ommon practice of the spider is to first immobilise and then encase captured prey in a silky shroud for later consumption. Certainly, there's enough evidence in the biological world that shows that survival is predicated on a number of factors, one being the availability of food supply. But is there also evidence to prove that organisms are both discriminate in what they devour, possess instinct and recall that drives them to engage in certain behaviours that can ensure survival, when food supplies become scarce? The answer would be yes on both counts.Many species anticipate potential scarcity of food supply and store away food for this period. We've all witnessed squirrels almost giddy in the fall storing nuts for the winter. Likewise, we've seen and heard the hum of bees busy manufacturing honey. I recall one case of discovering a little cache of peanuts, sesame seeds and M&M's inside a cardboard box on the top shelf of the workbench in my garage one winter that had been tidily stashed away for the coldest season by a resident family of field mice. Goodness knows where they found the ingredients to make this trail mix blend, but it certainly struck me that they are crafty little critters.
Some species use their own bodies as a storehouse for later nutrition and retire to winter quarters when the habitat may be difficult in which to forage. Hibernation and aestivation are both quiescent or dormant states of reduced metabolic activity, where the organism draws upon reserves until the habitat is more welcoming and food resources more abundant.
Remember the image on this post that showed the food stowing activity of the Acorn Woodpecker, Melanerpes formicivorus? Residents of environments that experience seasonal pulses of food items, followed by periods of scarcity, they undertake to stow away supplies to compensate for varying availability. Years ago in the 1920's William E. Ritter performed a study of the California Woodpecker, paying close attention to their food-storing activities. His interest was to attempt to determine what was their primary desired food source; when was it consumed and was there any particular rhyme or reason for the manner in which they built the caches, also known as "granaries". Theory suggested that despite many thousands of acorns that had been placed in the bark of trees in the woodland, the nut meats were not the primary food source of the woodpecker at all, but rather the worms or grubs that were often inside the nut.
Great care is given to the manner in which the cavities are fashioned in which to place the acorns. It seems that the species knows the desirability of acorns by other residents of the habitat, and therefore each hole was drilled to make sure that the acorn would fit snuggly, while being sufficiently recessed so that rodents and other competing individuals could not pry them loose and pillage the food supply. Ritter concluded that drilling or drumming away at the bark of trees was not always a function to create neat little receptacles for acorns, but incident to the woodpecker's pursuit of insects residing in the bark itself.
Woodpeckers have generalised foraging repertoires, and as a group undertaking they stow away for a "rainy day" and assist in guarding stored items. Observation conducted over a period of several seasons by Ritter also showed that the woodpeckers raided the granaries to retrieve, first, acorns that were grub-riddled and left behind those acorns without grubs that offered simply the acorn nutmeat. Presumably, these grub-free acorns were considered a secondary food choice. Ritter also noted that, in seasons of substantial acorn availability, granaries were stocked to the hilt, to the degree that the population could not consume all of the acorns. When the acorns began to rot they were abandoned.
More recently, another discovery in Mexico has determined that the woodpecker is a remarkable "structural engineer", as well. Yucca plants have a relatively hollow stalk, that is divided internally into several chambers. The woodpecker, resident to Mexico, learned that by drilling a hole at the uppermost region of each chamber and another hole at the lowest level of each chamber, it could drop acorns through the top hole and the yucca would serve as a safe storage container, and work much like PEZ dispenser. This plant made such an ideal storehouse for the woodpecker's harvest that observation proves that some granaries are located more than 30 miles away from the nearest oak tree. Yes, it appears from this empirical research that woodpeckers are decidedly industrious engineers. They recognise the true value of the work invested in harvesting and safe conservation of their harvesting efforts that they'd even entertain flying up to 60 miles to transport one acorn to their coveted storage place.
The question then remains, is it instinct alone, or is it a combination of instinct and experience that promotes these birds to lay by stores of provisions for the winter, even when it involves travelling over significant distances and a sizable investment in energies to do so?
Doug's rather curt response to me by email in April 2005 caused me to wonder all the more what the real reason was that he'd approached me in the ILW chat room the first week of January 2004, and to continue to prolong the myth through communication for a year and a half. He had no shortage of nourishment and attention, being married. So why masquerade as he had with me and why invest so much time and energy in something he would later deny or abandon? And if indeed his interest was to develop a friendship with me, with no other interest, why pretend, in the end, as if we had never met?
Was it that I was symbolic of a grub that he'd unearthed, perhaps by accident or as a result of instinct or some biological imprinting, while drilling at the bark of a tree and doing what a normal woodpecker does? Since there was a ready-cache of food supply at the time, was I simply stored away and left for possible later consumption? Worse yet, had it been instinct or experience that had caused him to shove me firmly into the vice-like cavity to remain there until rotted and of no nutritious value to anyone?
These questions would plague me until fall of 2005, when I would be able to ask him directly....
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