Latest Science Helps Trout Anglers

The result of 10 years of research into trout habits and environments by scientists at New Zealand's Cawthron Institute has revealed new information that will help anglers worldwide in their quest to understand their quarry.

The research covers four broad areas - how land-use and flow change affect trout fisheries, the effects of increasing anglers on trout rivers, trout feeding behaviour, and the distribution and movements of trout.

World expert on trout, Cawthron's Dr John Hayes, co-authored the book "The Artful Science of Trout Fishing" (published by Canterbury University Press) with renowned angler and photographer Les Hill. The book combines the latest scientific knowledge on trout with practical applications for anglers.

"I'm a keen trout angler myself, so I wanted to turn the interesting science we've been doing at Cawthron to practical use. It's cutting edge and highly technical science that's been made easy to understand in the book and of great relevance to anglers," says Dr Hayes.

Cawthron's Freshwater Group, working with colleagues from the University of Alaska, and Bureau of Land Management, Fairbanks, has revealed previously unknown details of how trout feed in rivers through a programme of research funded largely by the NZ Government's Foundation for Research, Science and Technology and also by Fish and Game New Zealand. Using underwater video cameras to monitor individual trout, they have been able to devise a computer model which shows how trout feed on insects drifting with a river's flow. Versions of the same model can be used to predict how fast trout will grow and how many trout a river reach can support.

Their research is also revealing how poor land management is impacting on trout rivers. Dr Hayes says: "Trout are one of the most sensitive biological indicators in freshwater - if things aren't right in the rivers, trout size and numbers are the first to decline - and anglers are the first to complain. The Freshwater Group has examined all sorts of biological impacts on rivers, such as temperature, flow change, and pollution, and the results have made clients and the public much more aware of their effects on fragile freshwater ecosystems. "

Dr Hayes believes this is the first book of its kind in the world to provide such a comprehensive overview of the science underpinning trout fisheries and trout fishing - from descriptions of trout senses and behaviour to angling tips on how to protect our trout fisheries for the future.

"While it's set in New Zealand and gives local examples, this is really applicable to trout fishing, management, and conservation worldwide. And I hope it makes trout anglers start to think about how we can ensure the trout are still there for future generations to enjoy" says Dr Hayes.

Media Release, 2 March 2005

For more information contact: Dr John Hayes or the Canterbury University Press.

Relevant Links:

Nelson Mail story

Cawthron's trout research at the Motupiko River