SHARK WEEK: 14 sharks, including the Great White, swim in B.C. waters and more are coming

  This article was written by Kami

For most Vancouverites, despite our ocean setting, Jaws is about as close as we’ve ever been to a shark — and it was mechanical.

 

We’ve spotted seals near the docks at Granville Island, and whales and dolphins while sailing on B.C. Ferries, but sharks — big ones, anyway — are something you only see while diving in the tropics, right?

Wrong.

The Department of Fisheries and Oceans Canada has documented 14 species of sharks — from the tiny two-foot brown cat shark to the mammoth, but harmless, 33-foot plankton-eating basking shark — lurking in the coastal waters of British Columbia.

Also included in the list of 14 B.C. sharks is — gasp — the great white shark. The 19-foot monster with its triangle-shaped serrated teeth does indeed venture into B.C. waters, but the DFO admits it’s a rare occurrence when the big fish makes its way up here from the warmer California waters. The National Marine Fisheries Service estimates there is a growing population of about 3,000 white sharks in the eastern North Pacific.


William Cheung, associate professor at the Institute for the Oceans and Fisheries at UBC, says with oceans warming due to climate change we can expect more tropical sharks like the great white to visit northern waters in the coming few decades.

“Based on my team’s computer simulation modelling, we found that climate change will cause an expansion of the range of great white shark to northern temperature areas, including the offshore waters of the northeast Pacific, which includes B.C.,” Cheung said. “If you look at the coast of California, it is expected that the types of species we see there could be in B.C. waters if we maintain at the status quo and do not mitigate carbon emissions. Species in California include the oceanic whitetip shark, and the great white shark. In the Atlantic, we would expect to see great whites along the coast of Newfoundland. Currently, they have been recorded, but sightings are rare.”

That’s not to say we don’t have any big predator sharks who are permanent residents. Salmon sharks, stout 10-footers with sharp “awl-like” teeth, are very common around these parts.

While they feed on salmon and other bony fish, there has been at least one reported — but widely discounted — attack on a human.


In 2012, Campbell River’s Kaitlin Dakers was surfing off Tofino when she suffered severe cuts to two of her fingers. She said a doctor at the Tofino hospital and the surgeon in Campbell River who patched her up both said the cuts were from a very sharp, very quick bite.

A salmon shark was blamed. However, Nick Dulvy, a professor at SFU who specializes in studying sharks and is the current Canada Research Chair in Marine Biodiversity and Conservation, doubted it.

“The reality is that this shark has never been implicated in an attack on a human being, and there’s never, ever been a shark attack in Canada,”Dulvy told the Vancouver Sun at the time. “There are way more (people) killed by strikes of lightning in North America each year, and there are way more people killed by falling television sets each year than they are killed by shark attacks.”

Dulvy said it was more likely that Dakers was bitten by a seal, while veteran surfers claimed the injury could have been caused by her finger getting caught in her board’s leash.

Other common sharks in B.C. waters include the brown cat shark, blue shark (10 feet), Pacific sleeper shark (14 feet), sixgill shark (16 feet), spiny dogfish (five feet), and tope (soupfin) shark (6.5 feet).

Sharks listed as rare, or infrequent to B.C. waters, include the great white, sevengill shark (10 feet), bigeye thresher (14 feet), shortfin mako shark (13 feet), greeneye shark (1.5 feet) and the extremely rare basking shark.


The endangered basking shark, the biggest and rarest fish on Canada’s west coast and second largest fish in the world behind the whale shark, was photographed in 2013 by marine researcher Wendy Szaniszlo on the Canadian Coast Guard’s 58-metre research ship W.E. Ricker off Brooks Peninsula on the west coast of Vancouver Island.

The gentle giant was nearly wiped out in an act of shark genocide by the federal government.

“Half a century ago Ottawa fitted sharp blades to the bows of its vessels to deliberately kill as many basking sharks as possible for interfering with commercial fishing nets on the B.C. coast,” Vancouver Sunreporter Larry Pynn wrote in 2013.

Once there were as many 3,000 to 5,000 basking sharks in B.C., but thanks to a liver oil fishery (1941-1947) and the federal eradication program (1945-1970), the number has dropped to “only a few,” according to the DFO.

“There were a total of eight reported sightings of basking sharks on the B.C. coast from April to September this year, mostly off the west coast of Vancouver Island but also as far north as Haida Gwaii. In addition to the one confirmed, two sightings were considered reliable,” Pynn wrote.

A 25-foot basking shark was spotted in Puget Sound near Seattle in 2014.

Sharks found in B.C. waters (from Department of Fisheries and Oceans Canada):

SALMON SHARK
Lamna ditropis
• Pelagic (surface to 375 m)
• Length to 3 m (10 feet)
• Short, heavy body; short snout
• Black or dark grey on the top; abrupt change to white blotches below
• Two horizontal keels just prior to tail fin
• Awl-like teeth with small sharp denticles on each shoulder of the main point.



BROWN CAT SHARK
Apristurus brunneus
• Pelagic and demersal (33-950 m)
• Length to 68 cm (2.2 feet)
• Light or medium brown
• Dark margins on fins
• First dorsal fin has posterior position over pelvic fin
• Two dorsal fins of equal size



BLUE SHARK
Prionace glauca
• Surface waters
• Length to 3 m (10 feet)
• Dark indigo blue on back shading through clear bright blue on sides to white below
• Notable for the long sabre-like pectoral fin
• Well developed snout; slender body form




SPINY DOGFISH
Squalus acanthias
• Pelagic and demersal (surface to 1460 m)
• Length to 1.6 m (5 feet)
• Slate grey to brown on top, white to light grey below
• Two dorsal fins with spine in front of each
• No anal fin




PACIFIC SLEEPER SHARK
Somniosus pacificus
• Midwater and demersal (surface to 245 m)
• Length to 4.3 m (14 feet)
• Blackish brown all over or slate green with darker streak-like mottling
• Short caudal peduncle (narrow part of a fish’s body to which the caudal or tail fin is attached)




TOPE (SOUPFIN) SHARK
Galeorhinus galeus
• Pelagic and demersal (surface to 471 m)
• Length to 2 m (6.5 feet)
• Dusky grey on top, paler to white on sides
• Second dorsal fin directly above anal fin
• Black markings on juvenile fins
• Slender body, long-snout
• No keel on caudal peduncle




SHORTFIN MAKO SHARK
Isurus oxyrinchus
• Pelagic (surface to 740 m)
• Length to 4 m (13 feet)
• Large black eyes, a sharp snout, large, narrow, hooked teeth with smooth edges
• Dark blue on top, white below; underside of snout and jaw is white
• Tiny second dorsal and anal fins




SEVENGILL SHARK
Notorynchus cepedianus
• Demersal (135 m to 570 m)
• Length to 3 m (10 feet)
• Sandy grey to reddish brown, with scattered round black spots
• Seven gill slits on each side
• In upper jaw most teeth have one dominating cusp curved inward. Teeth in lower jaw have a series of cusps.




COMMON THRESHER SHARK
Alopias vulpinus
• Pelagic (surface to 366 m)
• Length to 5.8 m (19 feet)
• Upper caudal fin more than half the length of the shark
• Brown colouration
• Eyes moderately large




BIGEYE THRESHER
Alopias superciliosus
• Pelagic (surface to depths of 65 m, occasionally to 500 m)
• Length to 4.3 m (14 feet)
• Brownish on top, creamy white below
• Upper caudal fin nearly as long as rest of shark, notched or helmeted contour of head
• Huge eyes extending onto dorsal surface of head




SIXGILL SHARK
Hexanchus griseus
• Demersal (to 2307 m)
• Length to 4.8 m (16 feet)
• Dark brown or grey on top, nearly black in some specimens, somewhat paler below
• Six gill slits on each side, all long
• Two rows of teeth, moderate-sized in upper jaw, larger in lower jaw




GREEN EYE SHARK
Etmopterus villosus
• Demersal (406 to 911 m)
• Length to 46 cm (1.5 feet)
• Dark brown or blackish body, underside is darker; black mark above pelvic fins
• Short tail; short fins; spine prior to each dorsal fin
• No anal fin
• Large green eyes




BASKING SHARK
Cetorhinus maximus
• Surface waters
• Length to 10 m (33 feet)
• Greyish brown to slate grey to black; can fade to white below
• Very long gill slits, which almost encompass head
• Combs of horny gill rakers
• Small numerous teeth
• Strong horizontal keel just prior to tail fin




GREAT WHITE SHARK
Carcharodon carcharias
• Pelagic (surface to depths of 1280 m)
• Length to 6 m (19 feet)
• Slate brown or grey to almost black on top, shading to dirty white below
• Crescent-shaped tail fin
• Triangular serrated teeth


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