Alan's suggestion is interesting and I know of no evidence to support or refute it- do such solar flares affect the earth's magnetic force lines near ground level? The following is a more conventional explanation-lecture (sorry) collected from many years of observations by many ornithologists. The reasons why these SW species are moving at all now should be considered first- some are migrating and perhaps misoriented, some are juvs that may be dispersing from their natal regions and some may be moving away from areas of drought or food crop failure. Prof Ian Mclaren, who has studied vagrancy of migrants caused by weather systems in the Canadian Maritimes states that the best way out of a bad situation for a passerine migrant (esp those over the ocean) is using the tailwind to maximize time aloft to find land. Look at the train and tailwind that can guide these SW species. The train is the jet stream which has been dipping into the SW then moving north over the Upper Midwest since late October- this pattern is persisting- http://www.weatherimages.org/data/imag192.html Think of the jet as the guiding force providing the path that the weather systems (lows) follow. If a wandering, unoriented bird gets caught in the east side of such a low (remember the the circulation around a low is counter-clockwise) in the SW it will experience a continuous S or SW flow of surface winds as it enjoys a tailwind and could easily make it to Wisconsin. Here's the forecast map for Wednesday evening- note how the low is moving west of Wisconsin http://weather.rap.ucar.edu/progs/index.php?prog=48 The 2006? Cave Swallow invasion which brought dozens of birds to the Lk Michigan shoreline was similar as a very strong low moved north from the southern Gr Plains and Texas over Minnesota giving us very strong W-SW winds. Lows that move south and east of the Midwest will take Cave Swallows east to the Coast which happens every year- a more common Nov. pattern; when the jet moves north taking lows west of Wisconsin we can expect more vagrants. A cold November generally means a jet that moves east south of the Midwest allowing cold air to move in from the north. The weather patterns now are very similar to those of fall of 2000; here's a summary of that fall from Surfbirds- scroll completely through each page- http://www.surfbirds.com/Rarities/usoct.html http://www.surfbirds.com/Rarities/usnov2.html November is predicted to be warm meaning that the jet should continue a similar pattern favorable for SW vagrancy. John I Mke ----- Original Message ----- From: "Alan Stankevitz" <alan@xxxxxxxxxxxxxxxxxx> To: wisbirdn@xxxxxxxxxxxxx Sent: Sunday, November 6, 2011 8:37:22 PM Subject: [wisb] No sighting -- Speculation on Southwestern U.S. species birds in WI and nearby states Unless I have missed the post(s) and I apologize if I did, has anyone discussed how all of these Southwestern U.S. species have ended up in WI? I have a theory and would like to know what others think. It could just be a coincidence, but the timing seems right that the geomagnetic storm that occurred during the night of Oct. 24th has coincided with the arrival of the Southwestern species of birds reported in WI and other nearby states. It is been well documented that some birds migrate using the earth's geomagnetic field. It certainly seems plausible that this "fallout" of Southwestern species of birds could have been caused by the geomagnetic storm messing with the guidance systems of birds. Alan Stankevitz #################### You received this email because you are subscribed to the Wisconsin Birding Network (Wisbirdn). To UNSUBSCRIBE or SUBSCRIBE, use the Wisbirdn web interface at: //www.freelists.org/list/wisbirdn To set DIGEST or VACATION modes, use the Wisbirdn web interface at: //www.freelists.org/list/wisbirdn Visit Wisbirdn ARCHIVES at: //www.freelists.org/archives/wisbirdn #################### You received this email because you are subscribed to the Wisconsin Birding Network (Wisbirdn). To UNSUBSCRIBE or SUBSCRIBE, use the Wisbirdn web interface at: //www.freelists.org/list/wisbirdn To set DIGEST or VACATION modes, use the Wisbirdn web interface at: //www.freelists.org/list/wisbirdn Visit Wisbirdn ARCHIVES at: //www.freelists.org/archives/wisbirdn