Bass Strait

Bass Strait /ˈbæs/ is a sea strait separating Tasmania from the Australian mainland, specifically the state of Victoria.

Extent

The International Hydrographic Organization defines the limits of Bass Strait as follows:^[1]

On the west. The eastern limit of the Great Australian Bight [being a line from Cape Otway, Australia, to King Island and thence to Cape Grim, the northwest extreme of Tasmania].

On the east. The western limit of the Tasman Sea between Gabo Island and Eddystone Point [being a line from Gabo Island (near Cape Howe, 37°30'S) to the northeast point of East Sister Island (148°E) thence along the 148th meridian to Flinders Island; beyond this Island a line running to the Eastward of the Vansittart Shoals to [Cape] Barren Island, and from Cape Barren (the easternmost point of [Cape] Barren Island) to Eddystone Point (41°S) in Tasmania].

Bass Strait is sometimes considered part of the Pacific Ocean.^[2] The IHO in its Limits of Oceans and Seas (1953)^[1] states that straits joining two seas have been allotted to one of them, but does not list such allotments. It groups Bass Strait with the South Pacific Ocean, the Great Australian Bight and the Tasman Sea. The Australian Hydrographic Service does not consider it to be part of the Southern Ocean, using the expanded Australian definition, and states that it lies within the Tasman Sea.^[3] The strait between the Furneaux Islands and Tasmania is Banks Strait, a subdivision of Bass Strait.

Discovery and exploration

The strait was named after George Bass, after he and Matthew Flinders passed through it while circumnavigating Van Diemen's Land (now named Tasmania) in the Norfolk in 1798–99. At Flinders' recommendation, the Governor of New South Wales, John Hunter, in 1800 named the stretch of water between the mainland and Van Diemen's Land "Bass's Straits".^[4] Later it became known as Bass Strait.

The existence of the strait had been suggested in 1797 by the master of the Sydney Cove when he reached Sydney after deliberately grounding his foundering ship and being stranded on Preservation Island (at the eastern end of the strait). He reported that the strong south westerly swell and the tides and currents suggested that the island was in a channel linking the Pacific and southern Indian Ocean. Governor Hunter thus wrote to Joseph Banks in August 1797 that it seemed certain a strait existed.^[5]

Conditions

Approximately 240 km wide at its narrowest point and generally around 50 metres deep, it contains many islands, with King Island and Flinders Island home to substantial human settlements.

Like the rest of the waters surrounding Tasmania, and particularly because of its limited depth, it is notoriously rough, with many ships lost there during the 19th century. A lighthouse was erected on Deal Island in 1848 to assist ships in the eastern part of the Straits, but there were no guides to the western entrance until the Cape Otway Lighthouse was first lit in 1848, followed by another at Cape Wickham at the northern end of King Island in 1861.

Maritime history

Strong currents between the Antarctic-driven southeast portions of the Indian Ocean and the Tasman Sea's Pacific Ocean waters provide a strait of powerful, wild storm waves. To illustrate its wild strength, Bass Strait is both twice as wide and twice as rough as the English Channel. The shipwrecks on the Tasmanian and Victorian coastlines number in the hundreds, although stronger metal ships and modern marine navigation have greatly reduced the danger.

Many vessels, some quite large, have disappeared without trace, or left scant evidence of their passing. Despite myths and legends of piracy, wrecking and alleged supernatural phenomena akin to those of the Bermuda Triangle, such disappearances can be invariably ascribed to treacherous combinations of wind and sea conditions, and the numerous semi-submerged rocks and reefs within the Straits.^[6]

Despite the strait's difficult waters it provided a safer and less boisterous passage for ships on the route from Europe or India to Sydney in the early 19th century. The strait also saved 1,300 km (700 nmi) distance on the voyage.^[5]

Islands

There are over 50 islands in Bass Strait. Major islands include:

Western section:

• King Island
• Three Hummock Island
• Hunter Island
• Robbins Island

South eastern section:

• Furneaux Group
  • Flinders Island (where the surviving Aboriginal Tasmanians were exiled)
  • Cape Barren Island
  • Clarke Island
  • Sister Islands Group
  • and several other islands

North eastern section:

• Kent Group
  • Deal Island
  • and 3 smaller islands
• Hogan Island
• Curtis Island

Natural resources

A number of oil and gas fields exist in the eastern portion of Bass Strait, in what is known as the Gippsland Basin. Most large fields were discovered in the 1960s, and are located about 50 km to 65 km off the coast of Gippsland in water depths of about 70 m.^[7]:484 These oil fields include the Halibut Field discovered in 1967, the Cobia Field discovered in 1972, the Kingfish Field, the Mackerel Field, and the Fortescue Field discovered in 1978.^[7]:484 Large gas fields include the Whiptail field, the Barracouta Field, the Snapper Field, and the Marlin Field.^[7]:484 Oil and gas are produced from the Cretaceous-Eocene clastic rocks of the Latrobe Group, deposited with the breakup of Australia and Antarctica.^[7]:485

The western field, known as the Otway Basin, was discovered in the 1990s offshore near Port Campbell. Its exploitation began in 2005.

The oil and gas is sent via a pipeline to gas processing facilities and oil refineries at Longford, Western Port, Altona and Geelong, as well as by tanker to New South Wales.

Infrastructure

Transport

The fastest and often the cheapest method of travel across Bass Strait is by air. The major airports in Tasmania are Hobart International Airport and Launceston Airport, where the main airlines are Jetstar Airways and Virgin Australia. Qantas and Tiger Airways Australia also operate services. The smaller airports in the north of the state and on the islands in the strait are served either by Regional Express Airlines, QantasLink or King Island Airlines.

Ferries

See also Bass Strait Ferries

The domestic sea route is serviced by two Spirit of Tasmania passenger vehicle ferries, based in Devonport, Tasmania. The ships travel daily in opposite directions between Devonport and Station Pier in Melbourne, as overnight trips with additional daytime trips during the peak summer season.^[8]

Energy

The Basslink HVDC electrical cable has been in service since 2006. It has the capacity to carry up to 630 megawatts of electrical power across the strait.

Alinta owns a submarine gas pipeline, delivering natural gas to large industrial customers near George Town, as well as the Powerco gas network in Tasmania.

Communications

The first submarine communications cable across Bass Strait was laid in 1859. Starting at Cape Otway, Victoria, it went via King Island and Three Hummock Island, made contact with the Tasmanian mainland at Stanley Head, and then continued on to George Town. However it started failing within a few weeks of completion, and by 1861 it failed completely.

Tasmania is currently connected to the mainland via two Telstra-operated fibre optic cables; since 2006, dark fibre capacity has also been available on the Basslink HVDC cable.

Other submarine cables include:

Date	Northern end	Southern end	Companies (Manufacturer / Operator)	Details
1859–1861	Cape Otway	Stanley Head	Henley's Telegraph Works Tas & Vic Govts	System 260 km (140 nmi)
1869-?	?	?	Henley's Telegraph Works Australian Govt	System 326 km (176 nmi)
1885-?	?	?	Telcon Australian Government
1909–1943	?	?	Siemens Brothers Australian Government	System 528 km (285 nmi) Was reused at Torres Strait
1936	Apollo Bay	Stanley	Siemens Brothers Australian Government	First telephone cable, failed after only six months[9]
1995-	Sandy Point	Boat Harbour	ASN Telstra	First fibre optic cable
2003-	Inverloch	Stanley	ASN Calais Telstra
2005-	Loy Yang	Bell Bay	Basslink	First electrical transmission cable

Popular culture

See also Bass Strait Triangle

The issue of planes, ships and people having been lost in the strait over time has spawned a number of theories. Perhaps the most thorough list of losses and disappearances has been the oft re-printed book of Jack Loney^[10] though it is possible that most losses can be adequately explained by extreme weather events.^[11]

On the popular Australian soap Neighbours, one of its most dramatic storylines unfolded when a 1940s themed joy flight to Tasmania was sabotaged by a bomb. The plane crashed into Bass Strait in the middle of the night and many character's lives were put at risk, with some drowning.

In 1978, one of the most famous UFO incidents in Australian history occurred over Bass Strait. Frederick Valentich was flying a small aeroplane over the strait when he reported to personnel at a local airport that a strange object was buzzing his plane. He then claimed that the object had moved directly in front of his plane; the airport personnel then heard a metallic "scraping" sound, followed by silence. Valentich and his plane subsequently vanished and neither Valentich nor his plane were ever seen again.

Non-motorised crossings

Bass Strait is regularly crossed by sailing vessels, including during the annual Melbourne to Hobart Yacht Race. The Sydney to Hobart Yacht Race passes generally east of the strait but is affected by its weather conditions. Australian Olympic bronze medalist Michael Blackburn set a record in October 2005 when he crossed the strait in just over 13 hours in a Laser sailing dinghy.^[12]

Lone rower David Bowen (Mt Martha) crossed Bass Strait in 1971 rowing a 20' dory, leaving from Devonport he landed on Wilson's Promontory.^[13] Tammy van Wisse swam part of the strait in 1996, from King Island to Apollo Bay in Victoria, a distance of about 100 km in 17 hours and 46 minutes.^[14][15] Andrew McAuley was the first person to successfully cross Bass Strait non-stop in a sea kayak in 2003. He made two more successful crossings of Bass Strait before he disappeared in the Tasman Sea in February 2007; his body was never recovered.^[16] Other experienced sea kayakers have since made the crossing, usually by island hopping on the eastern side of the strait.^[17][18][19] The first windsurfer crossing was in 1982 by Mark Paul and Les Tokolyi.^[20] Kitesurfers have also completed the crossing.^[21][22] The first crossing by paddleboard was made by Jack Bark, Brad Gaul and Zeb Walsh, leaving Wilsons Promontory in Victoria on 25 February 2014 and arriving at Cape Portland in Tasmania's north-east on 4 March 2014.^[23]

References

External links

Media related to Bass Strait at Wikimedia Commons

• Tasmanian Department of State Development - Redi Map
• "Telstra plans second Bass Strait optical fibre cable". Sydney Morning Herald. 2 August 2002. 
• "The Basslink Project". National Grid. 
• "History of the Atlantic Cable & Undersea Communications". 

Further reading

• Broxam and Nash, Tasmanian Shipwrecks, Volumes I and II, Navarine Publishing, Canberra, 1998 & 2000.

List of Australian seas Ocean Indian Ocean Pacific Ocean Southern Ocean Sea Arafura Sea Coral Sea Tasman Sea Timor Sea Strait Backstairs Passage Bass Strait Clarence Strait Dundas Strait Endeavour Strait Investigator Strait Torres Strait Gulf Beagle Gulf Cambridge Gulf Gulf of Carpentaria Great Australian Bight Exmouth Gulf Joseph Bonaparte Gulf Gulf St Vincent Spencer Gulf Van Diemen Gulf

Coordinates: 40°S 146°E / 40°S 146°E / -40; 146