Recherche Archipelago

Recherche Archipelago

Location of the Recherché Archipelago

View of the Recherche Archipelago from Dempster Head

A drawing from the Westall collection with the title "Middle Island, view north to Cape Arid".

Recherche Archipelago is a group of 105 islands, and over 1200 "obstacles to shipping", off the south coast of Western Australia. The islands stretch 230 km (140 mi) from East to West and to 50 km (31 mi) off-shore encompassing an area of approximately 4,000 square kilometres (1,544 sq mi).^[1] The western group is near Esperance and the eastern group at Israelite Bay. They are located in coastal and inland waters, part of which is designated the Recherche Archipelago Nature Reserve.

History

View of the Recherche Archipelago from Lucky Bay, Cape Le Grand National Park

Pre-European

Indigenous Australians are thought to have inhabited some of the islands up to 18,000 years ago. Archeologists have found ancient artefacts on Salisbury Island such as stone blades, lizard traps, axe heads, grinding stones and granite watering holes. The objects are believed to be 5,000 to 18,000 years old from a time when many of the islands were joined to the mainland.^[2]

European discovery and naming

The islands became known to Europeans when François Thijssen and Pieter Nuyts, sailing on Gulden Zeepaert, sighted and explored the area in 1627. George Vancouver also passed through the archipelago as part of his expedition in HMS Discovery in 1791.^[3] The area was named the Recherche Archipelago (French: L’Archipel de la Recherche, IPA: [aʁ.ʃi.pɛl də la ʁə.ʃɛʁʃ]) by Bruni d'Entrecasteaux during a French expedition in 1792. This name was taken from one of the rear admiral's ships, La Recherche; the town of Esperance is named from the other ship of the expedition. They also came to be known as the D'Entrecasteaux Islands. Matthew Flinders was the first to explore and chart the islands of the archipelago in 1802 as part of his voyage in the Investigator.^[4]

Maritime history

Flinders ditched two anchors when leaving Middle Island in 1803. These were found and recovered in 1973 by divers.^[5] The best bower anchor is on display at the South Australian Maritime Museum while the stream anchor can be seen at the National Museum of Australia.^[6][7][8]

Sealers and whalers from other British colonies on the Australian continent frequented the area since at least the early 1820s.^[9]

The brig Belinda was wrecked off Middle Island while sealing in late 1824, the crew all made it safely to shore and were picked up the Nereus shortly afyerward and taken back to Sydney. The schooner Liberty salvaged the wreck the following year collecting metal stores and both the anchors.^[10]

Australia's only recorded pirate, Black Jack Anderson, frequented the archipelago in the 1830s. A former whaler, he turned to piracy and wreaked havoc in the area until being murdered by his crew.^[11] Middle Island was regarded as the right whale station of the bight in the 1830s and 1840s.^[9]

The Mountaineer was sunk off Thistle Cove near Cape Le Grand in 1835 while attempting to find shelter from a gale.^[12] The Rodondo was thought to be wrecked on Polloch Reef off Salisbury Island in 1895.^[12]

The SS Penguin was wrecked in 1920 off Middle Island while trying to shelter from a gale. The vessel was salvaged later the following year.^[13]

On 14 February 1991 the Sanko Harvest a bulk carrier of 33,024 tons sank in the archipelago – and it became the second largest wreck that can be dived on in the world.^[14][15] The response to pollution caused by the wreck was reported upon soon after^[16]

Uses of the area now include recreational and commercial fishing, and shipping from the Port of Esperance.

Commercial fishing is primarily for abalone, southern rock lobsters, pilchards, and sharks, and fishing tourism is an established industry. The area is proposed for other applications of aquaculture, including farming trials of bluefin tuna.^[17]

Geography

The archipelago includes 105 features classed as islands, and more than 1500 islets.^[4][18] The islands of the archipelago have a combined area of 9,720 hectares (24,019 acres).^[19] The islands are generally composed of granite outcrops, often with steep slopes and usually lacking beaches. A large number of features are submerged, some becoming exposed by tides. The coast is subject to some of the most extreme wave energy in all of Australia, with the wave energy causing abrasion as far down as 100 metres (328 ft) during storms. The inner shelf of the archipelago has an average depth of 40 metres (131 ft) with most of the islands being in 60 metres (197 ft) of water.^[20]

Groups

The islands are usually considered as being either in the western group, near Esperance and Woody Island and Cape Le Grand National Park, or in the eastern group where Middle Island is most prominent, near Cape Arid National Park^[21] Some surveys of the archipelago go further than the eastern and western distinction and consider groupings around named islands.^[22]

Part of the area is included in the bioregion described as Esperance 2 (ESP2), the 'Recherche subregion', which contains Cape Le Grand National Park at its western end, and the Cape Arid National Park at the eastern end. This area is named the Recherche Archipelago Nature Reserve.

Islands

Flora and fauna

The area is a biodiversity hotspot with high biodiversity and a large number of species that are native to the region.^[36] The environment contains a diverse array of subtropical and temperate flora and fauna. This is partly due to the Leeuwin current that flows in an easterly direction, this warms the cold seas to over 20 °C (68 °F) in summer.^[20] Larger islands have a substrate that supports vegetation, nesting birds, and other animals. A complex marine environment is found in the surrounding waters, the benthic habitat is various densities of seagrass meadows, reefs, or bare sand.

Marine

The waters around the islands meet often steep faces of granite, the extensive reefs and other features form habitat which supports a rich diversity of marine life. This includes 263 known species of fish, 347 known species of mollusc,^[36] and over 450 types of sponge, sea grasses, and soft corals. A coral-like algae species, rhodoliths, form beds which support marine species of spiders, snails, and worms, also acting as a creche for scallops.^[37] Marine mammals associated with the islands include two species of seal, large groups of common dolphins (Delphinus delphis), and minke whales (Balaenoptera acutorostrata).

Seagrasses found at the island include: Amphibolis antarctica, Amphibolis griffithii, Halophila decipiens, Halophila ovalis, Posidonia angustifolia, Posidonia australis, Posidonia coriacea, Posidonia denhartogii, Posidonia kirkmani, Posidonia ostenfeldii, Posidonia sinuosa, Syringodium isoetifolium, and Thalassodendron pachyrhizum.^[38]

Terrestrial

The islands support populations of terrestrial flora and fauna, some of which are unique to the archipelago. New Zealand fur seal (Arctocephalus forsteri) and Australian sea-lion (Neophoca cinerea) breeding colonies are found on some islands, with haul-out sites on many. Marsupials include tammars (Macropus eugenii derbianus), a species of bandicoot (Isoodon obesulus), two subspecies of rock wallabies (Petrogale lateralis lateralis and Petrogale lateralis hacketti). Snakes include the Recherche Island dugite (Pseudonaja affinis tanneri) on Cull Island, and the python Morelia spilota imbricata. Other reptiles include the barking gecko (Underwoodisaurus milii), ornate dragon (Ctenophorus ornatus), and the southern heath monitor (Varanus rosenbergi). Two species of frog are also found on the islands; the quacking frog Crinia georgiana and spotted-thighed frog Litoria cyclorhyncha.:^[39]

Many of the animals and plants are in refugia, where they are remote from factors that threaten mainland populations.^[18]

Birds

The archipelago has been identified by BirdLife International as an Important Bird Area (IBA) because it is the only breeding site for the western subspecies of Cape Barren goose known as the Recherche Cape Barren goose. It also supports over 1% of the world populations of flesh-footed shearwaters, sooty oystercatchers, fairy terns and, probably, white-faced storm-petrels. Rock parrots and red-eared firetails have also been recorded.^[40]

References

Further reading

• Australian Geographical Society (1952–1954). Expedition to the Recherché Archipelago, Western Australia. Australian Geographical Society reports. no.1 (7 reports in 4 volumes)
  • pt. 1a. General history by J.M. Bechervaise—pt. 1b. Physiography by R.W. Fairbridge and V.N. Serventy—pt. 2. Birds by V.N. Serventy—pt. 3. Plants, 3a. Land flora by J.H. Willis, 3b. Marine algae by H.B.S. Womersley—pt. 4. Mammals by V. N. Serventy—pt. 5. Reptiles and frogs by L. Glauert—pt. 6. Spiders and opiliones by Barbara York Main—pt. 7. Molluscs (sea shells and snails) by J. Hope Macpherson.
• Kendrick, G. (et al.) (2005) Characterising the fish habitats of the Recherche Archipelago Crawley, W.A. University of Western Australia. Fisheries Research and Development Corporation. ISBN 1-74052-122-6 "Fisheries Research and Development Corporation report, project no. 2001/060."
• Thomson-Dans, Carolyn, Kendrick, Gary and Bancroft, Kevin (2003) Researching the Recherche.Landscope (Como, W.A), Winter 2003, p. 6–8,

Early cartography

• Beautemps-Beaupré, C. F. (1807) Carte de l'archipel de la Recherche, situé à la partie occidentale de la terre de Nuyts, reconnu par le contre amiral Bruny-Dentrecasteaux, en décembre 1792 (an 1er de l'ere Française) Paris : Dépôt général des cartes et plans de la marine et des colonies], Battye Library Map Stack B/23/17 Scale [ca. 1:436,000] (Map of Recherche Archipelago showing track of Recherche and Espérance in December 1792). (Battye copy reduced to approximately 1:812,000 and 25 x 38.4 cm)

External links

• Geoscience Australia – location details
• 2002 Research project announced
• Map of the region