Population modelling

Hoki is New Zealand's largest finfish fishery. During this voyage, hoki eggs reveal a few secrets that surprise scientists.

NIWA researchers are out on the Hauraki Gulf this week to find out more about the nurseries of young snapper.

NIWA has developed a new method for spatially-explicit, quantitative, sustainability risk assessment of pelagic shark population.

Sharks are vulnerable to overfishing because of their low reproductive rates and often low growth rates. Most pelagic sharks fall near the middle of the shark productivity scale, and there is concern that catching too many of them could lead to population depletion. In New Zealand waters, mako sharks are the second most commonly caught shark species (after blue sharks) on tuna longlines.

CASAL is an advanced software package developed by NIWA for fish stock assessment.

NIWA expends considerable effort on determining the age of commercial fish species. But why age a fish? And how do we do it?

To get the most benefit from a fish stock in the long term, we need to maximise our yield without damaging the fish population we rely on.

Casal2 is an advanced software package developed by NIWA for modelling the population dynamics of marine species.