Japan Crows Use Car Tires to Crack Nuts, Crosswalk Lights to Feed

BBC Studios

Urban crows overcome tough shells and traffic hazards by placing nuts under vehicle tires and timing food retrieval with pedestrian walk signals.

AI-assisted summary of Wild crows inhabiting the city use it to their advantage - David Attenborough - BBC wildlife — original source. Check the original for full context.

Source published: 2007-02-12

Key ideas

Wild crows in Japan have adapted to urban environments by utilizing human infrastructure to access hard-to-crack food sources. (0:02)
When dropping nuts from great heights onto roads fails to crack tough shells, crows intentionally place nuts in traffic lanes for car tires to crush. (0:02)
To solve the hazard of moving traffic during food retrieval, crows position themselves at pedestrian crosswalks and monitor traffic light cycles. (1:09)
The birds safely harvest crushed nut pieces alongside pedestrians during red lights before vehicle traffic resumes. (1:09)

Detailed notes

## Background Published on YouTube by BBC Studios on February 12, 2007, this BBC wildlife clip features footage from the BBC Earth archive. The page description highlights how birds adapt to metropolitan life, focusing specifically on crows in Japan that have integrated city infrastructure directly into their foraging behavior.

## TL;DR Narrated by David Attenborough, the clip documents the ingenious foraging adaptations of wild crows living in urban Japan. When dropping hard-shelled nuts from high perches onto asphalt fails to break them, the crows place the nuts directly into roadway traffic to let passing car tires crush the shells. To solve the dangerous problem of collecting the food without being run over, the birds station themselves beside pedestrian crosswalks. They patiently wait for traffic lights to halt vehicles, stepping into the street alongside human walkers to safely retrieve their meal.

## Atmosphere & style The clip carries David Attenborough’s signature tone of gentle awe, measured curiosity, and calm observational humor. Watching mundane city infrastructure—traffic lights and pedestrian crossings—reimagined through an animal's sharp problem-solving creates a delightfully suspenseful and charming experience. It feels like an eye-opening glimpse into animal intelligence, blending classic natural history storytelling with the everyday bustle of urban street life.

## Bulletin - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Wild crows in Japan have adapted to urban environments by utilizing human infrastructure to access hard-to-crack food sources. - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) When dropping nuts from great heights onto roads fails to crack tough shells, crows intentionally place nuts in traffic lanes for car tires to crush. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) To solve the hazard of moving traffic during food retrieval, crows position themselves at pedestrian crosswalks and monitor traffic light cycles. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) The birds safely harvest crushed nut pieces alongside pedestrians during red lights before vehicle traffic resumes.

## Key takeaways - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Urban crows in Japan demonstrate high adaptability and foraging skill within metropolitan landscapes. - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Tough-shelled nuts pose a physical barrier that crow beaks cannot penetrate on their own. - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Crows initially attempt to break nuts open by dropping them from heights onto hard road surfaces. - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Aerial impact alone is often insufficient to crack particularly durable shells. - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Crows innovate by letting passing automotive traffic act as a heavy crushing mechanism. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) Using moving vehicles to crush nuts creates the secondary danger of birds getting run over while retrieving the food. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) Certain crows overcome this hazard by stationing themselves adjacent to designated pedestrian crossings. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) The crows exhibit an understanding of traffic signals by waiting patiently for traffic lights to stop vehicles. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) When pedestrian signals activate, crows walk into the crosswalk alongside humans to collect crushed nut fragments in complete safety. - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) This multi-step foraging strategy highlights the sophisticated integration of human urban patterns into wild animal behavior.

## Detailed walkthrough ### [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Urban Crows and the Challenge of Cracking Tough Nuts

In modern urban environments, crows have proven to be exceptionally resourceful, adapting their natural foraging behaviors to metropolitan human landscapes. Narrator David Attenborough observes this remarkable adaptability in action on the streets of Japan, pointing out: “Crows have become highly skilled at making a living in these new urban environments.” Faced with food sources that their beaks alone cannot easily breach, these Japanese city crows have engineered a clever solution to access a meal that would otherwise remain out of reach.

The birds naturally try to break open hard-shelled nuts by carrying them aloft and dropping them onto hard asphalt roadways from high above. While this aerial bombardment works on occasion, many nuts possess shells far too sturdy to crack upon impact alone. Recognizing the limitations of brute height, the crows turn the city itself into an anvil, altering their strategy to let passing automotive traffic do the heavy crushing for them.

```mermaid flowchart TD accTitle: Crow Nut-Cracking Strategy Evolution accDescr: Flowchart showing how crows adapted their method from aerial drops to utilizing traffic and pedestrian lights.

subgraph InitialMethods["Initial Attempts"] A["Drop nut from height onto hard road"] --> B{"Is shell too tough?"} B -->|"Yes"| C["Drop nut directly into roadway traffic"] end

subgraph RefinedStrategy["Traffic Safety Refinement"] C --> D{"Problem: Risk of getting run over"} D --> E["Station near pedestrian crossing"] E --> F["Wait for traffic light to turn red"] F --> G["Retrieve cracked nut in safety"] end ```

[01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) Mastering the Pedestrian Crossing

Dropping nuts directly in front of oncoming vehicles solves the cracking problem, but it immediately introduces a deadly hazard: retrieving the crushed fragments without being struck by cars. As David Attenborough explains, “The problem now is collecting the bits without getting run over.” To circumvent the dangerous moving traffic, several birds have developed an extraordinarily refined and calculated technique centered on human infrastructure.

Rather than darting recklessly among speeding tires, the crows position themselves right beside designated pedestrian crossings. They carefully monitor the flow of the intersection, waiting patiently for the traffic lights to change and bring vehicles to a complete halt. Once the pedestrian signal permits safe passage, the crows hop calmly into the crosswalk alongside walking humans, collecting their freshly cracked nut meat in total safety before the lights turn green again.

- **Initial foraging tactic**: Dropping hard nuts onto paved roads from a great height to crack them open. - **The mechanical upgrade**: Placing tough nuts directly into the roadway so vehicle tires crush the shells. - **The safety adaptation**: Utilizing pedestrian crosswalks and traffic light cycles to collect cracked nut fragments without risking injury from moving cars.

## Notable quotes > [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) Crows have become highly skilled at making a living in these new urban environments. — David Attenborough

## Mentioned David Attenborough, BBC, BBC Earth, BBC Studios, Japan

## Video description Want more natural history and wildlife videos? Visit the official BBC Earth channel: http://bit.ly/BBCEarthWW

BBC Earth The BBC Earth YouTube channel is home to over 50 years-worth of the best animal videos from the BBC archive. With three new videos released every week there’s something for all nature loves from astounding animal behaviour to beautiful imagery. Click here to find our more: http://bit.ly/BBCEarthWW

Many birds adapt to metropolitan life, in this clip you can see how crows in Japan have integrated city life into their behaviour. From the BBC.

This is a channel from BBC Studios who help fund new BBC programmes. Service information and feedback: https://www.bbcstudios.com/contact/contact-us/

[Source](https://www.youtube.com/watch?v=BGPGknpq3e0)

中文简报

日本乌鸦用车轮碾碎坚果，看红绿灯过斑马线觅食城市乌鸦将坚果放在车轮下压碎，并配合行人通行信号去取食，以此克服坚硬外壳并规避交通危险。该片段由戴维·爱登堡（David Attenborough）解说，记录了生活在日本城市的野生乌鸦巧妙的觅食适应行为。当从高处向沥青路面投掷硬壳坚果无法摔碎时，乌鸦会将坚果直接放在车道上，让过往车辆的轮胎压碎外壳。为了解决捡食时避免被撞的危险难题，这些鸟类会停留在人行横道旁耐心等待红绿灯阻断车流，然后跟随过马路的行人一同走上街道，安全地取回食物。日本的野生乌鸦已适应城市环境，利用人类基础设施来获取难以敲开的食物来源。 (0:02) 当从高处将坚果摔向路面无法砸开坚硬的外壳时，乌鸦会特意把坚果放在车道上让汽车轮胎碾压。 (0:02) 为了化解在取食过程中遭遇行车带来的危险，乌鸦会停留在人行横道旁并观察红绿灯的变化周期。 (1:09) 在车辆交通恢复前，这些鸟类会在红灯期间与行人一同安全地捡拾压碎的坚果碎块。 (1:09)

Detailed notes — zh

## Background 该视频由 BBC Studios 于 2007 年 2 月 12 日发布在 YouTube 旗下的 BBC Earth 频道。视频简介指出，许多鸟类已经适应了都市生活，该片段记录了日本城市的乌鸦如何将现代都市环境巧妙融入自身的生存行为中。 ## TL;DR 在日本的一座现代城市中，野生乌鸦面对单纯靠高空抛摔无法砸碎的坚硬坚果，展现出了惊人的环境适应与创新解决能力。它们主动调整策略，将硬壳坚果精准投放在繁忙车道上，借助疾驰车辆的车轮将其彻底碾碎。为了避免在川流不息的车流中捡食时被撞击碾压，乌鸦进一步摸清了人类交通信号灯的规律，选择在人行横道旁静候红灯亮起、车流停滞。趁着行人通行的时间差，它们与过街行人并肩步入斑马线从容回收果仁，完成了令人惊叹的认知升级与工具借力。 ## Atmosphere & style 全片伴随大卫·爱登堡（David Attenborough）标志性且沉稳温和的经典解说，营造出兼具科学严谨与趣味探索的观赏体验。叙事随着乌鸦破解一道道生存难题层层递进，从高空抛摔受挫到借力车流破壳、再到洞悉红绿灯信号，充满豁然开朗的戏剧感与惊叹感。观众在短短两分钟内能真切感受到野生动物令人拍案叫绝的狡黠智慧，以及生命在钢筋水泥森林中坚韧而从容的奇妙生态。 ## Bulletin - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) 日本城市中的乌鸦掌握了借助城市车流破壳的创新觅食策略，解决了高空抛投无法摔裂特硬坚果的难题。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 为了避免在川流不息的车流中被撞伤，乌鸦进一步理解并利用了人类的人行横道与交通红绿灯信号。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 乌鸦在红灯阻断机动车流、绿灯亮起行人过街时才步入斑马线捡拾果仁，展现了野生动物极高的认知进阶与都市适应能力。 ## Key takeaways - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) 大卫·爱登堡指出，乌鸦在现代新兴的都市环境中已变得极其擅长谋生与适应。 - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) 乌鸦原有的传统取食方式是从高空将坚果掷向硬化路面，但面对外壳格外坚硬的坚果时常常无效。 - [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) 为了破开坚硬外壳，乌鸦主动借力城市车流，将坚果精确投放于车道中央供疾驰的汽车碾碎。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 利用车辆碾压带来了致命的新风险：穿梭在高速行驶的车流中捡拾坚果碎片极易被汽车撞伤或碾死。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 部分乌鸦将观察点选在路口的人行横道旁，通过观察交通信号来规避车流危险。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 乌鸦学会了等待红灯让车流停下，趁机动车道静止的窗口期进入路面取食。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 当行人信号灯转绿时，乌鸦与过街行人并肩走上斑马线，从容安全地回收地面被碾裂的坚果果仁。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 这种进阶策略表明乌鸦不仅理解物理层面的因果关系（车轮可碾碎坚果），还理解了人类社会的规则信号（红绿灯代表车流停止）。 - [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 乌鸦将人工基础设施转化为生存工具的行为，生动展现了野生动物在钢筋水泥环境中的高度智力与生态适应机制。 ## Detailed walkthrough ### [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) 都市乌鸦的创新取食智慧与车流利用在现代都市的钢筋水泥丛林中，野生动物往往面临严峻的生存挑战，但也有物种展现出了惊人的适应能力与学习智慧。解说员大卫·爱登堡（David Attenborough）在片中指出：“crows have become highly skilled at making a living in these new urban environments”（乌鸦在这些新兴的城市环境中谋生变得极其熟练）。在日本的一座城市里，乌鸦面对外壳坚硬、常规方式无法开启的坚果，创造性地开发出了一种独特的进食策略。通常情况下，乌鸦会叼起坚果飞向高空，再将其掷向坚硬的公路路面，希望通过重力撞击将外壳砸碎。爱登堡描述道：“Dropping a nut from a great height onto a hard road does sometimes crack it, but some nuts are particularly tough”（从高处把坚果摔到坚硬的马路上有时确实能摔裂它，但有些坚果却格外坚硬）。面对这种单纯依靠自身力量无法解决的困境，乌鸦并没有放弃，而是将视线转向了城市中最密集、最具破坏性的力量——道路上的机动车流。它们主动调整策略，飞到道路上方将硬核坚果精确抛投在车道中央，借由疾驰而过的汽车车轮将坚果直接碾碎。 - **生存环境**：日本城市交通主干道及周边树木与电线。 - **原始取食方式**：高空抛投砸击硬化路面，对普通坚果有效，但遇到极坚硬外壳时往往失败。 - **环境借力行为**：识别并利用疾驰车辆的重量与下压力，将坚果置于行驶路线中借助车轮碾破外壳。 --- ### [01:09](https://www.youtube.com/watch?v=BGPGknpq3e0&t=69s) 红绿灯与斑马线：安全进食的策略进阶将坚果推入车道虽然顺利解决了破壳问题，但随之而来的是一个致命的新难题：在川流不息的车流中，如何安全地捡拾碾碎的果仁而不被车轮撞击或碾死。正如大卫·爱登堡所言：“The problem now is collecting the bits without getting run over”（现在的难题是如何在不被汽车压死的情况下捡回那些碎块）。为了克服这一生命危险，一部分乌鸦进一步改进并完善了自己的技术，将城市的人类交通规则融入了自身的行为本能中。这些聪明的小鸟选择在路口的人行横道（斑马线）旁安营扎寨，耐心观察交通状况。爱登堡总结道：“Wait for the lights to stop the traffic, then collect your cracked nut in safety”（等待红灯让车流停下，然后安全地捡拾被压碎的坚果）。它们静静守候在路旁，直到行人信号灯转绿、机动车道红灯亮起，所有机动车停下等待行人过街时，乌鸦才大摇大摆地走入斑马线，与过街行人并肩同行，从容不迫地在绝对安全的环境下回收地面上已被碾裂的美味果仁。 ```mermaid flowchart TD accTitle: 乌鸦利用城市交通破壳取食的行为演进 accDescr: 展示乌鸦从最初高空摔坚果到利用汽车碾压，再到依靠红绿灯在人行横道安全取食的策略进阶过程。 subgraph Phase1["传统取食方式与局限"] A["高空抛投坚果至硬地"] --> B{"坚果是否破碎？"} B -->|"普通坚果"| C["直接食用"] B -->|"特硬坚果"| D["外壳完好，无法破壳"] end subgraph Phase2["引入城市工具：汽车碾压"] D --> E["将坚果投放至行车道"] E --> F["机动车车轮碾碎坚果"] F --> G{"面临新困境：穿梭车流极度危险"} end subgraph Phase3["行为认知升级：利用红绿灯与人行横道"] G --> H["选择人行横道旁驻足守候"] H --> I["等待红灯亮起阻断车流"] I --> J["趁车辆停止随行人步入斑马线"] J --> K["安全捡拾已碾碎的果仁"] end ``` - **行为认知升级**：乌鸦不仅理解因果关系（汽车车轮 = 开壳工具），更理解了人类社会的规则信号（红绿灯 = 车辆静止信号）。 - **行动窗口期**：利用行人和机动车的通行交替时间差，在信号灯转换的车流静止期内快速取食。 - **生态适应意义**：生动展示了野生动物将都市人工基础设施转化为自身觅食工具的高度智商与适应机制。 ## Notable quotes > [00:02](https://www.youtube.com/watch?v=BGPGknpq3e0&t=2s) crows have become highly skilled at making a living in these new urban environments — David Attenborough ## Mentioned David Attenborough, BBC Studios, BBC Earth, 日本 ## Video description Want more natural history and wildlife videos? Visit the official BBC Earth channel: http://bit.ly/BBCEarthWW BBC Earth The BBC Earth YouTube channel is home to over 50 years-worth of the best animal videos from the BBC archive. With three new videos released every week there’s something for all nature loves from astounding animal behaviour to beautiful imagery. Click here to find our more: http://bit.ly/BBCEarthWW Many birds adapt to metropolitan life, in this clip you can see how crows in Japan have integrated city life into their behaviour. From the BBC. This is a channel from BBC Studios who help fund new BBC programmes. Service information and feedback: https://www.bbcstudios.com/contact/contact-us/ [Source](https://www.youtube.com/watch?v=BGPGknpq3e0)

Source quotes

[0:02] David Attenborough: crows have become highly skilled at making a living in these new urban environments

Source quotes

[0:02] David Attenborough: Crows have become highly skilled at making a living in these new urban environments.

Original transcript

[0:02] crows have become highly skilled at [0:04] making a living in these new Urban [0:06] environments in this Japanese City they [0:09] have devised a way of eating a food that [0:11] normally they can't manage [0:33] dropping a nut from a great height onto [0:35] a hard Road does sometimes crack it but [0:38] some nuts are particularly [0:41] tough so the crows have devised A Better [0:50] Way drop it among the traffic [1:09] the problem now is collecting the bits [1:12] without getting run [1:14] [Applause] [1:19] over so some birds have refined their [1:23] technique they station themselves beside [1:26] pedestrian Crossings [1:43] wait for the lights to stop the [1:56] traffic then collect your cracked nut in [2:00] safety