I've just finished coverage of four woodcock survey sites with results as follows. Values are numbers of sightings of one or more woodcocks from fixed locations over 75 minutes on three dusk visits during May-June. The equivalent survey in 2003 (data in brackets) involved counts over 60 minutes. The longer count period in 2013 did make a difference although the last (extra) quarter hour tended to have fewer passes than the earlier ones.
Crowle Moors visit 1 - 0 (5 including one of 2 birds) visit 2 - 1 (0) visit 3 - 0 (0) NB the 2013 count was at a different location from that which I counted in 2003, and I don't have 2003 data for this year's location.
Laughton Forest (W) visit 1 - 11 including one of 4 birds (8) visit 2 - 7 (13) visit 3 - 11 (11)
Laughton Forest (E) visit 1 - 5 (4) visit 2 - 5 (4) visit 3 - 4 (6)
Stonepit Wood visit 1 - 15 (11) visit 2 - 10 (10 including two of 2 birds) visit 3 - 17 including two of 2 birds (6 including one of 2 birds)
So for these areas, woodcock abundance seems little changed since 2003 except possibly at Crowle, where the changed location may have affected results – and also there has been much birch clearance.
All of the birds I recorded appeared to be roding males except for the gang of four at Laughton, which I took to be three males chasing a female.
GCT has devised a formula that converts numbers of sightings recorded in this way to population density (based on distinguishing individual males using sound recordings). As I understand it, the numbers of males in my four areas works out at 1, 4, 2 and 5-6. The estimate of roding males in Britain in 2003, by the way, was 78,350.
Any other results anywhere?
Andrew
Full details will be sent to Colin & Sheila as well as to BTO
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