WWMSP8.3 aims to address gaps in our understanding of the ecology of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Owen Anchorage and Cockburn Sound in order to improve the scientific basis for environmental impact assessment (EIA) of the proposed Westport port development.
Broad-scale distribution and habitat modelling of Indo-Pacific bottlenose dolphins
This report presents the results from analysing data collected between 2011 and 2015, focusing on the broad-scale spatial and temporal distribution of the two communities of Indo-Pacific bottlenose dolphins’ resident in Owen Anchorage and Cockburn Sound.
A total of 72 surveys were conducted in Owen Anchorage, and 73 surveys were conducted in Cockburn Sound. These surveys followed three systematic zigzag survey routes that were pre-designed in each region, spanning from June 2011 and May 2015. During these surveys, we performed photo-identification and recorded environmental variables such as water depth, sea surface temperature, and water visibility for dolphin sightings within the study area. We observed a total of 94 dolphin groups (incl. 36 foraging and 13 resting) in Owen Anchorage and 119 dolphin groups (Incl. 49 foraging and 19 resting) in Cockburn Sound, with the majority being mixed-sex groups. Additionally, calves, which are individual dolphins still dependent on their mothers, were present in most of the groups with adult dolphins.
