Vicinity of sparrowhawk nest affects willow tit nest defense

Female willow tits reduce their defense intensity directly in proportion to the closeness of their nests to the nearest sparrowhawk nest. It is clear in terms of spatial arrangement that tits breeding close to sparrowhawk nests face hawks more regularly than tits breeding further away. The distinct nature of the responses to the sparrowhawk nest distance was corroborated by the control experiment. There is no dependency on hawk-nest distance in responses towards stoats.