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tion of artificial nests. .I. Wildl. Manage. 58:249- OLSON, S. L. 1981. Natural history of vertebrates on 254. the Brazilian islands of the mid south Atlantic. FLACK, .I. A. D. AND B. D. LLOYD. 1976. The effect of Nat. Geog. Sot. Res. Rep. 13:481-492. rodents on the breeding success of the South Is- PATERSON,A. 1972. Birds of the Bahamas. Durell Pub- land Robin. Pp. 59-66 in The ecology and control lications, Kennebunkport, Maine. of rodents in New Zealand nature reserves (P R. PATON, I? W. C. 1994. The effect of edge on avian nest Dingwall, I. A. E. Atkinson, and C. Hay, Eds.). success: how strong is the evidence? Conserv. Departments of Land and Survey, Wellington, Biol. 8: 17-26. New Zealand. PICMAN, J. 1988. Experimental study of predation on GIBBS, J. P 1991. Avian nest predation in tropical wet eggs of ground-nesting birds: effects of habitat forest: an experimental study. Oikos 60: 155-16 1. and nest distribution. Condor 90: 124-l 3 1. GNAM, R. S. 1991. Natural history of the Bahama Par- REARDON, J. D. 1951. Identification of waterfowl nest rot Amazona leucocephala bahamensis on Abaco predators. J. Wildl. Manage. 15:386-395. Island. Proc. Symp. Nat. Hist. Bahamas 4:67-74. ROCKWELL, R. H. 1932. Southward through the dol- HARTLEY, M. J. AND M. L. HUNTER, JR. 1998. A meta- drums. Nat. Hist. 32:424-436. analysis of forest cover, edge effects, and artificial STAUS, N. L. AND E H. BARNWELL. 1996. The tropical nest predation rates. Conserv. Biol. 12:465-469. Atlantic land crab Cardisoma guanhumi feeds on HASKELL, D. G. 1995. A reevaluation of the effects of bird eggs. Am. Zool. 36:8OA. forest fragmentation on rates of bird-nest preda- THOMAS, B. G., E. P WIGGERS, AND R. L. CLAWSON. tion. Conserv. Biol. 5:1316-1318. 1996. Habitat selection and breeding status of HOSMER, D. W. AND S. LEMESHOW. 1989. Applied lo- Swainsons’ Warblers in southern Missouri. J. gistic regression. John Wiley and Sons, New York. Wildl. Manage. 60:611-616. LATTA, S. C., J. M. WUNDERLE, JR., E. TERRANOVA, TREVOR, J. T, R. W. SEABLOOM,AND R. D. SAYLER. AND M. PAGAN. 1995. An experimental study of 199 1. Identification of mammalian predators at ar- nest predation in a subtropical wet forest follow- tificial waterfowl nests. Prairie Nat. 23:93-99. ing hurricane disturbance. Wilson Bull. 107:590- VANDER HAEGEN, W. M. AND R. M. DEGRAAF. 1996. 602. Predation on artificial nests in forested riparian LAURANCE, W. E, J. GARESCHE, AND C. W. PAYNE. buffer strips. J. Wildl. Manage. 60:542-550. 1993. Avian nest predation in modified and nat- WATT, B. D. AND D. S. BRADSHAW. 1995. Ghost crab ural habitats in tropical Queensland: an experi- preys on Piping Plover eggs. Wilson Bull. 107: mental study. Wildl. Res. 20:7 1 l-723. 767-768. MAJOR, R. E. AND C. E. KENDAL. 1996. The contri- WOLCOTT, T G. 1988. Ecology. Pp. 55-96 in Biology bution of artificial nest experiments to understand- of the land crabs (W. W. Burggren and B. R. Mc- ing avian reproductive success: a review of meth- Mahon, Eds.). Cambridge Univ. Press, Cam- ods and conclusions. Ibis 138:298-307. bridge, U.K.

Wilson Bull., 11 l(4), 1999, pp. 564-569

Notes About the Distribution of Pauxi pauxi and Aburria aburri in

Jo& L. Silval%*

ABSTRACT.-In this paper I review the current principally with 18 national parks located from the distribution of the Northern Helmeted Curassow northern coastal mountains of central Venezuela to the (Pauxi pauxi) and the Wattled Guan (Aburria aburri) Andes Cordillera and Sierra de Perija. Pa& pauxi was in Venezuela. The historical range of P. paxci was re- recorded only in three localities outside national parks duced as a result of human population growth and hab- and may have expanded from its historical distribution itat perturbations. The current distribution corresponds in the eastern part of the country. Aburria aburri was recorded in Sierra de Perijd and western MCrida to ’ ’ NYZS The Wildlife Conservation Society, 185th southern Tachira, including four new localities; three & Southern Blvd., Bronx, New York 10460-1099. in national parks. Both species are endangered in Ven- * Current address: Univ. of Florida, Wildlife Ecolo- ezuela and their survival will depend on environmental gy and Conservation Dept., PO. Box 110430, 303 education programs and enforcement of the law. Re- Newins-Ziegler Hall, Gainesville, FL 3261 l-0430; ceived 9 Feb. 1998, accepted 20 July 1999. E-mail: [email protected] SHORT COMMUNICATIONS 565

The Wildlife Conservation Society of the Luis, Cueva Quebrada de1 Toro, and Tirgua New York Zoological Society funded a study National Parks. Although it was reported in on human impacts on game species in pro- (Collar et al. 1992, tected areas of Venezuela from 1985 to 1990 Wege and Long 1993) according to the rang- (Silva and Strahl 1991, 1994, 1996, 1997). ers, it was no longer present in the park in During 1985-1996, censuses and interviews 1996. were conducted and new data about the dis- Pauxi pauxi is rare in national parks and tribution of Pauxi pauxi (Northern Helmeted almost extinct outside national parks because Curassow) and Aburria aburri (Wattled Guan) hunting pressure is highest outside the parks were collected. My objective in this paper is (Silva and Strahl 1991, 1996, 1997). The few to present these data and review the status of locations where P. pauxi was found outside P. pauxi and A. aburri in Venezuela. national parks included the Sanchdn River In Venezuela Pauxi pauxi ranges from the Hydraulic Reserve (10” 24 ’ N, 68” 09 ’ W), the northern coastal mountains of central Vene- River Protectoral High Basin (10” 24 ’ zuela to the Andes Cordillera and Sierra de N, 68” 15 ’ W) and Finca El Jaguar (10” 26 ’ Perija in rain forest and cloud forest. Most au- N, 68” 59 ’ W). thors (Wetmore and Phelps 1943; Phelps and From interviews with hunters I found that Phelps 1958, 1962; Delacour and Amadon P. pauxi probably existed or may still live in 1973; Meyer de Schauensee and Phelps 1978; eastern Venezuela. A hunter in Teresen (Mon- Collar et al. 1992; Rodriguez and Rojas-Suar- agas State) narrated the size, color pattern, and ez 1995) cited the states and localities of the helmeted color of this species, and imitated its historical range as follows: P. p. pauxi: south- booming song. He recognized the bird from a ern Miranda state in Cerro Negro (Guatopo set of cracid pictures. Pauxi pauxi was seen National Park); north in El Calvario; in La Hormiga (9“ 54 ’ N, 62” 58 ’ W), Cane Distrito Federal; coastal mountains in Aragua Payanuco, Guarapiche Forest Reserve (Sucre state (Henri Pittier National Park); Carabobo and Monagas States) between 1968 and 1973. state in Valencia, San Esteban, and Montal- Because only 1 of 25 interviewed hunters in ban; east Falcon to state in Tucacas, TeresCn saw a P. pauxi, and saw it only once, Nirgua, mountains inland from Aroa, and La- this should not be interpreted as range exten- gunita de Aroa; state in Cubiro, and Ya- sion. The nearest locality of the historical dis- cambd National Park; from northern M&da tribution (Guatopo National Park) is approxi- to southern Tachira state in Montana de Li- mately 405 km from Guarapiche Forest Re- mones, La Azulita, and Burgua. Pauxi p. gil- serve, and this separation is settled with towns liardi: Zulia state from southern Sierra de Per- and cities. More likely the former distribution ija (Sierra de 10s Motilones) to southern Rio record was incomplete. Pauxi pauxi is very Tucuco, in Fila Macoita, Campamento Avispa, likely to be extinct in Guarapiche because of Cerro Yin-taina, upper Rio Negro, and La Sa- high hunting pressure. bana. A continuous distribution in the histor- An interesting characteristic of P. pauxi is ical range was assumed (Fig. 1A) because of the brown phenotype that sometimes occurs historical records, and Central Cordillera and in females. Males and females are typically Los Andes Cordillera were almost a continu- black with a white belly. Hunters call the ous forest in the past. brown morph “Canaguey” or “Pauji Amaril- The habitat available for P. pauxi has been lo.” It was reported in the Sierra de Perija, greatly reduced as a result of deforestation, where two specimens were collected between fragmentation, and habitat alteration. Almost 1941 and 1957 (Delacour and Amadon 1973). all the remnant forest available in northern Here I report 26 new localities of the brown Venezuela was decreed as national parks by morph seen between 1949 and 1993 (Table 1). the Venezuelan government. Consequently, Of the 34 birds sighted, a single brown phe- these national parks are isolated. I found that notype was seen with one black phenotype at the current distribution of P. pauxi mainly co- Fila Real (1975) one with two black pheno- incided with the distribution of national parks types at Casa de Tejas (1980), and one with situated in its historical range (Fig. lB), as seven black phenotypes at El Corazon (1988). well as new localities such as Sierra de San Two brown phenotypes were seen with two 566 THE WILSON BULLETIN l Vol. III, No. 4, December 1999

A I I 700 64O

B I I 70” 640

FIG. 1. A. Historical range of Pauxi paui according to Delacour and Amadon (1973), Meyer de Schauensee and Phelps (1978), Collar and coworkers (1992) and Rodriguez and Rojas-Suarez (1995). B. Current range of fat.& pauxi in Venezuela. Boundaries of national parks are shown, but the species may not be distributed through the entire park. Numbers are national parks, Roman numerals are other localities, and letters are states with the exception of Caracas (Ca), the capital of Venezuela. Code: 1 = Guatopo (122,464 ha). 2 = El Avila (81,800 ha). 3 = Macarao (15,000 ha). 4 = Henri Pittier (107,800 ha). 5 = San Esteban (43,500 ha). 6 = Morrocoy (32,090 ha). 7 = Sierra de San Luis (20,000 ha). 8 = Cueva Quebrada de1 Toro (4,885 ha). 9 = Yurubi (23,670 ha). 10 = Tirgua. 11 = Terepaima (18,650 ha). 12 = Yacambu (14,580 ha). 13 = Dinira (42,000 ha). 14 = Guaramacal (21,000 ha). 15 = Sierra de La Culata (200,400 ha). 16 = Sierra Nevada (276,446 ha). 17 = Tap+Caparo. 18 = El Tama (109,000 ha). 19 = Sierra de Perija (295,288 ha). I = Sanchdn River Hidraulic Reserve (8,100 ha). II = Cojedes River Protectoral High Basin (276,000 ha). III = Finca El Jaguar (16,000 ha). IV = Guarapiche Forest Reserve (576,500 ha). MO = Monagas. S = Sucre. G = Guarico. Mi = Miranda. Ca = Caracas. A = Aragua. C = Carabobo. Y = Yaracuy. F = Falc6n. L = Lara. Tr = Trujillo. Me = Merida. T = Tachira. Z = Zulia. SHORT COMMUNICATIONS 567

TABLE 1. Brown phenotype of Pauxi pnuxi recorded in Venezuela.

Locality Date LOCatKIn Coordinates n

Hem-i Pittier 1975 La Glorieta 10” 28’N 67” 45’W Hemi Pittier 03/1984 La Regresiva 10” 22’N 67” 44’W Henri Pittier 1993 El Saltico _B Henri Pittier 1993 Los Riitos San Esteban 1955 Burro Sin Cabezas San Esteban 1960 Burro Sin Cabezas San Esteban 198687 Flor Amarillo San Esteban 1987 Flor Amarillo San Esteban 07/1989 El Tanque San Esteban 1991 San Felipe San Esteban El Dique 10” 18’N 67” 59’W San Esteban La Panta (Qda. Yaguas) San Esteban Ranchitos San Esteban La Manguera Terepaima 1949 Los Portones 9” 52’N 69” 2O’W Terepaima 1975 Fila Real 9” 55’N 69” 16’W Terepaima 0411992 Fila Real 9” 53’N 69” 17’W Yacambu 1979 El Blanquito, Qda. La Toma 9” 42’N 69” 34’W Yacambu 1983 Barro Amarillo Yacambu 1988 El Corazon Yacambu 1988 La Canada Yacambu 06/1992 El Blanquito 9” 42’N 69” 34’W Yacambti La Escalera 9” 42’N 69” 3O’W Yacambu La Postora 9” 41’N 69” 37’W Yacambu El Blanquito 9” 42’N 69” 34’W Yacambd Cerro Blanco 9” 37’N 69” 3O’W Sierra Nevada Alto de la Aguada 8” 37’N 70” 4O’W Sierra Nevada San Benito 8” 40’N 70” 37’W Rio Sanchon 1980 La Cumbre de1 Cache Rio Sanchon 1 l/1980 Casa de Tejas

a Nameof localities do not appear on maps because they are local names used by hunters and the exact locations are unknown

black phenotypes at El Saltico and Los Riitos ed A. aburri since they were young. Perhaps, in 1993. the historical range was continuous. Although Aburria aburri was mainly recorded in the Rodriguez and Rojas-Suarez (1995) stated that western part of Venezuela (Fig. 2). The his- A. aburri probably was found in the eastern torical range was reported to be in the Sierra part of Costa Cordillera, they did not mention de Perija and west MCrida to southern Tachira the source of their information. in rain and cloud forest (Delacour and Ama- The present status of P. pauxi and A. aburri don 1973, Meyer de Schauensee and Phelps is worrisome. According to the population 1978, Rodriguez and Rojas-Suarez 1995). The censuses (Silva and Strahl 1991, 1997) and current distribution of A. aburri indicates that the interviews (Silva and Strahl 1996), P. the record of the historical range may have pauxi and A. aburri have very low densities been incomplete. Aburria aburri was recorded with A. aburri being more rare than P. pauxi. in Sierra Nevada National Park (54 inter- Both species were considered Endangered by viewed hunters), in Terepaima National Park the Cracid Specialist Group (Strahl et al. (observed), and in Yacambd National Park 1994) and by researchers of a recent study in and the basin of Yacambu River (S. Boher, Venezuela (Rodriguez and Rojas-Suarez pers. comm., and 338 interviewed hunters). 1995). Habitat destruction and illegal hunting These were new distribution records, but they are the principal causes of the decline in pop- did not suggest an extension of the historical ulation of both species, and their conservation range because hunters over 60 years old hunt- will rely on hunter education (Silva and Pel- 568 THE WILSON BULLETIN * Vol I I I, No. 4, December 1999

(A) (B) FIG. 2. Historical (A) and current distribution (B) of Aburria aburri in Venezuela. Abbreviations are the same as Fig. 1

legrini 1996, Silva 1997) and enforcement of subspecies of birds from Venezuela, the rufous the law. phase of Pauxi pauxi and other notes. Proc. Biol. Sot. Wash. 7511999204. ACKNOWLEDGMENTS RODRIGUEZ, J. P AND E ROJAS-SUAREZ. 1995. Libro Rojo de la Fauna Venezolana. ExLibris, Caracas, NYZS The Wildlife Conservation Society funded Venezuela. the main projects. I thank hunters who collaborated SILVA, J. L. 1997. Proyecto de Education para la Con- with the interviews. A. Grigss reviewed the manu- servacion de la Familia Cracidae en 10s Parques script. Nacionales al Norte de Venezuela. Pp. 424-436 in The Cracidae: their biology and conservation LITERATURE CITED (S. Strahl, S. Beaujon, D. M. Brooks, A. J. Be- COLLAR, N. J., L. l? GONZAGA, N. KRABBE, A. MAD- gaze, G. Sedaghatkish, and E Olmos, Eds.). Han- ROAO NIETO, L. G. NARANJO, T A. PARKER, III, cock House, Hong Kong, China. AND D. C. WEGE. 1992. Threatened birds of the SILVA, J. L. AND N. PELLEGRINI.1996. Proyecto de Ed- Americas: the ICBP/IUCN red data book 2. Inter- ucacion para Cazadores Furtivos en Parques Na- national Council for Bird Preservation, Cam- cionales. Natura 106:59-62. bridge, U.K. SILVA, J. L. AND S. STRAHL. 1991. Human impact on DELACOUR, J. AND D. AMADON. 1973. Curassows and populations of guan, curassow and chachalacas in related birds. American Museum of Natural His- Venezuela. Pp. 36-52 in Neotropical wildlife use tory, New York. and conservation (J. G. Robinson and K. H. Red- MEYER DE SCHAUENSEE,R. AND W. H. PHELPS, JR. ford, Eds.). Chicago Univ. Press, Chicago, Illinois. 1978. A guide to the birds of Venezuela. Princeton SILVA, J. L. AND S. STRAHL. 1994. Usos Folcloricos de Univ. Press, Princeton, New Jersey. la Fauna Silvestre en Nueve Parques Nacionales PHELPS,W. H. AND W. H. PHELPS,JR. 1958. Lista de al Norte de Venezuela. Vida Silvestre Neotropical Aves de Venezuela con su distribucidn I: no pas- 3:100-107. seriformes. Bol. Sot. Venezolana Cienc. Nat. 19: SILVA, J. L. AND S. STRAHL. 1996. La Caza Furtiva en 1-317. 10s Parques Nacionales al Norte de Venezuela. PHELPS,W. H. AND W. H. PHELPS,JR. 1962. Two new Vida Silvestre Neotropical 5: 126139. SHORT COMMUNICATIONS 569

SILVA, J. L. AND S. STRAHL. 1997. Presi6n de Caza for Neotropical guans, curassows, and chachala- sobre Poblaciones de Cricidos en 10s Parques Na- cas. IUCN/SSC Conservation Breeding Specialist cionales al Norte de Venezuela. Pp. 437-448 in Group, Apple Valley, Minnesota. The Cracidae: their biology and conservation (S. WEGE, D. C. AND A. LONG. 1993. Bird conservation Strahl, S. Beaujon, D. M. Brooks, A. J. Begazo, priorities: country profile, Venezuela. BirdLife G. Sedaghatkish, and E Olmos, Eds.). Hancock Conserv. Series 3:1-85. House, Hong Kong, China. WETMORE, A. AND W. H. PHELPS.1943. Description of STRAHL, S., S. ELLIS, 0. BYERS, AND C. PLASSE. 1994. a third form of curassow of the Genus Pauxi. J. Conservation assessment and management plan Washington Acad. Sci. 33:142-146.

Wilson Bull., 11 l(4), 1999, pp. 569-571

Western Burrowing Owls in California Produce Second Broods of Chicks

Jennifer A. GervaisQ and Daniel K. Rosenberg ’

ABSTRACT-We present the first evidence that rameters such as survival and reproductive western Burrowing Owls are capable of raising a sec- rates. These can be used in simplified models ond brood of chicks within a nesting season once their that allow the examination of the effects of first brood successfully fledges. Two pairs of owls in central California known to have successfully fledged possible management actions or environmen- chicks from a first brood renested in 1998, with one tal perturbations on population persistence. pair producing five additional fledglings. Received 29 Such an approach has recently been used for March 1999, accepted 15 July 1999. the northern Spotted Owl (Strix occidentalis; Noon and Biles 1990), and for predicting the effects of pesticide exposure on wildlife pop- Western Burrowing Owls (Athene cunicu- ulations (Caswell 1996, Calow et al. 1997). laria) are thought to be declining throughout Simulations of generalized life history strat- much of their range (DeSante et al. 1997, egies have shown that for a species with rel- James and Espie 1997). The potential causes atively low adult survivorship and a short life of these declines vary with location, but likely span, reproductive success may be most influ- include large-scale habitat destruction from ential in maintaining population viability (Em- farming or development, reductions in species len and P&itch 1989). This is likely to be gen- such as ground squirrels that create the bur- erally true for Burrowing Owls. They are ca- rows that the owls use, and agricultural chem- pable of producing up to 12 eggs in a clutch icals (James and Espie 1997, Gervais et al. in (Haug et al. 1993), and we have observed up press). Because of the perceived threat to the to 10 young fledged per nest in good repro- viability of Burrowing Owl populations, the ductive years. In addition, Burrowing Owl an- species has been listed as endangered, threat- nual adult survivorship appears to be quite ened, or of special management concern in a low, with between-year return rates ranging number of North American states and prov- from 33-58% (Haug et al. 1993), and a lon- inces (Haug et al. 1993). gevity record for a wild banded owl of 8 years Effective conservation at the species level and 8 months (Kennard 1975). If sensitivity requires understanding the population dynam- analyses prove that the Burrowing Owl fits the ics of the species in question, which in turn predictions of the Emlen-P&itch model (Em- means accurate estimation of demographic pa- len and P&itch 1989) for a small, relatively short-lived species, then accurate assessment of reproductive potential of Burrowing Owls ’ ’ Oregon Cooperative Fish & Wildlife Research is essential to evaluating population processes. Unit, Dept. of Fisheries and Wildlife, Oregon State Univ., Corvallis, OR 9733 1. Only Florida Burrowing Owls have been 2Corresponding author; E-mail: known to produce second broods within a sea- [email protected] son (Millsap and Bear 1990). We report two