 Editorial
By Alex Brylske Photo by Joseph C. Dovala
The Female Persuasion
When I started diving in the mid-1960s "lady" divers, as we called them back then, were as rare as hen's teeth. Not that there weren't any. Even then we heard stories and read articles about the likes of the "Shark Lady," Dr. Genie Clark, and knew from the TV series, "Sea Hunt," that an amazing female diver named Zale Parry was lurking around beneath the waves with us "men." (I was 13 at the time.) I'd even heard of a lady diver named Norine Rouse who actually owned a dive operation in Florida, and was noted for holding her own with anyone possessing a Y chromosome. But these, in our testosterone-marinated world, were anomalies.
In this month's feature, "Diving Beyond Small and Pink: Women and the Sport of Scuba," Linda Lee Walden brings us firmly into the 21st century. Today about three in 10 divers are "of the female persuasion," as my cavemen dive buddies used to describe them. And that number is growing. Interestingly, the professional ranks of divers appear to have an even higher female proportion, something that I see as a very hopeful sign for our industry.
Of course, the diving culture is just a microcosm of society. And while we've made great strides in gender equality over my lifetime, there's still a way to go. But unlike in society, I don't think our problem with gender inequity stems from discrimination. In our case, it's misperception. Try as we might, diving still holds the stigma of being deep, dark and dangerous. The machismo image of the past hasn't faded just yet, at least not completely. Granted, spitting in a mask, and the postdive public nose-blowing ritual may never endear diving to females (or males) with delicate sensibilities. Yet, for those who are willing to look beyond the yuck factor, and learn how truly safe and simple diving is, the rewards are endless.
The real challenge for diving is how to turn that three in 10 to reflect more of the overall five in 10 population norm. Certainly there's a lot to be said for continuing to present diving as an activity in which gender is irrelevant. After all, brute strength rarely contributes anything to the underwater experience. Making that point, along with what the underwater world has to offer in beauty and wonder, will hopefully attract more females to our ranks.
Yet, to turn the trickle of a few more female divers into a flood requires something more, and I believe that means turning our attention to youth. In recent years it's become popular for companies to hold "take your daughter to work days." Certainly, this brings dads as well as moms closer together with their daughters, but it also accomplishes another more subtle goal. It expands the horizons of many young girls and inspires them to consider careers that might otherwise never occur to them. Well, why not take the lead and try the very same tactic? Take your daughter diving. Pink isn't just a color for dresses; it makes an attractive wet suit, too.
Buddy Lines
Marine Parks and Knives
Marine Parks and Knives
Good article by Lynn Laymon on why divers should carry cutting instruments ("The Cutting Edge: Every Diver Should Carry One," Dive Training, October 2009) and the wide selection of knives and other tools currently available. If you accept Lynn's premise, and I certainly do, that "Every diver should carry one," the article offers sound advice to help in the selection process.
As part of that process, divers need to consider that many marine parks and dive operators throughout the world now prohibit divers from carrying knives. Their rationale is that if you don't have a knife you're less likely to poke around in places where you shouldn't poke around. Fair enough, but that leaves divers without a means of cutting monofilament fishing line, netting and other forms of entanglement we occasionally encounter on our dives. While rare, entanglements can go from annoying to life-threatening very quickly, and diving without a means of cutting yourself free is recklessly unsafe as far as I'm concerned.
Marine park and dive operators may look more kindly on shears or line cutters but my solution for years has been to carry a small, folding, titanium dive knife in my BC (buoyancy compensator) waistband pocket.
Keep up the good work.
John Bowden
Marietta, Georgia
Praise for Conscientious Diving
As a dive professional and a naturalist, I find the letter "Lighten Up, Divers" (Buddy Lines, Dive Training, October 2009), very disturbing and I am amazed these attitudes still exist in the 21st century. I am curious as to the sources of the "studies" referred to in the letter. Also, I wonder about the basis of Mr. Heimer's "scientific" shell collecting. I would expect a scientist to be more open-minded about the many sources of ocean degradation. He simply points fingers and denies the consequences of his own actions.
People dive for a wide variety of reasons, some perhaps more noble than others. The scuba diving community has been lucky to be largely self-regulated. If we want this to continue we need to ensure that our impact is minimized as much as possible and, yes, be ambassadors in protecting the oceans. The "Take only pictures, leave only bubbles" mantra, which Mr. Heimer so easily dismisses, is a necessary and responsible way to dive. This is especially true in Caribbean destinations, largely due to the volume of tourists.
Randy Timms
Peterborough, Ontario
Dive Into Fitness
One of the first lessons I learned when taking my first scuba class was the need to be physically fit. For example, I had to demonstrate that I could swim 300 yards with ease.
One of the first shockers of my scuba career after getting certified was how many divers are nowhere close to being physically fit. In fact, for a while obesity almost seemed to be a requirement. Let's face it: Not many of us carry "abs" that bear a striking resemblance to Poseidon (Greek god of the sea). I quickly came to accept the fact that diving accommodates all sorts of shapes and sizes, and that's one of the things that makes it great.
But certainly a diving community in good physical shape is one that can maximize the enjoyment of plying the underwater realm. I would challenge divers of all shapes and sizes to get into reasonably good condition and make the effort to stay there. It can make your good dives great, and ensure that not only your dives last longer but your ability to dive as well.
Dave Tomlin
Tallahassee, Florida
A Refreshing Respite
I thoroughly enjoyed your story on scuba experiences ("Why We Dive: What Does Scuba Mean to You?" Dive Training, October 2009) and wish to share my own answer.
Scuba for me is about getting away. Away from everything. And is there a world more opposite of the one on the surface of the Earth than the one under the surface?
Every time we sink under the surface we venture into the aquatic world — someone else's world. It is peaceful, fascinating and only mildly challenging.
It is also unusual. We divers are part of a relatively small fraternity. We engage in something that most others can only dream about. Maybe that's what binds us so firmly.
And like your story said, self-confidence should not be overlooked. We train to be a diver, and after our classes and studies, after we clear our mask in an open-water environment for the first time and overcome the anxiety of entering a world that is foreign to us, we feel better about ourselves. We confirm that we can do it. We can be a diver.
Ellen Fulk
Denver
 DNN
dive observer
INVASIVE ZEBRA
MUSSELS NOW
REACH INTO TEXAS
Zebra mussels, the invasive water critter feared for clogging intake valves, cutting unprotected feet and devouring nutrients fish need to survive, has been confirmed for the first time in Texas.
Tests recently revealed that the freshwater species Dreissena polymorpha, native to Eastern Europe, is now in Lake Texoma, a 93,000-acre (37,200-hectare) lake straddling the Texas-Oklahoma border.
Divers often use Lake Texoma although there is not a designated diving area, said Bruce Hysmith, Texas Parks and Wildlife Department inland fisheries biologist for Lake Texoma.
Zebra mussels originated in the Balkans, Poland and the former Soviet Union, and were first introduced in North America in 1988 in Lake St. Clair, a small water body connecting lakes Huron and Erie.
Their ability to survive in a variety of environments has surprised some.
"When they were first discovered in the '80s, we were told they couldn't survive in water above 60 degrees [Fahrenheit], so we didn't worry about them [in Texas]. I guess they were wrong," Hysmith said.
Divers can help slow the spread of zebra mussels from one water body to another by practicing the following steps when leaving any water suspected of having zebra mussels.
• Drain all water from the boat including such things as the engine, bilge, livewells before leaving the lake.
• Inspect the boat and trailer and remove any zebra mussels, vegetation or foreign objects that are found.
• Wash your boat and trailer at a commercial carwash using high pressure and hot soapy water. Hot water, 140 degrees Fahrenheit (60 degrees Celsius), will kill zebra mussel veligers (juveniles), and when the water from the carwash goes through a waste water treatment plant the process should kill any remaining mussels.
• Open all compartments and livewells and allow the boat and trailer to dry for a week before entering another water body.
Divers can also help by reporting sightings of suspected zebra mussels to the Operation Game Thief (OGT) toll-free hotline at (800) 792-4263. OGT is Texas' wildlife crime-stoppers program, a function of Texas Parks and Wildlife Department's Law Enforcement Division.
In Virginia, where zebra mussels were discovered in an abandoned quarry lake in 2002, officials encourage divers to clean all diving equipment in a saltwater bath (1/2 cup per gallon) or with warm tap water (104 F [40 C]). All sediment and gritty organic materials should be removed; they could actually be zebra mussel veligers.
Ensure that all equipment remains completely dry for at least 24 hours before being used again. Pay special attention to those areas and equipment that can hold water.
For more information, visit www.
protectyourwaters.net/hitchhikers/mollusks_zebra_mussel.php or www.dgif.
virginia.gov/wildlife/zebramussels.asp.
EXPANSION OF
THUNDER BAY
SANCTUARY OK'D
BY HOUSE
The nation's first Great Lake marine sanctuary would grow by more than eight times and nearly double in shoreline miles under a bill passed September 29 by the U.S. House of Representatives.
H.R. 905 expands the area covered by Lake Huron's Thunder Bay National Marine Sanctuary to 3,722 square miles (9,677 sq km) of water and 226 miles (362 km) of shoreline, up from 448 square miles (1,165 sq km) of water and 115 miles (184 km) of shoreline. The expansion adds an additional 180 shipwrecks to the sanctuary and boundaries that include waters off Alcona, Alpena and Presque Isle counties in Michigan and east to the international boundary with Canada. H.R. 905 now awaits consideration in the U.S. Senate, where Sen. Carl Levin (D-Michigan) has introduced companion legislation.
Sanctuary designation protects the area's underwater cultural resources, prohibiting the removal of items from all shipwrecks. Reports from local divers are used to enforce the regulations, which are carried out by the U.S. Coast Guard, Michigan Department of Natural Resources, Alpena County Sheriff's Marine Patrol and Michigan State Police.
Thunder Bay was declared Michigan's first Great Lakes Bottomland Preserve in 1981, and in 2000 became the Great Lakes' first national marine sanctuary. The sanctuary is a federal-state partnership with a focus on preserving the large collection of underwater cultural resources.
In 2005, National Oceanic and Atmospheric Administration and Michigan established the Great Lakes' Maritime Heritage Center in Alpena, Michigan, to allow visitors to learn about Great Lakes' maritime history, explore shipwrecks via live satellite feed, and see how archaeologists continue to preserve the historic sites.
The Thunder Bay Sanctuary Advisory Council, a 15-member group, recommended the sanctuary be expanded. Steve Kroll of Great Lakes Divers in Rogers City, Michigan, is chairman of the council.
For more information, visit thunderbay.noaa.gov/.
World's First
Shark Sanctuary Established
The South Pacific nation of Palau has established the world's first shark sanctuary — banning commercial fishing of sharks in 237,000 square miles (616,200 sq km) of ocean surrounding Palau's 200 islands and its 20,000 inhabitants.
Sharks are hunted for their fins, which are coveted in soups as an Asian delicacy.
Johnson Toribiong, Palau's president, announced the commercial shark-fishing ban at the United Nations General Assembly, saying "the strength and beauty of sharks are a natural barometer for the health of our oceans."
Sharks often become snared in nets meant for tuna, which remain in high demand among consumers. About 10.7 million blue sharks are killed annually for their fins, many of which are sold at the Hong Kong shark fin market, according to a report from the International Union for the Conservation of Nature.
"President Toribiong's action set a clear and powerful example to the rest of the world," said Matt Rand, director of the Pew Environment Group's Global Shark Conservation Campaign. In addition to declaring the sanctuary, he called for a global moratorium on the finning of sharks as well as an end to deep-sea bottom trawling and the destruction of vulnerable ancient coral ecosystems. "Small island nations have a unique resource that they need to maintain and nurture: the ocean and the life within it. Short-term economic needs have pressured some island nations to overexploit this resource. Palau, however, has decided to take the path of ocean stewardship, building on the desire of visitors to see the wonderful marine environment that it has preserved."
Among the supporters of the sanctuary is Sam Scott and his Sam's Tours dive operation in Palau. For more information, including Toribiong's entire speech to the United Nations, visit sharksanctuary.blogspot.com and www.sharksanctuary.com.
SOUTH ATLANTIC Fishery Restricts Bottom Trawls
A plan to protect more than 23,000 square miles (59,800 sq km) of deep-sea coral from North Carolina to Florida from destructive fishing gear has been approved.
The South Atlantic Fishery Management Council's recently voted to restrict the footprint of bottom trawls — one of the most nonselective fishing gears in use — and help to restore the long-term productivity of commercially valuable fish that take refuge in the rare corals.
"This landmark decision is a win for the oceans and those in the Southeast who rely on it for their livelihoods," said Dave Allison, senior campaign director at Oceana. "The crushing of these ancient coral reefs would be a serious loss to the ocean ecosystem and could threaten the survival of golden crab and wreckfish fishermen that catch other species on these deep reefs."
The decision will now be sent to the National Oceanic and Atmospheric Administration for its approval and implementation. The new regulation is expected to take effect by the end of 2009.
Deep-sea corals off the Southeast coast include hundreds of pinnacles up to 500 feet (152 m) tall. These corals provide homes for a variety of marine species, including sponges with unusual chemistry currently in testing to develop drugs for the treatment of cancer, heart disease and for other medical needs.
For more information, check out www.safmc.net/.
WASHINGTON SITES TO GET DIVE BUOYS
Nineteen mooring buoys will be installed at dive sites in five counties around Puget Sound and Hood Canal in Washington, state officials have announced.
The announcement is the culmination of efforts involving the State Department of Natural Resources and the Washington Scuba Alliance (WSA) which began lobbying for the buoys three years ago. With permanent buoys, boaters won't need to use anchors, which can uproot vegetation and destroy reefs.
"The Scuba Alliance has volunteered time and money to make this happen," said state Commissioner of Public Lands Peter Goldmark. "I think we have a solution with these buoys that supports great diving opportunities, while preventing the damage that can occur when temporary mooring drags through eelgrass and other sensitive aquatic habitats."
Other damage has occurred from propeller scour when vessels are anchored in shallow water.
DNR has worked with the WSA on approving the most appropriate locations for the buoys. The majority of these popular sites are only accessible by boat. In addition, the design of the buoys, lines and installation methods will result in an effort that provides boating access while protecting the marine habitat below. The current best practices include:
• A helix anchor that drills into the seabed, minimizing disturbance.
• A midline float to prevent anchor line dragging at low tide.
• Placement in approved water depth to eliminate "prop scour" to vegetation and habitat.
• Annual maintenance requirements.
The installed buoys will be available for use by the general public on a first-come, first-served basis and will be prominently marked as such.
For more information, check out www.wascuba.org.
QUINTANA ROO
PLANS UNDERWATER MUSEUM
Mexico's Quintana Roo plans to establish an "underwater museum" to take pressure off natural habitat.
The "Subaquatic Sculpture Museum" will be set up in the West Coast National Park in the southeastern state of Quintana Roo, on the Yucatán Peninsula. Organizers planned to submerge four sculptures in November and up to 250 figures by 2010. When finished, about 400 sculptures will be in place.
Mexican authorities are trying to strengthen the health of their coral reefs to make them more resistant to hurricane damage. The Intergovernmental Panel on Climate Change has warned that extreme weather phenomena, like hurricanes, will become more intense and frequent as a result of global warming. The panel also predicts higher acidity of ocean waters and consequent bleaching of coral, which can kill it.
The museum is expected to draw marine creatures as well, much like it has done for smaller artificial reef projects. After a cruise ship destroyed 1,650 feet (500 m) of coral in 1997, park administrators in 2005 set up an alternative dive site — 110 hollow domes and concrete structures in layers to create an artificial habitat in the area known as Sac Bajo. So much marine life moved into the domes that they are now considered a must-see attraction.
Each sculpture will be human-sized, with a base of 44 square feet (4 sq m). Theme-based galleries are planned as well.
One of them, "The Dream Catcher," will be the figure of a person who sorts bottles that arrive with messages sent by castaways. Another will be "Coral Collector." Also in the works is a series of sculptures depicting an army of Maya indigenous warriors.
TEXAS DIVE SHOW FEBRUARY 12-13
The Texas Dive Show is scheduled for February 12-13 at the Embassy Suites Dallas-Frisco/Hotel, Convention Center & Spa, 7600 John Q. Hammons Drive, in Frisco, Texas.
Show hours are set for 5-8 p.m. Friday and 9 a.m. to 5 p.m. Saturday. Programming and other details will be announced soon. For updates, check out www.divechronicles.com/texas.
UNDERWATER
INTERVENTION SET FOR FEBRUARY 9-11
Underwater Intervention is planned for February 9-11 at the Ernest N. Morial Convention Center in New Orleans.
Topics for seminars at the technical conference include remotely operated vehicles, commercial diving and training, manned submersibles, marine construction, scientific research affecting underwater operations, and sonar and acoustics.
Exhibits and other programs are planned. For additional details, call (800) 316-2188 or visit www.underwaterintervention.com.
WINDY CITY EXPO FEBRUARY 19-21
Our World-Underwater, 40th Annual Consumer Dive and Travel Exposition, is scheduled for February 19-21 at the Donald E. Stephens Convention Center in Rosemont, Illinois.
The three-day show includes workshops on underwater photography, closed-circuit rebreathers, how to get started in video production, and a closer look at technical diving. Other programs include "Titanic's Last Secrets" by Richie Kohler and "Pirates of the Caribbean: Excavation of Capt. Kidd's Shipwreck" by Charles Beeker. Exhibits, a film festival, silent auction and book signings also are planned. For a look at the entire program agenda, visit www.ourworldunderwater.com or call (708) 226-1614.
The World
is Blue: How Our Fate and The Ocean's are One
Marine scientist Sylvia Earle explains in her latest book how "50 years of destructive oceanic change is threatening the very existence of Earth."
In "The World is Blue," Earle portrays a global ecosystem on the brink of irreversible environmental crisis, unless action is taken immediately.
Weaving together anecdotes of her years of ocean exploration with the latest findings about the state of the seas, Earle shows how, since the mid-20th century, we've done untold damage to a vital system that has evolved over 3.8 billion years.
"What is most troubling, perhaps," writes Earle, "is the profound, widespread ignorance about the ocean and its vital importance to everyone, everywhere, all the time. It is not just the fact that less than 5 percent of the ocean has been seen, let alone explored. Even what is known to scientists is not widely appreciated by the public, and certainly not by most policymaking officials."
The ultimate goal, Earle says, is to find responsible, renewable, sustainable strategies that will restore the health of our blue world. These include smart aquaculture and smart seafood choices; plans to protect biodiversity and to mitigate and recover from the effects of climate change, new technologies to map, photograph and explore the 95 percent of the ocean we have yet to see; and — Earle's wish — a global network of marine protected areas, "hope spots large enough to save the ocean, the blue heart of the planet." At present, less than 1 percent of the total area of the sea is protected.
The 320-page hardcover book, published by National Geographic, comes with 30 color photographs and four maps. For more information, visit your local dive store or call the National Geographic Society at (888) 225-5647.
The Northwest
Dive Guide: A scuba handbook for
BC, Washington
& Oregon
Cold-water diving is more gear-intensive than warm-water diving, but many divers find the diversity of marine life and panoramic beauty of the world below the water line a delight to explore.
Try the shallow waters of British Columbia's Hornby Island for a cold-water shark dive where spiny dogfish zip around like short-fused rockets and you have a good chance of spotting a blunt nosed six-gill shark. Or visit Sund Rock in Washington, a marine protected area sheltering wolf eels, sea whip beds, various shrimps and crabs and the occasional wandering giant Pacific octopus.
In "The Northwest Dive Guide," master scuba dive instructor and Northwest diving tour guide Mike Hughes shares more than 300 dive sites in British Columbia, Washington, Oregon, Idaho and Montana, including drift dives, wall dives, freshwater dives and wrecks festooned in plumose anemones and patrolled by huge rockfish.
The book also contains training tips, information on local dive operators and shops, and dry land advice such as where to go for a meal after a dive plus nearby attractions for nondiving traveling companions.
For more details, ask your neighborhood dive shop or call Harbour Publishing at (604) 883-2730.
 No Dumb Questions
By Alex Brylske Photo by Barry & Ruth Guimbellot
Post-Dive Headache, Underwater Fishing and Regulator Freeze-up
Q:Mort Weber wrote with a problem that's more common than you might think. "I've been around boats my whole life, but a few weeks ago I made my first boat dive as part of an Advanced Open Water class. I experienced no problem on the way to the dive site, and the dive was deeper than any I've made before, but otherwise not especially stressful. I certainly didn't feel like I was working hard. My problem started on the way back. I had absolutely no symptoms of seasickness, and I've only experienced that before in very rough seas. (The day of my dive was extremely calm.) Still, no sooner than the boat pulled anchor I began experiencing one of the worst headaches of my life. A few minutes later I began vomiting, and did so at least three or four more times before reaching the dock. But that wasn't the end of it. The headache lasted another four or five hours. It got so bad that my dive buddy had to drive me home. I was really concerned that I might have the bends, but my computer showed that I was nowhere near the limit. By morning I was fine again, and in speaking to more experienced divers, they said that it was from excessive carbon dioxide. What do you think?"
A:We'll certainly never know for sure why you experienced the problems you reported, and given your headache symptoms it's no surprise that your friends suggested carbon dioxide as a culprit. The condition you're referring to is actually called hypercapnia. Indeed, that could be what you experienced. Many divers think that hypercapnia can happen only on dives involving lots of exertion (carbon dioxide production). But that's not so. The mere act of breathing underwater is stressful enough to induce high levels of CO2. (Actually, some individuals are especially prone to retaining higher levels of carbon dioxide than normal.) The increased breathing resistance and dead-air space of scuba equipment, reduction in lung volume due to immersion-induced fluid shifts and the increased resistance from breathing higher density gas at depth all conspire to increase a diver's CO2 level. In fact, even without performing any work, a diver's breathing resistance doubles by the time they reach 100 feet (30 m) for no other reason than being underwater. (For more insights on this phenomenon, take a look at a feature article I wrote, "Underwater Breathing and the Role of Carbon Dioxide," Dive Training, June 2008.)
Still, carbon dioxide might not have been the reason for your problem, after all. Headache is also a classic symptom of contaminated air. Was there anyone else on board who got his tank filled from the same source as you? If so, it would be interesting to determine if they experienced similar problems. There's also the possibility that exhaust fumes were the cause. Personally, I find diesel fumes much worse than gasoline fumes when it comes to inducing a headache, which is why I avoid like the plague the stern of any boat that's underway.
Still, there's an issue that's rarely considered, yet recent evidence points to it as a probable cause of headaches in many divers. And it has nothing to do with carbon dioxide or any other gas; it involves anatomy. A few years back an article in the British Journal of Sport Medicine brought to light that scuba diving can induce severe headaches because of stress placed on the jaw, specifically the temporomandibular joint (TMJ). The stress is caused by the constant pressure of biting down on a regulator mouthpiece, and the problem has been seen in many divers who otherwise have never experienced a TMJ symptom before diving. If your headache symptoms persist once you rule out the contaminated air scenario, you might consider a trip to your dentist to see if the TMJ issue could be a consideration.
Finally, I'd also suggest that you keep a close eye on your hydration level. Dehydration can bring on a headache even though you may not feel thirsty. In fact, never use thirst as an indicator of hydration. The only reliable test is to watch your urine. You're well-hydrated only if your urine is nearly colorless.
Q:Damion Worthman sent in a question that has to do with fish. "I was in my doctor's office the other day and came upon a copy of your magazine. I'm not a diver, but I am an avid fisherman. After reading some of the articles in Dive Training, I'm now considering taking the plunge — literally — and getting scuba certified. Of course, my main interest is catching fish, which in diving I know normally means spearfishing. However, I was wondering if I was diving — and didn't happen to have a spear gun — if I could keep a net with me and capture them by hand? I know this is nearly impossible from the surface with a dip net, but with the freedom diving offers, is that possible underwater?"
A:The short answer is that anything is possible. However, I'm afraid your efforts will be fruitless because of something called evolution. It's hard for land-based creatures with only five senses to imagine, but fish go us one better (and sharks, with their electro-sensitivity, even one more). You see, fishes have a sense that some have described as "distance touch." It's part of what's termed their acoustico-lateralis system.
Detecting motion in air isn't very effective because air is a highly compressible medium. Water, however, is a completely different story. So, fish have evolved the ability to use the relative incompressibility of water to their advantage. The distinct line you see along the sides of many species of fishes isn't there for show. It's actually a highly effective sensory structure called the lateral line. Inside the lateral line lie receptors called neuromasts, each of which is composed of a group of hair cells. (These hair cells are like those found inside the vertebrate inner ear, indicating that the lateral line and the inner ear share a common origin.) The hairs are surrounded by a protruding jellylike structure called a cupula. Both bony and cartilaginous fishes normally have lateral line canals, in which the neuromasts are not directly exposed to the environment, but communicate through canal pores. Another side note is that these neuromasts may appear individually at various sites on the fish's exterior.
The lateral line is the organ that allows fish in a school to move in unison, even if the visibility is zero. What this also means is that fish are aware of the slightest motion and change in water pressure. So catching them in a net underwater would be no more effective than trying to do so above. My suggestion is to nix both the net and spear gun and capture your fish with a camera. It will be far less frustrating.
Q:Cold-water diver Bill Flanigan had an equipment-related question. "Much of the diving I do is in Midwestern quarries where the water temperatures below the thermocline are usually around 42 degrees F[ahrenheit (5 degrees Celsius)]. Could you explain what actually happens when a regulator freezes up and freeflows, and at what water temperature does this become a concern? Do I need to be concerned about regulator freeze-up and freeflow? Should I be using a cold-water regulator for this type of diving?
A:Under certain cold-water conditions, scuba regulators can freeflow unexpectedly, creating an often frightening and potentially dangerous situation. To avoid the problem, many manufacturers offer regulators, or adapterss for regulators, that prevent this from happening. But why does this happen in the first place?
While fresh water may freeze at 32 F (0 C), there's really no set temperature at which a regulator freeze occurs. However, the colder the water, the more likely it is to happen. Some manufacturers use 40 F (4.5 C) as an arbitrary point to define conditions in which freeflow due to icing is possible. In addition, water can remain liquid below its normal freezing point — in some cases to as low as 28 F (-2.2 C) — depending on its salinity, and if and how quickly it's moving. So, the actual temperature at which a regulator will experience this sort of problem varies.
A first-stage freeze-up is the most common type. In this case, water inside the first stage freezes because the expanding air moving through it absorbs heat (similar to the way decompressed air makes your refrigerator work). With the first stage frozen open, the second stage becomes overpressurized and it freeflows. (Regulators are designed to be "fail safe," meaning that in the event of a malfunction they will allow air to escape, not cut it off.) To prevent this from happening, some regulators have an "environmental seal" that prevents water from entering the first stage. Because the second stage is the one experiencing the problem, though, many divers mistakenly think that it's the source of malfunction.
On occasion, second stages do freeze up but this normally happens at the surface when the air temperature is freezing or near freezing. On inhalation, the expanding air from the tank drains heat (again, like your refrigerator) lowering the ambient temperature. If there's any moisture present, as might be the case if you've been breathing from the regulator, it can freeze the second stage in an open position, causing a freeflow. However, if you encounter a situation like this, such as when ice diving, there's a simple solution: Remember not to breathe from your regulator until it's fully submerged.
As to whether you should purchase a regulator with an environmental seal depends on whether you have experienced a regulator freeflow, and whether you plan to dive during winter. If the answer is yes to either, it's a good idea to consider.
Always Learning
What We Know,
What We Do:
The Teacher Learns a Lesson
Story and photos by Marty Snyderman
In most respects the dive was fairly typical. It was the first dive of the day and the divemasters had separated us into two groups. My group entered the water first. Throughout the dive we rode a slight current and our deepest depth was only 50 feet (15 m). The visibility was excellent and there was plenty to see so it felt like the time passed quickly. At the 50-minute mark, the divemaster gave the six divers in our group the signal to ascend for our safety stop, and our dive ended as planned.
Once I was back on board the dive boat and had removed my gear, I began attending to my camera system. After I gave it a good rinse in the camera bucket, something I do after every dive when a rinse bucket is available, I walked toward the camera table and realized there was some commotion on the swim step. Several of the divers that were back on board were yelling to the crew and pointing at a diver on the surface who appeared to be in some distress.
The diver was on the surface, but he was not wearing a mask and his regulator was not in his mouth. As I moved toward the back deck to see if I could help, I realized that the diver had his fins in his left hand, and that he was not holding onto the tag line. While he appeared to be doing everything wrong, he probably wouldn't have been in any trouble if he had inflated his buoyancy compensator, but either that was not possible for some unknown reason or he wasn't thinking clearly. Things were starting to get a little tense as the diver swallowed a little seawater. He was coughing and showing some signs that he was beginning to lose control of the situation.
At that moment the divemaster jumped into the water to provide assistance, and things quickly came to an uneventful end, as the divemaster and crew got the situation under control in a matter of seconds. As I watched the assisted diver climb out of the water, I realized that it was the same diver who had recently completed his divemaster course. He had been recognized for that accomplishment during the predive briefing. As you likely suspect, the rescued diver was both embarrassed and angry with himself.
As I am prone to do when I see or hear about any diving mishap, I analyze the situation to better understand exactly why things unfolded as they did so that I might learn from someone else's mistake. I have made plenty of mistakes in my life; might as well see if I can avoid one or two.
As I dissected this event I concluded that the diver had probably gotten complacent. I couldn't be sure that I was right in my assessment, but I did know that the diver absolutely knew better than to remove his mask and regulator once he had removed his fins. He should not have let go of the tag line either, although that might have resulted from his effort to replace his mask and find his second stage. The plain and simple truth is that the sequence of events that led to this diver's trouble occurred because he ignored good diving fundamentals that he had surely been taught in his basic certification class, in his recently completed divemaster course, and that were once again emphasized during our dive briefing. Clearly, he knew better, but he didn't practice solid diving fundamentals.
Arriving at that conclusion, I smugly decided that in some respects this diver deserved what happened, and that I would never do such a thing. Little did I know.
'Karma-gram for Marty'
Later that same afternoon I packed up all of my clothes, diving gear and camera equipment, and moved from a hotel on one end of the island to a hotel on the opposite end. I thought I had everything well organized through the arrangements I had made the previous day, but the process ended up taking several hours longer than I thought it would. The bottom line: When I got to my new hotel I found myself reassembling my diving and photographic gear as fast as I could to make one more dive that day.
I had stayed at this hotel before and I remembered a site on the house reef where I had seen some wonderful-looking blennies. They are very small fish, but they have such cute faces that it is impossible to pass them by. So I quickly removed the lens and port I had used for my morning dive, and I set up my camera system for some super-macro work. Moments later my buddy and I hurriedly headed for the dock and a short swim out to the house reef.
We had plans to meet some friends for dinner so if we were going to have time for a long dive, we needed to enter the water as soon as possible. We quickly got our weights and tanks, assembled our dive gear and headed down the dock. I jumped into the water, reached up and got my camera, and as soon as I put my camera housing into the water I saw a stream of bubbles coming from the interface where the lens port attaches to the housing. The camera system was only in the water for a matter of a few seconds, and the top of the housing just barely got submerged, but there was no doubt what was happening. My camera system was flooding. The housing was filling up with salt water, and that could easily end up costing me several thousand dollars.
Right and Wrong
As fast as I could I picked up the housing and tilted it downward so that any water inside would collect in the port instead of bathing the camera, lens or electrical connectors. My buddy was still on the dock so I handed my camera up to him and asked that he hold the system in the exact same position until I could get out of the water and take over.
To cut to the chase, I got lucky. Very lucky. I got a little bit of water in the housing, but none on my camera or lens. What I did right was to check my system for leaks as soon as I put it into the water. What I did wrong was everything else that led up to the flooded housing. I had allowed myself to get in a hurry when I changed the lens and port before my dive. I assembled my camera system in a room that wasn't well lit. Instead of relocating, I assumed I would assemble my housing properly, and that I would not have a problem. My thinking or, better stated, my lack of thinking was that I have assembled my camera system a zillion times. I am a pro. I know how to do it. I can take a shortcut. I've assembled my camera system thousands of times, including earlier that same morning, without experiencing a flood.
Sound familiar? I knew better, but I didn't do better. Clearly, I was complacent. I excused myself from practicing good fundamentals. Worse yet, I regularly teach underwater photography courses, and in every one of them I repeatedly emphasize the proper way to assemble camera systems and the importance of checking the assembly before making the dive. Heck, there's a bunch of reasons why camera systems might not work, but it usually comes down to user error and an improper assembly. I know that. I teach that. But I didn't do what I tell others to do, and the ocean couldn't care less if I am an instructor, divemaster or professional underwater photographer, or if I assembled my camera system properly earlier in the day. When it comes to taking camera systems into the water, it is all about what you do to set up and care for your camera system for this dive. The previous dive no longer matters.
Hopefully, I'll be smart enough to learn from my mistake, and I will also be less arrogant in the way I judge others for their actions. If I do, instead of judging others I'll analyze and learn. If you don't do things the right way, you might get lucky, but then again, you might not. And if you don't, or I don't, there can be quite a price to pay.
 Dive Training Quiz
1.The limestone skeletons of dead corals accumulate many tiny forms of marine life. For this reason it is called:
A. "Micro-rock"
B. "Live rock"
C. "The living dead"
D. "Rock on"
2. The genetic constitution of an
individual organism is referred to as its:
A. Phenotype
B. Genotype
C. Genesis
D. Organic chemistry
3.Women scuba divers are more
susceptible to hypothermia than their male counterparts.
A. True
B. False
4. A ring-shaped coral island surrounding a lagoon is known as an:
A. Anomaly
B. Out Island
C. Atoll
D. Isthmus
5. In the Maldives, flat-top coral reef formations that extend from the base of the atolls to very near the surface are called:
A. "Tikis"
B. "Tula"
C. "Tatupu"
D. "Tilas"
6. Dives in which a lot of physical exertion takes place can elevate a diver's carbon dioxide level. This is called:
A. Hypocapnia
B. Hypercapnia
C. Hypoglycemia
D. Hyperglycemia
7. A severe headache following a dive could be caused by:
A. Inhaling boat exhaust fumes
B. Hypercapnia
C. Dehydration
D. Jaw fatigue
E. All of the above
8. The whale shark is the world's largest whale.
A. True
B. False
9. Whale sharks capture their prey by:
A. Gulping large amounts of water
B. Ambushing it from underneath
C. Stunning it with sonar
D. Using bubble rings
10. Kelp fronds are buoyed by
balloonlike, air-filled bulbs called:
A. Pneumatocysts
B. Permabonds
C. Bladders
D. Bulbs
Answers: 1. B 2. B 3. B 4. C 5. D 6. B 7. E 8. B 9. A 10. A
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