Animals switch between inactive and active states, simultaneously impacting their energy intake, energy expenditure and predation risk, and collectively defining how they engage with environmental variation and trophic interactions. We assess daily activity responses to long‐term variation in temperature, resources and mating opportunities to examine whether individuals choose to be active or inactive according to an optimisation of the relative energetic and reproductive gains each state offers. We show that this simplified behavioural decision approach predicts most activity variation (R² = 0.83) expressed by free‐ranging red squirrels over 4 years, as quantified through accelerometer recordings (489 deployments; 5066 squirrel‐days). Recognising activity as a determinant of energetic status, the predictability of activity variation aggregated at a daily scale, and the clear signal that behaviour is environmentally forced through optimisation of gain, provides an integrated approach to examine behavioural variation as an intermediary between environmental variation and energetic, life‐history and ecological outcomes.

中文翻译：

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精力和生殖能力的优化说明了不同季节和年份对环境变化的行为反应

动物在非活动状态和活动状态之间切换，同时影响它们的能量摄入，能量消耗和捕食风险，并共同定义它们如何与环境变化和营养相互作用相互作用。我们评估日常活动对温度，资源和交配机会的长期变化的反应，以根据每个州提供的相对能量和生殖收益的优化，检查个人是选择活跃还是不活跃。我们表明，这种简化的行为决策方法可以预测大多数活动变化（R ² = 0.83）表示为4年内自由放养的红松鼠，通过加速度计记录量化（489次部署； 5066次松鼠日）。认识到活动是精力充沛状态的决定因素，活动变化的可预测性在每日范围内汇总以及明确的信号表明行为是通过优化增益而在环境上强制执行的，这提供了一种综合的方法来检查行为变化，将其作为环境变化与精力充沛之间的中介，生活史和生态成果。