Why do whales and dolphins strand?
There have been many instances of whales and dolphins stranding themselves, either singly or in groups, on beaches not only in Australia but also around the world.
Why whale and dolphin species strand is not fully understood, although there are a number of theories about why strandings occur.
- Some single strandings may be accounted for by a whale dying at sea and being washed ashore, although many strandings are believed to occur due to other factors.
- Interestingly, the majority of strandings involve those species that are usually found in deep oceanice waters.
- A recent theory suggests that these species follow schooling fish or other prey into shallow water, they can then become disorientated and strandings occur.
- It is also thought that the shape of the beach and coastline may contribute to strandings. If the beach typography is wide and gently sloping, the shoreline may not be detected by the reflection of sonar pulses and whales or dolphins may swim too close to the shore.
- Panic from being trapped may result in beaching, if for example, smaller whales are being hunted by predators such as sharks or killer whales which force them onto the shore, or if they cannot find their way out of a bay with a narrow mouth.
The species that most often strand on Australian beaches are those that use echolocation or sonar for navigation such as pilot whales and sperm whales. Because they are sometimes found in large pods, some strandings involve large numbers of animals at one time.
Government responses
The Australian Government and state governments have worked together over many years to establish strong communications and operations networks to manage and respond to events such as whale strandings. More than 80 per cent of Australian whale strandings take place in Tasmania, and the Tasmanian Department of Primary Industries and Water has some of the nation's experienced and well-equipped whale stranding response teams.
Australia has a world-leading response capacity to assist individuals and groups of whales in distress in cases where assistance is physically and logistically possible. Unfortunately not all stranded animals can be saved. In cases where larger baleen whales or calves are beached, it is usually as a result of injury or illness. Even if there is a successful refloating attempt made, the whale may strand again at another part of the coast.
Report a stranding
State and Territory governments are responsible for conservation and protection of whales in coastal waters (out to the 3 nautical mile limit). This includes responding to strandings and entangled whales. Should you come across an entangled whale or stranded animal please report it to your State Environment Department immediately.
All state conservation departments have Stranding Contingency Plans. Volunteers often attend strandings and assist the local authorities to get many cetaceans back out to sea. You can phone the state and territory stranding hotlines listed below.
Whale and dolphin rescue hotlines
New South Wales |
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ORRCA Whale and Dolphin Rescue Ph: 02 9415 3333 |
Northern Territory |
Marine Wildwatch Ph: 1800 453 941 |
Queensland |
RSPCA Ph: 1300 ANIMAL (1300 264 625) |
South Australia |
National Parks and Wildlife Service Ph: 1300 650 411 Quote 465393 |
Tasmania |
Department of Primary Industries, Water and Environment Ph: 0427 942 537 |
Victoria |
Whale and Dolphin Emergency Hotline Ph: 1300 136 017 |
Western Australia |
Wildcare Ph: 08 9474 9055 |