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By HERB WILSON September 9, 2007

Today we will begin with some wisdom of the ages as given in one of Aesop's fables, "The Ant and the Grasshopper." This lesson is particularly relevant as summer wanes and cool fall weather will soon enough lead to the cold of winter.

"In a field one summer's day a grasshopper was hopping about, chirping and singing to its heart's content. An ant passed by, bearing along with great toil an ear of corn he was taking to the nest. "Why not come and chat with me," said the grasshopper, "instead of toiling and moiling in that way?"

"I am helping to lay up food for the winter," said the ant, "and recommend you to do the same."

"Why bother about winter?" said the grasshopper; we have got plenty of food at present." But the ant went on its way and continued its toil. When the winter came, the grasshopper had no food and found itself dying of hunger, while it saw the ants distributing every day corn and grain from the stores they had collected in the summer. Then the grasshopper knew: It is best to prepare for the days of necessity."

STORING FOOD FOR WINTER

Quite a number of birds follow the ant's advice and put food away for seasons of scarcity. Winter poses a particular challenge for Maine birds. Insects are virtually absent, snow covers lots of potential food and the days are so short that birds have little time to find enough food to last them through the night.

Black-capped Chickadees provide an excellent example of food- hoarding behavior. Usually seeds are hoarded, although insects and spiders may be stored as well. Insects and spiders are prepared before storage by removing the head. Chickadees readily cache sunflower seeds and pieces of suet from bird feeders. You have probably seen this behavior at your own feeders. A chickadee will remove the husk of a seed before caching it.

Chickadees do most of their hoarding in the fall. The number of seeds stored is staggering. Over a thousand items may be stored in a single day and, over the course of autumn, 50,000 to 80,000 spruce seeds were stored at one study site.

Sites for food storage are varied. Typical hiding places are cracks or crevices in woody vegetation, under bits of bark (particularly birch bark), in clusters of conifer needles, in the ground and even in the snow.

An interesting pattern emerges when one compares the frequency of hoarding in different parts of the range of black- capped chickadees. Hoarding is frequently noted in northern populations, as reported in studies done in upstate New York and Ontario. In milder climates such as southern Illinois, food caching is rarely seen. Chickadees there seem to be able to get away with the grasshopper strategy!

STORAGE LOCATION VARIED

Unlike some birds that hoard food at a single location, chickadees store their food in widely scattered locations. The advantage of scattering hiding sites is that other chickadees will not be able to steal all of their stored food if a thief encounters a stored seed. The disadvantage, of course, is the need to remember where all the seeds are stored.

The spatial memory of chickadees has been a productive and exciting area of ornithological research. Research done at the University of Toronto clearly showed that chickadees can remember their hoarding sites 24 hours after storage. Chickadees also spent little time at sites where food had been removed, either by the chickadee that stored the food or by a thieving chickadee that stole the cache.

Remembering where food is stored for a day is impressive, but what benefits does such short-term memory give for a chickadee on a cold February day. Recent research indicates that chickadees have a longer-term memory for food. Chickadees were able to find food 28 days after caching it. To make matters difficult for researchers, chickadees are also known to take a hoarded seed and then store it somewhere else.

Neurobiologists have shown that a particular...