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Table 2 Significant results of binomial GLMMs from the best supported models showing in which ecological factors actual positions differ from random points generated within a 50 km buffer zone either side of the flying path. Specifically, the effects of NDVI, tree cover and elevation and their interactions with season were tested for the a) northern (latitude 16 N northwards) and b) southern (latitude 16 N southwards) parts of the trip. In the drier north (e.g. Sahara desert), the falcons used areas with higher NDVI compared to randomly generated points, avoiding higher elevations. In the more vegetated south, the preference for higher NDVI was not significant, tagged individuals occurred though (especially in spring), in areas with higher tree cover, and subsequently higher elevations (particularly in autumn) than what was available to them along their route corridors. Best supported models were selected based on lowest AICc values (Full list of candidate models and results from full model and models within ΔAICc < 4 in Additional file 1: Table S1 and S2)

From: Habitat availability influences migration speed, refueling patterns and seasonal flyways of a fly-and-forage migrant

VariableEstimateSEzP
a) North (N = 901) 
Intercept9.231.356.84< 0.001
NDVI (log)−3.070.39−7.80< 0.001
Elevation (log)0.520.173.04< 0.01
b) South (N = 2811) 
Intercept3.501.033.42< 0.001
Tree cover (log)−0.480.10−4.85< 0.001
Elevation (log)−0.340.12−2.92< 0.01
Tree cover (log): Season0.490.172.94< 0.01
Elevation (log): Season−0.170.06−2.88< 0.01