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...

Click here to find out more >

Salmonids in the floods

You may have noticed we're experiencing a bit of wet weather at the moment in the UK with flooding heaping misery on people across the country.

Flooding on the River Avon at GWCT HQ in January 2014

Whilst the effects of flooding on humans are all too obvious, we are not the only species to be affected by floods. Fish inhabit the very rivers that are bursting their banks onto the surrounding towns and countryside. Unlike humans, however, fish have been experiencing floods in their native river habitats for hundreds or thousands of years. And because floods present a strong evolutionarily selective force (you adapt or you die), fish have adapted to survive and even thrive under certain flood conditions.

Salmonids are a good example of a group of fish species that have adapted to local flow regimes...

Read full article on our website >

New Presentation: Wylye Grayling Long-Term Study

Stephen Gregory of the GWCT recently gave a talk at the Avon Piscatorial Society annual Fly Day meeting in Salisbury. The topic of the talk was grayling on the Wylye river in Hampshire and how the population might be affected by flooding, past and future.

You can view the slides from the presentation here:

View Piscatorial Society Fly Day Grayling Talk Feb14 and other presentations by sgregory.

Electro-fishing workshop for MorFish project

The GWCT's Bill Beaumont recently delivered a keynote speech at a workshop on electro-fishing sampling methods and theory.

The talk formed part of the information exchange process with the French team who are working with us on the MorFish project. A group of 40 INRA and Onema staff attended the meeting.

Find out more about electro-fishing here >

New Presentation: Salmon Research at the River Frome

The slides below are taken from a recent presentation covering the salmon research that the GWCT are currently conducting on the River Frome. The presentation took place at West Stafford Village Hall and was given to the Dorset Chalk Stream Club on the 20th December:

You can find out more about the Dorset Chalk Stream Club here and there are photos from the talk on John Aplin's blog.

Presentation: Adult salmon monitoring on the Frome

Stephen Gregory from our fisheries team recently delivered a presentation about adult salmon monitoring on the Frome during his time spent with INRA Rennes in France. You can see the slides here:

New Photos from the GWCT Salmon & Trout Research Centre

Three of our newest members of staff visited our Research Centre at East Stoke on the River Frome this morning and took a few pictures:

The counting station on the Frome where adult salmon are recorded.

Senior Fisheries Scientist William Beaumont demonstrates some of the equipment used to monitor fish.

A pipe from the compressor used to create the bubble curtain that helps separate large and small fish for monitoring purposes.