38 SHORT COMMUNICATIONS VOL. 26, NO. 1 j RaptorRes. 26(1):38-39 ¸ 1992 The Raptor ResearchFoundation, Inc.

GREATER YELLOW-HEADED VULTURE ( Cathartesrnelarnbrotus) LOCATES FOOD BY OLFACTION

GARY R. GRAVES Departmentof VertebrateZoology, National Museum of Natural History, SmithsonianInstitution, Washington, DC 20560

Turkey Vultures (Cathartesaura) and LesserYellow- (6-8 m) was exceedinglydense, the carcasscould not be headed Vultures (Cathartesburrovianus) have acute senses observedfrom the air. Presumably,the vulture landedon of smell(Stager 1964, Houston1986, 1988). Althoughthe the trail and approachedthe carcass,some 10 m from the olfactorycapacities of the Greater Yellow-headedVulture trail edge, on foot. (C. melambrotus)are unknown, they are thought to be On another occasion,a pair of Greater Yellow-headed similar to thoseof its congeners(Houston 1988). Here I Vultures discovereda cacheof day-old flesh from a large report observationsthat stronglysuggest the use of smell museum specimenof the Brazilian Porcupine (Coendou by this speciesto locatecarrion. Collectively,these data prehensilis)that had been dumped200 m from camp at indicate that acute olfaction is a shared derived character the end of a poorly marked trail. The fleshhad beenpartly of Catharteswithin the Cathartidae, as reflectedby the covered with leaf litter and was further obscured from large olfactory lobe (Bangs 1964, pers. observation). view by the canopyof tall (30 m) seasonallyflooded forest. I made daily observationsof vulture abundanceand The cachewas difficult for me to visually locatewhen I behavior on the east bank of the Rio Xingu (3ø39'S returned to the area, and in all likelihood, could not have 52ø22'W), 52 km SSW of Altamira, Patti, Brazil (Graves beenobserved by vulturesflying abovethe canopy.In both and Zusi 1990), from 14 August to 29 September 1986. cases,Greater Yellow-headed Vultures presumablyde- Evidence of olfaction in the Greater Yellow-headed Vul- tectedthe carrion by scentalone. Turkey Vultures were ture was observed in two instances. relatively rare near camp and were never observedat car- In the first instance,I flushed an adult vulture from the rion in the forest. carcassof a White-facedTree Rat (Echimyschrysurus) on Cathartesspp. and Black Vultures (Coragypsatratus) the groundin a densestand of bambooin terra firme forest appear to partially segregateby habitat along the lower several km from the river. The startled vulture clumsily Rio Xingu. Away from towns, agricultural clearings,and mgzaggedon foot throughthe bambooculms, took flight rivers, the Greater Yellow-headed Vulture was the prev- from the trail cut through the bamboo, and flew to an alent vulture of pristine forest,outnumbering other species emergenttree. The carcass,which appearedto be lessthan by an orderof magnitude(Table 1). BlackVultures, which a day old, was almostcompletely consumed; only the skin have poorly developedolfactory senses and rely on vision from the rat's head and back and the attached tail re- to locate food, scavengedbeached fish on sandbarsnear mained. Adult E. chrysurusweigh from 415-890 g (Em- camp and were not observedaway from the river in un- mons and Feet 1990). Becausethe canopyof the bamboo brokenforest. The few King Vultures(Sarcorarnphuspapa) recordedduring the study were observedsoaring at great heights near the braided channel of the river. Table 1. Relative abundance of vultures on the lower Rio Xingu, Parfi, Brazil, from 14 Augustto 29 September RESUMEN.--Presentamosevidencias que sugierenque los 1986. buitres de la especieCathartes rnelambrotus usan el olfato para localizar sus alimentos. En la floresta de espesura NUMBER LARGEST continua,a lo largo del bajo Rio Xingu, Parfi, Brasil, esta OF DAYS DAILY especieexcede en nfimero a otras especiesde buitres en SPECIES OBSERVED TOTAL TOTAL una magnitud significativa. [Traducci6n de Eudoxio Paredes-Ruiz] Greater Yellow-headed Vulture 31 6 101 ACKNOWLEDGMENTS Turkey Vulture 7 1 7 Black Vulture 6 5 18 Field work was facilitated and supportedby the Aca- demia Brasileira de Ci•ncias, through a grant from Elec- King Vulture 5 4 8 tronorteadministered by PauloVanzolini. Transportation MARCH 1992 SHORT COMMUNICATIONS 39 to and from Brazil was provided by the Smithsonian's EMMONS,L.H. ANDF. FEER.1990. Neotropicalrain- NeotropicalLowland ResearchProgram. forestmammals: a field guide. University of Chicago I thank Mike Carleton, Louise Emmons, Linda Gor- Press,Chicago, IL. don, and Richard Zusi for assistanceon the Xingu, Van- zolini and Bea Ribeiro for providinglogistical support on GRAVES,G.R. AND R.L. ZusI. 1990. Avianbody weights the Xingu and in S5o 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. Scavengingefficiency of Turkey Vultures in tropical forest.Condor 88:318-323. LITERATURE CITED 1988. Competitionfor foodbetween Neotrop- BANGS,B.G. 1964. The nasal organs of the Black and ical vultures in forest. Ibis 130:402-417. Turkey vultures:a comparativestudy of the cathartid STAGER,K.E. 1964. The role ofolfaction in food location speciesCoragyps atratus atratus and Cathartesaura sep- bythe Turkey Vulture. Los Angeles County Mus. Contr. tentrionalis(with notes on Cathartesaura falklandica, Sci. 81:1-63. Pseudogypsbengalensis and Neophronpercnopterus). J. Morph. 115:153-184. Received11 October1991; accepted3 December1991