Why time-limited individuals can make populations more vulnerable to disturbance

Individual variation in disturbance vulnerability (i.e. the likelihood that disturbance negatively affects an individual’s fitness) can affect how disturbance impacts animal populations, as even at low disturbance levels some individuals could be severely affected and die. Individual variation in vulnerability can arise due to different responses to disturbance. We propose a new hypothesis that even when individuals respond similarly to disturbance, time-limited individuals are more at risk that their condition deteriorates since they have limited ability to extend their foraging time to compensate for disturbance. We investigate this ‘time-limitation hypothesis’ both empirically and mathematically by studying how individuals that differ in their average foraging time (presumably due to differences in foraging efficiency) are affected by disturbance. We used tracking data of 22 wintering Eurasian oystercatchers Haematopus ostralegus to compare time budgets between disturbed and undistur...

干扰脆弱性（即干扰对个体适合度产生负面影响的可能性）的个体差异，会影响干扰对动物种群的作用效果——即使在低干扰水平下，部分个体仍可能受到严重影响甚至死亡。个体脆弱性的差异可源于对干扰的不同响应模式。本研究提出一项新假说：即使个体对干扰的响应方式相似，受时间限制的个体其身体状况恶化的风险更高，因为它们无法通过延长觅食时长来弥补干扰带来的损失。我们通过探究平均觅食时长存在差异（推测源于觅食效率差异）的个体受干扰的影响情况，从实证与数学建模两个维度对这一“时间限制假说”开展验证。本研究使用了22只越冬欧亚蛎鹬（Haematopus ostralegus）的追踪数据，对比受干扰与未受干扰个体的时间分配……