Watching a humpback whale surface is an unforgettable experience. The size, power, and presence of these animals create a moment that is difficult to describe. But what happens below the surface reveals another part of the story. One that cannot be experienced through sight alone.
During a recent kayak outing with a hydrophone, we had the opportunity to record humpback whales both visually and acoustically. We experienced one of those encounters that reminds us why listening to the ocean is just as important as watching it.
As we drifted quietly on the water, the hydrophone captured the underwater soundscape below the kayak. A humpback whale was observed spy hopping nearby, a behavior in which the whale rises vertically in the water, bringing its head and eyes above the surface. Shortly afterward, a group of three to four humpback whales approached and passed beneath the kayak, allowing the hydrophone to record their vocalizations at close range.
The recordings revealed powerful low-frequency calls, pulsed sounds, and tonal components with remarkable clarity. Hearing these underwater sounds in real time added an entirely new dimension to the encounter and a deeper appreciation for the complexity of humpback whale vocalization.
Audio of CRT-90P hydrophone with video, humpback whales swimming under kayak, Maui 2025
Whale watching from the surface provides only one view of what is happening in the ocean. There is an entire acoustic world beneath the waves that remains hidden from our eyes. While waiting for a whale to appear at the surface, a hydrophone allows us to experience the sounds that are continuously present underwater; vocalizations, movement, and the many layers of natural ocean noise that surround marine life.
This is what makes listening with a hydrophone such a unique addition to whale watching. Seeing a whale breach, surface, or travel through the water is remarkable, but hearing the sounds beneath the surface adds another level of understanding and appreciation.
Kayaks provide an excellent platform for this type of experience because they allow for quiet observation with minimal disturbance. Without the engine noise and vibration associated with larger vessels, it is possible to hear the natural sounds of the ocean more clearly. A calm kayak drifting on the water creates an opportunity to observe and record marine life while maintaining a respectful distance.
Responsible wildlife observation is central to our approach. We believe in experiencing whales without interfering with their natural behavior. We do not swim with whales or attempt to enter their environment. Instead, we focus on responsible observation, using tools like hydrophones to learn more while allowing these animals to continue their natural activities.
The ocean has a story to tell beyond what we can see. A hydrophone helps us listen.
