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Supplementary information on breeding sites for barn swallows around Kraghede, Denmark, with name of breeding site, latitude (o N), longitude (o E), date of first leafing of elm (1 = 1 April), date of first flowering of snowdrop (1 = 1 February), mean laying date for barn swallow (1 = 1 May), variance in laying date for barn swallow, mean colony size (number of pairs), and proportion of time that a site was occupied. See Material and methods for further details.

Site / Latitude / Longitude / Date elm leafing (1 = 1 April) / Date snowdrop flowering (1 = 1 February) / Mean laying date (1 = 1 May) / Variance in laying date / Mean colony size (no.pairs) / Proportion of time site occupied
Åen / 57o12'40'' / 10 o00'39'' / 30 / 28 / 40.27 / 128.78 / 7.9 / 0.200
Birkholt / 57 o12'41'' / 9 o59'31'' / 28 / 24 / 27.03 / 60.37 / 1.4 / 0.588
Britta / 57 o13'30'' / 10 o05'09'' / 37 / 29 / 43.00 / 75.00 / 0.3 / 0.208
Bukgård / 57 o12'22'' / 9 o59'48'' / 27 / 25 / 22.00 / 172.66 / 0.7 / 0.667
Edward / 57 o12'06'' / 10 o01'59'' / 29 / 27 / 34.03 / 159.01 / 14.2 / 1.000
Engbæk / 57 o12'45'' / 9 o52'35'' / 29 / 31 / 30.13 / 174.24 / 10.0 / 1.000
Engholt / 57 o12'50'' / 9 o59'57'' / 32 / 29 / 35.31 / 155.25 / 8.4 / 0.579
Gammel Nejst / 57 o13'00'' / 9 o58'06'' / 28 / 23 / 35.10 / 141.13 / 13.6 / 1.000
Grindstedgård / 57 o17'01'' / 9 o58'44'' / 29 / 22 / 32.10 / 174.24 / 19.1 / 1.000
Hvilshøj / 57 o13'24'' / 10 o02'20'' / 28 / 25 / 34.50 / 24.50 / 0.6 / 0.583
Inger / 57 o13'33'' / 10 o05'15'' / 33 / 32 / 40.50 / 44.50 / 0.1 / 0.111
Iver / 57 o15'12'' / 10 o01'14'' / 30 / 31 / 37.44 / 180.90 / 0.3 / 0.118
Kaj / 57 o12'09'' / 10 o01'14'' / 30 / 29 / 25.43 / 105.27 / 4.1 / 1.000
Krabdrup / 57 o12'10'' / 10 o01'16'' / 30 / 28 / 32.17 / 66.59 / 0.6 / 0.312
Kraghede Mølle / 57 o12'41'' / 9 o58'31'' / 27 / 28 / 34.96 / 108.58 / 5.3 / 1.000
Laden / 57 o13'49'' / 10 o05'51'' / 34 / 32 / 52.50 / 243.05 / 0.0 / 0.042
Lene / 57 o12'18'' / 10. o00'35'' / 35 / 28 / 37.17 / 151.54 / 0.4 / 0.417
Lilholt / 57 o12'30'' / 9 o59'31'' / 29 / 25 / 29.43 / 144.24 / 6.6 / 1.000
Lille Nejst / 57 o13'00'' / 9 o58'40'' / 26 / 26 / 27.13 / 84.46 / 0.7 / 0.292
Marinus / 57 o12'11'' / 10 o01'59'' / 30 / 28 / 33.30 / 171.87 / 3.2 / 1.000
Missionshus / 57 o12'18'' / 10 o00'30'' / 39 / 34 / 59.00 / . / 0.0 / 0.042
Niels Zachariasen / 57 o12'18'' / 10 o00'01'' / 30 / 27 / 32.69 / 242.74 / 2.5 / 1.000
Nikolaj / 57 o15'12'' / 10 o01'17'' / 28 / 25 / 35.60 / 202.49 / 1.2 / 0.294
Nørregård / 57 o16'00'' / 10 o01'05'' / 25 / 27 / 34.76 / 147.14 / 3.8 / 0.500
Ny Nejst / 57 o12'52'' / 9 o57'46'' / 35 / 29 / 50.56 / 629.51 / 0.2 / 0.091
Øster Gjerndrup / 57 o14'10'' / 10 o01'34'' / 29 / 28 / 33.48 / 87.42 / 12.3 / 0.647
Østergård / 57 o12'25'' / 10 o01'50'' / 32 / 28 / 35.00 / 299.98 / 0.3 / 0.273
Ryå / 57 o12'44'' / 10 o01'42'' / . / . / 40.00 / . / 0.2 / 0.167
Ryå Kraghede / 57 o11'58'' / 10 o02'50'' / . / . / 41.82 / 167.19 / 0.5 / 0.545
Ryå Ørum / 57 o12'07'' / 10 o04'51'' / . / . / 39.75 / 38.32 / 0.1 / 0.056
Ryå Vildmose / 57 o14'24'' / 9 o54'03'' / . / . / 71.00 / . / 0.0 / 0.042
Rygård / 57 o15'35'' / 9 o51'39'' / 32 / 30 / 36.01 / 156.75 / 33.2 / 1.000
Skur Åensvej / 57 o12'55'' / 10 o01'51'' / . / . / 45.60 / 37.82 / 0.1 / 0.083
Skur Kraghede / 57 o12'10'' / 10 o01'51'' / . / . / 59.43 / 356.45 / 0.3 / 0.250
Søren Krog / 57 o12'27'' / 10 o01'27'' / 31 / 25 / 31.45 / 91.87 / 5.2 / 1.000
Stenisholt / 57 o13'14'' / 9 o56'10'' / 30 / 32 / 36.66 / 48.86 / 7.8 / 0.500
Vadbæk / 57 o13'45'' / 10 o05'45'' / . / . / 31.17 / 95.84 / 0.2 / 0.208
Vestergård / 57 o11'45'' / 10 o06'23'' / 25 / 27 / 33.24 / 166.41 / 9.9 / 0.667
Vittenberggård / 57 o11'53'' / 10 o01'05'' / 27 / 22 / 38.93 / 242.64 / 5.0 / 0.286