If you do one thing this week ... (try to) spot an otter

These elusive creatures are back from the brink of extinction in Britain, but that's no guarantee you'll get to see one. Still, it's worth a try

It is a quiet, calm dawn and the low sun silvers the surface of the river. Ahead, a line of bubbles on the water. We stop paddling and our canoe glides silently downstream. Suddenly we are spotted: two greylag geese honk noisily. Whatever was bubbling in the water ahead of us - an otter? - slips away, unseen.

When I was a boy, you were about as likely to see an otter in the wild as a big cat. Otter-spotting was an exotic pursuit only worth attempting on a trip to the Highlands. Over the last two decades, however, helped by the banning of pesticides that once washed into our rivers, European otters (Lutra Lutra) have returned to every English county. They are also seen on urban waterways - in Manchester, Bristol, Birmingham and even on the Thames and the Lea around London.