Dr Robert Keirle of the Marine Conservation Society says the wet summer of 2012 is partly to blame for a decline in some Welsh bathing beaches.
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The pair met after Sheeran's concert for food at Park House restaurant in Cardiff.
An absolute sizzler of a week to come with blue skies and sunshine for all, with temperatures rising!
Tributes have been paid to a 39-year-old Welsh man who was killed in a suspected deliberate hit-and-run in Cyrus.