call in association with a hunched wing-spreading display (Short 1974). Drumming is variable (fast or slow) in long, even rolls (Farrand 1983; Goggans 1989). Drumming described as coming in 2-second bursts that taper off at end, at intervals of 30-40 seconds, suggestive of pileated woodpeckers (DRYOCOPUS PILEATUS); also gives single raps when nervous or about to roost (Kilham 1966). See Short (1974) and Anonymous (1992) for descriptions of calls and drumming.
VOCALIZATIONS: See Barklow (1979), Klein (1985), McIntyre (1988), Miller (1988), Palmer (1962), Rummel and Goetzinger (1975), Sjolander and Agren (1972) for descriptions of vocalizations.