Scotian Shelf

• In the vast St. Lawrence River, an impressive variety of animals live on the seabed.
• These organisms live either buried in the sediment (infaunas) or on the surface of the seabed (epibenthos).
• As far back as 1988 researchers listed over 1,855 species of benthic invertebrates living in the estuary and gulf of the St. Lawrence River.

Luminous worms

• Some of these worms are actually capable of bioluminescence.
• The production of light in the form of luminous flashes has three general functions: defensive (to escape predators), offensive (in support of predation) and communicative (for reproduction).
• In the St. Lawrence River, the only scale worms with this ability are of the Harmothoe genus, of which there are five species.

Are corals cold?

• But does coral only grow in warm waters?
• Corals are actually marine polyps, cylindrical animals with a mouth surrounded by a ring of tentacles, that secrete a molecule called calcium carbonate to form a skeleton.
• There are two types: soft corals, with an internal skeleton that reinforces the structure of the colony (a collection of cloned individuals) while ensuring its elasticity, and hard corals, where each polyp secretes a cup-shaped external skeleton, creating their characteristic rigidity.

Starfish: dreaded gourmets

• They are actually fearsome predators, and understanding how they feed will likely change the way you see them.
• Faced with the two greediest species in the St. Lawrence (Asterias rubens and Leptasterias polaris), mussels normally have nothing to fear.
• But thanks to dozens of ambulacral feet — little suckers on their underside — starfish can easily open mussels.

You said centenarian?

Present in the Gulf of St. Lawrence, particularly in the Magdalen Islands, the Northern quahog (Arctica islandica) is the world’s longest-living animal. It is a bivalve mollusc protected by a calcareous shell with two valves, like that of a mussel or oyster. The Northern quahog can easily live up to 200 years, but the oldest specimen, recorded in Iceland, was 507 years old.
Other bivalves are known to live long lives. The age of these molluscs can be determined by the growth rings on their shells, rather like trees, but the technique here is called sclerochronology. It is even possible to read the history of the climate on the shells of several bivalves and use this information to predict future conditions.

Worms, medicine and the Olympics

• Although this worm could revolutionize medicine, it could also pose problems for anti-doping agencies and athletes.
• Virtually undetectable and hyper-performing, the incredible oxygenating benefits of the arenicolous worm’s hemoglobin could undoubtedly boost athletes’ performance at the next Olympics.

Natural “crazy glue”

• Although mussels are tossed about by breaking waves all day long, they still manage to hold tight to the rocks.
• The byssus, a collection of hair-sized fibres that are both strong and elastic.
• The proteins that make up byssus form natural ‘crazy glue’; this liquid glue hardens rapidly, enabling the mussel to adhere with unrivalled tenacity to virtually any surface, even wet ones.

• Cindy Grant is a member of the Québec-Océan strategic group and of the Unité Mixte Internationale Takuvik.
• Lisa Treau De Coeli is a member of the Québec-Océan strategic group and of the Unité Mixte Internationale Takuvik.