Trout count and stream health survey underway

Trout need clean water to survive so are a good indicator of stream health.

Fish & Game staff are jumping in the water to check the trout population and assess the health of the country’s waterways.

Equipped with diving gear, staff will drift and glide down hundreds of kilometres of rivers across the country, recording water clarity and temperature, assess fish habitat, the number of native fish, algal growth and the insects that are there.

Divers will explore more than 250km of waterways, covering about 100 different rivers around the country.

The information from the trout population surveys will be used to help set catch limits for anglers.

Fish & Game New Zealand chief executive Corina Jordan said the programme highlighted the important environmental monitoring role of the organisation.

“Drift diving enables us to give rivers a close-up health check. Combined with our assessment of the trout population - the species that has the highest water quality requirement of any of New Zealand’s fish - these observations will give us a good gauge on how healthy our rivers are.

“It is going to be interesting to see how the North Island rivers in particular have fared after Cyclone Gabrielle.”

Many regions have information dating back over 30 years which could give valuable insight into the long-term trends of river health.

“It will give us unique insights into the interactions between trout and some of our native fish, such as eels, which co-exist quite happily.

“In fact, it’s not uncommon for divers to see trout being eaten by eels, or trout with bite marks on them, which shows trout have become an important component of the food chain in many New Zealand rivers.”

The drift dive programme is expected to run until early April.

Fish & Game is a non-profit organisation that receives no Government or taxpayer money, it is funded solely from the purchase of licences to fish for trout and salmon and hunt game birds.