Fig. 2

Breeding-season kernel density home ranges for yellow-legged gulls on Frioul, Marseille, France, 2021 (Y1; a) oiled, n = 14; b) non-oiled, n = 13) – 2022 (Y2; c) oiled n = 13, d) non-oiled, n = 7). Darker polygons show the cumulative footprint of all individual 50% contour areas, and lighter colors show 90% contours. Yellow stars indicate the breeding colony location. The interaction of year with oiling status was a significant predictor of both 50% and 90% contour areas (see Table 1)