On 1 July 2025, NIWA merged with GNS Science to become Earth Sciences New Zealand.

Grass carp enclosure - vegetation density in high stocking density enclosure after 7 weeks

The story underwater - 7 weeks after grass carp were released into the enclosures. The vegetation in the enclosures with highest stocking densities (eg., 4 and 5) is opening out, not as dense. Credit: John Clayton