Anglers are being asked to help in the search for a rare fish that appears to be getting more common on the rivers of North Wales.
Every June thousands of shad spawn in Wales but mostly in three rivers in the south of the country – the Wye, Usk and Tywi.
In contrast to salmon and sea trout, shad populations seem to be doing well in Wales, unlike the rest of the UK and Europe, where numbers are falling.
Natural Resources Wales (NRW) is now hoping to get a more accurate picture of the fish’s distribution in Wales – especially in northern rivers.
Tristan Hatton-Ellis, NRW’s freshwater ecosystems team leader, said: “Like the swallow, shads are a sign of summer on the rivers.
“We are interested in shad records from anywhere in Wales but particularly from rivers in North Wales where we think there may be small populations.
“In the past we had assumed that rivers in North Wales were unsuitable for shad but new information suggests this may have been incorrect.
“It’s also possible climate change is opening up new rivers for shad, as they like warm water.”
There are two species of shad – the allis shad and twaite shad – and they are the only members of the herring family found in UK fresh waters.
In the past they went by other names such as the May Fish, King of the Herring and the Bony Horseman.
Shad were once widely fished. In the Severn Estuary during 19th century, they made up about one third of all catches, their value rivalling salmon.
Tristan urged anglers to keep their eyes peeled. “Look out for them at dusk in the middle to lower reaches of rivers, where you can see them circling one another,” he said.
“Later in the night, they spawn with a lot of noisy splashing as the males chase the females.”
Shad spend most of their lives at sea – they can live for 10 years – but in early summer they move to rivers to spawn.
After laying thousands of eggs to start the next generation, many of them die.
Tristan added: “River or sea anglers sometimes catch them by accident, and you may also come across carcasses of fish that have either died naturally or been caught by otters.
“If you do catch a shad, please take a photograph before carefully returning it to the river, minimizing handling as they are more delicate than many other fish.”
Source : DailyPost