Montgomery Reef
{{Short description|Reef in the Kimberley region of Western Australia}}
{{Use Australian English|date=December 2018}}
{{Use dmy dates|date=December 2018}}
{{Infobox islands
| name = Montgomery Reef
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| image_name = Montgomery Reef.jpg
| image_size = 222px
| image_caption = Montgomery Reef on a late autumn afternoon.
| image_alt = Image of Montgomery Reef.
| image_map = {{Infobox mapframe
|id = Q6905773
|frame-width=222
|frame-height=222
|frame-lat=-15.993333
|frame-long=124.239722
|marker-colour=#1F2F57
|zoom=2
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| map_alt = Map showing location of Montgomery Reef.
| map_size =
| map_caption = Montgomery Reef is off the Kimberley coast of Western Australia.
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| coordinates = {{coord
|15|59|36|S|124|14|23|E
|display=inline,title
|region:AU_type:isle_source:GNS-enwiki
|name=Montgomery Reef
}}
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| location = Indian Ocean
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| country = {{flag|Australia|name=Commonwealth of Australia}}
| country_admin_divisions_title = State
| country_admin_divisions = Western Australia
| country_admin_divisions_title_1 = Reef
| country_admin_divisions_1 = Montgomery Reef
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| timezone1 = AWST
| utc_offset1 = +8
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Montgomery Reef is a reef off the Kimberley coast of Western Australia. It is situated at the south western end of Camden Sound and surrounds Yawajaba (Montgomery) Island. With its total area of {{convert|400|km2|sqmi|0}} (about {{convert|80|km|mi|0}} in length),{{cite web|url=http://www.cruiseaway.com.au/cruise-port/montgomery-reef-western-australia|title=Cruiseaway - Kimberley Cruises|year=2011|accessdate=2012-04-24}} it is the world's largest inshore reef.{{cite web | title=Camden Sound | website=Western Australia | url=https://www.westernaustralia.com/en/Attraction/Camden_Sound/5a027e183e472af476cad03e | access-date=3 January 2021}} The nearest populated place is Bardi, which is approximately {{convert|130|km|mi|0}} to the south west.{{cite web|url=http://maps.bonzle.com/c/a?a=p&p=15258&cmd=sp|title= Bonzle Encyclopedia - Montgomery Islands|year=2009|accessdate=2012-04-24}}
The reef lies approximately {{convert|20|km|mi|0}} off shore, opposite Doubtful Bay to the east and Collier Bay to the south.{{cite web|url=http://www.kimberleycoast.com.au/Icons/Montgomery/|title=The Kimberley Coast - Montgomery Reef|year=2011|accessdate=2012-04-24}} It lies within the Camden Sound Marine Park, which was gazetted in 2012, covering an area of {{convert|7062|km2|sqmi|0}}.{{cite web|url=http://www.dec.wa.gov.au/content/view/5665/2297/|title=Department of Environment - Camden Sound Marine Park|year=2012|accessdate=24 April 2012|archive-url=https://web.archive.org/web/20120420211829/http://www.dec.wa.gov.au/content/view/5665/2297#|archive-date=20 April 2012|url-status=dead|df=dmy-all}}
The reef and island were named by Philip Parker King, the first European to sight the island, aboard {{HMS|Mermaid|1817|6}}, while exploring the area in 1818. King named the island after the ship's surgeon, Andrew Montgomery.{{cite web|url=http://www.australiaforeveryone.com.au/wonders_montgomery.htm|title=Australia for Everyone - Kimberley wonders|year=2011|accessdate=2012-04-24}} King also named Doubtful Bay.{{cite web | title=Doubtful Bay - Kimberley Region, North West Australia | website=The Great Escape Charter Company | url=https://greatescapecruises.com.au/location/doubtful-bay/ | access-date=1 January 2021}}
Montgomery Reef has an unusual wide tidal range, up to {{convert|10|m|ft|0}}. When the tide is out, vast lagoons, sandstone islets, and a central mangrove 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 {{convert|4|m|ft|0}} of reef can be exposed.
While the tide is going out, the waterfalls attract migratory wading birds, feeding turtles, manta rays, black tipped reef sharks, and dugongs. The area is a popular tourist site and has several cruise operators visiting daily.{{cite web|url=http://kimberleycruise.com.au/kimberley-region/kimberley-map/|title=Kimberley Cruises|year=2011|accessdate=2012-04-25}}