Few studies of animal escape behaviour simultaneously investigate behavioural and physiological responses. Differences between these response types, however, have consequences for the way in which habituation or tolerance is interpreted - behavioural habituation may incur physiological costs. We simultaneously measured heart rate (HR) and behavioural responses during standardised approaches to incubating Masked Lapwings Vanellus miles, an urban-frequenting ground-nesting bird. We describe the existence of a distinct Physiological-Initiation Distance (PID) that precedes Flight-Initiation Distance (FID) but does not necessarily precede Alert Distance (AD). Two distinct response types occurred: 'startle', where a behavioural or physiological response coincided with the appearance of a person (always the investigator; 75.9 % of 58 birds) and 'non-startle' responses, where a behavioural or physiological response occurred after the appearance of, and commencement of the approach by, the person (24.1 % or 14 birds). For birds which were not startled, the interval between the initial heart rate increase and heart rate peak increased with clutch age. For birds which were startled, longer durations of post-peak HR elevation were associated with shorter FIDs and older clutches. Thus, reduced FIDs (generally interpreted as a sign of habituation or tolerance) are associated with greater physiological costs through longer durations of elevated HR. Additionally, the existence of, often long and undetectable, PIDs suggests: 1) that behavioural measures of response underestimate responses in general, and 2) that the methodological assumption when collecting FIDs, that starting distances exceed response distances, may often be incorrect yet are visually undetectable. Further studies of a variety of taxa are warranted to determine the associations between behavioural and physiological responses, and should these associations prove reliable, they would ideally generate general predictions of PID from readily measurable behavioural metrics (FID or AD), thus enabling prescriptions to manage the consequences of human interactions with wildlife.

中文翻译：

---

行为容忍的生理代价

很少有关于动物逃逸行为的研究同时调查行为和生理反应。然而，这些反应类型之间的差异会对习惯或耐受的解释方式产生影响——行为习惯可能会导致生理成本。我们在孵化 Masked Lapwings Vanellus 英里（一种经常在城市地面筑巢的鸟类）的标准化方法中同时测量了心率 (HR) 和行为反应。我们描述了存在于飞行起始距离 (FID) 之前但不一定在警报距离 (AD) 之前的独特生理起始距离 (PID)。出现了两种不同的反应类型：“惊吓”，即行为或生理反应与人的外表一致（总是调查员；75。9 % 的 58 只鸟）和“非惊吓”反应，其中行为或生理反应发生在人出现并开始接近之后（24.1 % 或 14 只鸟）。对于没有受到惊吓的鸟类，初始心率增加和心率峰值之间的间隔随着离合器年龄的增加而增加。对于受到惊吓的鸟类，峰值后 HR 升高持续时间较长与较短的 FID 和较旧的离合器有关。因此，减少的 FID（通常被解释为习惯或耐受的标志）与更高的生理成本相关，因为 HR 持续时间更长。此外，通常很长且无法检测的 PID 的存在表明：1) 反应的行为测量总体上低估了反应，以及 2) 收集 FID 时的方法论假设，起始距离超过响应距离，通常可能是不正确的，但在视觉上无法检测到。需要对各种分类群进行进一步研究，以确定行为和生理反应之间的关联，如果这些关联被证明是可靠的，那么理想情况下，它们将根据易于测量的行为指标（FID 或 AD）生成对 PID 的一般预测，从而使处方能够管理人类与野生动物互动的后果。