Among standard measurements, the wing chord may vary from in males and from in females. Wing chord is generally commensurate with body mass, averaging largest in the heavier hawks of eastern North Dakota, where males averaged and females , and in Wisconsin, where males averaged and females (those from Cape May also being similar to those two samples). However, smaller, more westerly hawks such as those in the Goshute mountains, where males measured at a mean of and females at a mean of , and in British Columbia, with a male mean of and female mean of , were proportionately longer winged relative to their other body proportions. The tail of males may vary from and that of females at , consistently over in females and averaging under in males. In tarsus length, males may vary from , with an average of in museum specimens, and females from , with an average of in museum specimens. The culmen may measure from in males, averaging about , and from in females, averaging about . The hallux claw, the enlarged rear talon featured on nearly all accipitrids, may measure from in males, averaging about , and from in females, averaging about . The footpad of Cooper's hawks may measure in males , averaging in 42, and in females , averaging in 23. For unclear reasons, the smaller-bodied hawks found in British Columbia were found to be proportionately larger footed, median toe length between sexes of , than the larger bodied ones in Wisconsin.