10/2/2010

Salmon and other species of fish are making a dramatic comeback to the River Taff to spawn and ensure future populations.

That is the message from Environment Agency Wales who say it is due to the reduction of industrial pollution and their own improved regulation and network of fish passes,

And the Agency illustrates the improvements with the fishy tale of a skinny but determined fish they have monitored and given the name of Salmon 66, who through his adventures on the Taff has shown that no matter what the obstacles, salmon are resilient and ambitious, especially when it comes to affairs of the heart.

The Agency Wales traps and monitors fish every year and Salmin 66 had already clocked up any miles before being trapped at Radyr Weir (today an obstruction to migratory fish but in the nineteenth century essential to the operation of a local tin plate works).

He had found his way past the award winning Cardiff Bay Barrage and two other significant weirs. At Radyr, Environment Agency Wales stepped in and fitted him with a radio tag to monitor his progress up the Taff.

The tracking programme provides detailed information on fish movement, which allows the Agency to assess the impact of redundant weirs from the time of the Industrial Revolution on fish migrations, and the effectiveness of the new network of fish passes.

Environment Agency Wales, through this monitoring, can sometimes also learn a lot about the behaviour of individual fish.

Salmon 66 was tracked to an area called Upper Boat before using a fish pass at the otherwise insurmountable Treforest Weir.

He then moved on to Pontypridd, twelve miles north of Cardiff and ‘the gateway to the South Wales Valleys’ before arriving at the rural village of Troedyrhiw.

The journey took him approximately two months to complete, and exhausted by his travels he took a well earned rest in a deep pool near Troedyrhiw, before moving up the river again towards the spawning grounds. Such movement is not uncommon amongssalmon but Salmon 66 is no ordinary salmon.

66 then dared to go where no fish has gone before, Environment Agency Wales’s Merthyr Weir, a £450,000 fish pass opened in 2008.

Perhaps spurred on by his achievements, he travelled on to the Cefn Coed Weir but rather earlier than expected he started his return journey, descending five major weirs to arrive back downstream at Blackweir, the Agency’s newly completed fish pass, which was officially opened earlier this month by Welsh rugby legend Gareth Edwards.

Having covered a river distance of approximately 100 kilometres the Agency expected 66 to leave the river and head back out to sea, probably never to be seen or heard of again.

But 66 amazed Agency officers by reversing his course again, instead making his way back up the river, over the same three weirs he had negotiated twice before, to a relatively unknown stream known as the Nant Lonydd.

Two days later Agency monitoring revealed the salmon’s motivation for this strange behaviour. He had company, a similar sized salmon but a female, tagged as Salmon 111. They were found lying together on a shallow gravel bed.

The following day a salmon redd was present indicating that their spawning was complete.

Environment Agency Wales Technical Specialist Pete Gough said: “This story, whilst appropriate for Valentine’s Day, also provides a fascinating insight into the behaviour of salmon in the River Taff.

"Although it’s a great real-life story, it also tells us that the network of fish passes on the river is working well. Salmon 66 used the large fish pass on the Cardiff Bay Barrage to enter the Taff, and moved up and down the river freely.

"His migration shows that there is no significant delay below any of the major weirs, which we believe shows that the free migration of salmon in the River Taff is at last nearly restored.�

Sadly everlasting love this was not; Salmon 66 moved back to the Taff and again swam upstream whilst Salmon 111 was later seen in the company of an untagged salmon.