Creature Feature – St. Lawrence Sharks

The St. Lawrence River is home to LOTS of fish. In the river’s International section alone, there are 85 species, including popular sportfish such as striped, large- and smallmouth bass, walleye, northern pike and muskellunge.  Prehistoric lake sturgeon swim the waterway, along with rare fish species like the pugnose shiner.  There are also at least 8 species of sharks known to frequent the St. Lawrence.  These sharks are not new or unusual visitors to the gulf and estuary sections of the river.  In fact, they have likely been swimming there since the end of the last ice age, around 10,000 years ago!

• Basking shark – common in the gulf and estuary; June to September.
• White shark – common in the gulf, but rare to the estuary; July to October. 
• Greenland shark [illustration] – year-round resident, common in both the gulf and estuary.
• Common thresher – very rare inhabitant of the gulf portion only; July and September. 
• Blue shark – common in the gulf, but rarely found in the estuary; July to September.
• Porbeagle shark – common in both the gulf and estuary; June to October.
• Spiny dogfish – common to the gulf, but rare visitor to the estuary; July to September.
• Black dogfish – year-round resident, common in both the gulf and estuary.

Human activity has dramatically impacted St. Lawrence shark populations, with some species reaching historic lows; yet more sharks are being reported there each year.  Why?  The St. Lawrence Shark Observatory (ORS) warns that “appearances can be deceiving” and points to the present age of smartphones when shark catches are shared with the touch of button.  Despite the increase in observations, most sharks are in decline due to overfishing and by-catches.

Article by Margie Manthey
Illustration by St. Lawrence Shark Observatory