No.20 2008

Know your beach with Coastal Explorer

No-fish zone protects life on the seabed

Where do baby oysters go?

Tangaroa upgrades undersea currents technology

New Zealand Regional Bathymetry Chart

Where do baby oysters go?

Where do baby oysters go?

The aim: more of these – a premium Nelson oyster. (Photo: Stephen Brown, NIWA)

Modelling the dispersal of oyster larvae, to predict distribution of newly settled larvae or ‘spat’, in Tasman Bay, is a new challenge for NIWA scientists.

No-fish zone protects life on the seabed

No-fish zone protects life on the seabed

Grab samples showing the amount of biomass from the fished zone (left), and the protected zone (right). (Photo: Sean Handley, NIWA).

Seabed communities at Separation Point, Nelson, have been left more-or-less untouched since 1980, when the area was closed to power fishing. NIWA scientists studying the communities have found clear evidence of the benefits of that protection.
The area, between Tasman and Golden Bays, was closed to protect various species of bottom-dwelling (benthic) bryozoans living on the soft seafloor sediment.

Tangaroa upgrades undersea currents technology

Tangaroa upgrades undersea currents technology

Tangaroa during dry dock. (Photo: Brett Grant, NIWA)

Display of current speed through Cook Strait region as measured by the new ADCP.

The recent Tangaroa dry-dock at Devonport Naval Base in Auckland provided the ideal opportunity to install a new Acoustic Doppler Current Profiler (ADCP) - one of the most important tools on NIWA’s iconic research vessel.
ADCPs provide three dimensional current data from beneath the ship by measuring the frequencyshift (or Doppler shift) in echoes reflected from free-floating particles or plankton.

Research subject: Oceans