Whether or not the commonly used bird watching term “giss” actually has its origins in an old British military acronym for General Impression Size and Shape (GISS) is a question perhaps best left to the etymologists. However regardless of from whence it originated, it is a most handy tool to have in one’s field craft kit.
The basic concept of giss is really quite simple. With only a relatively quick look at something or someone, one can have at least a half-reasonable idea of what or who it is from the overall size, shape, and other basic significant characteristics. You might not be able to describe all the “field marks” of, say, your uncle Fred, but you can pick him out of a crowd instantly by knowing him to be a portly, middle-aged man of medium height who sports a long red beard and walks with a limp. The principle is the same with birds – in fact, most of us do it unconsciously when first sighting any bird, right down to the most basic level of determining that a creature seen is in fact a bird rather than a squirrel, a garden gnome, or your uncle Fred.
Yet while giss is often discussed in essays about bird watching field craft, I have recently been wondering if there might be such a thing as reverse giss. This would be applicable to all those situations when you see something or someone you know perfectly well but fail to be able to identify correctly as it, he, or she is observed in an unfamiliar location. This has happened to me many times with the most familiar of birds; I have not been able to immediately identify them simply because I saw them outside of the areas in which I most commonly see them.
The floor is now open for comment or rebuttal.
December 4, 2009 @ 22:12
I’ve noticed this with people moreso than with birds. If I see someone out of context from how I usually see them, I sometimes don’t recognize them.
This isn’t quite the same, but a few years ago I was helping out on a research project by monitoring the buildings I work in for window-killed birds during migration. One day, I found and collected a small bird for the researcher (under permit). It was obviously a warbler, but I didn’t recognize it immediately. I consider myself pretty familiar with the warblers here, but I actually had to crack open a book to confirm its identity. It was a Palm Warbler. I’ve seen many, many Palms, but I didn’t recognize one that I could examine close-up and at leisure.
The only thing I can figure is that my ID criteria for Palms is based mostly on context and behavior. I expect to see them close to the ground and, more than anything, pumping their tails. So I can easily see how seeing a familiar bird in an unfamiliar context, or behaving atypically, can cause confusion.