Sleuths lose tasty trout

An ecologist is mystified by the disappearance of 18 brown trout fitted with transmitters, and fears the majority of them have ended up on dinner tables.

As part of a study on trout movement in the Motueka River and its tributaries, the Cawthron Institute installed transmitters in 50 brown trout in the Motupiko River in October.

Five months later, despite signs along the river asking for transmitter-wearing trout to be released, 18 fish are missing.

Ecologist Roger Young said "it was a bit of a mystery" why so many had vanished off the radar.

It was unlikely the transmitters had failed, or that the fish had swum out of the area. The most likely explanation was that more than a few transmitters had "ended up in someone's fridge", he said.

The institute conducted an aerial sweep of the Motupiko and Motueka rivers last week but only one of the missing trout was found. Dr Young said people with the $300 transmitters should hand them in.

The research will continue until October, despite the depleted stocks. Results so far show the trout have stayed unexpectedly close to home.

- NZPA