Proceedings of the Institute of Acoustics PUPS OF THE DEGU (OCTODON DEGUS) INCLUDE ULTRASONIC FREQUENCIES IN CARE-ELICITING CALLS

Previous research into the juvenile vocalisations of the degu (Octodon degus), a semi-fossorial caviomorph rodent from central Chile, revealed interesting features of the calls used to elicit care from an adult, suggesting features present in the ultrasonic region. Here, it is determined that such vocalisations can include frequencies from 2.8 – 61.6 kHz, demonstrating ultrasonic harmonics well above the range that was previously recorded, although most energy is contained within the 10 kHz region. This provides the first reported case of ultrasound production by the species. These ‘loud whistle ’ calls were found to have properties that varied significantly between behavioural contexts and between litters, suggesting the potential for individual litter and context recognition by adult degus. Features of the vocalisation such as duration were found to vary significantly with pup age, indicating changes to the qualities with pup growth and development. Finally, the recommended recording range for this species is given as 20 Hz – 65 kHz