As regular CFZ-watchers will know, for some time Corinna has been doing a column for Animals & Men and a regular segment on On The Track... particularly about out-of-place birds and rare vagrants. There seem to be more and more bird stories from all over the world hitting the news these days so, to make room for them all - and to give them all equal and worthy coverage - she has set up this new blog to cover all things feathery and Fortean.

Saturday 27 October 2012

Brainy birds stash stores


We know that squirrels make the most of fall's plenty by hoarding nuts for the winter, but the fact that birds also store, or cache, food goes largely unappreciated. Through clever observation and experiments, biologists have found that food caching (from the French cacher, "to hide") has developed to a high art in some birds.

Take the chickadee, for instance. Chickadees put tens of thousands of food items a year into short-term storage. They usually retrieve and eat the food in the space of several days. Each food item is cached in a different place to make it difficult for thieves to steal all the food at once. When hiding a new item, they remember their previous storage sites and avoid placing caches too close together. Chickadees remember each hiding place for around a month, even though they may be scattered widely across a bird's territory. Research shows they use visual cues to navigate back to each of their cache sites by a combination of larger landscape features, particularly verticals, and use of the sun as compass. Smaller local details are not as critical, probably because these often change in a forest. When retrieving food, they remember which sites have been emptied, either by them or by robbers, to avoid fruitless searching.

How does a tiny bird have such brain power?

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