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We discuss select imprecise and untenable natural history information about migration, urban habitat use, and diet presented in the technical literature about Accipiter hawks in North America. We focus primarily on challenging the claim that Sharp-shinned Hawks (Accipiter striatus) are more frequent predators of House Sparrows (Passer domesticus) than are Cooper's Hawks (A. cooperii). We urge scientists to be cognizant of the ever-changing dynamics of the predatory behavior, nesting, and migration ecology of Sharp-shinned and Cooper's hawks due to anthropogenic factors, features that are in constant flux and may not be well tracked long term or apply to the entire distributional ranges of these 2 species. Discutimos acerca de informaciones de historia natural imprecisa e insostenible acerca de la migración, del uso de hábitat urbano y la dieta presentada en la literatura técnica sobre gavilanes Accipiter en América del Norte. Principalmente nos enfocamos en cuestionar la afirmación de que el gavilán americano (Accipiter striatus) es un depredador más frecuente de gorrión común (Passer domesticus) que del gavilán de Cooper (A. cooperii). Exhortamos a los científicos a reconocer las dinámicas siempre cambiantes de comportamientos de depredación, anidamiento y ecología migratoria del gavilán americano y del gavilán de Cooper debido a factores antropogénicos, aspectos que están en flujo constante y podrían no tener buen seguimiento a largo plazo o no aplicar al rango de distribución completo de esas especies. Palabras clave: depredación, dieta, gorrión común, migración, urbanización. [ABSTRACT FROM AUTHOR]

House Sparrow (Passer domesticus) populations declined across much of their global range in the late 20th century. Most research examining this decline is conducted in the species' native European range, but Europe encompasses a small portion of the species' current distribution. House Sparrow population trends in the United States and Canada, and the potential mechanisms driving these trends, remain relatively unexplored. We use 21 years of data from Project FeederWatch, a large-scale citizen science project, to investigate House Sparrow population trends in North America. We found winter flocks in urbanized areas were larger than flocks in rural areas, with widespread spatial heterogeneity in local population trends. Despite greater abundance in developed areas, House Sparrow populations declined in developed areas from 1995 to 2016 while remaining stable in rural areas. House Sparrow population declines coincide with an increase in populations and expansion of the winter distributions of Accipiter hawks, which are known predators of House Sparrows. However, we do not find a direct connection between the presence of Accipiter hawks at count sites and House Sparrow population declines in winter. These results expand our knowledge of widespread House Sparrow declines to North America and provide context for continuing research on House Sparrow declines in the introduced range. [ABSTRACT FROM AUTHOR]