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Industrial valleys pose new threats for returning birdlife

For decades the valleys of south Wales were known for their coalmines and slag heaps. But in recent years there have been reports of a flourishing wildlife.

Scientists from Cardiff University have been analysing the eggs of wild songbirds which have started nesting in the area.

Hywel Griffith explains why it is not all good news.

  • 03 Aug 2013
  • From the section Wales