1. Kermadec Ridge
Map ID Number: 1
Location: Northeastern New Zealand
Approximate area: 661,885km2
Description of area:
The Kermadec Islands are geographically isolated from New Zealand and other subtropical and tropical islands that may serve as source areas for planktonic larvae. The area is characterised by steep rocky islets and seamounts. The Kermadec Ridge connects the deeper waters of the New Zealand mainland with tropical waters to the north. The neighbouring Kermadec Trench is the deepest region in New Zealand's Exclusive Economic Zone, and one of the deepest in the world.
Biological attributes:
The Kermadec Ridge has a diverse fish fauna that includes several endemic species. The area is isolated from mainland New Zealand waters by the Tropical Convergence and there are biogeographic affinities with Norfolk Island and the Lord Howe Rise, with a large subtropical species component not found elsewhere in New Zealand. The Kermadec Islands are home to the world's largest population of spotted black grouper (Epinephelus daemelii), which is a protected species.
Criteria applied:
Species richness; endemism; representation; conservation status/threat classification both nationally and globally; extremities of range and adaptation to environment; special phylogenetic grouping; habitat complexity/ diversity; meeting ground - overlap between biological regions (at national and global regions level); links to global patterns.
Status and management:
Spotted black grouper are vulnerable to exploitation because of their longevity and large size (up to 2 m), their sex-changing population dynamics, their existence in shallow water (to 50 m), and their territorial behaviour. They are protected by the Wildlife Act (1953). The waters around all the Kermadec Islands are protected by a marine reserve. The reserve extends out to 12 nautical miles and encompasses an area of 7,450km2.
State of information:
The ?-mark on Area 1 (Kermadec Ridge) indicates uncertainty in placement of this boundary due to insufficient sampling to determine how far along the ridge the distinctive elements of the fauna extend. This boundary fluctuates with the seasonal movement of the convergence zone. Basic knowledge exists of the fauna, but the ecology is virtually unstudied.
References and further reading:
Cole (2001), Cole et al. (1992), Francis (1993, 1996, 2001), Francis et al. (1987).