Thursday, 9 July 2015

Sparrowhawks

I have found this year pretty poor for nest recording. Not only have I struggled to find many nests most of the ones I have found have failed at some point. Therefore I was particularly pleased that this Sparrowhawk nest was successful (well almost!).

The nest was found on 27/05/2015 and contained 5 warm eggs, these were still there on the 09/06/2015.

I hoped I could plan my next visit right and there would be chicks which were big enough to ring. This is particularly important with sparrowhawks due to the different ring sizes for the sexes, it also prevents too many visits, minimising any disturbance.

A visit on the 26/06/2015 resulted in 4 chicks and an addled egg. The age of the chicks allowed them to be sexed and the appropriate ring fitted. All the chicks were equally developed with yellowish legs, approx. 10 mm of primary feather, a few mm of tail feather showing and a few contour feathers just becoming visible. There were 2 males weighing 110 and 125 grams and 2 females weighing 165 and 170 grams. The average weights for adult sparrowhawks are 150 grams for males and 260 grams for females.

Further discrete visits from a distance on 04/07/15 and 08/07/2015 showed all the chicks looking well and standing on the nest. I apologise for the poor “digiscope” photo taken on the 08/07, it was the best view I could get.

I may carry out one more discreet visit in a few days before submitting the nest record which will make a valuable contribution to the 60 or so submitted to the BTO each year.

Mick P





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