There were four nests visited that day. Professional tree climbers lower the chicks to the ground to be processed before returning them safely to the nest.
The Milkwellburn Wood, brood (Derwent Valley)
The chicks were processed at a field station set up near the nest site. They are weighed and their wings measured before fitting BTO leg rings and wing tags if they are large enough. The session went extremely well with four nests being visited. In total eleven chicks had leg rings fitted of which nine were big enough to wing tag. A really successful outcome.
This year's wing tag colours are pink on the left wing, which indicates that the bird fledged in the north east of England, and red for the right wing tag which is the year colour for 2021. The wing tags helps identify birds once they have left the nest. Subsequent observations help determine survival rates and where birds disperse..
The above photograph shows wing tag T5 after fledging. T5 is the chick in the centre of the brood of three photograph at the top of the page. .