Sharks of the St. Lawrence

//Sharks of the St. Lawrence
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    Greenland sharks return to the St. Lawrence river from the Arctic Circle each summer.

Having blogged about sharks in Canada going on 6 years now, I’ve noticed a few rumours that consistently pop up. The first is that a great white shark was caught in Ucluelet BC in 2005. That didn’t happen, and the second, that there are bull sharks in Lake Ontario or the Ottawa River, is nothing more than a case of bull sh(ark!). Bad pun, I know…

Yet there is actually some truth to the third rumour, that a great white shark could be in the St. Lawrence vicinity. Well, let’s modify that a little; the second largest great white shark ever measured was caught in the Gulf of St. Lawrence back in 1983, off Prince Edward Island.

No Bull Sharks in Canada (Or the Great Lakes)

Freshwater sharks like the bull shark live in lakes and rivers – but no bull shark has ever been found in Canada or the Great Lakes. The reason? It’s too cold. Photo Source:

You may have heard rumours over the past several years that bull sharks were well and multiplying in Lake Ontario. That’s false, pure and simple, despite what the National Post would have you believe in a satirical and, if you don’t mind me saying, irresponsible commentary from a national publication.

Bull sharks can indeed swim up rivers and live in lakes. We’ve seen this in several interesting situations, like sharks of Carbrook Golf Course in Australia. They’re fairly common in the southern United States as well, and have even been seen in the Mississippi River as far north as St. Louis.

But Bull Sharks don’t live in Canada, the St. Lawrence River, Ottawa River, Great Lakes and the many other places they’ve long been rumoured for several reasons, not the least being the same reason you wouldn’t jump in Lake Ontario on a frigid February morning: it’s too f***ing cold.

Bull sharks are a tropical species, and theoretically they could survive in the summer months in the Great White North, but as these biologists tell us, they can’t make it in the frigid winter temperatures we experience here in Canada. 

Theoretically, yes, they could survive a few months in summer, but the Canadian winter is a  beast of its own. Once the ice moved in, Mr. Bull Shark would be a popsicle, and that would be it.

A Great White Shark in the St. Lawrence Seaway?

This is doubtful. It’s true that great whites are making a comeback along the eastern seaboard and even stray into Maritime Waters. In fact, there’s even a minor hotspot for great white shark activity in Canadian waters at Sable Island, about 300 kilometres southeast of Halifax.

It’s also true that great whites have been seen in the Gulf of St. Lawrence. In fact, the second-largest great white shark ever measured was caught off Prince Edward Island in 1983 and made it to the esteemed ranks of ‘the world’s top 5 legendary sharks’ by Discovery Channel.

But great white sharks are oceanic creatures. There are no records of white sharks in the St. Lawrence seaway. It’s true they’ve been seen in estuaries, but it’s highly unusual for great whites to enter brackish water, and even less likely they’d travel so far inland away from their normal range.

The Greenland Shark 

Now that we’ve removed bull sharks and great whites from the equation, the St. Lawrence Seaway is actually quite rich in sharks. The greenland shark is the second-largest carnivorous shark on the planet – after Mr. Great White of course – that can weigh several tonnes and exceed 6 metres.

There are no bull sharks in the St Lawrence, Ottawa river or great lakes. However, greenland sharks come to the St Lawrence river each year. Relax, they don’t eat people. Photo Source: Wikimedia Commons

Greenland sharks are typically deep sea sharks, and spend most of their time in depths that can exceed 3,000 metres. Yet curiously, the mysterious beasts return from (presumably the Arctic Circle) to the St. Lawrence Seaway each summer – particularly around Baie-Comeau – with its much shallower water. It’s here that divers most often encounter this enigmatic sharks that feed, surprisingly, on seals and other creatures you’d think would require a speedy attack.

We’re still learning about greenland sharks and the role they play in Canada’s marine ecosystem.

The greenland shark is sensitive to sound. At this time, Greenland Shark Research (GEERG) does not recommend scuba diving with greenland sharks to reduce human risk posed to these fascinating creatures. That’s probably just as well for you, considering the challenges of diving in the St. Lawrence Seaway, but here’s a video of one such encounter.

**Update, March 4, 2018** In August 2017, a ‘Giant Shark‘ was recorded on video near Pasbebiac, Quebec, near the Gulf of St Lawrence. The catch? It was a Basking Shark – a harmless ‘Gentle Giant’ that feeds on plankton, and a welcome addition to the sharks that maintain the marine ecosystem of the St Lawrence area.

By | 2018-11-30T02:46:47+00:00 June 10th, 2016|Epic Canada|8 Comments

About the Author:

Steve Hutchings is an extreme sports blogger and adventure traveller with too much time on his hands. He loves shark diving and EDM/trance music. Also, he checks the stock market every 15 minutes.


  1. James July 28, 2017 at 2:29 am - Reply

    I found a website that says there are bull sharks in the st. Lawrence river

    • Steve Hutchings July 28, 2017 at 6:16 am - Reply

      Hi James,

      Both of those sites are satire (Lost Swimming and National Post, correct?). While there are greenland sharks in the St Lawrence, no bull sharks have ever been seen anywhere in Canada. It’s simply too cold for them.

    • JB August 28, 2018 at 3:38 am - Reply

      Their are Bull sharks in the st. Lawrence. I personally know a fish and wildlife worker. And there are nets setup in shallow parts of the river where they pull sharks from. The nets they’ll tell passer by’s that their to control a specific population of those Asian carp. But their actually there for sharks. 2 confirmed bull shark attacks in the great lakes in the last 2 years. One bull shark was 5’2″ . And the other 5′ roughly. Also 2 baby’s were pulled out and are now at the Minnesota aquarium!!!

    • John August 28, 2018 at 3:40 am - Reply

      I also watched a documentary that I wish I had recorded on Bull sharks entering through the St.Lawrence. I’ve tried for years to find it. Also they showed the nets and their purpose.

  2. Justin August 20, 2017 at 2:54 pm - Reply

    Jeremy Wade caught one on River Monsters in St. Lawrence River. Check it.

  3. JASON LOXTON December 3, 2017 at 6:46 am - Reply

    James would be correct on bull sharks although I am not 100% on the location.

    One thing I do know it was on one of his shows that he caught a bull shark in a great lake I believe it was lake Michigan.

    There have also been other scientific documentary shows that show bull sharks have been migrating to the great lakes as the waters are getting warmer.

    Also the ministry of fish and game of Ontario confirmed a bull shark was caught in the St Lawrewnce.
    But specifically remember a great lake being mentioned by Jeremy Wayde in one of his episodes of bull sharks.

    I also remember scientist’s tracked a tagged bull shark to a great lake.

  4. Drake March 18, 2019 at 9:03 pm - Reply

    I have been studying this phenomena world wide for over five decades and there is proof of over 80 species of sharks listed that have or do appear from time to time in freshwater and scientist actually out right lie about this phenomena do to they do not like the calls and do not want public panic. The fact is that populations of everything from dog fish to mammal species and whales to seals all do this behavior and many sharks can survive long periods of time in freshwater. A sand tiger shark even jaw was found fresh in the Ohio river. Films and even old newspaper reports of attacks from lake erie as well many species of sharks from blue nose to even a great white filmed hundred miles up river. Thames river often gets giant congor eel to sharks of various species that have been caught or found dead from time to time over the centuries and always they make claim even in 1800s newspapers that some how some one must of let them loose in the lake sort of idea.
    The reality is that most species of sharks likely can tolerate or even thrive over time in freshwater. However most do not bother but when chasing schools etc they get sidetracked up rivers and keep going. I am astonished world wide the lack of knowledge on this subject and people listening to ichthyology theories when no one really has done these studies and the few ever done with specimens already weak from being trapped etc might have dies easier. proof of even some Connecticut rivers and Delaware with even basking sharks living in a creek for weeks and only died because some idiots shot it. Hundreds saw the creature swimming around as happy as can be and was over thirty feet long. Read my upcoming book on this and many other interesting research that challenges these silly opinions by people whom never have done experiments on these species and cannot know if they can acclimate over time some of them to it.

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