Christmas Island Marine Park extends from the island’s shoreline to the limit of Australia’s Exclusive Economic Zone (AEEZ), approximately 200 nautical miles from shore. The marine park adjoins the marine boundary of Christmas Island National Park.

The tropical waters and fringing coral reefs that surround Christmas Island contain a mix of coral reef species from both the Indian and Pacific Oceans and over 680 species of fish. The overlap of these waters gives rise to varieties of hybrid marine fish and endemic species that are found nowhere else on earth. Christmas Island also has the world’s greatest diversity and abundance of land crabs, most notably its famous red crab. The island’s waters are essential for the crabs as they migrate to the coast to breed and release their eggs into the ocean. Other important inshore marine habitats include cave systems which support a mix of distinct species.

The offshore waters and habitats of Christmas Island Marine Park are relatively poorly studied, but are known to contain a range of unique seafloor features, habitats and species, particularly seamounts and deep-sea plains. Other biologically importnt areas include foraging areas for the endemic Abbott’s Booby, Christmas Island Frigatebird and Golden bosun and other seabirds that nest on Christmas Island, as well as whale shark feeding areas and southern bluefish tuna breeding habitat. The marine park also protects species like dolphins, deep sea fish and sharks that are or may be threatened elsewhere in the region.

The park covers an area of 277,016 square kilometres. Its offshore waters are a National Park Zone where extractive activities are not allowed, while its inshore waters are a Habitat Protection Zone where fishing is permitted, but activities that disturb the seafloor are not. – Parks Australia

Christmas Island ranges from the high tide mark to more than 6,000 metres depth, with an average depth of 5,038 metres. The majority of the park (90%) falls within the abyssal zone (4,000-6,000 metres). [View on map] The mapped areas of the seafloor are dominated by Plane (68%) and Slope (20%) geomorphology. [View on map]