Bass Strait
sea strait between the Australian mainland and Tasmania
Bass Strait is a strait separating the island state of Tasmania from the Australian mainland (more specifically the coast of Victoria, with the exception of the land border across Boundary Islet). The strait provides the most direct waterway between the Great Australian Bight and the Tasman Sea, and is also the only maritime route into the economically prominent Port Phillip Bay.
Formed 8,000 years ago by rising sea levels at the end of the last glacial period, the strait was named after English explorer and physician George Bass (1771–1803) by European colonists.
Extent
The International Hydrographic Organization defines the limits of Bass Strait as follows:
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].
Differing views of location and context
Some authorities consider the strait to be part of the Pacific Ocean as in the never-approved 2002 IHO Limits of Oceans and Seas draft. In the currently in-force IHO 1953 draft, it is instead associated with the Great Australian Bight; the Bight is numbered 62, while the Bass Strait is designated 62-A.
The Australian Hydrographic Service does not consider it to be part of its expanded definition of the Southern Ocean, but rather states that it lies with the Tasman Sea. The strait between the Furneaux Islands and Tasmania is Banks Strait, a subdivision of Bass Strait.
“Bass Strait” enters the record as sea strait between the Australian mainland and Tasmania. Crown Archives preserves that source wording while asking what Bass, Strait and strait can confirm, complicate or overturn.
Why this record matters
“Bass Strait” is worth following because a concise public description often conceals a longer documentary argument. Here, Bass, Strait and strait provides the most credible route into that argument.
The strongest evidence will usually combine a dated visual record with documents produced by the authority responsible for the place. The source revision retrieved here is dated Sep 21, 2026. The linked authority identifier is Q171846. VIAF identifies the subject as 245820782. The Library of Congress control number is sh88001473. Authority coordinates are -40.000, 146.000. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1771, 1803, 2002 and 1953.
Modern boundaries and familiar names can conceal earlier jurisdictions or structures that do not align with the present site. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Bass Strait”, its source revision and the description used here.
- Expand the search: follow Bass Strait primary sources, Bass Strait archive and Bass research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Bass Strait”?
- What physical evidence or contemporary plan supports the description?
- Which earlier names or jurisdictions may reveal additional records?
Search terms from this dossier
This entry incorporates text from “Bass Strait” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.