Friday, August 26, 2011

Where do the Woodpeckers go?

While birding my lunch-hour patch, I saw a Northern Flicker and it struck me that I hadn't seen one in awhile.  My trusty eBird records confirmed that I hadn't reported one from my patch since the first week of May.  Where have they been these last couple months?

Even in my yard, our Downy Woodpecker (that was such regular visitor that my 4-year-old named her "Elizabeth") has been missing for a few weeks until just a couple days ago.  Where had she been?

My theory - before looking at any eBird information - is that the woodpeckers escape the heat of the valley floor and head for the coolness of the wooded hills and mountains.

eBird abundance charts indicate lower observations in the month of July.  But, is that just because birders are birding less?  Looking at eBird sightings maps on a month-by-month for the Boise and Salt Lake areas also shows fewer sightings of woodpeckers in the summer months.

I would be interested in seeing eBird data that could be sorted by elevation above sea level.  That might yield more clues about where birds are going during the changing seasons.  eBird used to have the option to enter elevation, but I don't see it any more.  I know mapping software is now so good that elevations for pretty much any point on a map can be obtained, so maybe it is no longer necessary to ask birders to enter their best guesses as to their altitude when observing birds.

What has been your experience with woodpecker seasonal disappearance where you live?  Do you have any thoughts or theories? ...or absolute scientific knowledge?

4 comments:

  1. I noticed the lack of woodpecker observations too, in the summer months in Idaho, when I made my woodpecker posts in July (http://annafasoli.blogspot.com/2011/07/woodpeckers-of-idaho-part-2.html). I attributed it to less people birding in these months, but that may be incorrect. Maybe they are seeking better natural food sources for their young, so we don't see them as often in easy-to-see places like bird feeders?

    ReplyDelete
  2. I have a hairy woodpecker, like your downy woodpecker, that has visited our place. That's what my bird book calls him. He loves our suet feeder, when I put it out. Don't do it much any more since the European starlings decide to come in and eat all of it in one day. I hate that! We also have flickers and they are around. I'm visiting from Steve Creek's blog!

    ReplyDelete
  3. I think we see fewer woodpeckers in the middle of the summer because they are nesting. Since woodpeckers are cavity nesters and nest mainly May through July, I hypothesize that they spend more time near their nest sites gathering insects to feed their young and don't frequent backyard feeders for that reason. There is typically at least a month of laying, incubating and then feeding young in the nest.

    Northern Flickers incubate for almost two weeks, then it's nearly another four weeks before the chicks fledge. During most of this time at least one parent is in the nest incubating the eggs or brooding the young for at least the first week after hatching. That would mean that we would only see half the Flicker population during those two to three weeks.

    According to Birds of North America Online, "In California, numbers increase in fall and winter as migrants arrive from the north; California breeders also move from higher to lower elevations during the winter." I think this is the main reason I see far more Northern Flickers in the spring, fall and winter than I do in summer.

    Here is a summer distribution map of the Red-shafted Flicker we have in the west and one for the Yellow-shafted eastern variety. You can see that they seem to be most dense in areas of open woodlands.

    ReplyDelete
  4. Robert, I agree with Larry's theory. I was going to suggest the same ting. I saw NOFL in the spring when they first came throuh, then didn't see them again for awhile, then suddenly they showed up with young and I am seeing them on a regular basis now. As for the downies and hairys it has been pretty much the same. I never have as many hairys as downies and was but the downies have been regular all summer. I have noticed the increase in population of downies over the past month as they have brought their young to the feeders. I have seen up to 5 birds at one time on the suet! Parents were feeding the young but now the young are coming by themselves so I see them in scattered groups of 2 or 3 or singles. Good Question though. Interesting to ponder.

    ReplyDelete