Montgomery Reef is a reef off the Kimberley coast of Western Australia. It is situated at the southwestern Camden Sound  end of and surrounds Yawajaba (Montgomery) Island. With its total area of 400 square kilometers (154 sq mi) it is the world's largest inshore reef. The reef and island were named by Philip Parker King, the first European to sight the island, aboard the HMS Mermaid while exploring the area in 1818. King named the island after the ship's surgeon, Andrew Montgomery.  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 4 meters (13 ft) 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. 

EXPEDITION SHORE EXCURSION:

Zodiac Cruise

Arriving on high tide, we leave the ship and head out by Zodiac to the edge of  Montgomery reef. As soon as the tide drops it exposes the “river” a narrow channel we will explore by Zodiac. We will witness torrent water and endless cascading waterfalls. As the water drops further, the reef is exposed, and fish are trapped on the reef and in pools. They brings in an array of birdlife. Keep a look out for the white and grey morph eastern reef egret, ospreys, white bellied sea eagles and the beach thick knee. In the water we hope to see dugongs, stokes sea snake, tawny nurse sharks and hammerhead sharks. When the tide is out, many turtles are concentrated into the 'river', and over a few hours one can see dozens and dozens of them. They are often found both in the water and stranded on the reef.