In order to prevent other birds from stealing the food they are storing for later, Eurasian jays, a type of corvid, minimizes any auditory hints a potential pilferer may use to steal their cache (food that is buried for later use). The new research was published today, 05 December, in the journal Proceedings of the Royal Society B.
Corvids are prolific cachers (or hoarders), burying food such as acorns in several thousand locations over the course of a year. When food becomes scarce during winter and spring, they remember where they buried their caches and retrieve the food items. However, pilfering of caches is commonplace. As a result, they are often trying to minimize other birds stealing their food and maximize the food that they steal.
In the first experiment, the researchers gave the jays options to hide food in substrates which varied in the amount of noise they made (a tray containing noisy gravel and a tray containing quiet sand). The birds' preferences for using these different substrates were tested when they were alone, when they had another bird that could see and hear them and when there was another bird that could hear but could not see them.
The researchers found that if a Eurasian jay is caching and hears but does not see another bird nearby it will hide its cache in the less noisy substrate (for this study, sand rather than gravel). This is presumably done to avoid drawing unwanted attention from potential thieves that might then try to view the location of the cache.
In the second experiment, the scientists measured how many times the subjects vocalised depending on whether they were watching another jay caching, another jay stealing caches that the subject had made themselves, another jay that was not caching or stealing, or an empty compartment that contained no jay.
Rachael Shaw, a PhD student at the University of Cambridge and co-author of the paper, said: "As humans, we understand that other people can hear what we are doing, but there is only limited evidence for this ability in other animals. Our study of Eurasian jays is the first to report that a member of the crow family will suppress acoustic information by vocalising less when spying on another individual that is caching."
University of Cambridge: http://www.cam.ac.uk
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Fewer shark fins are being imported into Hong Kong, the epicenter of shark-fin soup, a culinary delicacy. But while the trade in shark fins may be down, the trade in shark meat is still going strong.
New study reveals participants unconsciously sniff their right hand after shaking it with others as part of process to pick up chemical signals about others
If you have ever struggled through a math class, you may not think of numbers as natural.
DNA analysis has revealed evidence for a massive migration into the heartland of Europe 4,500 years ago.
In the days before Amazon and TripAdvisor, how could you express your consumer outrage? For ancient Mesopotamians, it was seethe, stamp and bake
Alzheimer's researchers at Harvard for the first time are scanning the brains of healthy patients for the presence of a hallmark protein called tau, which forms toxic tangles of nerve fibers associated with the fatal disease.
Evidence of an ancient settlement was found in the most inaccessible forest in Central America
Strong drugs are rarely warranted to control the behavior of dementia patients, specialists say. But antipsychotic medicine is being overprescribed, and not just among residents of nursing homes.
Scientists are refining what constitutes "normal"