How to PIT-tag a salmon parr

Our state of the art research facilities on the River Frome include electronics that enable us to record the migration history of individual fish. Each September, since 2005, we have fitted 10,000 salmon parr with Passive Integrated Transponder (PIT) tags that transmit an individual barcode when a fish swims past one of our antennae.

Approximately 10% of the Frome salmon population is fitted with PIT tags, helping to make the River Frome salmon population one of the most comprehensively studied in Europe.

This is how we tag the salmon:

1. The parr are caught by electro-fishing. Two teams work on the river for three weeks until 10,000 parr have been tagged. An average of 400 parr are tagged each day per team.

2. The fish is anaesthetised and the length and weight are recorded. Scales are collected and are used to look at growth rate, age and to determine sex.

3. A small insertion is made with a scalpel and a PIT tag is inserted into the body cavity where it will remain for the lifetime of the salmon.

4. The fish is transferred to a holding tank to recover before being released into the 100-metre section where it was caught.

Our salmon work

We're conducting vital research into what is causing the decline in salmon numbers with the ultimate goal of reversing that decline...

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