The Northern Shrike is very similar to the Loggerhead Shrike but is larger with a black mask that does not extend across the top of the bill, a paler gray overall color and faintly barred underparts. Immatures are browner than immature Loggerheads. Northern Mockingbirds have slimmer bills and lack a black mask.
Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.