Table 1. Summary of the numbers of colour-ringed adult shags known to have bred on the Isle of May that were resighted during winters 2009–2012 across all survey sites. ¹ .

	Winter
	2009–2010	2010–2011	2011–2012	Grand total
Total positive survey days	88	107	118	313
Median (IQR) positive survey days per month	13 (11–14)	14 (13–17)	20 (14–22)
Median (IQR) positive survey sites per month	8 (7–11)	11 (10–14)	14 (11–15)
Total resightings	700	1488	1609	3797
Total individuals resighted	317	575	605	882
Total individuals resighted on ≥2 dates	146	350	342	561
Median (IQR) resightings per individual resighted on ≥2 dates within a single winter	3 (2–4)	3 (2–4)	3 (2–4)
Median (IQR) days between consecutive resightings of an individual resighted on ≥2 dates	16 (7–38)	18 (7–54)	12 (5–31)
Median (IQR) days between first and last resightings of an individual resighted on >2 dates	73 (30–128)	106 (49–137)	76 (45–114)

¹Grand totals are of unique individuals resighted across all winters, so do not equal the sum of individuals resighted within individual winters. Interquartile ranges (IQR) are shown in parentheses. Positive survey days are days on which at least one colour-ringed shag was resighted (Figure S1). Positive survey sites are roosts separated by ≥1 km where at least one colour-ringed shag was resighted on ≥1 date (Figure 1).