The Australian Government works closely with maritime organisations and industry to ensure potential impacts on whales and dolphins from industry-related activities are avoided. Guidelines for operations that may affect whales and dolphins have been established, such as seismic survey guidelines and whale watching guidelines.
The petroleum industry uses an exploration technique called seismic surveying to locate potential oil and gas reserves (both on land and under water). This type of underwater exploration directs acoustic sound waves into the rock beneath the sea floor from a purpose-built seismic vessel. During seismic surveys, a predominantly low frequency (10 - 300 Hz), high intensity (215-250 dB) sound pulse is emitted every few seconds by the array of guns used by the survey vessel. The sound pressure which is emitted can vary depending on the size of the array being used.
When these sound waves reach the different layers of rock under the sea bed, they are reflected back to the surface of the water and are recorded by waterproof microphones (hydrophones) which are towed behind the seismic vessel. The microphones capture the different sound waves which have been reflected back by the rock beneath the sea bed enabling a map to be made of these layers. Geologists can then analyse these maps to locate potential oil and gas deposits.
The impacts of seismic surveying on whales are not fully understood. The Australian Government has developed guidelines to help the industry to avoid or minimise impacts on whales and dolphins from seismic survey activities. These guidelines have recently been reviewed to ensure ongoing best practice. Businesses conducting seismic operations need to consider whether their activities require approval under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
- Seismic guidelines - Interaction between offshore seismic exploration and whales - EPBC Act Policy Statement 2.1
- Sonar and seismic impacts
The use of some fishing equipment can be hazardous to whales and dolphins. Animals become caught in equipment which can result in serious injury and even death. A whale or dolphin entangled in netting or fishing line may be seriously injured through cuts and abrasions, or even drown. Entanglements can also affect the animal's ability to catch food and places it at risk to predators such as sharks.
The Australian Government and state government departments are working with the fishing industry and the Australian Fisheries Management Authority (AFMA) to develop ways to help minimise the impact fishing can have on whales and dolphins. The EPBC Act allows the Department to evaluate the environmental performance of fisheries through:
- Strategic assessments
- Impacts on protected species (including whales and dolphins)
- Export approvals
Strategic Assessments of Fisheries
Through the EPBC Act the Department of the Environment, Water, Heritage and the Arts has a key role in promoting ecologically sustainable management of fisheries and assessing their environmental performance. This is done through the assessment of fisheries managed under Commonwealth legislation and state export fisheries through three main mechanisms:
- the strategic assessment of fisheries;
- assessments relating to impacts on protected marine species; and
- assessments for the purpose of export approval.
Australian Fisheries Management Authority
AFMA is the statutory authority responsible for the efficient management and sustainable use of Commonwealth fish resources on behalf of the Australian community.
- www.afma.gov.au - Australian Fisheries Management Authority
Since the end of whaling in Australia many species of whales have begun to increase in numbers in Australian waters. This has enabled Australia to have and promote a sustainable whale watching industry that allows the public to view and learn about these animals in their natural habitat.
With this important industry comes the responsibility to ensure that potential impacts from watching whales and dolphins (either commercially or recreationally) are managed appropriately. The Australian Government regularly reviews the national guidelines for the whale watching industry.