THE Cockney sparrow was once a much-loved Londoner who lived feather-by-jowl with humans and was a daily sight in the skies above Camden.

But in just 10 years the number of the small brown birds darting through our gardens has declined by 50 per cent – and they are under threat of disappearing altogether.

This shocking fact is partly the motivation for conservationists to plaster the borough this week in blue plaques – based on the Historic England markers which denote a house where someone notable lived.

These nature versions, however, highlight just how decimated Camden’s wildlife has become in recent years.

Ecologist Dr Jeff Waage is one of the people behind the scheme, which culminates in a March for Nature, taking place on Saturday, June 22.