Saturday, March 29, 2008

New Brunswick is also home to Great White sharks

One of the very interesting under-water communities under Mother Nature's watch "in New Brunswick" is the shark community. We in New Brunswick often tend to think sharks are fish that are found "down south" or "somewhere else". However, that's not the case. We have sharks off our New Brunswick coastline and they play a very significant role as a member of the underwater community. Let's pay a call on the shark community off New Brunswick today to see who's here and how they're doing.

The shark community took a major PR hit 32 years ago with the release of the movie Jaws. That label that sharks are human-munching machines is extremely unfortunate. There are approximately 400 shark species worldwide. Of those, there are very few species that would ever consider attacking a human. In fact, the vast majority of them feed on fish and marine mammals and the huge second-largest shark in the world, the Basking Shark, comes to our Bay of Fundy water each summer to feed on the huge quantities of the tiny sea creatures copepods and krill. The world's largest shark, the Whale Shark, has been confirmed in one sighting and suspected in another in the Bay of Fundy.

Unfortunately, knowledge of the life and times of the shark community off our coastline is very much in its infancy. Dr. Stephen Turnbull and his small team at UNBSJ in Saint John have devoted considerable time and research effort to get a handle on the status of sharks in our waters and much of the present knowledge we have is a result of his efforts. The freshly minted Canadian Shark Conservation Society and its associated website is a product of his efforts to alert the public to the pressing need to conserve and protect the shark community. It is now known that 98 per cent of the world's shark species are in population decline as a direct result of human over fishing.

So just what shark species do we have as more common natives of the area? Many felt in the past that our cool waters were not suitable for the shark community however, for some species, that may be exactly what they choose. The Porbeagle Shark is thought to be the most common shark in the North Atlantic Ocean. The Blue Shark is considered the most common pelagic (deeper sea) shark and the most common shark anywhere is likely the smaller Spiny Dogfish Shark. The average Porbeagle Shark caught in the Bay of Fundy would be 2.3 m in length and weigh in at 165 lbs, however they have been recorded elsewhere at lengths of all most 4 m and in excess of 500 lbs. We may not be seeing the larger adult ones as many are being decimated by over fishing before they reach adult size.

If too many sharks are removed from the population, recovery rate is very slow as it may take up to eight to 13 years for male and female respectively for sharks to reach sexual maturity and they may be only capable of producing at best a few young "pups" per year. This makes recovery painfully slow.

The Porbeagle Shark, Mako Shark, Thresher Shark, Basking Shark, and Spiny Dogfish Shark may be the more common sharks off New Brunswick, however 15 different species have been recorded as being in the area, some only a few instances like the Great White Shark and the Whale Shark (largest known shark of the world). It can be very difficult to assess the numbers present as most species, with the exception of the huge Basking Shark, don't come to the surface to feed so go undetected as we simply don't see them. It's just not like whales that are mammals and have to come to the surface to breathe where we can readily spot them.

The Thresher Shark (very long whip-like tailfin) is definitely present on occasion as well and this species sometimes happens to be spotted leaping out of the water for onlookers that are "in the right place at the right time." The Porbeagle Shark will occasionally leap too, but not as readily as the Thresher Shark. The huge Basking Shark will sometimes leap (breach) just as a whale, which is a value-added bonus to whale watching expeditions.

There seem to be some misconceptions about shark meat as an edible product. Shark fin soup is a very sought-after delicacy among certain cultures in parts of Asia. The flesh is removed from the fin to get the noodle like cartilage strands. The shark fin can sell for $1400/lb and a bowl of shark fin soup would sell at $70-$200 a bowl, depending on where you are.

In Canada, it is illegal to have shark fins on board a vessel without the corresponding shark. This has stopped the very unethical practice of catching the shark, cutting off the fins, and discarding the remainder of the shark. Shark meat does not command a worthwhile price. There is no legal shark fishery off the New Brunswick Coast, however there is an active fishery off Nova Scotia. The shark is an animal that retains high urea levels in its flesh as a way to live in seawater.

This creates an offensive odour in the flesh that has to be removed by leeching it out before going to market.

The Porbeagle Shark has some of the most desirable qualities as an edible fish meat; however similar Mako Shark is often mistakenly marketed as Porbeagle Shark. The common Spiny Dogfish Shark finds a market in Europe and in some places in North America where it gets marketed as Grey Fish or Rock Salmon to be used in preparing fish and chips.

The swordfish fishery more than occasionally catches sharks and unfortunately that may end up being marketed as swordfish meat.

However, there is yet another consideration to be aware of in the consumption of shark meat. Sharks, being among the top of the food chain, may have bioaccumulate toxic mercury (Hg) in their flesh. The potential toxic levels of mercury in shark meat for human consumption is a public health concern. Ironically, shark fin soup is considered an aphrodisiac in the Orient. (Elevated levels of mercury can actually cause impotence!)

Catch and release shark fishing is legal in New Brunswick. If done properly, this allows for more information to be gathered for research purposes, and encourages a sustainable tourist industry. A group called Sharks Unlimited has set up, operating out of Alma, New Brunswick, to make catch and release shark fishing trips.

This group has received high praise from Stephen Turnbull and other shark conservation groups for their conservation methods to provide more shark data off our coast, create a tourist industry, and increase the awareness of the plight of the sharks.

Naturescope plans to pay an on-the-spot visit to Sharks Unlimited late this summer for an up-to-the-moment account of the action.


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