Figure 3

Relationship between black-legged kittiwake use of glacier fronts as a function of the distance separating their colonies to a given front at two different scales; (a) regional scale; involving 5 colonies and 25 glacier fronts (effect of distance; estimate =  − 0.22, 95% CI =  − 0.26: − 0.18) and (b) fjord scale; involving 4 colonies and 6 glacier fronts (effect of distance; estimate =  − 0.16, 95% CI =  − 0.22: − 0.09). For the ease of representation, points represent individual males and females average use (circles: yellow = female; green = male) of glacier fronts. Solid curves and shaded areas are the regression line and associated 95% confidence interval (back-transformed) estimated from generalized linear mixed models, using the glacier front use as response variable, the distance, sex and colony as additive fixed predictors and the bird ID as random factor.