Listening to what's happening underwater: why we use a hydrophone
There's much more going on on the St. Lawrence than we can see... What if we could hear it too?
At Du Fleuve , we have decided to integrate a hydrophone into several of our cruises to add a whole new dimension to the observation of the marine ecosystem: the sound world of the St. Lawrence River . This instrument captures underwater sounds and reveals an often unsuspected richness. 
By submerging the microphone underwater, you can sometimes hear the songs of humpback whales . Although humpback whales mostly sing in warmer waters, you can sometimes hear their vocalizations here, during a lucky encounter. Beluga whales , on the other hand, are well known for being particularly talkative – it's not for nothing that they are nicknamed the canaries of the sea ! Thanks to the hydrophone, their exchanges often become audible, and we become aware of the incredible complexity of their communication.
But listening underwater also raises awareness and awareness of another phenomenon: noise pollution . The oceans and the river are not as quiet as we might think. Between engine noise and human activity, sounds that travel through the water can disturb marine mammals, making it harder for them to navigate and communicate. By making these sounds heard by our passengers, we hope to raise awareness of this crucial issue and the importance of minimizing our impact on marine life .
Photo @Renaud Pintiaux.
We also chose this tool because the Saguenay St. Lawrence Marine Park is a protected area with many rules to preserve its wildlife. Belugas are an endangered species, and the approach of boats is strictly regulated . Even if we cannot observe them up close, the sound travels long distances . The hydrophone therefore allows us to listen to these animals without ever disturbing them, reminding us that a respectful presence can also be an attentive presence.
Listening to the river, as well as observing it, is an ultra-special experience. It connects us even more to our environment and the nature we are lucky enough to encounter. The next time you embark with us, take a moment, close your eyes, and let yourself be carried away by the sounds of the river. 
For more information about our cruises, click here .
