The Condor92349-753 0 The Cooper Omitholo&il Society 1990

TAXONOMIC STATUS OF THE RUFOUS-BELLIED CHACHALACA (ORTALIS WAGLERI)’

RICHARD C. BANKS BiologicalSurvey Group, National EcologyResearch Center, U.S. Fish and Wildrife Service, National Museumof Natural History Washington,DC 20560

Abstract. The Rufous-bellied Chachalaca,Ortalis wagleri, of northwestern was merged with the morphologicallydifferent West Mexican Chachalaca,Ortalis poliocephala, on the basis of hybrids taken in the vicinity of , (Moore and Medina 1957). Eight specimens from that vicinity vary in appearance chronologically, from an individual similar to wagleriin 1892 through skins appearingto be F, hybrids in 1955 to birds nearly indistinguishable from poliocephala in 1961. There is no other evidence of contact between the two forms. This is deemed insufficient evidence for considering the forms conspecific,and I recommend that Ortaliswagleri be restoredto the statusof species. Key words: Rufous-belliedChachalaca; Wagler s’ Chachalaca;Ortalis wagleri; WestMex- ican Chachalaca;Ortalis poliocephala;Mexico; hybridization:taxonomy.

INTRODUCTION Amadon (1973) suggestedthat the two forms Chachalacas(Or&is spp.) are economically im- might actually be distinct. portant game species throughout their collective The genus Ortalis is a difficult group, consist- range in Latin America. Like their larger and ing of 1O-l 2 very similar species,mostly mono- more showy relatives in the family Cracidae, the typic and mostly allopatric. Those that overlap guans and curassows, many chachalacas are suf- geographicallygenerally do so in limited fashion, fering from reduced population levels because of at only one or a few localities (Delacour and overexploitation and habitat loss; several species Amadon 1973). Very little hybridization is known in the family are considered endangered.Despite (Vuilleumier 1965), despite the overall similar- this, many aspectsof the biology of the cracids ities among all the species.It has even been sug- are poorly known-including their taxonomic and gestedthat the entire genus constitutes a super- evolutionary relationships. species (Amadon in Mayr and Short 1970). From the time of its description in 1867 until Difficulties of classification in the genus are in- 1957, the Rufous-bellied or Wagler’s Chacha- dicated by the AOU (1983), in which notes pre- laca, Ortalis wagleri, of northwestern Mexico was senting alternative taxonomic treatments are considereda distinct species.The more southern given for each of the four species listed. One West Mexican Chachalaca, 0. poliocephala,sim- changein the taxonomy of the Central American ilarly was considered distinct for most of its group has already been made, namely the ele- named existence,although from about 1934 until vation of 0. leucogastrato the specieslevel (AOU 1953 it was ranked as a subspeciesof the Plain 1985). Chachalaca, 0. v&da (Griscom 1934, Hellmayr DIFFERENCES BETWEEN 0. WAGLERZ and Conover 1942, Ridgway and Friedmann AND 0. POLIOCEPHALA 1946, Wagner 1953). Just when the specific dis- tinction ofpoliocephala was reconfirmed, wagleri Ortalis wagleri is distinctive in the genus in hav- was merged into it as a subspecies(Moore and ing the abdomen and the tips of the tail feathers Medina 19 5 7). This taxonomic statuswas main- rich chestnut. The speciespoliocephala, on the tained by Vaurie (1965, 1968) and is reflected other hand, is whitish or grayish white on the by the AOU (1983), although Delacour and underparts and tail tips, although most individ- uals have a wash of buff or rufous on the thighs or abdomen and on the tips of the rectrices.Even I Received12 January 1990. Final acceptance3 May though he treated these forms as conspecific, 1990. Vaurie (1965, p. 12) noted that they represent

[7491 750 RICHARD C. BANKS

[spectrograms]of wagleri from . . . show some similarity to the spectrogramsofpolioceph- ala but not very much.” Neither of these studies is definitive or convincing.

EVIDENCE FOR THE MERGER The evidence to support the merger of these two distinctive Mexican forms (Moore and Medina 1957) consisted of a small series of birds from the vicinity of Puerto Vallarta, Jalisco, near the border of Nayarit, that seem to be hybrids or intergrades. The earliest Puerto Vallarta speci- mens had been used to set the southern limit of wagleri at about the border of Nayarit and Ja- lisco. Aside from specimensfrom the Puerto Val- 0 1 I I I I larta area, there is a large gap in the documented KMS range of the two speciesfrom San Blas and Tepic, Nayarit, along the entire coastofJalisco to north- FIGURE 1. Map showingnearest documented lo- em Colima (Ridgway and Friedmann 1946). calitiesof Ortalis wagleri(dots) and 0. poliocephala (Note: Vaurie, 1965, p. 17, mentioned a tape of (triangles)in westernMexico. The hybrid areain the calls attributed to 0. wagleri made 34 miles vicinity of PuertoVallarta is indicatedby a square.An northeast of Puerto Vallarta, Jalisco. This ap- uncertainrecord is markedby ?; seeparenthetical note on p. 750. pearsto be in the valley of the Rio Ameca, about 30 miles northwest of Amatlan, Nayarit. Spec- trograms of those calls, however, were consid- the extremes of color variation in the genus. The ered very different from those of calls of wagleri two forms are similar in size, being the largest from farther north and were not similar to those members of the genus. In wagleri, the bare facial of calls of poliocephala. The identity of the bird skin around the eyes is blue, and the bare throat recorded, but apparently not collected, is in red, whereasinpoliocephala both the bare orbital doubt.) There seems to be a similar gap inland, and gular skin are “carmine” (Delacour and the nearest documented approach of the two Amadon 1973); these facial differencescould aid forms being between Amatlan, Nayarit, and in reproductive isolation. Whereas poliocephala Guadalajara, Jalisco (wagleri), and Autlan and is a bird of higher, moister broad-leaved decid- Los Masos, Jalisco (poliocephala), distances of uous forest in the major part of its range in south- about 150 km or 80 miles (Fig. 1, Vaurie 1965). em Mexico, wagleri, in northwestern Mexico, is If this separation is real, and not an artifact of a bird of much drier vegetation at lower eleva- incomplete collecting, it is as large as the gap tions. between any two neighboring populations in the There may also be vocal differences between North American range ofthe genus(Vaurie 1968, wagleri and poliocephala. Davis (1965) reported Delacour and Amadon 1973). on the voices of most members of the genus Or- Moore and Medina (1957) artificially closed talk and concluded that the vocalizations of wag- the distributional gap between the forms by new- leri and poliocephalawere more like one another ly naming the population of poliocephala from than either was like other species.However, the Colima 0. p. lajuelae, and by including some of differences were great enough so that he called the Puerto Vallarta specimensin the range of this them separate,but sibling, species.Vaurie (1965, subspecies.This new subspecieswas supposed p. 16) also discussedthe voices of these birds, to differ from more southern poliocephala by using Davis’s tapes. He felt that “the ‘song’ of being darker below, varying in the direction of wagieri . . . sounds very similar to that of poli- wagleri. Few later authors (e.g., Schaldach 1963) ocephala.” However, “the spectrograms pre- have recognized that subspecies,but even those pared from the tapes of wagleri did not confirm who have not recognizedit have followed Moore the very close similarity to poliocephala . . . .” and Medina (1957) in stating that the population Vaurie (1965, p. 17) went on to say that “five is intermediate between true poliocephala and TAXONOMY OF RUFOUS-BELLIED CHACHALACA 751 wugleri (Vaurie 1965, 1968). Delacour and Ama- other specimens were taken in the vicinity of don (1973) recognized the race deliberately to Puerto Vallarta in 1961 by Peter R. Grant and call attention to the supposedintergradation. Of are now in the Cowan Vertebrate Museum of the course,the redefinition of the range ofpolioceph- University of British Columbia (UBC). I have ala to include Puerto Vallarta establisheda point studied all eight of these specimens, along with of contact with wagleri, already stated to occur the series from within the recognized ranges of south to that area. Reiteration of the concept of poliocephala and wagleri in the U.S. National contact has reinforced the idea of intergradation Museum of Natural History (USNM) and all from Colima northward through Jalisco,and thus specimens in the AMNH. supported the proposal that the two different Descriptions of these eight specimens follow, forms represent a single species.This reinforce- as compared with “typical” 0. wugleri (USNM ment has taken place despite the lack of speci- 164438, male, Chacala, , ~011.by E. A. mens from the rest of the supposed intergrade Goldman, 24 Feb. 1899) and 0. poliocephala zone or additional material that is intermediate (USNM 185335, male, Papayo, Guerrero, ~011. morphologically. by E. W. Nelson and E. A. Goldman, 19 Apr. I cannot recognizethe existenceof a subspecies 1903). Becausethe forms are essentially identical of poliocephalafrom Colima northward through dorsally, only the ventral surfacesare compared. Jalisco that differs from southern birds by being AMNH 471460, female, Las Petias, Jalisco, darker below. Specimens of poliocephala in the ~011.by A. C. Butler, 7 Mar. 1892. Similar to southern part of the range have more color than wugleri ventrally but paler, the abdomen, cris- Moore and Medina (1957) and later authors sum, thighs, and tips of rectrices (except central, (Vaurie 1965, Delacour and Amadon 1973) have in each description) dark rufous rather than rich admitted. Many birds from Michoacan, Guer- chestnut. Lower neck and breast gray as in po- rero, and Oaxaca have extensive buff or rufous liocephala rather than brown as in wagleri. on the flanks, posterior lower parts and tail tips, AMNH 47 146 1, female, Bahia de Banderas, and match Colima birds in this respect. In my Jalisco,~011. by A. C. Butler, 8 Feb. 1892. Similar view, poliocephala is rather uniform throughout to 471460 ventrally but slightly paler, with a its range, with no trends or clines in color or size. bufi midventral streak on the abdomen. AMNH 2402 1 (Dwight toll.), male, Las Peiias, THE HYBRIDS Jalisco,~011. by P. I. Osbum, 16 Apr. 1909. Sim- Moore and Medina (1957) wrote about only three ilar to 47 146 1 but much paler below, entire ab- hybrids from the Puerto Vallarta area, although domen dark buff rather than rufous. they listed four specimens from the vicinity. DMNH 38485 (ARP 3867) male, Carboner- Vaurie (1965, p. 17) mentioned the same four. as, NE of El Pitillal, N of Puerto Vallarta, Jalisco, There were actually six specimensavailable from ~011.by A. R. Phillips, 23 Mar. 1955. Similar to that area at that time. Three specimens,two tak- AMNH 24021 but still paler below, sides of ab- en in 1892 and one in 1909, are in the American domen rufous but ventral midline pale creamy Museum of Natural History (AMNH). These buff. Rufous on posterior underparts and tail tip birds were all labeled wugleri, apparently until paler than in the three AMNH birds. “Concealed 1957, and were those responsible for the notion part of lower eyelid whitish, rest (and throat) rich that wagleri reachesits southern coastal limit in (purplish) rose-red.” northern Jalisco(Ridgway and Friedmann 1946). NMC 92599 (ARP 3868), female, locality and Both Moore and Medina (1957) and Vaurie date same as DMNH 38485. Similar to DMNH (1965, 1968) overlooked (or at least did not dis- 38485 (with which taken in same shot) but still cuss)two of these three birds. Three birds taken paler on posterior underparts, nearly like poli- by Allan R. Phillips in 1955 were the ones pri- ocephalu except for darker tail tips. Center of marily studied by Moore and Medina (1957). abdomen more bully than creamy. “Concealed Those birds were flat, salted skins at the time of part of lower eyelid whitish, rest (flesh) pink, that study (see fig. 1 in Moore and Medina 1957) throat deeper (more definitely pink).” but have since been prepared as study skins. One NMC 92600 (ARP 3818) male, Arroyo las is now in the Delaware Museum of Natural His- Estacas,Puerto Vallarta, Jalisco, ~011.by A. R. tory (DMNH) and two are in the National Mu- Phillips, 5 Mar. 1955. Similar topoliocephalu on seum of Natural Sciences(Canada) (NMC). Two breast. Posterior underparts similar to NMC 152 RICHARD C. BANKS

92599. Skin surrounding eye “and sidesofthroat that wagleri ever occurred in the coastal area pinkish, darker red above eye and at rear. Sides south of San Blas, Nayarit. There are still no of head dark plumbeous.” records of poliocephala in coastal Jalisco from UBC 10475, male, Puerto Vallarta, Jalisco, south of Puerto Vallarta, the nearest occurrences ~011.by P. R. Grant, 26 June 1961. UBC 10521, being inland at Autlln, Jalisco (Zimmerman and male, data same as 10475 except date 26 May Harry 195 1, reported as 0. vetula) and in Coli- 196 1. Both these birds are essentially pure po- ma. liocephala except that the tail tips, especially of Perhaps the birds from Puerto Vallarta do not 1052 1, are slightly darker. representa natural population, and therefore in- These specimensrepresent a chronological se- dicate nothing about the specificstatus of wagleri ries of hybrids or intergrades from 1892 to 196 1, and poliocephala. The fact that there are no re- ranging from birds most similar to wagleri to liable reports of chachalacasfor many kilometers those barely separable from pure poliocephala, in any direction from the environs of Puerto Val- from a single area (very close to a single locality) larta is consistentwith this hypothesis.Through- between the disjunct ranges of the two forms. out Mexico and Central America, chachalacas The bird taken in 1909 and the two taken in are frequently kept as pets or in a state of semido- 1955 from Carboneras are nearest to what one mestication (Griscom 1932; McClellan 1927; might envision as F, hybrids, whereasthe others Leopold 1959; R. W. Dickerman, pers. comm.). are much closer to one or the other of the pre- A striking bird like wagleriis perhapsparticularly sumed parental species. likely to be kept, as noted by McClellan for San Blas. It seemsnot too unlikely that both wagleri DISCUSSION and poliocephala might be, or have been, main- This series of hybrids, along with the distribu- tained in Puerto Vallarta, and that a mixed pop- tional information, can be interpreted in several ulation, or at least an occasional mixed clutch, ways. Perhaps these birds are from an interme- might result from birds that escapedor were re- diate, hybrid, and intergrading population as leased. The change through time from wagleri- suggestedby Moore and Medina (1957) indi- like to poliocephala-like birds may merely reflect cating sufficientgene flow so that the forms should a greater relative ease in obtaining birds from be considered conspecific. The observed range the south or a higher survival rate for polioceph- of variation might be expected in a hybrid zone, ala in conditions of captivity. but the chronological aspect of the series of hy- brids would not be expected.No specimensfrom CONCLUSION the north or south of the large distributional gap The evidence for conspecificity of 0. wagleri and show any indication of gene flow. Within the 0. poliocephala, being entirely based on a few range of wagleri, the more northerly Sonoran hybrids from an area in which perhaps neither population was separatedfrom that of southern speciesoccurs naturally, is not convincing in view Sinaloa and Nayarit (van Rossem 1934) as 0. of the striking differences between the popula- wagleri griseicepson the basis of being relatively tions. I suggestthat Ortalis wagleri be restored paler. Although that subspeciesis not generally to specific status. I further suggestthat the de- recognized(Friedmann et al. 1950, Vaurie 1965), scriptive English name Rufous-bellied Chacha- the fact that it was named suggeststhat if there laca rather than the patronymic Wagler’s Cha- is color variation in wagleri it is in the opposite chalaca (used for the combined speciesby AOU direction than would be expected if there were 1983) be applied to 0. wagleri and that West gene flow from poliocephala. Mexican Chachalacabe used for 0. poliocephala. Perhapspoliocephala has replacedwagleri, over a century or so, as the speciesof chachalacathat ACKNOWLEDGMENTS occurs around Puerto Vallarta. This would sug- I thank Allan R. Phillips for arrangingthe loan of spec- gest first, that wagleri occurred there originally, imens en route to deposit in the National Museum of and secondly, that poliocephalahas pushed it out Natural Sciences(Canada). and David Niles for the by extending its own range northward. There is loan of a specimen from’the Delaware Museum of Natural History. Peter R. Grant told me of specimens no evidence to support these suggestions.The he had taken in the area of concern,which were loaned earliest known specimen from Puerto Vallarta is by Richard J. Cannings of the Cowan Vertebrate Mu- a hybrid or intergrade, and there is no evidence seumofthe University of British Columbia. Specimens TAXONOMY OF RUFOUS-BELLIED CHACHALACA 753 from the American Museum of Natural History were MAYR, E., AND L. L. SHORT. 1970. Speciestaxa of borrowed throughthe courtesyof FrancoisVuilleumier North American birds. Publ. Nuttall Omithol. Club and Allison Andors. J. V. Remsen provided me with 9:1-127. information on the holdings of the Museum of Natural MCCLELLAN,M. E. 1927. Notes on birds of Sinaloa Science of Louisiana State University. M. Ralph and Nayarit, Mexico, in the fall of 1925. Proc. Browning provided technical support,and Claudia An- Calif. Acad. Sci., 4th ser., 16:1-51. gle prepared the figure. Browning, Ned K. Johnson, MOORE,R. T., AND D. R. MEDINA. 1957. The status and Henri Ouellet read and commented on the manu- of the chachalacasof western Mexico. Condor 59: script. 230-234. RIDGWAY,R., AND H. FRIEDMANN. 1946. The birds LITERATURE CITED of North and Middle America. U.S. Natl. Mus. Bull. 50( 10):l-484. AMERICAN ORNITHOLOGISTS ’ UNION. 1983. Check- SCHALDACH,W. J., JR. 1963. The avifauna ofcolima list of North American birds. 6th ed. American and adjacent Jalisco,Mexico. Proc. West. Found. Ornithologists’ Union, Washington, DC. Vert. Zool. l:l-100. AMERICANORNITHOLOGISTS UNION. 1985. Thirty- VAN ROSSEM,A. J. 1934. Critical notes on Middle fifth supplement to the American Ornithologists American birds. Bull. Mus. Comp. Zool. 77:387- Union check-list of North American birds. Auk 490. 102:680-686. VAURIE,C. 1965. Systematicnotes on the bird family DAMPS,L. I. 1965. Acoustic evidence of relationship Cracidae. No. 2. Relationships and geographical in Ortalis(Cracidae). Southwest. Nat. 10:288-30 1. variation of Ortalis vetula, Ortalis poliocephala, DELACOLJR,J., AND D. AMAWN. 1973. Curassows and Ortalis leucogastra.Am. Mus. Novit.-2222: and related birds. American Museum of Natural l-36. History, New York. VAURIE,C. 1968. Taxonomy of the Cracidae (Aves). FRIEDMANN.H.. L. GRISCOM.AND R. T. MOORE. 1950. Bull. Am. Mus. Nat. Hist. 138:133-259. Distributional check-list of the birds of Mexico. VUILLEUMIER,F. 1965. Relationships and evolution Part I. Pacific Coast Avifauna 29: l-202. within the Cracidae(Aves, Galliformes). Bull. Mus. GRISCOM,L. 1932. The distribution of bird-life in Comp. Zool. 134:l-27. Guatemala. Bull. Am. Mus. Nat. Hist. 64:1-439. WAGNER,H. 0. 1953. Die Hockohtihner der Sierra GRISCOM,L. 1934. The ornithology of Guerrero, Madre de Chiapas/Mexiko. VerBff. Mus. Bremen, Mexico. Bull. Mus. Como. Zool. 75367-422. Reihe A, 2:105-128. HELLMAYR,C. E., ANDB. COGOVER.1942. Catalogue ZIMMERMAN,D. A., AND G. B. HARRY. 1951. Sum- of birds of the Americas. Part 1, no. 1. Zool. Ser., mer birds of Autlan, Jalisco.Wilson Bull. 63:302- Field Mus. Nat. Hist. 13. 314. LEOPOLD,A. S. 1959. Wildlife of Mexico. Univ. of California Press, Berkeley.