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Fig. 2 | Movement Ecology

Fig. 2

From: Seasonal and inter-annual  variation  in exposure to peregrines (Falco peregrinus) for southbound western sandpipers (Calidris mauri)

Fig. 2

Annual progression of the exposure index (relative number of peregrines sighted daily) on the Fraser estuary, in years with varying peregrine arrival date (x-axis; m in Eq. 1). Peregrine arrival is defined as the date that 50% of the October level in that year is reached, with dots indicating the arrival dates observed in this study. The logistic curves used here are based on Fig. 1, shifted left or right to represent years with earlier or later peregrine arrival, respectively. Three examples are shown (orange: m = 200; grey: m = 220; black: m = 240). The mean passage dates for adult western sandpipers (day-of-year 198) and juveniles (day-of-year 228) are indicated by vertical lines

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Movement Ecology

ISSN: 2051-3933