ABSTRACT

The Asian koel (Eudynamys scolopacea) is a well-known brood parasitic bird that visits Pakistan every summer from India. This species produces at least five loud call types that are presumed to be used in territorial and mating behaviour. We noticed vocal differences among individuals in the wild and hypothesised that Asian koels produce individually distinct vocalizations. To test this, we recorded type 1 cooee calls, coe calls, type 1 coegh calls, type 2 coegh call and wurroo calls from 46 adult birds in the wild, and measured 15 different acoustic parameters, both spectral and temporal, for each vocalization type. We also measured the Potential of Individual Coding (PIC). Parameters having PIC values ≥1.1 were further analysed through stepwise cross-validated discriminant function analysis (DFA). The DFA accurately categorised 86.5% of the type 1 cooee calls, 95.7% of coe calls, 91.5% of the type 1 coegh calls, 82.2% of type 2 coegh calls and 83.3% of wurroo calls to the individuals from which these calls were recorded. Thus, consistent with our hypothesis, our results indicate that Asian koels produce individually distinct calls.

摘要

亚洲koel ( Eudynamys scolopacea) 是一种著名的育雏寄生鸟，每年夏天都会从印度来到巴基斯坦。该物种至少会发出五种响亮的叫声，据推测用于领地和交配行为。我们注意到野外个体之间的声音差异，并假设亚洲koels会产生个体不同的声音。为了测试这一点，我们记录了来自野外 46 只成年鸟类的 1 型 cooee 呼叫、coe 呼叫、1 型 coegh 呼叫、2 型 coegh 呼叫和 wurroo 呼叫，并测量了每种发声类型的 15 种不同的声学参数，包括频谱和时间. 我们还测量了个人编码 (PIC) 的潜力。通过逐步交叉验证的判别函数分析 (DFA) 进一步分析 PIC 值≥1.1 的参数。DFA 准确分类了 86.5% 的类型 1 cooee 调用、95.7% 的 coe 调用、91.5% 的 1 型 coegh 呼叫、82.2% 的 2 型 coegh 呼叫和 83.3% 的 wurroo 呼叫，这些呼叫是从这些呼叫被记录下来的个人发出的。因此，与我们的假设一致，我们的结果表明亚洲 koels 会产生单独不同的叫声。