Analyzing Rebanded Birds From the beginning of the banding
program to the end of the calendar year 1967, when a bird was
rebanded, the original band number was used on all banding
records. In 1968, provision was made for printing TWO band
numbers on the Report-to-Bander: the original number, and the
number actually reported by the finder. However, the band number
entered in the statistical record in the recovery file is the
number reported by the finder. Banders requesting data from the
Bird Banding Laboratory files are warned that species that
outlive their bands can have more than one band number. There
may be more than one encounter of the same bird under different
band numbers. For recaptured birds, records should be
individually checked and corrected in order to accurately
estimate return and recovery rates, age ratios and mortality and
survival rates. The data for the original banding (age-sex,
status, location, date), and the permit number of the original
bander are available from the Recovery Statisti