Indicator: CO-48 Area disturbed/potentially disturbed by seismic surveys

Data

The map shows overlays of seismic survey lines with migration paths, breeding, resting and other significant areas of whales, seagrass, dugong density and dugong protected area data.

Source: National Oceans Office 2006, National Marine Atlas, viewed 29 May 2006, http://www.oceans.gov.au/Non-fish Atlas.jsp map 64!;

The National Oceans Office map of seismic surveys alone, without the overlapping data may give a clearer idea of the potential area affected by seismic noise.

What the data mean

Humpback whales migration routes are frequently intersected by seismic survey activity, all along the western coast, in the Great Australian Bight, throughout Bass Strait and around the south eastern coast of the continent including Tasmania, north to central NSW. Several aggregated areas of significance for Humpback and Southern Right Whales, and dugong areas, are also intersected.

Data Limitations

Understanding of the impact of seismic surveys on marine animals, especially on animals such as whales, who rely on sonar as their principal sensory tool, is limited, so this indicator can at best give an idea of what type of animals might be affected and where.

The data give an idea of the spatial scope for disturbance of some marine mammals by seismic noise, but it has not been possible to estimate an actual area affected by seismic noise. The data show only the lines of seismic surveys, not the area (or volume) of ocean habitat affected by them.

Issues for which this is an indicator and why

Coasts and Oceans — Direct pressure of human activities on coasts and oceans - Direct pressures of harvesting non-living materials 

Area affected by seismic surveys may be very difficult to estimate. Number of surveys and estimated length of survey lines occurring in known habitat of selected threatened species (eg whales, dugongs, turtles) will give an indication of some of the species that are potentially under pressure from these activities.

Other indicators for this issue:

Biodiversity — Pressures on biodiversity - Pressures on marine biodiversity: pressures of energy and mineral exploration and extraction 

Seismic surveys used in oil and gas exploration have the potential; to place pressure on marine biodiversity. Number of surveys and estimated length of survey lines occurring in known habitat of selected threatened species (eg whales, dugongs, turtles) will give an indication of some of the species that are potentially under pressure from these activities.

Other indicators for this issue: