in their efforts to maximise fitness while reducing the probability of dying, animals must trade off food for safety. the trade-off is likely to depend on habitat and habitat change. i imagine an environment with both safe and risky (manipulated) patches in which foragers can respond by altering their pattern of foraging, by avoidance, or by reduced activity. analytical models predict that if foragers exploit risky patches, predation risk will either increase with distance from safety, or with the area foraged. but if foragers avoid risky patches, predation risk will either decelerate or decline sigmoidally with area away from the risky patch.