With the Belugas: Week of September 25

  • Deux bélugas sans grande marque apparentes. Un beau défi pour la photo-identification! © GREMM
    06 / 10 / 2017 Par Équipe du Bleuvet

    Hunters on the Prowl!

    A few weeks ago, we observed a beluga whale spitting on the water surface to hunt herring. This week we witnessed our white whales in the midst of yet another hunting foray.

    In the fall, we often see large gatherings of belugas between Buoys S7-S8 and Pointe Rouge that move as if there were a treadmill carrying them under water to Pointe Rouge, while at the surface they actively swim toward the buoys of the Saguenay.

    On one late afternoon outing, we find ourselves amongst one of these herds that make our heads spin. There is no rhyme or reason to the animals’ movement pattern and we struggle to properly position ourselves for photo-ID work. Patience is a must!

    Fishes that appear to be striped bass trying to escape the belugas. © GREMM

    The group we are targeting completes its sequence of breathing and diving, but we can still make out their silhouettes just below the surface of the water. We can see that they are swimming very fast and constantly changing direction. Suddenly, we spot a small mass of water that quivers and moves. Something is happening just below the surface! Our belugas are behind this activity, but indirectly: it’s fish that are wriggling down there! We move closer for a better view. Michel arrives to snap a few photos of the scene that has just unfolded before our eyes. The show lasted for just a minute before the water surface returned to normal.

    Back on land, we carefully examine the photos on the computer screen. Hard to say for sure, but one photograph in particular gives us good reason to suspect that these were striped bass. In one of the shots, we can even make out the silhouettes of four of these fish.

    Last year, for the first time in his long career, Michel witnessed a scene of striped bass being hunted. With the return of this species to St. Lawrence waters, it is possible that striped bass are being consumed by belugas, which have a rather diverse diet.


    Property of the GREMM and the St. Lawrence National Institute of Ecotoxicology, the Bleuvet is a research boat dedicated to the research program on St. Lawrence belugas. Managed by GREMM scientific director Robert Michaud, the Bleuvet crew is composed of Michel Moisan and Tim Perrero.