The Site lies within the Al Wusta Wetlands Reserve and covers about 80% of the Reserve’s area. It features coastal waters with rare marine vegetation, alkaline lakes and marshes, coral and bivalve reefs, mangroves, and “sabkha”, which are intertidal flats with mineral deposits formed by seawater evaporation. The Barr Al Hikman peninsula occupies the largest area of the Site and has a coastline of about 160 kilometres. The Site is highly biodiverse and hosts about 80 threatened species and several endemic plants and animals, including the spurge Euphorbia riebeckii, the Omani spiny-tailed lizard (Uromastyx thomasi), the green sawfish (Pristis zijsron) and the spotted guitarfish (Rhinobatos punctifer). About 24% of the endangered Arabian Sea subpopulation of humpback whale (Megaptera novaeangliae) are found in the Site. It also shelters more than 1% of the biogeographical population of 23 bird species, and some 465,000 individual waterbirds are present here annually. The coastal waters of Barr Al Hikman have extensive seagrass beds, mangroves and reefs that provide critical habitat for about 40 fish species including sharks and rays. The only prawn fishery in the country is also situated in this area.