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Bob et al. You're right, birds do need to be in the air first, and on that note, when they are, and weather shuts them down, it's usually apparent on the radar (in fact, I think it's the best remotely sensed predictor of fallout conditions). The area you birded has had thunderstorms over the last three nights, and hasn't shown significant migration (on the radar, at least) since the morning of the 16th. You make another excellent point, and one that I was just talking about yesterday, with Sid Gauthreaux from the Clemson Radar Ornithology lab (http://virtual.clemson.edu/groups/birdrad/). You saw shorebirds! Shorebirds, as you know, are strong fliers and will likely migrate in less-than-optimal conditions AND be less prone to shifting by winds AND (in some species especially) will migrate during the day so may be underestimated by radar alone. When looking at the radar it's important to remember that what we're seeing is a mix of ALL birds that are migrating at night (waders, rails, shorebirds, passerines, owls, and even a few raptors). That has to be taken into consideration when heading out in the morning to look for birds. The other point that Sid was making yesterday, is that small passerines (warblers, etc.) will likely be the ones most displaced by strong winds- so that when you do see strong directional flow on the radar (like birds being blown to the coast, for instance) the result is usually a good mix of birds that birders are "expecting" during migration. This topic is fascinating- and one that is only just being explored using radar and ground-truthing. I really hope you will all consider contributing your observations to the comments section of badbirdz-reloaded (http://badbirdz2.wordpress.com) so that we can begin to correlate the images with actual conditions in the field. Good birding- and thanks again to Bob for posting his observations and posing a great question. David On 9/19/07, Robert Wallace <[log in to unmask]> wrote: > > David - with the hope that the rains from Tue night and Wed morning would > indeed cause a fallout along the east coast, I hit a number of parks/migrant > traps in Volusia County today - Tomoka SP, Riverbend Park, Central Park, and > Deleon Springs, with the grand total of 1 Redstart and 1 Red-eyed Vireo at > each location, plus 1 Parula, 2 Ovenbirds, 1 Bt Blue Warbler, 1 > Yellow-throated Warbler and a Scarlet Tanager thrown in. Not exactly a > banner fallout. The constant rains all day I am sure limited activity - > there was little sign of any bird life. All of the numbers and species seen > the last 2 days at Fort George and Timucuan, which I thought would be > indicative of activity today, were non-existant. The only significant > numbers of migrants were shorebirds, at the Flagler Sod Fields off SR 100, > and the sod fields off Pioneer Trail in New Smyrna Beach - where there were > Killdeer, quite a few Black-bellied Plovers, Lesser Yellowlegs, 1 Golden > Plover (at Flagler), some Pectorals, Leasts, and 1 Bairds Sandpiper (at > Pioneer). Pretty slim pickings overall. > > It is my opinion that heavy precipitation is not necessarily a good > indicator of passerine fallout - the birds need to be in the air first > (certainly shorebirds are easier to find in the open fields). The birds > seen at Ft George were moving south with the cold front, and put down when > they first encountered the rain of this system. After 2 days of rain, there > were no new birds moving in, at least at Daytona today. So why did Miami > have such a great fallout? What weather precipitated that? > > I would appreciate hearing other's opinions as to precursors to predicting > a good fallout during fall migration. Can you look at Sunday and Monday's > flights on the NE coast, and see them in the air first? > > Glad to be home and dry, > Bob Wallace > Alachua > > ----- Original Message ---- > From: David La Puma <[log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]> > > > To: [log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]> > Sent: Wednesday, September 19, 2007 9:19:37 PM > Subject: [FLBIRDS] Birds and weather over Florida > > The low pressure system causing all the precipitation and variable winds > across the state could mean good birding conditions for some locations. > The > Jacksonville radar was showing heavy migration just after sunset, but the > flow of birds is currently being shut down by heavy showers and > thunderstorms. This could lead to local fallout conditions wherever the > heavy precipitation is taking place. The panhandle shows birds launching > into the Gulf, while the west coast radar is showing birds moving south > along the coast. Over southeast Florida, where winds are out of the > northwest, birds are moving at lower densities, yet toward the east coast, > which usually means good birding conditions for east coast migrant traps > as > birds overshoot the coast and have to correct themselves come morning. > It's > still very early in the night, so check the radar loop in the AM to see > how > it all plays out. > > Good Birding > > David > > http://badbirdz2.wordpress.com > > -- > ____________________________________________________ > David A. La Puma > Ph.D. Candidate > Dept. of Ecology, Evolution, & Natural Resources > Plant Physiology Building > 1 College Farm Road > Rutgers University > New Brunswick, NJ 08901-1582 > > "most policies are really questions masquerading as answers" (L. > Gunderson) > > email 1: [log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]> > email 2: [log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]> > > websites: > http://www.woodcreeper.com > http://badbirdz2.wordpress.com > > my photos: > http://www.flickr.com/photos/woodcreeper > > Lockwood lab: > http://rci.rutgers.edu/~jlockwoo <http://rci.rutgers.edu/%7Ejlockwoo> > > > ____________________________________________________________________________ > FLORIDABIRDS-L Listserv mailing list information: > Member photos I: http://bkpass.tripod.com/floridabirds.htm > Member photos II: see connection on photos I > For archives: http://lists.ufl.edu/archives/floridabirds-l.html > Set nomail: [log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]>Message: Set floridabirds-L nomail > Listowner: [log in to unmask]<https://mail.google.com/mail?view=cm&tf=0&[log in to unmask]> > > -- ____________________________________________________ David A. La Puma Ph.D. Candidate Dept. of Ecology, Evolution, & Natural Resources Plant Physiology Building 1 College Farm Road Rutgers University New Brunswick, NJ 08901-1582 "most policies are really questions masquerading as answers" (L. Gunderson) email 1: [log in to unmask] email 2: [log in to unmask] websites: http://www.woodcreeper.com http://badbirdz2.wordpress.com my photos: http://www.flickr.com/photos/woodcreeper Lockwood lab: http://rci.rutgers.edu/~jlockwoo ____________________________________________________________________________ FLORIDABIRDS-L Listserv mailing list information: Member photos I: http://bkpass.tripod.com/floridabirds.htm Member photos II: see connection on photos I For archives: http://lists.ufl.edu/archives/floridabirds-l.html Set nomail: [log in to unmask] Message: Set floridabirds-L nomail Listowner: [log in to unmask]