Seal birth captured on camera in industrial Teesside
1 August 2013 Last updated at 00:19 BST
Industrial Teesside is not the place you would expect to find a seal colony but a clean-up over the last few decades has brought back the seals after years of industrial pollution.
Before the 1930s there were around 1,000 seals at the nature reserve at Greatham Creek, but pollution from heavy industry drove them away.
There is now a healthy population of Common Seals and these are the only seals in Europe which have re-colonised.
Hannah Bayman visited the seal colony and was surprised to witness the birth of a pup, captured on camera for the first time in northern England.
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