Cetacean strandings in Tasmania

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Cetacean strandings in Tasmania occur for a number of reasons, with Tasmania considered a "'hotspot" for the event. [1] Between 1825 and 1986, 213 stranding events had been recorded, involving 22 species, and over 3000 individuals. [2]

Contents

Causes

Cetacean strandings may occur for a number of reasons. These include natural causes, such as coastal topography and tidal patterns, searching for food, or a change in electromagnetic fields that could disorient them. Other causes include boat strikes, fishing. and pollution, that could result in injuries and stranding. Pilot whales in particular, living in strong social units, sometimes strand themselves to be with family. [3] [4]

Stranding events

Macquarie Harbour, where many of the strandings have occurred Macquarie Harbour SE.jpg
Macquarie Harbour, where many of the strandings have occurred

2020 long-finned pilot whale stranding

In September 2020, more than 450 long-finned pilot whales stranded in Macquarie Harbour on the western coast of Tasmania, in Australia's worst-ever stranding event. Most were stranded on sandbanks and beaches around the mouth of the harbour. 50 were rescued, with the balance, 380 whales, dying. [5] [6]

2022 pilot and sperm whale strandings

In September 2022, fourteen stranded sperm whales at King Island, most of which appeared to be young males according to the Department of Natural Resources and Environment spokesperson, were dead when they were reported in the afternoon of 19 September 2022. [7] [8]

Two days later, on 21 September, 230 pilot whales, including young, [9] stranded at Macquarie Heads, near to the location of and exactly two years after the 2020 stranding. The remote location made it difficult for rescue teams to reach the whales, with teams from the Environment Tasmania Marine Conservation Program working with the Tasmania Parks and Wildlife Service and Tasmania Police. The West Coast Council urged members of the public to stay clear unless they were invited by the rescue teams to assist, saying that "Having extra people can really hinder how they go about their rescue efforts." Locals have been covering the animals with blankets and pouring buckets of water over them. [10] As of the morning of 22 September, 35 whales were still alive. [11] [12] Tanya Plibersek, Minister for the Environment and Water, wrote on Twitter: "Very distressing to see a large number of whales stranded in Tasmania. Many thanks to the experts and emergency personnel on site to assist efforts." [13]

Related Research Articles

<span class="mw-page-title-main">Cetacea</span> Infraorder of mammals

Cetaceans are an infraorder of aquatic mammals that includes whales, dolphins, and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively carnivorous diet. They propel themselves through the water with powerful up-and-down movement of their tail which ends in a paddle-like fluke, using their flipper-shaped forelimbs to maneuver.

<span class="mw-page-title-main">Macquarie Island</span> Sub-Antarctic island of Australia

Macquarie Island is an island in the southwestern Pacific Ocean, about halfway between New Zealand and Antarctica. Regionally part of Oceania and politically a part of Tasmania, Australia, since 1900, it became a Tasmanian State Reserve in 1978 and was inscribed as a UNESCO World Heritage Site in 1997.

<span class="mw-page-title-main">Sowerby's beaked whale</span> Species of mammal

Sowerby's beaked whale, also known as the North Atlantic or North Sea beaked whale, is a species of toothed whale. It was the first mesoplodont whale to be described. James Sowerby, an English naturalist and artist, first described the species in 1804 from a skull obtained from a male that had stranded in the Moray Firth, Scotland, in 1800. He named it bidens, which derives from the two teeth present in the jaw, now known to be a very common feature among the genus.

<span class="mw-page-title-main">Gray's beaked whale</span> Species of mammal

Gray's beaked whale, sometimes known as Haast's beaked whale, the scamperdown whale, or the southern beaked whale, is one of the better-known members of the genus Mesoplodon. This species is fairly gregarious and strands relatively frequently for a beaked whale. In the Māori language, this species is called hakurā or iheihe.

<span class="mw-page-title-main">Short-finned pilot whale</span> Species of mammal

The short-finned pilot whale is one of the two species of cetaceans in the genus Globicephala, which it shares with the long-finned pilot whale. It is part of the oceanic dolphin family (Delphinidae).

<span class="mw-page-title-main">Pilot whale</span> Genus of dolphins in the order Cetacea

Pilot whales are cetaceans belonging to the genus Globicephala. The two extant species are the long-finned pilot whale and the short-finned pilot whale. The two are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between the species. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters. Pilot whales are among the largest of the oceanic dolphins, exceeded in size only by the orca. They and other large members of the dolphin family are also known as blackfish.

<span class="mw-page-title-main">False killer whale</span> Species of oceanic dolphin in the genus Pseudorca

The false killer whale is a species of oceanic dolphin that is the only extant representative of the genus Pseudorca. It is found in oceans worldwide but mainly in tropical regions. It was first described in 1846 as a species of porpoise based on a skull, which was revised when the first carcasses were observed in 1861. The name "false killer whale" comes from having a skull similar to the orca, or killer whale.

<span class="mw-page-title-main">Southern right whale dolphin</span> Species of mammal

The southern right whale dolphin is a small and slender species of cetacean, found in cool waters of the Southern Hemisphere. It is one of two species of right whale dolphin. This genus is characterized by the lack of a dorsal fin. The other species, the northern right whale dolphin, is found in deep oceans of the Northern Hemisphere and has a different pigmentation pattern than the southern right whale dolphin.

<span class="mw-page-title-main">Macquarie Harbour</span> Large inlet on the West Coast of Tasmania

Macquarie Harbour is a shallow fjord in the West Coast region of Tasmania, Australia. It is approximately 315 square kilometres (122 sq mi), and has an average depth of 15 metres (49 ft), with deeper places up to 50 metres (160 ft). It is navigable by shallow-draft vessels. The main channel is kept clear by the presence of a rock wall on the outside of the channel's curve. This man-made wall prevents erosion and keeps the channel deep and narrow, rather than allowing the channel to become wide and shallow. A reported Aboriginal name for the harbour is Parralaongatek.

<span class="mw-page-title-main">Cetacean stranding</span> Phenomenon in which a whale becomes stuck on a beach, often causing the whales death

Cetacean stranding, commonly known as beaching, is a phenomenon in which whales and dolphins strand themselves on land, usually on a beach. Beached whales often die due to dehydration, collapsing under their own weight, or drowning when high tide covers the blowhole. Cetacean stranding has occurred since before recorded history.

Ocean Beach is a long stretch of beach running north of Macquarie Heads and Hells Gates on the West Coast of Tasmania. It is close to Strahan and parallel to the Strahan Airport runway. It extends as far north as Trial Harbour and the coast immediately west of Zeehan.

<span class="mw-page-title-main">River Thames whale</span> Whale stuck in the River Thames

The River Thames whale, affectionately nicknamed Willy by Londoners, was a juvenile female northern bottlenose whale which was discovered swimming in the River Thames in central London on Friday 20 January 2006. According to the BBC, she was five metres (16-18ft) long and weighed about twelve tonnes (24,400 lb). The whale appeared to have been lost, as her normal habitat would have been around the coasts of the far north of Scotland and Northern Ireland, and in the seas around the Arctic Ocean. It was the first time the species had been seen in the Thames since records began in 1913. She died from convulsions as she was being rescued shortly after 19:00 GMT on 21 January 2006.

<span class="mw-page-title-main">British Divers Marine Life Rescue</span> United Kingdom charity organisation

British Divers Marine Life Rescue (BDMLR) is a British charity established in 1988 and is the United Kingdom's leading frontline marine mammal response organisation. It utilises a network of trained volunteers around the country to respond to marine mammals potentially in need of assistance around the country via a public 24hr hotline and callout system. The organisations main areas of operation are in the United Kingdom and its territorial waters; however, the charity is often requested to provide assistance and training in marine mammal rescue by international governments and charitable organisations due to their vast wealth of knowledge, experience and available equipment including Canada, the Falkland Islands, Kenya, Ireland, Italy, Kazakhstan, Malta and Abu Dhabi amongst others.

<span class="mw-page-title-main">Hibbs Pyramid</span> Island in Tasmania, Australia

The Hibbs Pyramid is a pyramidal dolerite island, located in the Indian Ocean, off the south western coast of Tasmania, Australia. The island is contained within the Southwest National Park, part of the Tasmanian Wilderness World Heritage Site.

<span class="mw-page-title-main">Cockle Creek (Tasmania)</span> Location in Tasmania, Australia

Cockle Creek is the farthest point south one can drive in Australia. It is located on Recherche Bay on the edge of the Southwest National Park, part of the Tasmanian Wilderness World Heritage Area.

Point Hibbs is a headland on the south-west coast of Tasmania, Australia. The headland is located south of the most southern point of Macquarie Harbour, and west of the Gordon River. It is the next named feature along the coast south of Cape Sorell that is used to delineate sections of the coast. Like South West Cape, it is used as a reference point for nearby wrecks.

<span class="mw-page-title-main">Walker Island (Northern Tasmania)</span> Island in Tasmania, Australia

The Walker Island, sometimes also Walker's Island, is a 700-hectare (1,700-acre) island located in Bass Strait, lying off the northwest coast of Tasmania, Australia. The island, separated from the Tasmanian mainland by a highly tidal area known as Robbins Passage, lies north of the adjacent Robbins Island.

<span class="mw-page-title-main">Cetacean strandings in Ghana</span>

Cetacean strandings in Ghana appear to be becoming more common. Whales washing ashore may be due to ship strike, population dynamics, or an increase in human coverage and reporting. There are at least 28 species of cetaceans — seven baleen whales and 21 toothed whales — in the Gulf of Guinea, of which Ghana’s coast covers 550 km from Aflao to Axim. Scientific approaches to cetacean diversities have not been taken until recently, and 18 species were confirmed during researches.

<span class="mw-page-title-main">Drift whale</span>

A drift whale is a cetacean mammal that has died at sea and floated into shore. This is in contrast to a beached or stranded whale, which reaches land alive and may die there or regain safety in the ocean. Most cetaceans that die, from natural causes or predators, do not wind up on land; most die far offshore and sink deep to become novel ecological zones known as whale falls. Some species that wash ashore are scientifically dolphins, i.e. members of the family Delphinidae, but for ease of use, this article treats them all as "drift whales". For example, one species notorious for mass strandings is the pilot whale, also known as "blackfish", which is taxonomically a dolphin.

References

  1. "Troublesome teenagers? Herd mentality? What we know about why Tasmania has another mass whale stranding". ABC News. 21 September 2022. Retrieved 21 September 2022.
  2. Nicol, Douglas James. "The Tasmanian Cetacean Stranding Record: A Review of the Cetacean Strandings in Tasmanian Waters and an Examination of Possible Causes" (PDF). University of Tasmania.{{cite web}}: CS1 maint: url-status (link)
  3. "Tasmania's whale stranding tragedy explained". Australian Geographic. 23 September 2020. Retrieved 21 September 2022.
  4. "Why do whales beach themselves? We're partially to blame". Animals. 29 March 2021. Retrieved 21 September 2022.
  5. "380 whales dead in worst mass stranding in Australia's history". the Guardian. 23 September 2020. Retrieved 21 September 2022.
  6. "Australia says majority of 470-strong beached whale pod has died". Reuters. 23 September 2020. Retrieved 21 September 2022.
  7. "'It was pretty horrific': Sperm whales stranded off Tasmania mostly young males, experts say". ABC News. 20 September 2022. Retrieved 21 September 2022.
  8. "Sperm whales die in mass stranding on Australian beach". BBC News. 20 September 2022. Retrieved 21 September 2022.
  9. Mahony, Jack (21 September 2022). "Shocking pictures reveal extent of stranded whales on Tasmanian beach". Sky News. Retrieved 22 September 2022.{{cite web}}: CS1 maint: url-status (link)
  10. "Whale stranding: 230 whales stranded on Tasmanian beach". BBC News. 21 September 2022. Retrieved 22 September 2022.
  11. "Race against time to save whales, with only 35 still alive after 230 beached in mass stranding". ABC News. 21 September 2022. Retrieved 21 September 2022.
  12. "Rescuers rush to save hundreds of pilot whales stranded on Tasmanian beach". the Guardian. 21 September 2022. Retrieved 21 September 2022.
  13. "Rescue effort under way after some 230 whales beached in Tasmania". www.aljazeera.com. Retrieved 21 September 2022.