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Science Section

By Dr. Beth Brady, Senior Conservation Associate

Did you know that manatees vocalize? Manatees have excellent hearing, so it makes sense that vocalizations are important to them. All species of manatees produce vocalizations. In many areas of the world, it is difficult to study manatees, as they can be hard to find and are wary of humans. Analyzing the sounds they produce can provide valuable insights into factors such as use of habitat, the presence of adults or calves, and the number of individuals. Manatees have vocal folds in their throats that allow them to produce vocalizations during various behaviors such as playing, resting, feeding, and when they are scared. Communication is particularly important between mothers and their calves. Moms and calves use vocalizations to stay in contact, and a mom can recognize her calf’s calls from the calls of other manatees. Manatee calls can be heard by humans, but they occasionally reach ultrasonic frequencies. Scientists believe that these ultrasonic frequencies may assist mothers in locating their calves when they are separated.

Manatees produce five distinct types of vocalizations: squeaks, squeals, high squeaks, chirps, and squeak-squeals. The most prevalent among these are squeaks, high squeaks, and squeals, with squeaks being the dominant vocalization, especially in adult calls. High squeaks are commonly produced by young calves. As calves age, the high squeaks transform from a hill shape—seen in the spectrograms above—and flatten to become an adult squeak call. Squeals are often used during play and may indicate excitement or possibly aggression.

Interestingly, manatee vocalizations exhibit similarities to the way dogs bark or cats meow. Just as you might notice variations in your pet’s vocalizations depending on whether they’re hungry, want to go outside, or play, manatees also make subtle changes in their vocalizations based on their behavior. Scientists analyze these subtle variations in vocalizations to understand the function of manatee calls. For instance, manatees tend to extend the length of their calls when feeling scared. Additionally, during play, they may have multiple changes in the pitch of their call. You can hear examples of these calls on our website at savethemanatee.org/sounds.

There are geographic differences in manatee vocalizations, too. Antillean and Florida manatees produce similar types of calls, but their vocalizations typically differ in pitch. One reason for this could be because Florida manatees are larger than Antillean manatees , and larger animals tend to produce lower-pitched vocalizations—like the contrast between a mouse and an elephant. Another potential factor is the habitat. Just as your voice may sound different in a cave compared to an open field, a similar phenomenon might contribute to the slight variations in manatee vocalizations between the two subspecies. Additionally, African manatees also produce vocalizations similar to those of Florida and Antillean manatees.

There is still a lot to discover about manatee vocalizations. Scientists can use this information to learn more about what habitat is important to manatees and estimate the number of animals that use the habitat.