Plastic pollution: Swans build nests of rubbish in Cardiff

The swans were seen in Cardiff Bay amongst debris

A pair of swans have been seen collecting plastic to build nests due to the amount of rubbish in the water where they live.

One person described the water in Cardiff Bay as a "soup of rubbish."

Cardiff Harbour Authority said it took cleaning "seriously" but was faced with debris from two of the city's biggest rivers.

Wildlife Trust Wales said plastic pollution was very dangerous and often fatal for birds looking to build nests.

Sam Ryall, a BBC employee who photographed the swans, said on Twitter: "Look at the soup of rubbish where a pair of swans are nesting in Cardiff Bay.

"The pen is literally gathering beak-fulls of plastic from a neglected dock and lining her nest with it.

"How can this be allowed to happen? This is shameful."

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Tim Birch from Wildlife Trusts Wales said: "When birds ingest small pieces of plastic it can inflame the digestive tract and, over time, this inflammation can cause internal scarring that can affect digestion, growth and, ultimately, survival."

Sam Ryall described the situation in Cardiff Bay as "shameful"

The Cardiff Harbour Authority, which is responsible for 48 miles (30km) of riverbank, said it "cleans to the highest possible standard within its resource capability" with a purpose-built litter boom on the River Taff designed to collect the majority of the debris.

However, it added: "The rivers are not static and there are two vast river catchment areas that feed the bay. As a result, we are faced with a conveyor of debris entering our area of responsibility.

"Over the past 20 years we have collected an average of 500 tonnes of litter and debris each year."