Parent birds assess nest predation risk: influence of cavity condition and avian nest predator activity

摘要: Skutch (1949) hypothesized that nest predators visually assess parental activities to locate a prey nest, whereas parents modify fitness-related traits reduce the probability of predation. We examined how cavity condition and activity interact with avian shape success two coexisting parid species, marsh tits (Poecile palustris) oriental (Parus minor), breeding in nest-boxes during incubation period. Nest-boxes were manipulated create prolonged risk predation (entrance diameter 2.6 cm control vs. 5.5 treatment) soon after clutch completion. To measure changes behavior, we also simultaneously simulated pulsed predation, using sound playbacks bird an predator. found parent merely responded risk, presumably due environment high predator encounters, compared risk. Instead, both species spent more time on vigilance at only under conditions. The corvids near nest-box was higher tit than tits. This treatment box nest-box. Nest period tits, plastic Our results highlight differences nests non-excavators may contribute differential by attracting predators. This article is protected copyright. All rights reserved.