by the highly admirable work of the charity Deptherapy.

I have known since my first days as a diver that people under stress are fighting panic and tend to make wrong choices. In an emergency, divers need a limited number of survival responses. The main danger with Scuba is no air. We need to get gas quickly, either from a buddy or the surface. Simple.

Rebreathers though can be quite complex as the manufacturer attempts to make them ‘hands-off’ or ‘fool proof’. As divers, we are taught to develop muscle memory so when a problem occurs we choose the correct response. With some rebreathers we are offered too many choices – which one do we select when we are stressed? Have we practiced all the drills since completing our training. Remember that we are often in deco so can’t just free ascend to the surface.

Within the Tech Dive community there is a mantra that too many gadgets equals too many points of potential failure. This does not seem to apply to rebreathers. My first CCR gave me a huge number of options depending on the problem I was presented with. Each one of those options had to go into the memory bank, and individual muscle memories had to be developed. My chest seemed to be covered in hoses, counter-lungs and fittings of various descriptions. To make matters worse, I had to learn drills for all these mechanical and electronic gadgets.

We are told during CCR training that we have more time to sort out a CCR problem than we do a Scuba problem. Usually a catastrophic failure on Scuba results in a sudden massive loss of air. Being out of air is easily recognized as there are masses of noisy bubbles and we inhale water, or nothing at all. Some CCR failures are insidious and develop over time, while others lead to unconsciousness very quickly. So what can we do about it?

The logical thing would be to simplify the rebreather operation and reduce the points of potential failure. ‘Simple’ is less likely to go wrong, particularly if it allows us to bail out.

Sharks: A Key Part of Ocean Ecosystems

As one of the top predators of the oceans, sharks play an important role in the food web and help ensure balance in the ocean’s ecosystem. As demand and exploitation rates for some shark species and shark products (i.e., fins) have increased, concern has steadily grown regarding the status of many shark stocks and the insustainability in global fisheries. 

Relative to other marine fish, sharks are characterized by relatively slow growth, late sexual maturity, and a small number of young per brood. These biological factors leave many species of sharks vulnerable to overfishing. Fishermen catch sharks in directed fisheries and also as bycatch in other non-directed fisheries. Many shark species have been over-exploited because their fins are highly valued for shark fin soup. 

Globally there is a general lack of data reporting on the catch of sharks, particularly species-specific data. For these reasons, sharks present an array of issues and challenges for fisheries conservation and management both domestically and internationally. Despite the challenges, NOAA Fisheries is committed to achieving sustainable management of sharks. 

Since Pacific lionfish were first detected off the coast of Florida three decades ago, they have spread around the Caribbean, gobbling up everything that fits in their mouths and reproducing at a phenomenal rate. Scientists have shown that soon after they descend upon a reef, there is a sharp fall in the number of small fish, notably the herbivores on which coral depends for survival. “They’re eating their way through the reefs like a plague of locusts,” said Mark Hixon, a lionfish specialist at the University of Hawaii. It is by far the most destructive invasive species ever recorded at sea, and the blight is believed to have started with aquarium fish released off the Florida Atlantic coast in the mid-1980s.

We’ve all seen it in the movies. The main character splashes into the water, a cool looking mouthpiece gripped in their teeth, and they proceed to escape, do battle, or otherwise enjoy the benefits of a scuba system without the requisite scuba gear. To say that it’s a dream for divers to be less encumbered when underwater is an understatement. There is a whole minimalist sub-culture in recreational diving, dedicated to minimalizing the amount of gear they need to safely dive. So what’s brought all this on? The Triton Artificial Gill.

Rebreathers could make an ocean explorer’s ultimate fantasies come true. Recirculating the same air again and again might sound like science fiction, but compared against traditional scuba equipment, rebreathers allow divers to go deeper, stay under longer, and get closer to wildlife. It’s everything a diver would want. So why haven’t they outright replaced scuba gear in the underwater swimming industry?

The same factors that hold back every other emerging technology: they’re still too expensive and too unsteady.

This is in spite of the fact that the technology on which rebreathers are based actually dates back to the 19th century. Today, dozens of manufacturers offer different styles of rebreathers to suit divers’ needs, and the systems keep getting cheaper, safer, and more reliable. There’s no doubt rebreather diving’s popularity is trending upward.

Yet, it’s still a fringe element on the scuba scene. While popular for technical diving, underwater videography, and military applications, rebreathers are still not part of standard training for the vast majority of divers. What gives?

Belize's Lighthouse Reef contains something of an anomaly: After all, when we see sinkholes on the news, they're usually disastrous and frightening, swallowing up Australian campgrounds and Florida used car lots with abandon. But let's not forget the fun, chill kind of sinkhole: the underwater kind! The Great Blue Hole of Belize, for example, is not just the most obviously named place in the world (tied for #1 with Australia's Great Sandy Desert). It's also a bucket list destination for just about every scuba diver on the planet.

BAROS, MALDIVES

Underwater: Baros has its own house reef, close enough to the shore that snorkellers can swim to it. In addition, there are 30 dive sites within an hour of Baros, all with spectacular reefs and vibrant marine creatures. And the 'Diving by Design' programme ensures that each diving experience is tailored to the individual's needs.
Above water: Elegant villas sit on stilts in the water or along the island's white-sand beach. Both food and atmosphere are important here, with sunset trips on a traditional dhoni to a sandbank where guests can dine privately under the night sky.
Best time to go: Underwater visibility is not as clear in the summer months when masses of plankton float here, but this in turn attracts whale sharks and manta rays.
Baros: North Malé Atoll, Maldives (00 960 664 26 72; 

If you plunge into the sea to ogle exotic wildlife, why not stay a while—and get an even closer view? Cave-diving engineer Bill Stone [see "Journey from the Center of the Earth," February 2007] makes that possible with the most user-friendly version yet of a rebreather, a device that recycles your exhaled air, removes carbon dioxide, and adds oxygen. (A scuba device quickly burns through tanks of fresh air.)

On a typical dive, the Poseidon Discovery lets divers stay underwater at least three times as long as scuba gear can, and since you don't exhale into the water, you don't create bubbles or noise that can scare off fish.

Military and advanced divers have used rebreathers for decades, but they're pricey rigs (about $10,000) that require extensive training on how to manually mix gases in case the gear fails. Stone's recreational model automates the safety system with built-in computers that check all components pre-dive, plus two oxygen sensors that monitor the gas mix. If the system spots an air-recycling malfunction, the mouthpiece vibrates and blinks an alert. Just flip its lever to inhale from a small fresh-air tank and return safely to the surface.

Neoprene is a synthetic rubber that's often used to make wetsuits, hence its alternative name "scuba." It's also used in electrical insulation and drum practice pads, but don't let the industrial uses scare you off. Neoprene has become increasing popular as a material to wear on the street (not just in the sea) because many of the qualities that make it great for use in factories, like stain resistance and general durability, make it great for clothing, too.

The fabric is thick and doesn't breathe, making neoprene a perfect addition to your winter wardrobe, and the thickness also allows for creation of structured pieces that look out of this world. The weight of neoprene also means form-fitting skirts and dresses are more forgiving. You'll never run the risk that your bodycon skirt or tight leggings are accidentally a little bit see-through. The material is always opaque, and its resiliency means it doesn't really stretch out. Neoprene also holds photorealistic patterns well, so it's not uncommon to see huge florals or intricate pattens splattered all over a dress or a sweatshirt. Did I also mention it's incredibly comfortable.

My Road to Instructor

My name is Javier Cantellops and I have loved the water since I was born. I have just recently become an Open Water SCUBA Instructor. I have also just landed an amazing job on the paradise island of Maui. This is the story of how I became an Open Water Instructor, the path I took to get to live my dreams, and my perspective on what it takes to do it. My journey was not your average one, that is for sure, but the outcome was nevertheless standard. Meaning if you want it, it can be yours.

I started my diving career as a free diver, free diving wherever I've lived.

I've explored the reefs of the Big Island, been spearfishing in Costa Rica and had always gone scuba diving with my friends along the way just for fun.  I'd never had any classes, just always knew what to do and most importantly what not to do (i.e. don't hold your breath on scuba). That was pretty much all I knew.

After a wild and successful business venture in Costa Rica, and becoming absolutely hooked on diving, I decided, after long thought, that diving was what I wanted to do so we sold the business. I was 32 years old at the time and my son was three and I decided to make a change. So we moved back to the states and staged out of South Carolina, my "hometown", trying to figure out exactly what it was that I was going to do. I had just the barest ideas of what I wanted life to be about. I wanted to be in the water, I wanted to share my passion, I wanted to help people find excitement, I wanted to be an instructor...

I recently left my job as a deep sea diver. I worked for a large company that offers diving services ranging from salvage, underwater demolition, ship repairs, and search and recovery. They are a reputable company and are considered safe and reliable. So much so that they are often contracted by the government. Truth be told, I will miss working for them. The people I worked with were truly the best of the best. But there are only so many unexplainable things you can witness in the deep before you decide to stay out of the ocean forever. Here are some examples of the secrets many divers take to their graves.

The Newtown Creek, a 324 foot tanker vessel, has arrived in South Florida and will soon be sunk in late July as an artificial reef 1 ½ miles off Pompano Beach’s shore. This ship will be one of the biggest contributions to Florida's artificial reef system and one of the most easily accessible major dive sites in the nation. The ship will be the centerpiece of what will become known as Shipwreck Park, surrounded by 16 other existing wrecks covered with marine life. Shipwreck Park will be a unique underwater cultural arts park with rotating underwater art exhibits. The ship will include specific themes, exciting underwater events, artwork and rotating art exhibits to create a unique dive experience for local and international tourists.

This tanker ship which is longer than a football field was sold by the City of New York to The Shipwreck Park, Inc., a private 501 (C)(3) corporation, at a greatly reduced price. Shipwreck Park, Inc. has received sponsorship from the City of Pompano Beach and the Isle Casino Racing Pompano Park for the purchase, towing, cleanup, installation of artworks, and sinking of the ship. The ship was towed from New York to a facility on the Miami River for cleanup and installation of artwork before the sinking.

Pompano Beach artist Dennis MacDonald was hired to create several fun and unique underwater displays, including a casino theme for the ship deck. The art displays will include a swim-through cascade of gigantic dice, great for photo opportunities, as part of the Isle Casino Racing Pompano Park sponsorship. 

The new Ventura is an extremely versatile BCD. This lightweight back inflation BC which weighs less than 5 lbs is fantastic for travel. But it is also a great BCD for local diving as well. Whether diving in Cozumel or Catalina the Ventura is designed from the ground up to be the best BC in class.

At only 4.7 pounds, it’s much more than the typical lightweight BC. The Ventura aircell is made of Double Coated TPU, which basically means it doesn't absorb any water and it doesn't gain water weight after repeated dives, a real plus when traveling. This Double Coated TPU material is extremely durable, and as a result we are able to increase the warranty on the bladder from Two years to Five years.

The Ventura is rugged, extremely compact, exceptionally stable, and features our uniquely designed integrated weight release system.

The QDS Weight System is a very simple yet effective weight system that allows 16 pounds of ditchable weight.
More features. Less weight. Perfect for travel.

My first dive was in a murky lagoon in Key Largo, Florida. I bumbled along with a herd of excited new divers, stirring up the soft, oozing muck at the bottom of the lagoon. Diving was fantastic, but I didn't see much. For most of the dive, I was enveloped the brown cloud of bottom sediment that the divers had stirred up. Our finning technique, the flutter kick, was quickly reducing the visibility in the lagoon.

The flutter kick is an inefficient kick. It propels water above and below the diver, which does not contribute to forward motion and wastes energy. The downwards propulsion of water also disturbs sand and other bottom sediment, leading to a reduction in visibility. The frog kick is a much more effective kick, and is easy to learn with proper instruction. Click through this tutorial to learn the basics of the frog kick.

Our sea creatures are in trouble. What with warming temperatures, pollution, plastic debris and over-fishing, the oceans need protecting more than ever before. And governments are becoming more committed to creating marine reserves. But are they just paying lip service to the problem or really addressing it? Too often a marine reserve allows commercial fishing and other exploitation. A marine reserve which isn’t really a marine reserve at all.

The new IUCN Red List reveals that growing human pressures on whale sharks and slender hammerhead sharks are putting these species at an increasing risk of extinction. Both the shark species are now listed as Endangered.

Numbers of whale sharks (Rhincodon typus), the world’s largest fish, have more than halved over the last 75 years as these slow-moving sharks continue to be fished and killed by ship propellers.

Although conservation action in India, the Philippines and Taiwan has ended large-scale fishing of whale sharks in these countries, they continue to be fished in other locations, including southern China and Oman. As whale sharks and tuna are often found together, the sharks are frequently caught by tuna fishing boats.

Unregulated fishing is also behind the fast-falling numbers of the distinctive slender hammerhead shark (Eusphyra blochii), whose shape makes it easily get tangled up in fishing nets. This species has moved from Near Threatened to Endangered on the IUCN Red List.

Although it is difficult to say how many individuals remain, recent surveys of fish markets in Indonesia found only one slender hammerhead shark among approximately 20,000 sharks of other species. A similar pattern is expected throughout Asian countries where coastal fishing is intense and largely unregulated.

“It is alarming to see such emblematic species slide towards extinction,” says Jane Smart, Director of IUCN’s Global Species Programme. “These new IUCN Red List assessments emphasise how urgent it is for the conservation community to act strategically to protect our planet’s incredible diversity of life.”

A full update to the IUCN Red List of Threatened Species, including assessments of many other species, will be announced at the IUCN World Conservation Congress 2016 to be held in Hawaii from 1 to 10 September.

Whale sharks are found in all tropical and warm seas except the Mediterranean. The rise of dive tourism in many areas is making the fish more valuable alive than dead in some locations, including at Ningaloo Reef in Western Australia, Donsol in the Philippines, Placencia in Belize and Isla Contoy in Mexico. In all these places, and in other countries like the Maldives, India, Thailand and Malaysia, the whale shark is protected. However, the whale shark migrates long distances out of the safe areas and into the fishing zones.

It's a fact: we need oxygen to live. It's because of the way our cells use oxygen that we are able to breathe, exercise, and even think. In each of our cells, structures called mitochondria take the oxygen which diffuses in from our blood, disassemble it into its two component atoms (remember, oxygen - O2 - is composed of two oxygen atoms), and then hook some available hydrogen nuclei to them to form water.

The process releases energy, which is used for all functions of life. The problem is that in disassembling the oxygen molecule, it involves a step in which an extra electron is hooked on. This forms an intermediate called a superoxide anion, and this is a bad actor. It is highly reactive, and it will make mincemeat out of most other molecules it comes in contact with.

These anions are like coals in a furnace: as long as they are contained, we get lots of safe chemical energy; if they get out we get a great deal of damage. The mitochondria are designed to contain these superoxide anions, but just in case some get loose, there are a host of protective chemical reactions designed to sop them up and prevent them from doing any damage.

Besides producing excessive amounts of the superoxide anion, elevated tissue oxygen levels also affect a variety of other biochemical reactions which may affect oxygen toxicity in ways that are only beginning to be understood. Tissue-protective mechanisms and biochemical reactions are tuned to life in an atmosphere containing 21 percent oxygen, or 0.21 atmospheres absolute (ata) oxygen partial pressure. (See sidebar: "Remember Partial Pressure?", page 34.) As the partial pressure increases above this comfortable 0.21 ata, protective mechanisms are slowly overwhelmed and biochemical reactions are affected. This may eventually result in "oxtox," or oxygen toxicity.