Several projects are available through CEAL at the PhD, Masters, and Honours levels.  Please contact the lab for further information on any of our available projects.

Effects of noise on the acoustic behaviour in humpback whales (PhD)

This project will focus on the effects of various sources of noise (wind, ships, recreational vessels, seismic air guns and biological (singing whales and snapping shrimp) on the acoustic behaviour of humpback whales. It will determine the potential active space of their non-song vocal sounds and surface-generated sounds, and model the decrease in this space with noise. It will also look at signal masking with various noise sources.


The use of surface-generated sounds in the presence of singers (Honours)

Humpback whales emit two main communication sounds; vocal sounds and sounds generated on the surface (by breaching and slapping their pectoral and tail fins). Groups of whales tend to switch their communication strategy from using primarily vocal sounds, to using primarily surface-generated sounds, in higher wind noise. Whales also emit vocal sounds at higher levels in increased wind noise and therefore utilise two different methods to overcome potential deleterious effects communicating in noise. Interestingly, whales must also consider their social environment when signalling. Groups (especially females with a nursing calf) emit vocal sounds at lower levels in the presence of singing whales, despite the song being a potential source of noise. This is presumably to avoid the unwanted attention of a singing male. Therefore there are two competing effects; wind noise causing an increase in vocal level, and singing whales causing a decrease in vocal level. It is unknown, however, if whales emit fewer surface-generated sounds in the presence of singing whale (potentially to avoid the unwanted attention of the male), and if noise levels change this response. This project will determine if singing whales have an effect on the use of surface-generated sounds in humpback whale groups. It will also consider the potential effect of noise within this response to their social environment.

This project will be supervised by Dr. Rebecca Dunlop, Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science


The ‘dolphin chirp’ – a potential new dolphin vocal sound (Honours)

The ‘dolphin chirp’ is a short, relatively low-frequency downsweep sound, which has been recorded (using a fixed hydrophone array) quite often off the coast of Peregian Beach on the Sunshine Coast. Groups of bottlenose dolphins are commonly seen around the hydrophone array therefore it is likely that this sound comes from bottlenose dolphins. However, this ‘chirp’ sound is quite unique, in that there are no similar sounds that have been attributed to bottlenose, or indeed any species, of dolphin in the literature. Preliminary work has acoustically positioned these chirp sounds to other dolphin sounds (click and whistle sounds) on a few occasions.  These chirp sounds also seem to have little variation in structure, and may be significantly louder than other dolphin sounds, therefore may be a useful sound for acoustically monitoring this dolphin population. This project will carry out further analysis on the ‘chirp’ sounds to provide further evidence that this is a novel sound from bottlenose dolphins.  It will estimate the variance in sound structure within and between chirp bouts, compare sound parameters with other commonly heard tonal dolphin sounds (whistles) and determine if there are any changes in the frequency of ‘chirp’ acoustic detections over time (2002 – 2015).  Results of this study will likely add a novel sound to the bottlenose dolphin repertoire, and provide some evaluation of its potential to be used in acoustic monitoring of this population of dolphins.

This project will be co-supervised by Dr. Rebecca Dunlop and Associate Professor Michael Noad, Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science.


Information content within commonly used sounds in the domestic dog (Honours)

Many vocal sounds simultaneously contain static and flexible information within the sound type.  For example, a particular sound type such as the ‘bark’ may contain static information such as the sex, size and location of the signaller, along with flexible information (information that is likely to change) such as signaller motivation (e.g. fearful, aggressive, playful). These static and flexible features should therefore be related to the signaller’s sex, size, behaviour and internal physiology. Due to the difficulties in simultaneously measuring these signaller features in animals (especially wild animals), studies relating the physical and physiological attributes of the signaller, to various vocal parameters of particular sound types (such as the frequency and duration at which they are emitted) are rare. However, the domestic dog, being a species that is easy to collect these data from, can act as a model species with which to further explore the informational content of vocal signals. This project will determine if common sounds produced by domestic dogs contain both static and flexible information related to the signaller’s size, sex, behaviour, internal physiology and motivation.

This project will be supervised by Dr. Rebecca Dunlop, Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science