Kermadecs Corals and Bryozoans

Kermadecs Corals and Bryozoans

The Kermadec bryozoan fauna includes 256 species of these tiny colonial animals which build stony skeletons similar to corals. The group is characterised by high species diversity, and by a large number of endemic species and genera. At present, 56 species have not been identified precisely and many of these will be new to science. There are 38 endemic species and four endemic genera.

Among the Kermadec bryozoan fauna are several species of ‘living fossils’. Onychoblestrum hastingsae and Reginella vas have been present in the Earth’s oceans from the Late Eocene to the present day ), a period of some 39 million years. Quadricellaria bocki and Marssonopora kermadecensis, which also occur along the Kermadec Arc, are living representatives of genera that first appeared in the Late Cretaceous at the time of the dinosaurs.

In recent years, scientific expeditions have collected samples and images of deep-water corals from the Kermadec Arc area, along with samples of deep-water fishes, squids, octopuses and other invertebrates. These are currently being analysed by scientists and others. Among the deep-water corals, a sample from the large bubblegum coral Sibogagorgia tautahi was collected by NIWA scientists at Giggenbach seamount on the Kermadec Arc in April 2002. This species, known from only one specimen, is considered to be endemic to the Kermadec region[1]. Bamboo coral and black coral are also present in the Kermadec region, with the former recorded as bycatch in longline fishing operations in the region in recent times[2].

Also found at the Kermadecs are New Zealand’s only subtropical hard corals. Unlike in the tropics these corals do not form classic reefs given the cooler waters. Soft corals make up part of the shallow water benthic communities, contributing a variety of colours and structures to the Kermadecs underwater environment.

Photo: Tom Hitchon

[1] Sanchez 2005

[2] Griggs & Francis 2009