Banding birds allows for a unique opportunity to closely track and monitor bird populations.  Because migration is such a crucial and energetically stressful part of a bird's life, the impact migrations can have on overall populations is substantial.  Tracking the timing of a species migration can provide data about variations that may relate to significant conservation concerns such as global warming.  In this context, consistent long-term data sets such as Powdermill's can be invaluable.  In the table below, species totals are given week-by-week from August 7 through November.  While migration patterns in 2003 were not unusual in any way when compared to long term trends, it is interesting to speculate on a few patterns from this fall's data.  In species such as American Redstart (AMRE), Cedar Waxwing, and Eastern Towhee (to name a few), the weekly totals tend to reflect shifts in movements of different populations of birds.  Fairly high weekly totals for AMRE, for example, during the first weeks of August, most likely represent the tail end of the post-breeding dispersal of resident breeding birds, which begin moving away from their forested breeding territories in July.  At the end of August, numbers of AMRE fell into single digits until the onset of "true" passage migrants occurred two weeks later during September.   Of course, the table below also provides many interesting comparisons in the timing of fall migration across species. As always, we encourage other banders and researchers who are interested in working with us in utilizing any of our data for more comprehensive and/or comparative analyses to feel free to contact mulvipnr@westol.com.