Geraldton/Geelvink Channel Surveys

Seismic Monitoring Project

Aerial survey track lines designed to determine the reaction of migrating humpback whales to an operating seismic vessel in the Geelvink Channel, Western Australia, during 2002

Background

Previous studies by collated by Jenner et al. (2001) have found that in general, humpback whales on the Western Australian coast appear to be found within the 200m depth contour between the months of June and November. However, this simplistic description of the whales’ migratory paths is not sufficient for planning or conducting the potentially disruptive exploratory seismic surveys for the oil and gas industry. In the case of the Cheryl, Rita and Jean areas near Geraldton, Western Australia (28.7° S), no detailed knowledge of the migratory timing or patterns was available. Jenner et al. (2001) had suggested (based on extrapolated data) that the southern migration at this latitude would peak during late September.

Accepted knowledge (Chittleborough,1953, 1965) regarding the 4 week delay in the arrival of cow/calf pairs at a given location after the southbound peak has passed, forecast that the timing for the seismic operation and the arrival of cow/calf pairs in the Geraldton area would coincide. Pressure from the commercial rock lobster fishery, which began operations in mid-November, meant that delaying the seismic operations to allow cow/calf pairs to pass by the region was not acceptable. Environment Australia (EA) granted ROC Oil a Cetacean Interference Permit with 8 special conditions designed to mitigate the potential impacts of the seismic exploration activities on migrating humpback whales.

ROC Oil commissioned this study, among several others, in an effort to get to the bottom of the debate regarding seismic/whale interactions.

Download Report

Positions of 361 pods of humpback whales observed during the aerial surveys.

UA-17929247-1