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Rhynchonycteris naso in three phases
Ultrasound / human hearing range
(by Danny Zurc & Alejandro Valencia-Tobon)

Bat sound signals appear to be divided into three phases: search, approach and terminal phase (this latter one also called ‘feeding buzz’).

These phases are indications of the bat’s activity: in the search phase, bats seek food and, while doing this, each individual is analysing what is happening in its habitat.

Encountering possible prey, bats go towards it, emitting pulses at shorter time intervals (approach phase).

Finally, during the feeding buzz, bats are so close to their possible prey that pulses are emitted at incredibly short time intervals in order to rapidly obtain information about what is happening and thus have a successful hunt. This process is repeated over and over again.

These ultrasonic vocalisation records can also be used for biological identification because bats’ ultrasound signals are unique to each species. Here we have Rhynchonycteris naso, which is an interesting animal from South and Central America.

Individuals of this species emit ultrasound from 95.0 to 103.5 kHz, which means that they produce high intensity sounds. With this information we are able to study how bats navigate and use echolocation.

We then convert the recordings to the human hearing range to allow people to audibly appreciate the sounds.

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