The Kestrel in Ayrshire - annual report 2010

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Annual Report 2010

After one of severest winters on record the worries about a crash in the number of breeding pairs was unfounded. In fact one pair defied the elements by laying their first egg on 21 March in appalling weather. The pair in this territory which over the decades has a record for being the earliest site, were in excess of three weeks ahead of the rest of population. Territory occupation was back up to around what you would expect in a good vole year and all the indications were that food was abundant – high clutch sizes, signs of vole activity on the ground and the amount of vole prey seen at the nests.

Clutch sizes were high with three of six and twelve of five eggs recorded. All the laying dates apart from the early anomaly were between 14 and 26 April. The weather during April, May and June was near perfect, dry and sunny though July was very poor with consistent long spells of rain. Hatching rates were good and the pairs were very productive – see table below.

The 2010 breeding statistics are as follows :-

	2010	2009	2008	2007	2006

Number of territories checked	37	39	41	34	35
% occupation	73	49	73	59	72
Number of clutches known	15	10	18	12	16
Average clutch size	5.2	4.6	5.3	5.25	4.75
% of eggs which hatched	89	91	83	95	84
Number of results known	25	19	26	17	25
Average young per breeding pair	3.8	2.8	3.81	4	3.2
Average young per successful pair	4.4	3.4	4.3	5.15	3.8
Number of breeding attempts failed	3	4	3	3	4
% failed	12	21	11	17	16
% brood survival	89	90	96	93	98
Number of young ringed	34	23	46	44	46

Number of field days: 34

The breeding season was one of the longest as the first pair were noted in territory on 25 February, the first egg laid on 21 March and the last young seen near a nest site on 8 August. The latter pair had failed with a clutch of four then relaid six (a measure of the food availability) eventually rearing four. Of the three failures two were at the prelaying stage and the other was brood predated by goshawk.

Only one ringing recovery was received. A bird ringed on 19 June 2004 was recovered near Coylton on 5 May 2010, a distance of only 28 km from its natal site.

One new project this year was the mounting of a camera and digital recording equipment in a kestrel nest box which recorded the last three weeks of the pair’s nesting activities. The data will be analysed this winter. Funding for the project was generously given by the Scottish Ornithologist’s Club and the South Strathclyde Raptor Study Group. It is hoped to continue the work in 2011.