As humans, we often take communication for granted. We use words, gestures, and facial expressions to convey messages to each other. However, animals have their own unique ways of communicating, and one species in particular – the trumpeter swan – has recently revealed a whole new world of communication to researchers.

Trumpeter swans are North America’s largest waterfowl, and they are known for their striking appearance and hauntingly beautiful calls. But their communication goes far beyond what we can hear with our own ears. It turns out that these birds can communicate through vibrations in the water, using a complex system of signals to convey everything from warnings to courtship displays.

Scientists first began to explore this hidden world of swan communication back in 2016, when a team at the University of Montana set out to study the birds’ vocalizations. They found that while some of the calls were easy to hear, others were too quiet for human ears to pick up. But when they used underwater microphones to listen in, they discovered a whole new dimension to the swans’ communication.

By analyzing the patterns of vibrations in the water, the researchers were able to identify dozens of different calls that the birds use to communicate with each other. These include warnings about predators, invitations to mate, and even individual vocalizations that seem to serve as a sort of name or identifier for each bird.

But the researchers didn’t stop there. They also wanted to know how the swans were able to pick up on these subtle vibrations and interpret them correctly. To answer this question, they turned to a tool called a hydrophone – essentially a microphone that is specially designed to pick up underwater sounds.

Using hydrophones, the researchers discovered that swans have some pretty impressive ears – or, rather, ears that are adapted to hearing vibrations in the water. When a swan hears a vibration in the water, its ear bones transmit the sound to its inner ear, where the brain can interpret it as a specific call or signal.

So not only are swans communicating in a way that is invisible to our eyes and ears, but they are also able to pick up on nuances and subtleties that we would never be able to detect on our own.

All of this research is helping us to better understand the behavior and communication of these fascinating birds. But it’s also a reminder that the natural world is full of hidden wonders – and that by listening closely and looking carefully, we can discover new things about the creatures that surround us. Who knows what other secrets are waiting to be uncovered?