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Less positively still sign of Spot Fly at either location, after what turned out to be a transient sighting in Fernyness Wood on 23 May last year, and at the Saw Mill on 30 May the previous year; before that my last local (NT47) bird was Seton Dean 8 June 2004, several repeat visits in intervening years failed to refind. Very scarce, probably still diminishing, in these parts (widespread losses, particularly in Lothian, since last atlas: change map).
In Edinburgh, Swift still at Nigel Loan, Liberton - "confirmed" after a stake-out, flying in with bulging throat (pouch containing bolus, example photo) at about 20 minute intervals, leaving cavity again after several minutes inside. Actually rather naive about Swift parenting behaviour and was not sure when I would expect it to emerge! The first one entering I never saw emerge until a second entered twenty minutes later; one bird emerged 6.5 mins after that - may actually have been first. Nothing in BWP on visit duration, but found an illuminating paper* which includes a graph showing average visit duration (in minutes) as function of chick age (in days), 83 (1-5), 32 (6-10), 13 (11-15), 6 (16-20) and 4 (20-25). So, chicks of some sort in there for sure!
* Dell'Omo G., Alleva E., Carere C. (1998) Parental recycling of nestling faeces in the common swift Animal Behaviour, 56 (3), pp. 631-637.
Also Chiff and Goldcrest in song more frequently again at KB, presumably starting second brood.
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