New Zealand Marine Environments Classification - Hauraki region

Biological data from the Hauraki Gulf is gathered to establish spatial correlations between ecological variables and physical variables used to generate the regional classification under the New Zealand Marine Environments Classification. The MEC includes coastal waters, continental shelf and deep ocean environments. Purpose: To develop and test the New Zealand Marine Environment Classification (MEC) system.

The MECHau database includes 13 biological variables: benthic epifauna dredge, benthic infauna grab, benthic infauna core, smaller zooplankton, larger zooplankton, salps, mesozooplankton, chlorophyll shallow, chlorophyll deep, phaeopigment shallow, phaeopigment deep. Data from the MFish trawl survey database and NIWA's AllSeaBio database is also available for testing the MEC in the Hauraki Gulf regions. Recently undertaken benthos sampling (undertaken by NIWA, DOC contract) using a combination of remote sensing via QTC Impact and ground-truthing via grab sampling will be used to further test the MEC when available. MEC contains 15 physical variable layers (maps showing the spatial patterns in physical variables) for the EEZ scale classification, and 20 physical variable layers for a regional scale classification. The 20 regional physical variable layers available for the Hauraki Gulf are: bathymetry, 95% wave height, mean wave height, 95% orbital velocity, maximum tidal current, direction of maximum tidal current, mean depth averaged salinity, mean freshwater fraction, sediment type including dominant and sub dominant, sub-dominant sediment type, dominant sediment type, mean SST, SST annual amplitude, SST annual phase, SST semi-annual amplitude, SST within-month standard deviation, seabed curvature, seabed planform curvature, seabed rate of change of slope.

Hauraki Gulf/Firth of Thames

NZMG E2725650 N6457517, 1:100,000, Area

Various

Various benthic and water column sampling procedures. All except one of the MECHau variables (epifanua dredge) have been measured quantitatively, and the zooplankton variables include both densities and biomasses Frequency of collection: Varying

Due to varying collection and processing methods and identification personnel, it is recommended that benthos data be aggregated to lower levels of taxonomic resolution. Gaps in collection: Various Data quality: Varying Attribute accuracy: Varying – adequate for developing the MEC. Completeness: Some data sets (e.g. salp and larger zooplankton) have high numbers and wide dispersal of sampling stations, together with consistent sampling methods and personnel, whereas other data sets are not as useful spatially.

reports, spreadsheets, maps Digital Format: MS Word, MS Excel, GIS (ArcView)

Marine habitat classification Identification of suitable sites for marine reserves

Contact NIWA (Bryce Cooper, Hamilton) Sensitivity/Confidentiality: Contact NIWA

Awaiting input of physical data to further test the MEC

It is envisaged that the regional physical variables list used for the MEC will be reduced once the physical variables that most correlate with biological pattern are identified.