Summer World_ A Season of Bounty - Bernd Heinrich [29]
Fig. 13. Red-eyed vireo pair and their nest, which is typically decorated with several pieces of hornet paper.
When vireos build their nests in late June the hornets’ nests are still small—about the size of a baseball, the same as the vireos’ nests. From a distance, from underneath, both look like gray blobs hanging from a twig. Might a crow, blue jay, chipmunk, or squirrel initially confuse one with the other? If these predators have experienced a wasp’s nest defense before, then a mere glimpse of wasp paper on a shape that looks like a wasp nest may, as in some of us who have had an experience with these wasps, be sufficient to prevent them from coming nearer to make a close inspection.
Birds are quick learners. Like us, they stay clear of even a single wasp. And we know that this has been so for millions of years, because several different families of flies, as well as some moths and even some beetles, have members that mimic wasps so closely in shape, size, coloration, sound and flight and other behavior, that a non-entomologist is unlikely to detect the difference and would be easily fooled by them. All these totally different insects ended up looking, acting, and sometimes also sounding like wasps because birds have avoided eating them and whatever resembled them. Squirrels, chipmunks, and deer mice routinely raid many bird nests, as do other birds. For the mammals who rely less on sight than bird predators, a wad of paper could also be a repellent simply because of its smell. There was thus scope for experiments.
I wanted to observe the learning curve of wasp-evasion in my tame ravens, and to that end invested effort trying to procure a currently occupied bald-faced hornet nest. In the summer of 2006 I succeeded in finding only one (instead of its finding me). The nest was in raspberry bushes in a heavily overgrown field near my camp in Maine. I wanted to introduce this wasp nest with its occupants to my ravens in Vermont, and decided to “hive” the wasps with their nest into a big plastic bucket. After donning a bee veil and putting on heavy gloves, I approached the nest with bush cutters. The occupants shot out at me as soon as I wiggled the first raspberry twig. One immediately stung me on the wrist. I retreated to wait a bit for the pain to ease up, and after about five minutes I came back for another try. This time I had also brought my bee smoker, and I cranked it up until it was belching big gray puffs. Did the wasps retreat? Not in the least. I was surprised, since honeybees are almost instantly calmed by smoke. The wasps, in contrast, were not fazed. They came after me whenever I made even the slightest move. I retreated again, planning to come back at night.
This time I crept up slowly, lunged forward with a wad of toilet paper in my hand, and successfully plugged up their nest entrance hole before they had time to react. I then snipped the raspberry twigs holding the nest, dumped it into the plastic bucket, and sealed it, all in less than ten seconds. Within about that time the volume of the wasps’ buzzing increased. The wad fell or was pushed out, and the hornets were exiting from their nest and hitting the inside wall of the bucket. It sounded as if someone was peppering it with dried peas.
During the five-hour drive from my cabin in Maine back to Vermont that night the wasps were undoubtedly jostled and agitated. But by the next morning the bucket was silent. I brought it into the aviary and cautiously lifted the cover, and as I did so only one wasp burst out to attack me. The rest were on the bottom, either barely crawling or dead.
My