Fascinating account! Thanks Tom! Mike Koutnik
Sent from my iPhone > On Jan 10, 2017, at 2:09 PM, Tom Bell <bell.to...@gmail.com> wrote: > > Reading Bruch Falls robin roost account I looked up mine. It is a bit long. > That roost site has not been used since with any high numbers. > Winter Roost Site for American Robins > > > > I live on Grey Cloud Island, the very southwest corner of > Washington County, and in early February I observed many robins flying toward > a plantation of spruce and pine trees, located where Pioneer Road met county > road 75. A few days later I started counting the robins coming to the area > and counted 900, but the robins just kept coming. On February 15, 2010, I > started counting at 4:30 p.m., about one hour before sunset. It was cloudy > with a fairly stiff breeze out of the northwest. The robins flew in one at a > time and then in groups of up to about 30 birds. By one hour after sunset the > stream of robins had subsided, but by then I had counted 2,300 birds. I know > we have had an increase of American Robins wintering in Minnesota, but I did > not ever expect to see so many at one time. > > The number seems exorbitant, but I firmly believe it is a minimum, > as when estimating the size of some groups flying in, I was careful to use my > lower estimate. All of the birds came in from the west, where the > Mississippi River is less than a half-mile away. Also many came from the open > water areas at the bottom of the Aggregate Industries limestone quarry less > than one fifth of a mile west of the conifers. > > The plantation was never thinned, so the trees are very dense. The > spruce trees are all less than 20 feet tall and the pines less than 30 feet. > The arriving robins would first perch in surrounding deciduous trees before > descending into the conifers. I found it amazing to observe so many robins > disappearing in only 1.5 acres (0.6 hectares) of densely growing conifers. > > Being curious about when the robins left their nightly roost site, > on 22 February, 2010, I set up my vigil. The first robins left one half hour > before sunrise, being cloudy it was quite dark at that time. Ten minutes > later there was a fairly steady stream of birds flying out to the west. One > hour and fifteen minutes after sunrise the last of the observed robins left. > On leaving the birds did not first perch in a surrounding deciduous tree, > they just flew directly away. > > Tom Bell > > 5868 Pioneer Rd. So. > > Grey Cloud Island, MN 55071 > > Tom Bell > Grey Cloud Island > 5868 Pioneer Rd. S. > St. Paul Park, MN 55071 > 651 459-4150 > > > > > > ---- > Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net > Archives: http://lists.umn.edu/archives/mou-net.html ---- Join or Leave mou-net: http://lists.umn.edu/cgi-bin/wa?SUBED1=mou-net Archives: http://lists.umn.edu/archives/mou-net.html
