Coracle fishing is at risk due to river pollution and climate change, fishers in mid and west Wales have claimed.
Floating on a coracle and using nets to feel the bottom of the river by hand to catch fish on the Teifi and the river Tywi is a centuries old tradition.
But fisher Andrew Davies said he finds everything there from raw sewage and sanitary towels to toilet rolls.
The Welsh government said it had made “significant funding” available to improve river water quality.
Coracle fishing takes place in darkness, typically early in the morning so that fish cannot see the nets.
There are reports that the bottom of the river Teifi is covered in a brown slime.
Algae is a result of increasing phosphate levels in the river.
“Basically, it covers the whole bottom of the river, and it just multiplies,” said Mr Davies, chairman of the Carmarthen Coracler and Netsmen’s Society, who has been fishing on the Tywi for 34 years.
“Within a week all the stones are covered with these green algae.
“And because there’s no flow in the rivers it just stays there and takes all the oxygen out of the water.”
In 2020 Natural Resources Wales (NRW) announced a set of by-laws to protect fish such as salmon and sea trout, meaning that any salmon caught by rod and net fisheries must be released.
Net fishing licences have also increased in price over the years and the fishing term has been reduced to three months, from May to July.
The Welsh government said: “We fully support communities in the Teifi catchment and across Wales in their demands to stop pollution in Wales’ rivers.
“We have made significant funding available to improve river water quality in Wales.
“It’s vital we all work together – government, regulators, developers, farmers, water companies and communities – to reduce the pollution in our rivers.
“It is only by working collaboratively that we can tackle the risks and threats our rivers face.”