The Biology Refugia: Who's at risk during stopovers - the heavy or light bird?:
It seems that the risk of being heavy due to fuel loads with respect to reduced escape performance is overestimated. The higher exposure of light birds due to more intense foraging and displacement to suboptimal habitats is probably of higher biological significance by offering conspicuous prey for predators.
The lower risk of heavy birds when prey of different body condition is available for predators has implications for modelling optimal migration behaviour, and predation risk is perhaps not an important factor for migrants when deciding on site use.
Evolved strategies, testable evolutionary hypotheses.