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The term “birdbrain” is typically used to describe a person who has a limited attention span or lacks intelligence. However, recent studies in the animal world have shown that some birds are actually quite intelligent. In particular, birds of the Corvidae family (which includes crows, ravens, jays, magpies, and nutcrackers) have demonstrated remarkable cognitive abilities. Corvids have shown the ability to make and use tools, plan ahead, and solve multistep problems. In addition, they have remarkable memories. Corvids are able to recall the locations of thousands of hidden food caches, and their complex social structures require them to recognize and keep track of individuals and the social positions of members over time. 

For example, wild New Caledonian crows are known to fashion twigs into hooked tools to pull insects from tree holes. They have also demonstrated the ability to learn how to use different objects, such as rocks, as tools to solve complex problems. In one scientific experiment, a crow was presented with a puzzle: in order to reach an inaccessible piece of meat, the crow needed to use one tool to acquire other tools, which could then be used to get to the meat. The crow managed to successfully carry out a series of eight different steps in the correct sequence to eventually reach the trapped meat. In another recent study, researchers presented crows with various experiments involving tubes of water and a floating piece of meat. The meat was out of reach until the birds dropped objects into the proper tube to displace the water and bring the meat closer to the top. The researchers found that the crows seemed to understand the causal relationship between the properties of an object and its effectiveness for the task; in other words, the birds tended to choose solid sinking objects that displace water better than hollow or floating objects. The scientists concluded that the reasoning ability of the crows is comparable to a five-to-seven-year-old human child.

Some corvids also display long-term spatial memory. For example, before winter, Clark's nutcrackers hide food (such as seeds, nuts, and worms) in approximately 10,000 different locations spread over a wide area. Amazingly, the birds can recall the locations of the caches up to nine months later. Some corvids, such as western scrub jays, also appear to use counterstrategies to protect their food from being stolen, which may indicate complex social intelligence. Scrub jays continually re-cache—or re-hide—their food if they know they are being watched. When they are finally alone, they will relocate the food one last time. Interestingly, scrub jays are much more likely to demonstrate re-caching behavior if they themselves have stolen food from another bird's cache in the past. 

• Why do the birds scatter their caches, rather than hiding everything close together?
• How might caching change the environment?
• Why do corvids bury significantly more food than they recover?
• How do corvids decide which food to recover first?

• Use the following suggestions to guide students' viewing of the video:

• Before: Ask students: Have you ever put something aside to be used later? Describe some examples of when you have stored something for future use.

• During: Have students take notes about why the birds hide food and the number of locations that they use.

• After: Have a class discussion about planning ahead and storing food. What is the purpose of caching? Why do animals do it? Why do you think the birds in the video use so many hiding places? What are some of the potential hazards of hiding something for later use?

• Ask students to imagine that they will not have access to fresh food for many months during winter and they will need to prepare by storing food. Have them work in small groups to discuss what kind of foods they would store and how they would store it. Remind them to consider how long the food needs to be stored when deciding where to keep it. Have them create a poster detailing why they chose those particular foods and storage methods.