A plethora of corals in the southern Pacific
In the New Zealand region there are abundant and diverse cold-water corals, found on seamounts, slopes, on ridges and in canyons. They have been reasonably well-studied with records going back as far as the 1830s. At present 1,126 cnidarian species (the group including corals and anemones) have been recorded in New Zealand, of which 330 are still unidentified and/or undescribed. There are also 204 fossil species.
New Zealand boasts both warm-water corals with symbiotic algae (zooxanthellae) and cold-water corals growing in the darker depths. For example, in the north of New Zealand’s Exclusive Economic Zone (EEZ) around Raoul Island warm-water corals reach their southern limit while along the adjacent Kermadec Ridge cold-water corals thrive at greater depths.
Further south in the dark waters of Fiordland, on the southwest coast of the South Island, the black coral Antipathella fiordensis grows at depths of only 15 to 50 m. The stylasterid hydrocoral Errina is also found in the sounds of Fiordland. In waters deeper than 200 m scleractinian stony corals, both solitary cup corals and the matrix-forming stony corals occur. While there are no records of Lophelia in the New Zealand region, another member of the same family (Caryophllyidae), Solenosmilia variabilis, is abundant. Other species include Madrepora oculata, Goniocorella dumosa - the most dominant branching stony coral, Enallopsammia rostrata and E. marenzelleri, and Oculina virgosa which is found nowhere else (endemic). Apart from O. virgosa, all are found throughout the region mainly between water depths of approximately 200–1500 m.
Even further south, The New Zealand Ross Sea Protectorate in Antarctic waters supports a diverse coral fauna with recent research surveys and observer bycatch data revealing the presence of cup corals (but no reef-forming species), Errina, and several gorgonian octocorals including Corallidae (precious coral), Isididae (bamboo corals), Primnoidae (sea fans), and Paragorgidae (bubblegum corals).