19a. Chatham Rise
Map ID Number: 19a
Location: A submarine extension of the New Zealand Plateau that extends eastward of the South Island for 1400km.
Approximate area: 248,955 km2
Description of area:
The Chatham Rise occurs underneath the Subtropical Convergence, a major oceanic front with high surface productivity. It is a classic mixing zone of north and south biogeographic elements. The crest of the rise is of geologic interest. It is a locality for nodules of the mineral phosphorite, as well as areas of glauconite. The crest is the northernmost settling ground for iceberg-rafted rocks from Antarctica.
Biological attributes:
The Chatham Rise is the southern limit in New Zealand for stony sponges (“lithistids”). There are thickets of stony corals on the crest of the rise. Seamounts found on the Rise have variably diverse assemblages of deepsea biota.
Criteria applied:
Species diversity and richness; trophic functional diversity; aggregations; meeting ground.
Status and management:
The Chatham Rise supports commercial fisheries for a considerable number of species, each of which is controlled by the Quota Management System. Six seamounts are closed to trawling on the Chatham Rise.
State of information:
The rise has been the focus of considerable research focus by NIWA and other research providers.
References and further reading:
Dawson (1984), Haywood et al. (2002), Nodder et al. (2003), Probert et al. (1996), Probert and McKnight (1993, 1997), Probert et al. (1997), Rowden et al. (2002).