Despite AB and A4 putting in regular appearances recently, its becoming more difficult to re-sight our blackbirds simply because there are fewer blackbirds about! Only two blackbirds (including A4!) were seen during a walk around most of the study area yesterday.
The detectability of blackbirds (as can be seen from the BirdTrack graph below) declines as the summer progresses. At this time of year the birds begin to go through their annual moult; a time when they renew their plumage an the birds tend to skulk in the undergrowth, keeping themselves to themselves. Although this behaviour reduces their vulnerability to predation it of course makes them harder to see!
Reporting rates of blackbirds reported to BirdTrack show the seasonal change in the 'detectability' of the species.
The blue line shows the reporting rate for 2013 and the red line shows the average reporting rate for all previous years.