Ned Boyajian, one of the best birders on the coast, was a good friend of Judy's. He has fact-checked most of the "Year with Judy" articles published this year. We are so grateful for that, as information has obviously changed over the years. He is the current compiler of the Hancock County Christmas Bird Count. This year's Hancock count is next Tuesday, December 20th. The Jackson County count is on Monday, January 2nd, 2017.
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| House Finch - photo courtesy Sharon Milligan ...."Were purple finches really unrecognized House Finches"... |
To me, Christmas Counts have always been the most enjoyable events of the birding year, even outranking that epitome of goofiness, the big day. I’m not sure just how many I’ve been on since my first in 1947, certainly well over two hundred, in seven states and three countries.
So I think I have a pretty good feel for what they are really like from an “in the trenches” perspective and have always wondered a bit about whether they are as valid a source of data as we like to think.
I assume that there are statistical techniques that can deal with some of the inevitable variations in input, and allow for interpretation of data in ways that are both valid and meaningful. Certainly on a continental basis good information has been obtained on such things as major wintering areas, cyclical invasions and the more pronounced long range trends.
But I’m thinking more of the state and local levels, where, I suspect, “smoothing” or “averaging out” techniques might not work too well.
We need also to consider variations in quality of effort, both in terms of participant competence and commitment. My experience strongly indicates that these can vary considerably from count to count. I particularly remember participating in two sets of side-by-side counts (one set on the east coast the other on the west) in which year after year one of the sets was peopled by keen and dedicated enthusiasts while in the neighbor the majority of the participants were incompetent. The problem here is not about the reporting of improbable sightings, an albatross in the birdbath or whatever. Compilers and editors can easily handle that sort of thing. Rather it is all that went unrecorded because the observers simply didn’t know how to search for, detect, identify and count birds.
I’ve also been on counts on which none of the participants would dream of beginning until well after sunrise or of lingering after dark, and on others in which virtually all coverage was from the car with perhaps an occasional roadside stop.
So there is a downside to the otherwise commendable policy of inviting and encouraging one and all to participate
Then too there is the often stated convention that Christmas Counts are purely a cooperative venture in which competition should have no part. Foo. I haven’t been on a Count yet that wasn’t competitive. And why not? It’s a major motivating factor and a good part of the fun.
But let us assume that all this was back in the bad old days and henceforth all observers will function as though they were clones of ole’ Roger P. himself and be as dedicated to lofty ideals as is a congressman. Just how accurate will be the state or local information garnered?
Coverage?
Personally, I have never been on a count that had adequate resources to cover all the worthwhile territory within its circle. Further, access can vary significantly from count to count. Some coastal counts may have the resources to cover open water within their circles, others may not. Some counts may be able to at least make a pass at most of their area, on others large tracts of prime habitat may be inaccessible.
Distribution?
Yes we can determine that there are a lot of Carolina Chickadees in Mississippi. But can we really determine where in the state they are most abundant by comparing counts with twenty-five participants to those with only twelve or with even as few as two participants?
Trends?
I recently had the opportunity to browse through the entire history of one of our local counts. In doing so some trends were clearly noticeable; the recovery of the Brown Pelican, the decline of the Loggerhead Shrike.
But in other cases I wondered whether what I was seeing may not have been participant-driven. The Purple Finch was recorded in fair numbers on the earliest counts but crashed just about the same time the House Finch first began to be recorded. Was this real or were many of those Purples really unrecognized House Finches?
In another case a certain water bird, which should not be here in winter, was seen in relatively good numbers for a period of several years with virtually no records before or after. Was this real or was there a participant active during that span of years who was particularly adept at detecting this species (or conversely, had a penchant for misidentifying it)?
Well then just what can a Christmas Count do?
For one, it can tell us with a fair degree of accuracy the number of species that x number of observers are likely to find in a day under a given set of circumstances. (How this number relates to the number of species actually present at the time is something else again.)
It can highlight major fluctuations in relative abundance from year to year and trends over a period of years at least on scale of “a whole bunch” to “hardly any”.
But most importantly, it can provide us, at a season filled with a host of festive occasions, one that is uniquely our own. Enjoy it.
This article was written around 2007
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