The long-range echo scene of the sperm whale biosonar

Sperm whales use their gigantic nose to produce the most powerful sounds in the animal kingdom, presumably to echolocate deep-sea prey at long ranges and possibly to debilitate prey. To test these hypotheses, we deployed sound recording tags (DTAG-4) on the tip of the nose of three sperm whales. One of these recordings yielded over 6000 echo streams from organisms detected up to 144 m ahead of the whale, supporting a long-range prey detection function of the sperm whale biosonar. The whale navigated this complex acoustic scene by maintaining a stable, long-range acoustic gaze suggesting continual resource evaluation. Less than 10% of the echoic organisms recorded by the tag were targeted for capture and only 18% of the buzzes were emitted within the 50 m depth interval of maximum organism encounter rate, demonstrating echo guided prey selection. Buzzes were initiated >20 m from the prey, showing that sperm whales do not debilitate their prey with sound, but trade echo levels for redu...抹香鲸凭借其巨大的鼻结构发出动物界最强劲的声响，推测其用途包括远距离回声定位深海猎物，或可能通过声响使猎物丧失行动能力。为验证上述假说，我们在三头抹香鲸的鼻尖处部署了声音记录标签（DTAG-4）。其中一次录音采集到了该鲸前方144米范围内探测到的生物所产生的超过6000条回声流，这一结果支持了抹香鲸生物声呐具备远距离猎物探测功能的推论。该抹香鲸通过维持稳定的远距离声学凝视来导航这一复杂声学场景，表明其在持续评估潜在猎物资源。标签记录到的回声目标生物中，仅有不足10%被选为捕获目标；且仅有18%的捕猎咔嗒声（buzzes）在生物遭遇率最高的50米深度区间内发出，这证明抹香鲸是通过回声引导来选择猎物的。捕猎咔嗒声均在距离猎物20米以上时启动，这表明抹香鲸并非通过声响使猎物丧失行动能力，而是以回声强度换取缩减……