D. Bystrak C.S. Robbins R.M. Patterson David M. Bird Reed Bowman M.R. Fuller 1987 A 15-year summary of the BBS data suggests that continental numbers of American Kestrels have increased during 1966-1979. According to analyses of physiographic and state/province strata, some areas are largely responsible for the increase in the U.S. and southern Canada and that only in Illinois and Arkansas have kestrels declined. BBS data are too few in Florida to detect trends concerning F. s. paulus. Surveying on special Raptor Routes, on which volunteers looked specifically for raptors while retracing their BBS route, did not significantly increase the kestrel counts, but did improve detection rates. application/pdf en Raptor Research Foundation, Inc. and MacDonald Raptor Research Centre of McGill University Trends in American kestrel counts from the North American Breeding Bird Survey chapter