The nestcam suggested the four chicks on Nest 1A were in good condition. Examination by the licensed ringer, the Kielder ornithologist, and weighing the chicks showed the camera did not lie! We found more evidence of YA’s abilities as a provider, and Mrs YA’s determination to distribute food equally because none of their offspring showed any sign of “fault bars”. These are the feather markings that would have indicated periods of restricted growth when the chicks were younger.
Chick 1 is now Blue Y0 and weighed 1730 grams. She was assessed as female.
She was very interested in proceedings!
When it came to applying the glue to seal the Darvic colour ring she took a bite out of the tube! Back in her nest she showed off her new colour ring.
Chick 2 was next to be assessed. He weighed 1430 grams, a reasonable weight for a male. He wears Darvic ring Blue Y1.
He also posed happily when back ‘home’.
Chick 3, also thought to be male, weighed 1500 grams. He is now known as Blue Y2. He was not keen to pose!
Finally chick 4, who looks quite small on the nestcam, weighed in at 1700 grams. Yes, 1700, it was double checked! At this stage of their development more of the energy contained in food goes into feather production and less into skeletal mass. Because of this any visual judgement of chick size has to be confirmed by careful weighing and measuring.
Chick 4, a female, is now Blue Y3.
Even more up close!
Many thanks to Paul Wildlifewriter for technical assistance and input to the draft.