Notes on the Vocalizations of the Mexican Chickadee

Abstract

The natural history of the Mexican Chickadee (Parus sclateri), which nests in the United States only in the upper reaches of mountain ranges in southeastern Ar-izona and adjacent New Mexico, has received scant attention. Although this species was considered by Snow (1956) to be closely allied to the Black-capped and Carolina chickadees (P. atricapillus and P. cm-o-linensis), descriptions (e.g., Peterson 1961:212) suggest that its vocalizations are aberrant within the group. R. T. Peterson (quoted by Brandt 1951:601) observed that " instead of clear whistling notes, the bird sings a nasal ' dzay dzee,' so low in pitch that this seems to belong to a much larger bird and is not chickadee-like at all " . J. T. Marshall (in Pough 1957: 195) commented on vari-ations in the songs, characterizing a common version as " ka-breee, ka-breee, ka-breee. " He noted that the voice of P. sclateri was " quite different " from that of the Mountain Chickadee (P, gambeli). In view of these apparent departures from the norm for the North Amer-ican gray-backed chickadees, we endeavored to obtain tape recordings of the vocalizations of the Mexican Chickadee during the breeding season. METHODS Visits to the Chiricahua Mountains of southeastern Arizona were made by Dixon, 25-28 April 1968, and by both of us, 15-19 April 19?2. These dates may be compared to that for the earliest set of chickadee eggs from this locality (10 May) reported by Brandt (1951:673). On the first visit, when we were stopped by persisting snowbanks, chickadees were inconspic-uous and few recordings were obtained. In 1972 we played back tape-recorded vocalizations to the chick-adees, and recorded the responses of individuals oc-cupying five contiguous territories. Most of the record-ings were made at Rustler Park, 2,590 m elevation, 17 and 19 April 1972 using a Nagra III BH recorder at 19 cm/s. The sounds were analyzed on a Kay Electric Co. Sona-Graph, Model 661 A, using a wide band-pass fil-ter. After some 70 representative sonograms were made, we listened to the tapes again to review aspects of the birds' encounters. In addition, we reviewed tape recordings of Mexican Chickadee vocalizations made in the Chiricahuas in May 1977, by investigators from Cornell University. RESULTS AND DISCUSSION