Montgomery Reef is a

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...

off the Kimberley coast of

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

. It is situated at the south western end of

Camden Sound Camden Sound is a relatively wide body of water in the Indian Ocean located in the Kimberley region of Western Australia. The Sound is bounded by the Bonaparte Archipelago to the north-east, the Buccaneer Archipelago to the south-west, and M ...

and surrounds Yawajaba (Montgomery) Island. With its total area of (about in length), it is the world's largest inshore reef. The nearest populated place is Bardi, which is approximately to the south west. The reef lies approximately off shore, opposite Doubtful Bay to the east and Collier Bay to the south. It lies within the Camden Sound Marine Park, which was gazetted in 2012, covering an area of . The reef and island were named by

Philip Parker King Rear Admiral Phillip Parker King, FRS, RN (13 December 1791 – 26 February 1856) was an early explorer of the Australian and Patagonian coasts. Early life and education King was born on Norfolk Island, to Philip Gidley King and Anna Jos ...

, the first European to sight the island, aboard , while exploring the area in 1818. King named the island after the ship's surgeon, Andrew Montgomery. King also named Doubtful Bay. Montgomery Reef has an unusual wide

tidal range Tidal range is the difference in height between high tide and low tide. Tides are the rise and fall of sea levels caused by gravitational forces exerted by the Moon and Sun and the rotation of Earth. Tidal range depends on time and location. ...

, up to . When the tide is out, vast lagoons,

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

islets, and a central

mangrove A mangrove is a shrub or tree that grows in coastal saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evolution in severa ...

island are revealed. The outward movement of the tide forms a torrent of water, creating a river cutting through the reef and hundreds of cascading waterfalls. At low tide, more than of reef can be exposed. While the tide is going out, the waterfalls attract migratory wading birds, feeding

turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked t ...

s, manta rays, black tipped reef sharks, and

dugong The dugong (; ''Dugong dugon'') is a marine mammal. It is one of four living species of the order Sirenia, which also includes three species of manatees. It is the only living representative of the once-diverse family Dugongidae; its closest m ...

s. The area is a popular tourist site and has several cruise operators visiting daily.

References

{{commons category-inline Islands of the Kimberley (Western Australia)