House Martin ( Delichon urbicum )

This morning I was out in the garden doing a "!Big Butterfly Count" and intending to blip another species.  The House Martins were in and out of the nest, I assume feeding newly hatched young.  I decided to try for a shot of them instead.

They were in and out far too quickly for a shot of the whole birds so I got this one of an adult preparing to leave.  Sadly Martins are doing very badly, there has been a there has been a 37% decrease in numbers over the last 40 or 50 years.  There are many possible reasons, they now arrive 16 days earlier this may not coincide with food supplies.  Climate change and food supplies in their winter habitat.  It is even possible that House Sparrows taking over nests may be having a detrimental affect.