) ) 38 Short Communications Vol. 26, No. 1 J Raptor Res. 26(l):38-39 © 1992 The Raptor Research Foundation, Inc. Greater Yellow-headed Vulture {Cathartes melambrotus Locates Food by Olfaction Gary R. Graves Department of Vertebrate Zoology National Museum ofNatural History, , DC Smithsonian Institution, Washington, 20560 Turkey Vultures Cathartes aura) and Lesser Yellow- (6-8 m) was exceedingly dense, the carcass could not be ( headed Vultures Cathartes burrovianus have acute senses observed from the air. Presumably, the vulture landed on ( ) m of smell (Stager 1964, Houston 1986, 1988). Although the the trail and approached the carcass, some 10 from the olfactory capacities ofthe Greater Yellow-headed Vulture trail edge, on foot. (C. melambrotus are unknown, they are thought to be On another occasion, a pair of Greater Yellow-headed similar to those of its congeners (Houston 1988). Here I Vultures discovered a cache of day-old flesh from a large report observations that strongly suggest the use of smell museum specimen of the Brazilian Porcupine Coendou ( m by this species to locate carrion. Collectively, these data prehensilis) that had been dumped 200 from camp at indicate that acute olfaction is a shared derived character the end ofa poorly marked trail. The flesh had been partly of Cathartes within the Cathartidae, as reflected by the covered with leaf litter and was further obscured from large olfactory lobe (Bangs 1964, pers. observation). view by the canopy oftall (30 m) seasonally flooded forest. I made daily observations of vulture abundance and The cache was difficult for me to visually locate when I behavior on the east bank of the Rio Xingu (3°39'S returned to the area, and in all likelihood, could not have 52°22'W), 52 km SSW of Altamira, Para, Brazil (Graves been observed by vultures flying above the canopy. In both and Zusi 1990), from 14 August to 29 September 1986. cases, Greater Yellow-headed Vultures presumably de- Evidence of olfaction in the Greater Yellow-headed Vul- tected the carrion by scent alone. Turkey Vultures were ture was observed in two instances. relatively rare near camp and were never observed at car- In the first instance, I flushed an adult vulture from the rion in the forest. carcass of a White-faced Tree Rat Echimys chrysurus) on Cathartes spp. and Black Vultures Coragyps atratus) ( ( the ground in a dense stand ofbamboo in terra firme forest appear to partially segregate by habitat along the lower several km from the river. The startled vulture clumsily Rio Xingu. Away from towns, agricultural clearings, and zigzagged on foot through the bamboo culms, took flight rivers, the Greater Yellow-headed Vulture was the prev- from the trail cut through the bamboo, and flew to an alent vulture ofpristine forest, outnumbering other species emergent tree. The carcass, which appeared to be less than by an order ofmagnitude (Table 1). Black Vultures, which a day old, was almost completely consumed; only the skin have poorly developed olfactory senses and rely on vision from the rat’s head and back and the attached tail re- to locate food, scavenged beached fish on sandbars near mained. Adult E. chrysurus weigh from 415-890 g (Em- camp and were not observed away from the river in un- mons and Feer 1990). Because the canopy of the bamboo broken forest. The few King Vultures (Sarcoramphuspapa) recorded during the study were observed soaring at great heights near the braided channel of the river, Table 1. Relative abundance of vultures on the lower — Rio Xingu, Para, Brazil, from 14 August to 29 September Resumen. Presentamos evidencias que sugieren que los 1986. buitres de la especie Cathartes melambrotus usan el olfato para localizar sus alimentos. En la floresta de espesura Number Largest continua, a lo largo del bajo Rio Xingu, Para, Brasil, esta of Days Daily especie excede en numero a otras especies de buitres en Species Observed Total Total una magnitud significativa. [Traduccion de Eudoxio Paredes-Ruiz] Greater Yellow-headed Vulture 31 6 101 Acknowledgments Turkey Vulture 7 1 7 Field work was facilitated and supported by the Aca- Black Vulture 6 5 18 demia Brasileira de Ciencias, through a grant from Elec- King Vulture 5 4 8 tronorte administered by Paulo Vanzolini. Transportation March 1992 Short Communications 39 to and from Brazil was provided by the Smithsonian’s Emmons, L.H. and F. Feer. 1990. Neotropical rain- Neotropical Lowland Research Program. forest mammals: a field guide. University of Chicago I thank Mike Carleton, Louise Emmons, Linda Gor- Press, Chicago, IL. don, and Richard Zusi for assistance on the Xingu, Van- Graves, G.R. and R.L. Zusi. 1990. Avian body weights zolini and Bea Ribeiro for providing logistical support on the Xingu and in Sao Paulo, and Floyd Hayes, David from the lower Rio Xingu, Brazil. Bull. Br. Ornithol. Club 110:20-25. Houston and Patricia Rabenold for comments on the manuscript. Houston, D.C. 1986. Scavenging efficiency of Turkey Vultures in tropical forest. Condor 88:318-323. Literature Cited 1988. Competition for food between Neotrop- . Bangs, B.G. 1964. The nasal organs of the Black and ical vultures in forest. Ibis 130:402-417. Turkey vultures: a comparative study of the cathartid Stager, K.E. 1964. The roleofolfaction in food location species Coragyps atratus atratus and Cathartes aura sep- by the Turkey Vulture. LosAngeles County Mus. Contr. tentrionalis (with notes on Cathartes aura jalklandica, Set. 81:1-63. Pseudogyps bengalensis and Neophron percnopterus). J. Morph. 115:153-184. Received 11 October 1991; accepted 3 December 1991