Home Dive Almanac Diving Almanac: Celebrating the Underwater World – SEPTEMBER 2018

Diving Almanac: Celebrating the Underwater World – SEPTEMBER 2018

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This issue’s selection covers places and creatures from the feature stories in Scuba & H20 Adventures Magazine, including sharks, British Columbia, as well as some recent record news.

Possibly the world’s largest Great White Shark

In August 2015, biologist Mauricio Hoyos Padilla described what may be the largest white shark ever filmed. Based on the size of his boat and observation cage, Dr. Hoyos estimated the size of the shark at 6 m (20 ft). The female shark known as DeepBlue was also filmed by videographer Michael Maier (Germany) in 2013 off the island of Guadaloupe, Mexico. The record-sized shark is estimated to be around 50 years old and it may have been gravid (pregnant) at the time of Maier’s encounter.

the most abundant sharks in the world

Atlantic and Pacific spiny dogfishes (Squalus acanthias and Squalus suckleyi) are the most abundant sharks in the world. These small shark species (the larger femalemeasures slightly more than 1.2 m / 4 ft) congregate in large schools of hundreds or thousands of individuals, much to the delight of divers in Canada and the United States. Total population was once measured in the billions, but overall numbers have been severely reduced due to commercial fishing (targeted and by-catch) over the last century. The spiny dogfish (combined populations of Atlantic and Pacific) is none the less still believed to be the most abundant shark in the world, with frequent observations by divers in British Columbia and the Eastern Seaboard of North America. The Atlantic spiny dogfish was declared overfished in theU.S. in 1998 and its numbers have been depleted by over 95% in Europe where it is sold in fish and chip shops under the names rock salmon and huss. The spiny dogfish is also harvested for its liver oil, vitamins, leather, sand paper, dog food, fertilizer and biological dissection and research.

The spiny dogfish is also known as grayfish, picked dog fish, spiked dogfish, spring dogfish, and spur dog. Although very inquisitive and fearless when encountered, it poses no threat to divers and it is a thrill to observe alive and well underwater.

The world’s fastest localized current

Speaking of thrills, this should excite fans of drift diving. The world’s fastest localized current, which was clocked at 16.1 knots (29.6 km/h / 18.4 mph), is found at the Sechelt Rapids (Skookumchuck Narrows), in British Columbia. It is estimated that for a 3.6 m (12 ft) tide, 757 billion litres (200 billion gallons) of seawater flow through the “Skook” in six hours. Several charter operators offer dives at the site during slacktide. Divers are attracted to the site for its abundance of marine life, especially the sessile invertebrates that cling to the rocks to catch passing plankton on the fly in the ripping current. Diving the Sechelt Rapids during tidal movements when the current is at high velocity is obviously not recommended as it would be extremely dangerous. Usual drift dives in the Skookumchuck Narrows thus do not attain speeds anywhere near 16.1 knots.

world’s oldest diver

In recent news, Ray Woolley (United Kingdom) bested his record for the world’s oldest diver when he celebrated his 95th birthday on the wreck of the Zenobia in Lanarca, Cyprus, on September 1, 2018. The dive lasted 44 minutes with a maximum depth of 40 m (131 ft). Ray Woolley joined Portland & Weymouth BSAC in 1960 before being posted to Cyprusby the Foreign Office in 1964 wherehe joined BSAC 107S and became a diving instructor. Erwin Paul Staller (USA), 93, made a 36-minute dive with a maximum depth of 16 m (52 ft) at Grace Bay, Turks & Caicos, on October 24, 2014. And in his own words, Stan Waterman hung up hisfins on April 5, 2013, at age 90.

Read the full stories and discover hundreds more diving records, outstanding diving personalities, and 6,000 years of diving history in the Diving Almanac! www.divingalmanac.com

About Jeffrey Gallant

Jeffrey Gallant

Jeffrey Gallant is the Editor of the Diving Almanac and a shark researcher. He started diving at age14 in 1982 and has since led scientificand training expeditions around the world. Among other accomplishments, Gallant was trained as an aquanaut in Romania in 1995 and he dove with Équipe Cousteau in 1999.