The Northern Harrier (Circus cyaneus) is a widespread raptor that preys mainly upon small mammals and, to a lesser extent, birds. Most published accounts of harrier food habits report the majority of avian prey items are passerines with few large (> 500 g) birds taken. In fall 1999, I observed a Northern Harrier that appeared to have attacked and killed a White-faced Ibis (Plegadis chihi) foraging in a playa wetland in Meade County, Kansas. Field observations of the harrier, in addition to physical evidence, suggest the attack was on an apparently healthy individual that did not have any obvious physical deformities. Northern Harriers appear to attack and kill White-faced Ibis and may prey on large birds more often than reported previously.