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Howe Sound

Brandon Cole

Q1 2021

With nearly 16,000 miles of rugged coastline and more than 40,000 islands and islets, British Columbia’s Howe Sound features fantastic marine life and spectacular coldwater scuba adventures. Stretching 27 miles from its narrow head under lofty mountain peaks at Squamish to its wide-mouth opening into the Strait of Georgia just northwest of Vancouver, Howe Sound is North America’s southernmost fjord. This sea-to-sky corridor crafted by glaciers and perfected by time seems tailor-made for subsea exploration — reef and wreck, rec and tech.

Smile, Crocodile

Jennifer Hayes

Q1 2021

Crocodiles are apex predators, and in the wrong place and time, humans are potential prey. There are exceptions, but most of these wonderful and primitive reptiles won’t squander encountering a potential meal. When swimming in any reptile habitat, know who and what you may encounter, or don’t swim at all. The resident American crocodiles at Jardines de la Reina routinely share their waters with snorkelers and divers, but Jen Hayes didn’t feel the same comfort working in Nile crocodile waters in Botswana.

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Cylinder Safety

Francois Burman, Pr. Eng., M.Sc., and Mark Gresham

Q1 2021

Users must operate cylinders within design parameters, such as filling only to the rated service pressure and having cylinders inspected by formally trained and qualified technicians and requalified by a reputable, recognized test facility. More than 90 percent of ruptures occur during filling, so diligent inspection during this process is critical. Cylinders should operate safely throughout their entire service lives if users adhere to design and operating conditions.

Undercover Crabs

Ned and Anna DeLoach

Q1 2021

Most decorator crabs belong to one of eight families in the superfamily Majoidea, commonly referred to as spider crabs. About 75 percent of the group’s more than 1,100 global species mask their presence by wearing disguises made from living organisms scissored from the landscape. They commonly hijack seaweeds, sponges, tunicates, bryozoans and hydroids. The crabs manipulate the purloined pieces of attire with their mouths before attaching them to one of the many fishhook-shaped bristles arranged in rows on the carapace, rostrum, walking legs and claw arms, depending on the species.

Children and Diving

Q3/Q4 2020

Opinions vary among dive medicine experts about how to mitigate the complex issues around children and diving, such as age requirements, training levels and limitations. Children are still developing both physically and mentally, which affects the decision about whether a young diver is fully capable or requires some modification. Concerns about decompression sickness, out-of-air emergencies and gas toxicities that occur at greater depths affect depth-limitation guidelines, which vary among the training agencies.

Step Exercises with Cardio

Jessica Adams, Ph.D.

Q3/Q4 2020

Considered a form of preventative medicine by the American College of Sports Medicine, exercise has a wide range of positive physical, mental and cognitive benefits. This program should help keep you fit and healthy for your next dive. Use the modifications and challenges to suit your individual needs and fitness level. This timed program is designed to keep your heart rate elevated throughout the routine to strengthen your heart, lungs and muscles.

Ocean Views 2020: Glory Days

Q3/Q4 2020

As this year’s Ocean Views photo contest celebrates the 10th anniversary of the collaboration between Alert Diver and the Nature’s Best Photography magazines for the 2020 Nature’s Best Photography International Awards, the collection of entries is replete with speedballs of significance. The quality of the photography is the best we’ve judged yet and coincidentally the most eclectic in subject and location. Viewed in aggregate, the 31,000 images and videos submitted by 2,000 entrants from 67 countries cover a range of destinations including polar, Caribbean, Indo-Pacific and even freshwater habitats.

Oil and Particulates

Francois Burman, Pr.Eng., M.Sc.

Q3/Q4 2020

Research has described the effects on human health of elevated partial pressures of carbon monoxide (CO) and carbon dioxide (CO2) while diving, but only occupational health and safety studies have covered solids such as oil mist and particulate matter suspended in air and only in terms of breathing at the surface.

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