As we had hoped, the number of night calls reached new highs for the spring in the first two weeks of April. Favorable calm or south winds produced from 100 to 200 calls each night. See attached graphs.
As a comparison, we have a recorder at our home in the city of Austin. It’s a relatively quiet neighborhood at night but surrounded by trees. And the control is 10 miles west of town in the middle of a very quiet pasture. From March 1 to April 17, our home recorder had 1796 calls and the quiet pasture site has 2973 calls which is about 50% more. Now some might not but I consider this a great success for our home recorder. Here we are in the middle of a big city. Not bad. I don’t think anybody should not record just because they are in an urban area. However, if I re-plot these as percent of flight, then the quieter location does seem to have smoother data. In the sense that the percent of each group does not jump around as much from day to day. I have almost concluded that it’s not the general noise of the Austin urban area that reduces detection as much as it is the surrounding close tree tops which on any windy night the leaf noise overwhelms the recorder for a good part of the time. Keeping away from trees is always good, of course. The next 3 weeks are considered by birders as the peak weeks for migration through Texas. Already, April 17th gave us a 440 call night on our quiet remote station just west of Austin. -Mike Farmer equipment Mic – Oldbird 21c Software – Oldbird tseep, thrush, GlassOFire, Raven Pro -- NFC-L List Info: http://www.NortheastBirding.com/NFC_WELCOME http://www.NortheastBirding.com/NFC_RULES http://www.NortheastBirding.com/NFC-L_SubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/[email protected]/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NFC-L 3) http://birdingonthe.net/mailinglists/NFCL.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
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