Ecology of geothermal vegetation and habitats at the Waimangu Rotomahana geothermal site, Rotorua

Abstract

The Waimangu-Rotomahana geothermal area is part of the Waikite-Waiotapu-Waimangu Geothermal System (WWWGS) which is located in the Taupo Volcanic Zone, which extends across the Bay of Plenty and Waikato Regions. WWWGS is a protected geothermal system. The Waimangu-Rotomahana geothermal area includes the Waimangu Geothermal Valley, and the margins and cliffs of Lake Rotomahana. The Waimangu Geothermal Valley is considered to be one of the youngest geothermal areas in Aotearoa New Zealand, and all current geothermal vegetation has developed since the Tarawera eruption in 1886. Despite its young age, the area contains some of the most important populations of the special plants and habitats present within the geothermal areas of the Taupo Volcanic Zone. Geothermal vegetation is of high ecological significance, and almost all the geothermal vegetation within the area is in good condition. However, there are ongoing pressures from pest plants and pest animals which threaten ecological integrity. This paper presents information on important plants and fauna at the Waimangu-Rotomahana geothermal field (including Threatened and At Risk species), endangered ecosystem types, ecological pressures, and management requirements. A brief ecological history and a summary of geothermal vegetation and habitats present at other sites in this geothermal field is presented.