Climate change is predicted to cause a series of maladies for world oceans including heating up, acidification, and the loss of oxygen. A newly published study published online in the April 24 edition of the Proceedings of the National Academy of Sciences entitled, "Ocean warming since 1982 has expanded the niche of toxic algal blooms in the North Atlantic and North Pacific Oceans," demonstrates that one ocean consequence of climate change that has already occurred is the spread and intensification of toxic algae.
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Covering seventy-one percent of the Earth’s surface, the ocean provides us with a magnificent variety of creatures. Each of these creatures occupies a unique position on the food web, or trophic web, which is composed of producers, consumers, and decomposers. For an environment to remain healthy, the food chain must remain unbroken. If one link in the chain is broken, all creatures on the chain may be endangered.
On 7th February 2014 a two line report was posted on the forum 'Rebreather World', advising of a Norwegian diving incident.
"Sadly, two divers died in the caves of Plura yesterday. They ran into problems at ~130m. Three team mates made it back to the surface and [sic] was taken to the chamber. The three divers are OK.
The Dive Plan
In the world of caving and cave-diving, physically discovering the link between different cave systems is a significant exploration achievement. Once linked, if the system is very challenging, it is quite possible that very few cavers / cave-divers, if any, will subsequently make the known through-trip.
In early 2014 five friends decided that they wanted to dive the Plura Cave through-trip. The plan was that two teams of rebreather divers - a buddy pair and a team of three - would enter at Plura, dive the system, and exit at Steinuglefåget.
The team would then overnight in a rented house near the Plura entrance, then dive the system in reverse the next day. The planned dive time was five hours, with a maximum planned depth of 129 mt / 423 ft. The team would carry bail-out gas and bailout rebreathers.
On the 6th February 2014 the first team made a hole in the ice at the Plura 'start site', whilst the second team drove to the Steinuflåget 'end site' to leave clothing and equipment. The second team then returned to Plura, and helped the first team finish kitting up. Once the first team were in the water, the second team prepared for their dive. They entered the water about two hours after the first team.
Long story short, this story changed the lives of the five friends forever. One diver in the first team got stuck in a restriction in the cave at 110 mt / 360 ft and subsequently died.
The second team were unaware of the tragedy as they entered the water. Their first part of their dive was also uneventful, until the three divers came across the body of their friend. A second diver then died. The three surviving divers made it out of the system safely, but were all hospitalised with decompression sickness. They were subsequently interviewed by the Norwegian authorities, who promptly closed Plura cave.
Official Body Recovery
The Norwegian authorities planned an official recovery operation of the two bodies. They called in three renowned British cave explorers who specialise in rescue and recovery work in caves, to do the job. The team comprised of Rick Stanton, John Volanthen and Jason Mallinson.
The team accessed the cave from Steinuglefåget and surveyed the accident site.
""It was evident that it was going to be quite a protracted affair, lots of dives, down deep and cold - and that was really beyond our remit," stated Rick Stanton. "The only alternative was to perform the traverse from Plura all over again, and thus gain access to the victims from the other side."
The team deemed the process was too risky, and the Norwegian police called off the recovery. Plura Cave remained closed.
Over-fishing is driving sharks to the brink of extinction. In fact, many populations have seen a decline of up to 80%. Healthy oceans depend on healthy shark populations because they keep the marine food change in balance. Sharks grow slowly and produce few young – meaning they are incredibly vulnerable. The saddest part? Many of the leading factors in the decrease of populations of sharks are caused by human activity.
Here are seven types of sharks we think are work getting to know (and help ensure they have a brighter future).
The HMCS Saskatchewan is British Columbia's most successful artificial reef. The popularity of the Saskatchewan is apparent when you consider that well over 100,000 dives have been completed since she was sunk on June 14, 1997: more than all other B.C. artificial reefs put together!
Click On The Image To Watch A Video Of The Sinking!Hundreds of boats, including a ferry that B.C. Ferries and it's crew donated as a viewing platform, gathered just off the western side of Snake Island, a bird sanctuary and home to over 250 harbour seals, to watch the sinking. In just over 2 minutes the 366 foot Saskatchewan slipped below the surface and began its descent to the sandy bottom where it came to rest in 130 feet of water with a 6 degree list to the portside. The bow faces to the south and the stern to the north. The top of the mast is at 45 feet and the bulk of the vessel is between 80 and 100 feet.
B.C.'s Most Popular Reef!The approximate depth to some of the most popular and identifiable features are:
Radar Platform on main mast ..........45'
Bridge .......... 65'
Top of guns .......... 85'
Fore and aft decks ..........95'
Aft mortar bay .......... 105'
Keel at bottom .......... 130'
Look at all the diver access holes cut into the vessel. This creates lots of ambient light and a safe diving environment for you!
The community of Nanaimo has wholeheartedly embraced The Saskatchewan. Our community's dedication to diving is evident throughout NanaimoOne of Jeff King's Great Murals! . Downtown, next to the Courthouse, the Weyerhaeuser building boasts one of Jeff King's, Nanaimo's renowned marine muralists', best murals. This large mural and it's amazing detail covers the entire side of the building. Make viewing this mural a part of your visit to Nanaimo.
Make Diving The Saskatchewan part of your travel plans this year! Have a look at the great value we offer in our Diving and Snorkeling packages!
Want to learn a bit more of the history of The Saskatchewan, read T.W. Paterson's article on the Noble past of The HMCS Saskatchewan:
HMCS SASKATCHEWAN HAD A NOBLE PAST
Looking Back Article by T.W. Paterson, Harbour City Star, February 13, 2001
"The bottom of the sea is a funny place for a piece of Canadian prairies, but there you have it since the sinking of HMCS Saskatchewan as an artificial reef, in 1997.
Our second Mackenzie class destroyer escort, she was commissioned at Esquimalt's Yarrows Ltd., Feb. 16, 1963. At 366 feet long, with a 42-foot beam and a displacement of 2,900 tons (fully loaded) she had a top speed of 28 knots and a complement of 230 officers and men.
Built when Canada's destroyers were internationally renowned as 'Cadillacs', Saskatchewan honoured the river of that name, rather than the province, and was the second ship of this name to serve the Royal Canadian Navy.HMCS Saskatchewan Emblem
Her ship's badge shows a sheaf of wheat imposed on a green field, with a wavy white and rad diagonal strip denoting a river. All colours are derived from the province of Saskatchewan's coat of arms.
Her predecessor was commissioned in the Royal Navy in 1935 as HMS Fortune, of the Fearless destroyer class. During the first 3½ years of the Second World War, she steamed more than 2000,000 miles (that's eight times around the world), participated in the Norwegian campaign and the occupation of Iceland, and shared in the sinking of the U-27, U-24 and the Vichy French submarine, Ajax.
While serving out of Malta in May 1941, she was badly damaged by bombs that required six months to repair.
In 1943, after two years with the Eastern Fleet, Fortune was renamed Saskatchewan and transferred to the RCN at London. She joined Escort Group C-3 after refit, trials and workups, for convoy escort duty in the North Atlantic. Saskatchewan and her sisters escorted no fewer than 14 convoys in nine months until withdrawn in May, 1944 to begin special training off Londonderry, North Ireland in preparation for the invasion of Europe.
In June, she helped to patrol the English Channel "as part of a barrier" to prevent U-boats from attacking the invasion route to the Normandy beaches.
During an offensive patrol in the Bay of Biscay, the Canadian managed to destroy three enemy ships and complete further patrols in British waters before Saskatchewan was ordered back to Canada for refit in august, 1944. She spent the last five months of the war as an escort vessel, returned to Canada after V-E Day, and rounded out an outstanding career as a troop transport.
Paid off for disposal on Jan. 28, 1946, the weary destroyer was sold for scrap, leaving three hard-won battle honours: Atlantic - 1943-1944, Normandy - 1944, Biscay - 1944.
There's even more naval history behind Saskatchewan than this. The only naval engagement of the Riel Rebellion was fought on the South Saskatchewan River (Kisikatchewan - rapid river in Cree), in 1885. Government forces requisitioned the stern-wheel steamer Northcote, armed her with a Gatling gun and 50 soldiers, armour-plated here with planks and sandbags, and sent her against the rebels at Batoche.
But they riddled here in small arms crossfire and launched another riverboat into her path, damaging the Northcote and forcing her withdrawal.
In 1968, the latest HMCS Saskatchewan sustained extensive damage from striking a rock at the eastern entrance to Active Pass and again, two years later, off Roberts Bank. Both accidents resulted in courts martial and severe reprimands for her respective captains.
In 1997 HMCS Saskatchewan touched sea bottom for the last time, just three km from Nanaimo. She and several sister destroyers have been sunk as artificial reefs and tourist attractions for divers in recent years, with HMCS Cape Breton to soon follow."
Source: Divers Alert Network (DAN)
Simply put, alcohol and diving are not compatible. Alcohol causes depression of the central nervous system, which impairs judgment and reduces reaction time and coordination. Often the individual is not even aware of the degree of impairment.
A review of more than 15 studies on the effects of alcohol on performance found that alcohol was involved in roughly 50 percent of all accidents in people of drinking age. In Diving and Subaquatic Medicine (Edmonds C, et al., 2002), the authors report that alcohol is associated with up to 80 percent of all drownings in adult males.
It takes time for alcohol to be metabolized and its effects to wear off. M.W. Perrine and colleagues studied a group of experienced divers and the impact of alcohol consumption on their performance. Their investigation found that the ability to perform skills while scuba diving was significantly compromised at a blood alcohol concentration (BAC) of 0.04 percent, which can be reached by a 180-pound man who consumes two 12-ounce beers in one hour on an empty stomach. The study went on to state that even at a lower BAC, situational awareness and protective inhibitions may be reduced.
Recent alcohol intake (along with seasickness, traveler's diarrhea, excessive sweating, diuretic medications and air travel) is a potential cause of dehydration in divers. Dehydration, particularly when severe, is a potential risk factor for decompression sickness (DCS). Diving can also contribute to further fluid loss through breathing dry air and diuresis caused by both immersion and cold. Some symptoms of dehydration, such as fatigue or drowsiness, can even mimic DCS, leading to possible diagnostic confusion.
Alcohol ingestion may also enhance the effects of nitrogen narcosis. Elevated BAC, dehydration and nitrogen narcosis together may result in otherwise preventable accidents due to decreased problem-solving ability.
Many divers appreciate a cold beer, but drinking and diving can turn a safe activity into a nightmare for both the diver and all those impacted by a rescue or fatality. Think twice before combining alcohol and diving.
WOODLAND PARK, N.J. — After several months delay, the ship that helped rescue seven people during The Perfect Storm is scheduled to be sunk off the New Jersey and Delaware coast next week, state officials said Tuesday evening.
The Coast Guard cutter Tamaroa will join other ships forming an artificial reef about 26 miles off Cape May at a ceremony Tuesday, barring bad weather, said Larry Hajna, a spokesman for the New Jersey Department of Environmental Protection Agency.
The 73-year-old ship, which also had a distinguished career in World War II, had been scheduled to be sunk late last year. It was delayed when lab tests confirming the ship was free from cancer-causing PCBs — a prerequisite before sinking — came in later than expected.
The sinking comes a few months after the 25th anniversary of storm, a confluence of three weather systems off the New England coast in October 1991 that generated 40-foot waves and wind gusts over 70 mph.
The Tamaroa’s crew helped save three people on a sailboat before rescuing four of five crewmen of an Air National Guard helicopter that had to be ditched in the ocean when it ran out of fuel during a similar rescue mission. The ship gained fame when its exploits were documented in Sebastian Junger's 1997 book, The Perfect Storm, and three years later in a film starring George Clooney.
News of the Tamaroa's sinking generated significant interest among former crew members. Many would rather see the ship used as a reef than demolished for scrap metal.
The ship already had a decorated history as the Navy's USS Zuni, towing crippled U.S. warships across the Pacific in World War II and aiding in the invasion of Iwo Jima. It was transferred to the Coast Guard shortly after the war and spent almost a half-century conducting search and rescue operations along the East Coast.
The Tamaroa was decommissioned in 1994. A decadelong effort by a group of veterans to restore the ship ended when its hull sprang a significant leak in 2012, causing hundreds of thousands of dollars in damage.
The Tamaroa will join the Navy destroyer USS Arthur W. Radford 120 feet below the ocean's surface on the Del-Jersey-Land Reef, which is managed by Delaware, New Jersey and Maryland.
By Ned and Anna DeLoach
I'm not sure how far off Palm Beach, Fla., we are when the engines slip into neutral and a big inflatable ball dangling 40 feet of line trimmed with lights disappears into the night. I guess it's about four or five miles, and if Captain Dean's calculations are right, we're positioned near the ever-shifting edge of the Gulf Stream where marine life congregates. While the idling boat gently bobs, a dozen fidgety divers sit lined along benches in full gear, waiting for the signal to bail out of the back like paratroopers.
First off the deck, Anna and I make a beeline for the glowing down line — our mother ship for the next hour and a half as we drift in the little-known universe of larval sea life, the great oceanic diaspora of the externally fertilized offspring of reef fishes and invertebrates. The few survivors of the multiweek metamorphosis eventually settle to the seafloor, where they develop into their final adult forms.
Divers, who are inquisitive by nature, are always looking for new ways to experience the wonders of the underwater world. One increasingly popular diving technique, called fluorescence (fluo) night diving, gives divers the ability to observe marine creatures in brilliant, glowing colors invisible to the naked eye.
Fluo diving relies on the property of some marine life to emit longer wavelengths of visible light when illuminated with shorter-wavelength blue light. The term "emission" is very important to understanding the physics of fluorescence. The emission of light differs from the reflection of light that happens when, for example, you take your white light torch on a night dive. In traditional night diving, white light is reflected off of the reef or organism and bounced back to your eyes. Emission light, however, is light that the organism creates and emits back to you. The process is similar to bioluminescence in that the organism creates its own light; however, in bioluminescence the light, which is generated by chemical reaction, requires no excitation light.
To view biofluorescence, fluo divers equip themselves with blue-light torches and barrier filters for their masks (and cameras, if they are doing photography). The barrier filter's function is to block the blue light that is reflected back to the observer from the organisms on which the light is shining. All that would be visible without the barrier filter is a very bright blue light, but the filter is designed to cut off all or most of the wavelengths in the blue part of the spectrum. The intensity of the emission light from the organism is very dim — so dim, in fact, that it is completely overwhelmed by the blue light; but if you block the blue, all you will see are the emission colors.
An anemone emits fluorescent light, unlike the surrounding sponges and corals.
The wavelength of light used in most fluo torches is a narrow band of blue, somewhere between 440-480 nanometers (depending on the manufacturer). Fluo diving differs from ultraviolet (black-light) diving because UV light is in the sub-400nm range. Some companies produce UV torches for underwater use because invisible UV excitation light has the advantage of requiring no additional filters, but researchers have also discovered that blue light is more efficient in stimulating green fluorescent protein (GFP) and its mutations, which emit colors other than green.
Blue light is so effective because (as we all know from our beginner open-water course) it is the only light available at depths beyond about 30 feet, which means that this is the light in which organisms such as coral have evolved over the eons. Most UV light from the sun bounces off the surface of the water, and the light that penetrates makes it only a few inches, rendering UV light an inefficient light source for fluo diving.
Not all marine organisms exhibit the fluo effect, but for those that do the visual demonstration can be dramatic. Some examples of fluorescing species include anemones, a variety of shelled animals, some types of fish, coral polyps and both soft and hard coral structures. The terms "hard" and "soft" coral can be a bit misleading. For example, brain coral is often mistaken as hard coral, but it is considered to be in the long polyp stony (LPS) family of soft coral. The small polyp stony (SPS) family of coral is similarly misrecognized as hard coral even though it is actually soft. These misidentifications are due to the fact that, in both cases, the living coral is made up of tiny soft creatures that live and die building up large stony structures over the course of decades. Interestingly, these two species are the coral subjects that emit the most fluo effects. Examples of soft coral that rarely fluoresce are generally in the Alcyonacea order; it is important to note, however, that in all groups there are exceptions to the rule — just like with people.
Without fluo dive gear it would be impossible to observe the colors of this blenny.
The basic point is that there is great variance in the types of coral that fluoresce, and we have not yet determined all of the rules of this phenomenon. This is one of the allures of fluo diving: You can make your own discoveries as a citizen scientist.
Many people think that fluo diving is done only for views of the spectacular colors or for the purposes of underwater photography. It certainly meets those expectations and can indeed be a life-changing experience, but it is also much more than that. Fluo diving has become an indispensable tool for coral-health research efforts and coral-propagation census analysis. If you come upon a polyp or drifting coral larvae with white light, you will see little or nothing; with the proper fluo diving gear, however, the individual, almost-microscopic organisms will shine in the sand like sparkles in the snow on a moonlit night. Not only is this amazing to witness, but it also provides scientifically valuable data.
Coral reefs are considered the rainforests of the ocean. In normal waters, corals develop a symbiosis with single-celled algae called zooxanthellae, which use photosynthesis to provide food and energy to the coral. When water temperatures rise, the zooxanthellae are ejected, removing the vital nutrients the coral needs to survive and causing "bleaching" of the coral. The coral bleaching that accompanies rising temperatures makes the coral vulnerable to additional stresses that can ultimately destroy the entire reef. Apart from coral bleaching, ocean acidification reacts with the coral's calcium-carbonate skeleton, causing it to break down and dissolve. These effects can be witnessed under white-light conditions, but they are even more dramatic when using fluorescent technologies.
Diving the shipwrecks of the Battle of Jutland had always been an ambition of mine. Having first learnt about the battle at school, it had always resonated with me—hundreds of ships, mighty platforms speeding in excess of 20 knots, firing their enormous guns and, of course, the human tragedy of over 8,000 lives lost.
Twice before had our UK deep wreck diving team, Darkstar, attempted to get to the site, but a combination of bad weather and mechanical problems had so far thwarted our plans. In mid-September 2015, however, a discussion with Mark Dixon, who leads the dive team and owns the project’s 12m long catamaran (also named Darkstar), started a plan that would take nine months to execute. Not only would we once again try for Jutland, but we would do it on the 100th anniversary, and lay a wreath in memory of the sailors who perished over the two days of the battle on 31 May and 1 June 1916.
There are a few places in the world where one can see sharks quite close naturally (without divers changing the natural environment with food), such as the sardine run in South Africa where huge bait balls attract sharks. Being in the right time and place for large migration events like the hammerheads that pass through the Galapagos is another opportunity, and then there is the super lucky dive where a curious shark comes close. But mostly, sharks do not like us. We are big and loud (all those noisy bubbles), and when they see or hear us, they swim away. Sharks have a sensory organ called a lateral line system that allows them to sense movement and vibration in water. We must sound like a freight train to sharks, and they know we are there long before we ever see them, so we often do not see them.
Enter the shark dive, where bait is used to lure sharks to a specific spot and divers can enjoy the spectacle.* Sometimes, the sharks are actually fed by a trained dive guide, sometimes a bucket of bait is opened at the end of the dive, or sometimes the sharks are not fed at all but a container of bait is used to keep curious sharks nearby. For photographers and videographers, these dives are amazing opportunities to get close to sharks, and here are some tips to get the best photos.
As most Atlantic wreck divers know, many of North Carolina’s Outer Bank wreck sites were the result of the "Battle of the Atlantic." During the early stages of Word War II, Germany's marauding U-boats brought their ocean campaign of destruction right on our doorstep, and they proved to be one of the most fearsome and effective weapons in the history of naval warfare. Under the command of Admiral Karl Donitz, Germany’s U-bootwaffe (German for boat fleet) launched their first series of strikes against American shipping in the finals days of 1941. Known as operation “Paukenschlag” (Drumbeat), the attacking force was comprised of five IX class, long-range boats.
Mangled in battle, now covered in coral, the U-352’s snorkel lies separate from the conning tower that once held it.
Between their arrival in US territorial waters, December 27, 1941 and February 6th, 1942, the drumbeaters sank 25 ships. By the close of that same year, U-boat operations along the U.S. continental shelf had swelled into a seemingly unstoppable force that rampaged from Maine all the way into the Gulf of Mexico. My father, as a boy growing up near the Outer Banks, would watch the fires of their victims burn, then fade into the black veil of night. In the span of one year, the U-boat kills reached close to 100, while sustaining only 21 losses of their own.
In response to this hidden threat, allied forces organized convoys with naval escorts. Homeland defense forces deployed long-range aircraft patrols and cruisers armed with depth charges, and at the same time worked diligently to develop more sophisticated sub hunting measures. These measures included everything from improving active sonar systems to radio triangulation and cracking coded intercepted messages. It was the breaking the enigma code that eventually made service aboard U-boats almost suicidal. By the end of 1942, the number of U-boats destroyed stood at 64. During the first months of the following year, 94 boats were sunk, culminating in the fleet’s darkest time, Black May, when 41 subs were killed and another 37 damaged in one month. One of the victims of this onslaught was the U-352.
At 218 feet long, the U-352 was a VIIC design, which included a 88mm deck gun mounted forward of conning tower. Surprisingly, this vessel had not one kill to her credit. Worse yet, on May 9th 1942, the second— and soon to be last—ship she fired on was the US Coast Guard Cutter Icarus. Dogging the U-352's torpedoes, the Icarus made her own attack run, deploying five depth charges which severely damaged the U-boat internally, wrecked the conning tower and blew off the deck gun. Two more depth charge attacks forced the U-352 to the surface where its commander KL Rathke ordered his crew to scuttle and abandon the ship. In the end, 17 of her crew were killed, with the rest taken in to Charleston as prisoners of war.
A Decade of Searching
For a battle that was so well recorded, nobody knew the exact whereabouts of U-352 until Captain George Purifoy (the originator of Olympus Dive Center), Rod Gross, Dale McCullough and Claude Hall (who started the search through extensive research of WWII naval archives) decided to seek the downed sub. Their hunt went on for 10 years before it was found in April 1975, a full mile and a quarter from the original coordinates logged by the Icarus.
Today, the U-352 is one of North Carolina’s signature wreck sites. For divers making the journey to Morehead City, it stands near the top of the list. Even with the dive briefing fresh in your mind, seeing the U-352 materialize off the bottom, sitting with a 45-degree list to starboard, is an amazing sight. Located some 35 miles offshore, the U-352 lies within close proximity of the Gulf Stream, which often times rewards divers with visibility upwards of 100 feet.
Following the descent line toward the bottom, my first impression of the wreck was surprise at it's relatively slender diameter. Living quarters on most medium size attack class warships from this era was far from luxurious. Life on a U-boat with a maximum width of just 20 feet stuck me as incomprehensibly claustrophobic – even when no one was shooting or dropping explosives on you. While still largely intact, most of what you see on the bottom is the remains of the pressure hull as the majority of the U-boat's outer casing has rusted away.
The U-352’s aft rudder shrouded in baitfish.
As I worked the wreck for a few choice images, the non-photographer in me wandered down a different path. Through the years I had the opportunity to dive a large number of wrecks, most victims of storms, collisions with reefs and even a few sunk by German U-boats. But being able to actually rest my hand on one of these man-made predators for the first time was powerful stuff.
Even among experienced Outer Banks divers, the biggest challenge to diving the U-352—as with most area wrecks at depths greater than 70 feet—is waiting for the boat to hook up on the wreck and set the down lines. The procedure calls for a member of the crew to carry a line and physically tie into the wreck. In the U-352’s case, this is a 120-foot swim to the bottom, before anyone else can enter the water. Depending on conditions, the drill can take 15 to 20 minutes. To expedite this process, Olympus Diving Center’s divers are equipped with underwater communication gear. From the bottom, the diver can advise the captain if he needs to move the boat or pay out more line, as well as give a detail report of conditions from top to bottom.
The controlling variable when diving the wrecks of North Carolina’s Outer Banks is the weather. One day it can be great, with calm seas and blue water, while the next day can turn absolutely foul, with either strong winds and rough seas, or just plain grim visibility in the 10- to 30-foot range. The most influential forces of nature is the Gulf Stream, which contacts the eastward protrusion of the banks as it flows northward. As a result of the Stream, summer water temperatures can average in high 70’s, sometimes rising into the in low 80’s, with underwater visibility upwards of 100 feet. On many of the area's wreck sites, there is often enough current to make the use of a down line imperative.
The self-sufficiency mindset is where the diver is fully self-sufficient and approaches the dive with the view that they can perform the dive on their own and would be fully able to complete the dive without a buddy. The approach is summed up by the mindset that if you can’t do the dive on your own then you should not be doing the dive at all.
The other approach is team diving where strong team work and cooperation are the focus of the dive, and you plan to dive with a team of divers, and the team works as a well coordinated whole.
These two approaches seem to have a very different emphasis, and many divers think that they are contradictory. That is, you have to decide whether you have a self-sufficient approach or a team-based approach and that it is a choice of one or the other. Both approaches have their extremists who will go to great lengths to explain why their approach is right and the other approach is wrong.
In some areas, technical diving in the United Kingdom has evolved into a culture of solo diving where many experienced technical divers dive solo. All equipment choices are made on the basis that you will be diving alone or that your buddy will be of no use. Gas planning is based on the principle that it is impossible or unlikely that your buddy will be any use in an emergency and so all procedures are based on individual action.
The team diving approach also has its extremists who focus on teamwork as the primary goal and consider self-sufficiency to be a sign of weak teamwork. These divers will only dive with divers who follow the exact same team procedures.
In reality, these two extreme positions are not very realistic, and when taken to extreme, counteract the very point of the principles. This can cause significant problems, as the advocates of self-sufficiency can refuse to see some of the benefits of team diving, whereas the advocates of team diving refuse to see any benefit in self-sufficiency...
The U.S. Coast Guard cutter George M. Bibb (Builder's No. CG-71) was built at the Charleston Navy Yard, Charleston, South Carolina, and was launched in 1937. She was commissioned on 10 March 1937. The ship was 327 feet in length, with a draft of 12 and a half feet. Her propelling plant consisted of twin propellers powered by geared turbines supplied with steam from oil fired boilers. The first assignment of George M. Bibb after her commissioning was to the Fifth Coast Guard District, with Norfolk as her home port. Sometime in May or June of 1937 her named was shortened to Bibb.
The issue with diving—at least for this discussion—is that as a diver descends in the water column, he or she has no option but to breathe compressed gas. Because of this, the inert gas contained in whatever is being breathed is stored in the diver’s body. This is sometimes called inert gas uptake.
At the end of a dive, on the way back to the surface, the process is reversed, the stored inert gas is released by the diver’s body. This is called inert gas elimination, or more simply, decompression. These two processes are part of every dive—even seemingly benign sport dives to shallow depths for short periods of time. Every dive really is a decompression dive.
When diving, tracking and understanding how to best manage inert gas uptake and decompression within safe limits, is second only to making sure one has something other than water to breathe. If we “get it wrong” and remain at depth too long, ascend too rapidly, breathe the wrong gas, or simply have a bad-luck day, we run a higher than usual risk of suffering decompression sickness (DCS). Getting bent, the colloquial term for DCS, is a collection of disorders caused by a portion of the inert gas stored in a diver’s body bubbling out of solution too rapidly. The consequences of being bent run the gamut from nausea, fatigue, mild joint pain and dizziness all the way through paralysis and death.
Often referred to as slugs due to their evolutionary path, the grand designs of nudibranchs are as fascinating and varied as there are slugs themselves. Each one of them has evolved in a special manner to survive and reproduce in the many different and challenging habitats in which they are found. Cold water to warm water, benthic or pelagic and at every depth, nudibranchs occur globally and have even been found in brackish rivers.
Shooting photos of sea slugs is often the way many macro shooters start out. They shoot various finds from each dive, then look them up in a marine species identification book. This often results in a collection of basic ID photos. While this is a common path for an underwater photographer to take in learning the craft, it often sets one up for bad habits down the road. There eventually comes a time when shooters have the desire to take their images to a different level, but breaking the habit of shooting ID photos can often be a challenge. One of the things that has helped me to shoot more creative images of nudibranchs began with learning about them first.
Knowing the food source of a nudibranch is an elementary yet effective way for hunting nudibranchs. Tunicates and algae are a great place to start, followed by hydroids and so on. It also helps to know a little about the anatomy and biology of nudibranchs.
Mollusks comprise a group of soft-bodied animals that includes snails, clams, and sea slugs. The most common characteristic of most mollusks is their shell. One of the largest groups, the snails, is renowned for their shells. Snails are univalves, which means they have one shell. And it is this shell that for many people is the epitome of the ocean. There is perhaps no other ocean treasure that displays more diversity and beauty than the shell. Conchology, the study and collection of shells is a popular hobby the world over. The bivalves, or two-shell mollusks include the clams, scallops, and oysters. It is the oyster that is responsible for producing the most coveted of the ocean's treasures - the pearl. Still other mollusks have lost their shells altogether. The octopus, the squid, and the sea slugs have evolved their own survival strategies to replace their protective armor. Indeed, it is due to the absence of a protective shell the octopus has evolved the largest and most complex brain of all the mollusks. Below is a listing of some of the most common mollusks found on the world's coral reefs.
Beaked whales are members of the family Ziphiidae, the second largest family of cetaceans (which includes whales, dolphins and porpoises), however many of the 22 species of beaked whales are among the least known or understood mammals in the world. This lack of knowledge is highlighted by the fact that three new species of beaked whales have been discovered in just the last two decades.
To see beaked whales at sea is such a rare event that many researchers devoting their life to study cetaceans have never seen one. Living in deep waters, usually far offshore, these creatures spend some 92% of their time underwater, invisible to humans. Beaked whales break diving records, feeding at depths that can reach three kilometers and last up to 2 hours. After these diving feats, they rest, performing shorter and shallower dives with brief surfacing intervals. These behaviors, together with the fact that beaked whales live in small groups, are not usually attracted to boats, and do not perform aerial acrobatics as much as dolphins, mean that beaked whales are not easy to detect at sea. Moreover, many beaked whales have variable color patterns that may be shared by other ziphiid species, challenging the identification of beaked whales at the species level during sea encounters, when often only a short glimpse of their body is achieved.
Quality dive accessories exist to make diving not only safer but also simpler and more enjoyable. Whether it's an easy-to-use signaling device to get your buddy's attention, a rugged cutting tool to get you out of a sticky situation or a bright light to illuminate a dark place, an effective accessory might be just what your gear bag is missing.
Less Is More
While a few handy accessories can enhance your dives, carrying too many may do the opposite. Looking like a Christmas tree underwater with countless shiny gadgets hanging from your BCD might make you a hit around the holiday season, but it will also make you work harder while swimming and limit how quickly you can reach what you need. More dangling gear also increases your risk of being entangled in loose line, nearby buddies or innocent marine life. Thoughtfully consider what tools or gadgets you'd like to take with you on each dive.
Few problems in diving can be as stressful and dangerous as underwater entanglement. Even when you're not in immediate danger, having a cutting device — or better yet, more than one — within easy reach will put your mind at ease and let you focus on having fun. Whether you use it to trim a few inches off your weight belt before you gear up or to free your buddy from some fishing line he swam through during the dive, a cutting device is one of the most important accessories you can have on hand.
Trauma shears and fully serrated knives can make quick work of thick lines and wire, while hook-shaped cutting devices are most useful for cutting thin lines with one hand. Corrosion resistance is an important factor when choosing a cutting tool, and devices made of titanium or high-quality stainless steel will generally last the longest. Any device that is simple, robust and easily accessed can be useful in an entanglement and will make dealing with problems that arise underwater minor annoyances rather than emergencies.
Whether you need to let your buddy know you're running low on gas or you want to show her the elusive albino frogfish you just found, attention-getting devices such as tank
Among the most useful dive accessories are tools that can help you get your buddy’s attention, free yourself from an entanglement and illuminate dark places.
bangers and underwater maracas can be incredibly useful. These accessories come in a variety of forms, from elastic bands with hard rubber balls you use to strike your tank, to waterproof containers filled with metal beads that you shake.
"Nobody understands the allure of the sea more than the U.S. Coast Guard, but we also see the tragic results when people underestimate the hazards. The adventure and thrill of diving are appealing to many, but the ocean is an unforgiving environment — and even less forgiving to those who recreate beneath the surface."
— Rear Adm. Karl Schultz, commander of the 11th Coast Guard District
Recreational diving is by and large a safe activity, but when accidents occur the outcomes are often frightening and can be fatal. The beautiful blue world below can quickly become hostile for divers who lack adequate training, are in poor physical condition, use improperly maintained equipment or are otherwise unprepared.
Although the U.S. Coast Guard does not have regulatory authority over recreational diving as it does for recreational and commercial boating, Coast Guard search-and-rescue crews are frequently called on to assist when divers are lost or in trouble. In the aftermath of a dive injury or death, the Coast Guard marine casualty investigators work with other public health and safety organizations to identify what went wrong and evaluate how to prevent future accidents.