Brett on top of the silo, next to the box with a kestrel seen high in the sky to the left of the box.The top of a concrete silo alongside one of Europe's busiest motorways is not everyone's ideal home, but these industrial chic surroundings are heaven to a family of kestrels.

Brett Erwin, a plant supervisor working for Lafarge [supplying concrete to the Highways Agency project, widening the M25 at junction 29] first saw and recognised the birds. Calling upon schoolboy memories and experience of a previous job in forestry, he knocked up a wooden nest box and sought his employers permission to fix it to the concrete silo.

The birds moved in and promply laid six eggs, which have now all hatched successfully. Brett bought a £20 webcam so he and colleagues could watch the nest from their site cabin when not working; and it's kept them all entranced. "I was really excited when I saw the kestrels using the box", said Brett. "Once the nesting season's over, we'll move the box to a nearby tree so they've got a home when our silo's removed."

Work's nearing completion, on time for the increased traffic expected around east London for the 2012 Olympics.

The site's closed to the public and drivers are warned not to look out for the birds hovering alongside the motorway while driving. You can see kestrels at our Rainham Marsh nature reserve just a junction down (come off at J30 and head towards the A13 to London, come off at the next junction for Purfleet) from the widening works.

The nesting kestrels haven't interfered with work on the widening or on site, but it's a great example of a major contruction project working with nature.

Kestrels eat small mammals, bugs and occassionally other birds. The nest is close to a series of water ditches and fields, and Brett told me their webcam footage shows their main diet is mice and voles.

Kestrels are small falcons and if you're in London anytime from 16 July through to 11 September, we'll have powerful telescopes available to see peregrine falcons at the Tate Modern on the southbank. Our trailer will be next to the Millennium footbridge from Noon until 7 pm every day.

Anonymous