ORNITOLOGIA NEOTROPICAL 14: 247–262, 2003© The Neotropical Ornithological Society

AVIFAUNA OF THE NORTHERN PARAGUAYAN CHACO

Kristof Zyskowski1,4, Mark B. Robbins1, A. Townsend Peterson1, Kimberly S. Bostwick1, Robert P. Clay2, & Luis A. Amarilla3

1University of Kansas Natural History Museum, Lawrence, Kansas 66045, USA.2Guyra Paraguay: Conservación de Aves, C.C. 1132, Asunción, Paraguay.

3Museo Nacional de Historia Natural del Paraguay, San Lorenzo, Paraguay.

Resumen. – Avifauna chaqueña del norte de Paraguay. – Inventarios llevaros a acabo en cinco sitiosen el chaco del norte de Paraguay indicaron la presencia de 233 especies de aves, incluyendo a MosquetaBoreal (Empidonax alnorum), la cual se registra por primera vez en el país. Se documentaron por primera veztres especies por medio de especimenes [Chiripepé de Cabeza Gris (yrrhura molinae), Pijuí Ocráceo (Poe-cilurus scutatus) y Batará Boliviano (Thamnophilus sticturus)] y una por grabaciones de cantos [Piojito Trinador³Serpophaga griseiceps)]. Se registraron dos especies nuevas para el chaco de Paraguay, y 22 especies nuevaspara las zonas del Alto Chaco o Matogrosense (sensu Hayes 1995). Comparaciones preliminares entresitios, junto con información adicional publicada, apoyan a la idea de que el recambio de especies de sitio asitio es considerable en el bioma del chaco. La recien declarada Reserva de Biosfera del Chaco, si se imple-menta y se protege efectivamente, representa un paso importante hacía la conservación de la avifauna delnorte del chaco.

Abstract. – Surveys at five sites in the chaco biome in northern Paraguay revealed the presence of 233 birdspecies including one species, Alder Flycatcher (Empidonax alnorum) new for the country. Four species weredocumented for the first time with specimens [Green-cheeked Parakeet (Pyrrhura molinae), Ochre-cheekedSpinetail (Poecilurus scutatus), and Bolivian Slaty-Antshrike (Thamnophilus sticturus)] or tape-recordings [Gray-crowned Tyrannulet (Serpophaga griseiceps)]. Two additional species were new for the Paraguayan chaco and22 species for the regions of Alto Chaco or Matogrosense (sensu Hayes 1995). Preliminary comparisonsamong sites, along with other published information, support the idea that site-to-site turnover of speciesis high in the chaco biome. The recently declared Reserva de Biosfera del Chaco, if effectively imple-mented and protected, will represent an important step towards the conservation of the northern chacoavifauna. Accepted 3 October 2002.

Key words: Paraguay, chaco, Neotropical, faunal turnover, austral migration, conservation.

INTRODUCTION areas still holding primary vegetation (Peter-

Effective biodiversity conservation dependscritically on quality data regarding the geo-graphic distributions of species in remote______________4Current address: Peabody Museum of Natural His-tory, Yale University, P.O. Box 208118, NewHaven, Connecticut 06520, USA. E-mail: kris-tof.zyskowski@yale.edu

son et al. 1993). Paraguay holds an importantportion – almost 25% – of the South Ameri-can dry-forest biome called the chaco, repre-senting 61% of the national territory(Madroño 1995, Vera et al. 2000). As Short(1975) underscored in his treatise on thechaco avifauna, northern Paraguay and south-eastern Bolivia hold the last “extensive uncutstands” of dry woodland in the region. Given

247

ZYSKOWSKI ET AL.

broad patterns of species turnover across thechaco (Short 1975, Kratter et al. 1993), andgiven that the chaco of northern Paraguay hasnever seen detailed ornithological survey, newinventories become important for establish-ing optimal strategies for conservation in theregion. Indeed, the only detailed single-sitesurveys of the Paraguayan chaco are those ofShort (1976) at Lichtenau, depto. PresidenteHayes, and Brooks (1997) at Estancia Toledo,depto. Boqueron, both of which lie c. 250 kmsouth of our southernmost site.

In 1975, Paraguay decreed the 7800 km²Parque Nacional Defensores del Chaco (Fig.1), one of the first protected areas to be estab-lished in the country. An initiative to extend

the area protected as far as the Bolivian bor-der recently came to fruition with presidentialdecree 13202 of 21 May 2001, that boldlydeclared the entire northern Paraguayanchaco (a total of 47,072.5 km², or 10% of thenational territory) as the “Reserva de Biosferadel Chaco.” This nationally recognized bio-sphere reserve includes three existing pro-tected areas (Parque Nacional Defensores delChaco, Parque Nacional Teniente AgripinoEnciso, and the now expanded MonumentoNatural Cerro Chovoreca) and incorporatesthree new reserves within the national systemof protected areas (Parque Nacional RíoNegro, Reserva Natural Cerro Cabrera-Timané, and Parque Nacional Médanos del

FIG. 1. Map of Paraguay, showing the location of the five study areas and other important features men-tioned in the text. Shading denotes the approximate extent of Paraguayan chaco.

248

AVIFAUNA OF PARAGUAYAN CHACO

Chaco). This massive area of well-preservedhabitat has seen no published avifaunal list,with the exception of that included within therapid ecological assessment of Defensores delChaco (DPNVS 1999). The present studythus seeks to provide preliminary avifaunalsurveys for five sites in extreme northern Par-aguay—two within the Parque Nacional LosDefensores del Chaco, and three near theBolivian border (Fig. 1). Our inventory workat the latter three sites represents the first avi-faunal surveys from within the MonumentoNatural Cerro Chovoreca and the newly cre-ated Parque Nacional Río Negro.

STUDY AREAS AND METHODS

Study areasParque Nacional Defensores del Chaco. Two siteswithin the Parque Nacional Los Defensoresdel Chaco, depto. Alto Paraguay, were sur-veyed in late October 1995 by Robbins,Zyskowski, Rosalía Fariña, and Sergio Villan-ueva. The first, Cerro León (20°26’S,60°19’W), was surveyed from the evening of21 October through the morning of 25 Octo-ber. The second site, Madrejón (20°40’S,59°50’W; c. 54 road km E of Cerro León),was surveyed from the afternoon of 25October through the early morning of 31October 1995, and briefly (c. 5 h) byZyskowski, Bostwick, and Peterson on 17September and 10 October 1999.

Conditions at Cerro León were extremelywindy, hot, and dry. Strong winds, fromthe northeast and east, persisted day andnight for virtually our entire stay at CerroLeón. Temperatures peaked at 42° C bymid-afternoon and remained at 40° C untilafter sunset. Surface water was limited to twoshallow (one a few cm deep, the other about30 cm deep) pools. Most trees and busheswere either devoid of leaves, or still in the pro-cess of losing them. The above conditions,combined with very limited shade (cloudless

every day) and limited mobility (all areasaccessed on foot), restricted the number ofmist-nets at this site (8), which were con-stantly filled with dry leaves by the strongwinds. Censuses were conducted up to c. 7km north and c. 5 km south of our road-basedcamp.

At Madrejón, climatic conditions were thesame as at Cerro León until a strong coldfront arrived from the west at 19:00 (GMT-4h) on 27 October 1995. By the morning of 28October, the temperature had dropped to 17°C with a completely overcast sky. At 15:30,rain began and continued until c. 09:30 thenext morning. By 17:00 on the 29 October,the wind had ceased and the sky had clearedcompletely. The sky was overcast on 30 Octo-ber. Censuses were limited to 3–4 road kmnorth, west, and south of park headquarters.

Cerro Chovoreca. The study site was chosen soas to be situated as far north as possible in thedry forests of the Paraguayan chaco. The ini-tial goal was to arrive at the Bolivian border(Cerro Chovoreca, Hito VII; Fig. 1). How-ever, access from the direction originallyplanned (via Base Aérea Adrián Jara, or Base5) proved impossible, and the main accessroute (Picada Chovoreca) was both impass-able and surrounded by naturally disturbedhabitat (perhaps an old burn) within a fewkilometers north of Linea 3. For these rea-sons, activities were focused along PicadaChovoreca immediately south of Linea 3 (cen-ter 19°35’S, 59°16’W) in an area of about 10km2. Sampling was carried out during 19–24September 1999 by Zyskowski, Peterson,Bostwick, and Amarilla.

The study site included two principal hab-itat types: relatively tall dry forest and scrubbywoodland. The forest was 10–15 m tall, with afairly uniform canopy. At the time of ourfieldwork, just prior to the normal onset ofrains and following four months of drought,only about 5% of trees had leaves. The

249

ZYSKOWSKI ET AL.

scrubby woodland averaged 1–3 m tall, withoccasional tall trees and palms. There, essen-tially none of the vegetation had leaves. Thishabitat appeared to be the result of a combi-nation of topographic effects (low-lying ter-rain) and disturbance, perhaps a major forestfire. We found no surface water, which led toserious problems with moisture-seeking hon-eybees (Apis sp.). Both habitats were sampled,although efforts focused more on the forest(about 70% of effort) than on woodland(30%).

Estancia 42. During 5–12 September 1997,Clay, Ian Burfield, Dave Capper, RosalíaFariña, Corinne Kennedy, Mirna Perrens andRob Pople conducted ornithological surveysat Estancia 42, 35 km northwest of PuertoBahía Negra (20°03’S, 58°10’W). The estanciaand surrounding areas were originally coveredwith semihumid, medium-height forest (10–20 m), but we observed few areas of the prop-erty with closed canopy forest of heightgreater than 10–15 m. Surveys, includingmist-netting, were conducted along the last 5km of the principal access track, and alongthe network of surrounding trails. In additionto forest, the survey area included a smallfreshwater marsh, patches of regeneratingscrub and implanted pasture, and small bod-ies of standing water alongside the accesstrack. Munitions cartridges and varioushearths with the remains of brocket deer(Mazama sp.), peccary (Tayassu sp.), and tegulizards (Tupinambis sp.) suggested that consid-erable hunting occurred in the area, perhapsexplaining the notable absence of ChacoChachalaca (Ortalis canicollis) and the overallscarcity of large mammals. Details of some ofthe highlights of the ornithological surveys atthis property have been presented elsewhere(Clay et al. 1998; Capper et al. 2001a, 2001b).

Estancia Triunfo. During 5–9 October 1999,Zyskowski and Bostwick sampled a block of

dry forest at Estancia Triunfo, c. 14 road kmW of Bahia Negra (20°06’S, 58°16’W). Thisprivately-owned ranch included a small patch(c. 12 x 7 km) of relatively undisturbed dryforest adjacent to the more degraded scruband pastures. Censuses and mist-netting wereconducted along a 7 km long narrow huntingtrail that traversed the patch, and along thelast 5 km of the access road. The forest wasabout 15 m tall and carpeted with terrestrialbromeliads (Bromelia serra). The only standingwater in the area was two artificial, 10 mdiameter ponds along the main road. Despiteformer hunting, the forest was still inhabitedby numerous tinamous (Crypturellus, two spe-cies), Chaco Chachalacas, and two species ofmonkeys (Aotus azarae and Callicebus donacophi-lus); we also observed a single Giant Anteater(Myrmecophaga tridactyla).

MethodsSampling. Work was oriented towards a prelim-inary inventory of the birds at each site. Threeprincipal approaches were employed: mist-netting (c. 65 net-h at Cerro León, 612 in theChovoreca forest, c. 200 at Estancia 42, and c.80 at Estancia Triunfo), visual observations(c. 95 h of observation by teams of 1–3 expe-rienced observers at Chovoreca, 130 h atEstancia 42), and sound recordings. To docu-ment identifications, as well as to permit morein-depth studies at a later date, scientific spec-imens of most of the species were collectedusing mist-nets and shotguns, and are depos-ited at the Museo Nacional de Historia Natu-ral del Paraguay, and at the University ofKansas Natural History Museum. Soundrecordings are deposited at the MacaulayLibrary of Natural Sounds, Cornell Labora-tory of Ornithology, Ithaca, New York (KZand MBR), and National Sound Archive,Wildlife Section, London (RPC). Taxonomyand nomenclature follow Hayes (1995), asamended by AOU (1998) and other recentpublications where appropriate.

250

AVIFAUNA OF PARAGUAYAN CHACO

RESULTS

Species diversity. Some 235 species wererecorded at the five study sites: 117 at CerroLeón, 135 at Madrejón, 101 at Chovoreca, 92at Estancia Triunfo, and 160 at Estancia 42.Species accumulation curves for Chovorecaindicated that the inventory was approachingcompletion, likely better than 90% complete(Peterson & Slade 1998); however, it must beemphasized that this statistic refers to thosespecies “present” and “detectable”2 at thetime of the inventory.

Alder Flycatcher (Empidonax alnorum) wasrecorded for the first time in Paraguay, andthree additional species: Green-cheeked Para-keet (Pyrrhura molinae), Ochre-cheeked Spine-tail (Poecilurus scutatus), and Bolivian Slaty-Antshrike (Thamnophilus sticturus) had not beendocumented previously with specimens.Details of the first records of the BolivianSlaty-Antshrike, a species essentially endemicto the dry forests of Bolivia and Paraguay(Isler et al. 1997), are reported elsewhere(Clay et al. 1998, Capper et al. 2001a). Voicerecordings of Gray-crowned Tyrannulet (Ser-pophaga griseiceps) from Estancia 42 appear torepresent the first documentation of this spe-cies’ presence in Paraguay (see Speciesaccounts).

The presence of Barred Forest-Falcon(Micrastur ruficollis) and Pheasant Cuckoo (Dro-mococcyx phasianellus) in the Paraguayan chacowas documented for the first time, while 22species were recorded for the first time in theAlto Chaco or Matogrosense regions (asdefined by Hayes 1995). Species recorded forthe first time in the Alto Chaco region were:Yellow-collared Macaw (Primolius auricollis),Yellow-chevroned Parakeet (Brotogeris chiriri),Rufous Nightjar (Caprimulgus rufus), Little(Veniliornis passerinus) and Pale-crested (Celeuslugubris) woodpeckers, White-lored Spinetail(Synallaxis albilora), Streaked Xenops (Xenopsrutilans), Fawn-breasted Wren (Thryothorus

guarayanus), Chestnut-vented Conebill (Coniros-trum speciosum), Green-winged Saltator (Saltatorsimilis), and Saffron-billed Sparrow (Arremonflavirostris). The following species wererecorded for the first time in the Mato-grosense region, details of which, with theexception of White-naped Xenopsaris (Xenop-saris albinucha, see Species accounts), werepublished by Capper et al. (2000a, 2000b):Tataupa Tinamou (Crypturellus tataupa),Plumbeous (Ictinia plumbea) and Swallow-tailed(Elanoides forficatus) kites, Pavonine Cuckoo(Dromococcyx pavoninus), Spectacled Owl (Pulsa-trix perspicillata), Rufous Nightjar, LineatedWoodpecker (Dryocopus lineatus), Small-billedElaenia (Elaenia parvirostris), White-napedXenopsaris, Orange-headed Tanager (Thly-popsis sordida), and Dull-colored Grassquit(Tiaris obscura).

Breeding condition. Almost no breeding behaviorwas observed at Cerro León and Madrejón[see Plain Inezia (Inezia inornata) speciesaccount for an exception] until rains arrivedon 28 October. Immediately after the frontpassed, however, columbids and virtuallyevery passerine began courtship behavior,with persistent singing and territorial defense.As a result of the dramatic increase in vocal-izations, our perception of species numbersand composition literally changed overnight,with eight species recorded for the first timethe following morning.

Unfortunately, because of prior transpor-tation arrangements, we were unable toremain to fully document post-rain changesin the avifauna’s breeding status. Gonadaldata from specimens deposited at the Univer-sity of Kansas Natural History Museumdocument that some individuals of at least 13of 45 species were already experiencingdramatic physiological changes prior to the28 October rains; gonadal enlargementmay have commenced as a result of heavyrains that passed through the Filadelfia/

251

ZYSKOWSKI ET AL.

Defensores region on 19–20 October. Ten of33 species collected at Cerro Chovorecashowed some signs of enlarged gonads, inspite of the 6+ months of zero rainfall thatpreceded our visit.

Ant-following birds. We observed two ant-swarms during the surveys. On 6 September1997 the following species were associatedwith an antswarm at Estancia 42: 1 Gray-necked Wood-Rail (Aramides cajanea), 1 Pale-crested Woodpecker, 3 Black-banded Wood-creepers (Dendrocolaptes picumnus), 2 BolivianSlaty-Antshrikes, 3 White-backed Fire-eyes(Pyriglena leuconota), 5 Purplish Jays (Cyanocoraxcyanomelas), 3 Plush-crested Jays (Cyanocoraxchrysops), 2 Fawn-breasted Wrens, and 3White-lined Tanagers (Tachyphonus rufus). AtCerro Chovoreca on 22 September 1999, asizeable group of birds was assembled arounda swarm; the following individuals werepresent, among perhaps 10 others: 1 White-barred Piculet (Picumnus cirratus), 2 Black-banded Woodcreepers, 2 Narrow-billedWoodcreepers (Lepidocolaptes angustirostris), 2Bolivian Slaty-Antshrikes, 2 Black-belliedAntwren (Formicivora melanogaster), 1 unidenti-fied tyrannid, and 1 House Wren (Troglodytesaedon).

Migration. Our study period at Cerro Cho-voreca coincided with the arrival of a suite ofspecies that likely represented north-boundaustral migrants. Crowned Slaty Flycatcher(Griseotyrannus aurantioatrocristatus), VermilionFlycatcher (Pyrocephalus rubinus), and Swain-son's Flycatcher (Myiarchus swainsoni) were notrecorded for the first 4–5 days of the Cho-voreca inventory, but were sighted commonlyand in relatively large numbers thereafter; col-lected individuals had heavy subcutaneous fat.Blue-black Grassquit (Volatinia jacarina) andRed-eyed Vireo (Vireo olivaceus) similarly wereunrecorded for 4–5 days, and then becamecommon, but were not collected, so fat levels

could not be confirmed. The latter specieswas collected at Cerro León, and showedenlarged gonads and no fat. Streaked Fly-catcher (Myiodynastes maculatus), althoughsighted on the second day of the Chovorecainventory, increased considerably in abun-dance during the study period. These obser-vations made clear that several species were inthe process of arriving in the Chovoreca areaduring the study period.

The passage of the 28 October 1995atmospheric front at Madrejón also high-lighted the migration of several Nearcticmigrants. This was most evident in the Hirun-dinidae. Immediately after the passage of thefront, the following species and numberswere observed: 20+ Bank Swallows (Ripariariparia), 2 Cliff Swallows (Petrochelidon pyrrho-nota), and 100+ Barn Swallows (Hirundo rus-tica). Other boreal migrants includedMississippi Kite (Ictinia mississippiensis, see Spe-cies accounts), six species of shorebirds(Charadriidae, Scolopacidae; see Appendix 1),and Common Nighthawk (Chordeiles minor).

SPECIES ACCOUNTS

Mississippi Kite (Ictinia mississippiensis). Twoadult kites, that appeared to be moving inassociation with the late October 1995 front,were studied for a few minutes by MBR asthey circled overhead at Madrejón. The rela-tively pale underparts and lack of tail bandsand rufous in the primaries distinguishedthem from Plumbeous Kite (Ictinia plumbea).This sighting and the previous record byBrooks (1997) are the only reports of Missis-sippi Kite from the Alto Chaco region. How-ever, they are not surprising given that thespecies has been found in relatively largenumbers from mid-September through Octo-ber in the Bolivian chaco (Davis 1989). Theextent of the wintering grounds of MississippiKite in southern South America remains tobe delineated.

252

AVIFAUNA OF PARAGUAYAN CHACO

Green-cheeked Parakeet (Pyrrhura molinae).Hayes (1995) evaluated two earlier records ofthis species and concluded that they were toounreliable to document the occurrence ofGreen-cheeked Parakeet in Paraguay. The firstreliable sightings of this species in the countrywere those at Estancia 42 (Capper et al.2001a). Our observations of flocks of up toeight individuals in the tall forest of PicadaChovoreca represent only the second localitywithin the Alto Chaco region. We documentfor the first time the presence of this specieswith specimens and recordings of vocaliza-tions. The specimens (KU 90195, MNHNP;skins) correspond to the subspecies P. molinaesordida, known to occur in adjacent areas ofBrazil and Bolivia (Forshaw 1989, Juniper &Parr 1998).

Pheasant Cuckoo (Dromococcyx phasianellus).We provide the first Paraguay record of thiscuckoo to the west of the Río Paraguay. A sin-gle individual was heard and tape-recorded on20–23 September 1999 in tall forest along Pic-ada Chovoreca. The bird sang actively, but didnot approach in response to playback. Thespecies had not been recorded previouslyfrom the chaco (Short 1975, Hayes 1995,Kratter et al. 1993), though there is at least onesubsequent record from the Matogrosenseregion (RPC).

Ochre-cheeked Spinetail (Poecilurus scutatus).The spinetail was fairly common in the tallforest of Picada Chovoreca. Most individualswere seen foraging in pairs low above ordirectly on the ground. We document thepresence of the species in Paraguay for thefirst time with specimens (KU 90049 and90224, MNHNP; skins, frozen tissues) andsound recordings. Ochre-cheeked Spinetailhas been reported previously in the countryby López (1985) but no details were providedand Hayes (1995) considered the record ashypothetical.

Giant Antshrike (Batara cinerea). We recordedtwo single individuals of this antshrike, sepa-rated by c. 8 km along Picada Chovoreca. Themale was heard singing on two consecutivemornings from a low dense scrub, and onlybriefly climbed to an exposed perch inresponse to playback. The female was seenforaging in vine tangles c. 3 m above a drystream bed within tall forest. Our sightingsbridge the apparent distributional gapbetween the earlier Paraguayan records fur-ther south (Hayes 1995) and Bolivian recordsto the north (Kratter et al. 1993).

Black-bellied Antwren (Formicivora melano-gaster). Prior to our fieldwork this antbirdspecies was only known in Paraguay fromParque Nacional Defensores del Chaco(Madroño et al. 1994, Hayes 1995). Werecorded it at Cerro León in 1995 and atMadrejón in 1999. Outside of Defensores delChaco, a male Black-bellied Antwren wasrecorded by RPC in 1997 at Estancia KambaAka, depto. Alto Paraguay (19°47’S, 58°44’W),while in 1999 the species was found to beabundant along Picada Chovoreca and a pairwas seen on 18 September around Base AéreaAdrián Jara.

Gray-crowned Tyrannulet (Serpophaga grise-iceps). Taxonomy of the Serpophaga subcristata/munda/griseiceps complex is controversial, butthe form recognized by Straneck (1993) as S.griseiceps is gradually gaining acceptance as avalid species. The first report (without details)of this tyrannid in Paraguay would appear tobe that of Contreras (1989) at Estancia Co’ePyahú, depto. Boquerón (20°38’S, 61°57´W).We document for the first time the presenceof Gray-crowned Tyrannulet in Paraguay withtape-recordings of two separate individuals atEstancia 42 on 9 September 1997. Small num-bers of individuals were heard and seen at thissite on most days during fieldwork. The taxonhas since been recorded widely throughout

253

ZYSKOWSKI ET AL.

Paraguay, primarily during the austral winter(RPC).

Plain Inezia (Inezia inornata). We found PlainInezia to be relatively common at CerroLeón, Madrejón and Estancia 42, with a pairobserved copulating at the first site. Hayes(1995) lists this species as “rare” for the AltoChaco region.

Alder Flycatcher (Empidonax alnorum). Twoadults were mist-netted at Cerro León in1995: male on 23 October and female on 24October (MNHNP and KU 87986, respec-tively; skins and frozen tissues). These recordsare the first of this tyrannid for Paraguay andamong the southernmost for the continent(Ridgely & Tudor 1994). Winter distributionsof Alder Flycatcher and its sibling species,Willow Flycatcher (E. traillii) remain poorlyunderstood because they are difficult to iden-tify; usually, the two species are treatedtogether when depicting range maps (e.g.,Ridgely & Tudor 1994, Paynter 1995).

White-naped Xenopsaris (Xenopsaris albi-nucha). A single adult male, foraging silentlyin a leafless tree, at Estancia Triunfo repre-sents the first record of the xenopsaris for theMatogrosense region; however, this wasexpected given that there are several recordsfor the chaco (Hayes 1995) and a recentrecord for the adjacent cerrado (Robbins et al.1999).

DISCUSSION

The existing information regarding the biotaof the Paraguayan chaco is so limited as tobeg very simple questions about the composi-tion of its avifauna. The present surveys offive sites, all brief and at the same season,confirmed the presence of five species for thecountry, two species for the Paraguayanchaco, and 22 species for the regions of Alto

Chaco or Matogrosense. No threatened spe-cies, as defined by BirdLife International(2000), were detected.

Another question is that of the uniformityof the distributions of species across theregion. As suggested by Short (1975), andreinforced by Kratter et al. (1993), speciesturnover in the region is considerable, appar-ently along moisture and vegetation structuregradients. These ideas were further supportedby our results. For example, Pale-crestedWoodpecker, Bolivian Slaty-Antshrike, Black-capped Antwren, Black-tailed Tityra (Tityracayana), Flavescent Warbler (Basileuterus flaveo-lus), and Chestnut-vented Conebill all arepresent at Chovoreca, but absent farthersouth. Spot-winged Falconet (Spiziapteryx cir-cumcinctus), Chaco Earthcreeper (Ochetorhynchuscerthioides), and Stripe-capped Sparrow (Aimo-phila strigiceps) have been found near Filadelfiato the south, and at one site in Bolivia, butnot at any of the sites we surveyed. Moreover,grassland and open habitats were not presentin our study sites, thus we failed to record anumber of species, e.g., Greater Rhea (Rheaamericana), Brushland Tinamou (Nothoproctacinerascens), Red-legged Seriema (Cariama cris-tata), White-banded Mockingbird (Mimus triu-rus), and Wedge-tailed Grass-Finch (Emberi-zoides herbicola), that were recorded by Kratteret al. (1993) and are known from appropriatehabitat just a few hundred kilometers to thesouth in Paraguay.

The results of this study emphasize theneed for large-scale reserves towards theeffective conservation of biodiversity in thechaco. A broad transect of protected areas isthe only strategy that offers promise. Indeedthe Reserva de Biosfera del Chaco representsan impressive first step in this direction: acombination of effective well-planned zoning,strict enforcement of its boundaries and pro-tection against grazing, clearing, and tilling,would make the area one of the premier bioticreserves in southern South America.

254

AVIFAUNA OF PARAGUAYAN CHACO

ACKNOWLEDGMENTS

We thank our field companions FranciscoBrusquetti, Ian Burfield, Pierre Cacciali, DaveCapper, Rosalía Fariña, Corinne Kennedy,Pedro Luis Marti, Mirna Perrens, Rob Pople,and Sergio Villanueva, and in particular driv-ers Pío Angel Amarilla and Lider Hermosa,who made our northern advance possible.Employees of the Dirección de Orde-namiento Ambiental del Paraguay providedmaps, satellite images, and GPS coordinatesof Cerro Chovoreca region. Josephine Pryororganized access to Estancia 42 and the latePaniagua provided logistical support in BahíaNegra during September 1997. The 1995 and1999 expeditions were funded by theNathaniel S. Goss Fund and Panorama Soci-ety Fund of the KU Natural History Museumand the Burroughs Audubon Society. Field-work during September 1997 was primarilyfunded by the BP Conservation Programme,the Lindeth Charitable Trust, the People’sTrust for Endangered Species, and the Gil-christ Educational Trust. We are grateful toDan Brooks and Andy Kratter for improvingthe final manuscript.

REFERENCES

BirdLife International. 2000. Threatened birds ofthe world. Lynx Edicions and BirdLife Interna-tional, Barcelona, Spain, and Cambridge, UK.

Brooks, D. M. 1997. Avian seasonality at a localityin the Central Paraguayan chaco. Hornero 14:193–203.

Capper, D. R., R. P. Clay, A. Madroño N., J. MazarBarnett, I. J. Burfield, E. Z. Esquivel, C. P.Kennedy, M. Perrens, & R. G. Pople. 2001a.First records, noteworthy observations and newdistributional data for birds in Paraguay. Bull.Br. Ornithol. Club 121: 23–37.

Capper, D. R., R. P. Clay, A. Madroño N., & J.Mazar Barnett. 2001b. New information on thedistribution of twenty-two bird species in Para-guay. Ararajuba 9: 57–59.

Clay, R. P., D. R. Capper, J. Mazar Barnett, I. J.

Burfield, E. Z. Esquivel, R. Fariña, C. P.Kennedy, M. Perrens, & R. G. Pople. 1998.White-winged Nightjars Caprimulgus candicansand cerrado conservation: The key findings ofProject Aguara Ñu 1997. Cotinga 9: 52–56.

Contreras, J. R. 1989. La avifauna de la EstanciaCo’e Pyahú y sus cercanías, Nueva Asunción,República del Paraguay. Not. Faun. 17: 1–6.

Davis, S. E. 1989. Migration of the Mississippi KiteIctinia mississippiensis in Bolivia, with commentson I. plumbea. Bull. Br. Ornithol. Club 109: 149–152.

DPNVS (Departamento de Parques Nacionales yVida Silvestre). 1999. Motivos iniciales paraproteger el Parque Nacional Defensores delChaco: Evaluación ecológica rápida. Unpubl.report, Departamento de Parques Nacionales yVida Silvestre, Asunción, Paraguay.

Forshaw, J. M. 1989. Parrots of the world. 3rd ed.Blandford Press, London, UK.

Hayes, F. E. 1995. Status, distribution and biogeog-raphy of the birds of Paraguay. Monogr. FieldOrnithol. 1: 1–230.

Isler, M. L., P. R. Isler, & B. M. Whitney. 1997. Bio-geography and systematics of the Thamnophiluspunctatus (Thamnophilidae) complex. Ornithol.Monogr. 48: 355–381.

Juniper, T., & M. Parr. 1998. Parrots. Yale Univ.Press, New Haven, Connecticut.

Kratter, A. W., T. S. Sillett, R. T. Chesser, J. P.O’Neill, T. A. Parker III, & A. Castillo. 1993.Avifauna of a chaco locality in Bolivia. WilsonBull. 105: 114–141.

López, N. 1985. Avifauna del departamento deAlto Paraguay. Volante Migratorio 4: 9–13.

Madroño N., A. 1995. El chaco Paraguayo: ambi-entes naturales, sus aves y problemas de conser-vación. Cotinga 4: 25–29.

Madroño N., A, J. Abelaira R., & B. Jiménez deMiguel. 1994. Formicivora melanogaster una espe-cie nueva para el Paraguay (Aves: Formicari-idae). Not. Faun. 65: 1–4.

Parker, T. A., III, A. H. Gentry, R. B. Foster, L. H.Emmons, & J. V. Remsen, Jr. 1993. The low-land dry forests of Santa Cruz, Bolivia: A globalconservation priority. Rapid Assessment Pro-gram (RAP) Working Papers No. 4, Conserva-tion International, Washington, DC.

Paynter, R. A., Jr. 1995. Nearctic passerine

255

ZYSKOWSKI ET AL.

migrants in South America. Publ. Nuttall Orni-thol. Club 25: 1–126.

Peterson, A. T., O. A. Flores V., L. S. León P., J. E.Llorente B., M. A. Luis M., A. G. Navarro S.,M. G. Torres C., & I. Vargas F. 1993. Conserva-tion priorities in northern Middle America:Moving up in the world. Biodivers. Lett. 1: 33–38.

Robbins, M. B., R. C. Faucett, & N. H. Rice. 1999.Avifauna of a Paraguayan cerrado locality:Parque Nacional Serranía San Luis, depto. Con-cepción. Wilson Bull. 111: 216–228.

Short, L. L. 1975. A zoogeographic analysis of theSouth American chaco avifauna. Bull. Am.Mus. Nat. Hist. 154: 1–352.

Short, L. L. 1976. Notes on a collection of birdsfrom the Paraguayan chaco. Am. Mus. Novit.2597: 1–16.

Straneck, R. J. 1993. Aportes para la unificación deSerpophaga subcristata y Serpophaga munda, y larevalidación de Serpophaga griseiceps (Aves: Tyr-annidae). Rev. Mus. Argent. Cienc. Natur. “Ber-nardino Rivadavia” 16: 51–63.

Vera, V., F. Barboza, O. Camé, R. P. Clay, A. vanHumbeeck, F. Fracchia, R. Ortiz, G. Terol, & V.Torean. 2000. Iniciativas transfronterizas deconservación en el chaco Paraguayo: Plan deacción de conservación 2000–2004. Unpubl.report, Departamento de Parques Nacionales yVida Silvestre, Asunción, Paraguay.

APPENDIX 1. Species detected at five localities in northern Paraguayan chaco. CL = Cerro León, M =Madrejón. “Doc” indicates the form of documentation for records, including collected (c), photographed(p) and vocal recordings (v).

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocUndulated Tinamou (Crypturellus undulatus)Tataupa Tinamou (Crypturellus tataupa)Neotropic Cormorant (Phalacrocorax brasilianus)Anhinga (Anhinga anhinga)Rufescent Tiger-Heron (Tigrisoma lineatum)Whistling Heron (Syrigma sibilatrix)Cocoi Heron (Ardea cocoi)Great Egret (Ardea alba)Cattle Egret (Bubulcus ibis)Snowy Egret (Egretta thula)Striated Heron (Butorides striatus)Capped Heron (Pilherodius pileatus)Black-crowned Night-Heron (Nycticorax nycticorax)Plumbeous Ibis (Theristicus caerulescens)Roseate Spoonbill (Platalea ajaja)Jabiru (Jabiru mycteria)Wood Stork (Mycteria americana)Maguari Stork (Ciconia maguari)Black Vulture (Coragyps atratus)Turkey Vulture (Cathartes aura)Lesser Yellow-headed Vulture (Cathartes burrovianus)King Vulture (Sarcoramphus papa)Southern Screamer (Chauna torquata)

xx

x

xxx

x

x

x

xxxxx

x

x

xx

xxxxxx

vc

p

v

xx

x

x

xxxx

c

xxx

xxxxxxxxxx

x

xxxxxxxxxx

vv

256

AVIFAUNA OF PARAGUAYAN CHACO

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocRinged Teal (Callonetta leucophrys)Muscovy Duck (Cairina moschata)Brazilian Teal (Amazonetta brasiliensis)Gray-headed Kite (Leptodon cayanensis)Hook-billed Kite (Chondrohierax uncinatus)Swallow-tailed Kite (Elanoides forficatus)Snail Kite (Rostrhamus sociabilis)Mississippi Kite (Ictinia mississippiensis)Plumbeous Kite (Ictinia plumbea)Bicolored Hawk (Accipiter bicolor)Crane Hawk (Geranospiza caerulescens)Great Black-Hawk (Buteogallus urubitinga)Savanna Hawk (Buteogallus meridionalis)Harris's Hawk (Parabuteo unicinctus)Black-collared Hawk (Busarellus nigricollis)Roadside Hawk (Buteo magnirostris)White-tailed Hawk (Buteo albicaudatus)Southern Caracara (Caracara plancus)Yellow-headed Caracara (Milvago chimachima)Chimango Caracara (Milvago chimango)Barred Forest-Falcon (Micrastur ruficollis)Collared Forest-Falcon (Micrastur semitorquatus)Laughing Falcon (Herpetotheres cachinnans)Aplomado Falcon (Falco femoralis)Bat Falcon (Falco rufigularis)Chaco Chachalaca (Ortalis canicollis)Gray-necked Wood-Rail (Aramides cajanea)Giant Wood-Rail (Aramides ypecaha)Limpkin (Aramus guarauna)Black-legged Seriema (Chunga burmeisteri)Southern Lapwing (Vanellus chilensis)American Golden-Plover (Pluvialis dominica)Collared Plover (Charadrius collaris)Wattled Jacana (Jacana jacana)Greater Yellowlegs (Tringa melanoleuca)Lesser Yellowlegs (Tringa flavipes)Solitary Sandpiper (Tringa solitaria)Upland Sandpiper (Bartramia longicauda)White-rumped Sandpiper (Calidris fuscicollis)Picazuro Pigeon (Columba picazuro)Pale-vented Pigeon (Columba cayennensis)Eared Dove (Zenaida auriculata)Scaled Dove (Scardafella squammata)

x

x

xxxxxx

xxxx

x

xx

x

x

x

x

xx

x

xx

xxxxxxx

xx

xx

xx

x

xxxxxxxxx

xx

c

cp,v

c

vv

vc

v

v

xxx

x

xxxxxxx

x

x

ccc

c

c

v

x

xxx

x

xx

xxx

c

c

cv

xxx

x

xxxxx

xx

xx

xx

x

xxx

x

x

x

xxx

257

ZYSKOWSKI ET AL.

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocRuddy Ground-Dove (Columbina talpacoti)Picui Ground-Dove (Columbina picui)Blue Ground-Dove (Claravis pretiosa)White-tipped Dove (Leptotila verreauxi)Yellow-collared Macaw (Primolius auricollis)Blue-crowned Parakeet (Aratinga acuticaudata)White-eyed Parakeet (Aratinga leucophthalmus)Black-hooded Parakeet (Nandayus nenday)Green-cheeked Parakeet (Pyrrhura molinae)Monk Parakeet (Myiopsitta monachus)Yellow-chevroned Parakeet (Brotogeris chiriri)Scaly-headed Parrot (Pionus maximiliani)Blue-fronted Parrot (Amazona aestiva)Dark-billed Cuckoo (Coccyzus melacoryphus)Squirrel Cuckoo (Piaya cayana)Striped Cuckoo (Tapera naevia)Pheasant Cuckoo (Dromococcyx phasianellus)Pavonine Cuckoo (Dromococcyx pavoninus)Greater Ani (Crotophaga major)Smooth-billed Ani (Crotophaga ani)Guira Cuckoo (Guira guira)Tropical Screech-Owl (Otus choliba)Spectacled Owl (Pulsatrix perspicillata)Great Horned-Owl (Bubo virginianus)Ferruginous Pygmy-Owl (Glaucidium brasilianum)Chaco Owl (Strix chacoensis)Common Nighthawk (Chordeiles minor)Pauraque (Nyctidromus albicollis)Rufous Nightjar (Caprimulgus rufus)Little Nightjar (Caprimulgus parvulus)Scissor-tailed Nightjar (Hydropsalis torquata)Common Potoo (Nyctibius griseus)Sick's Swift (Chaetura meridionalis)Unidentified swift (Chaetura sp.)Glittering-bellied Emerald (Chlorostilbon aureoventris)Gilded Hummingbird (Hylocharis chrysura)Blue-tufted Starthroat (Heliomaster furcifer)Blue-crowned Trogon (Trogon curucui)Blue-crowned Motmot (Momotus momota)Ringed Kingfisher (Ceryle torquata)Toco Toucan (Ramphastos toco)White-barred Piculet (Picumnus cirratus)White-fronted Woodpecker (Melanerpes cactorum)

x

x

xx

xx

x

xxxx

xx

x

xx

x

xxx

x

x

x

xx

x

xxx

x

xxxx

xx

x

xxxx

xxx

x

x

v

v

c

c

p,vv

c

cv

cv

c

c

x

xxxx

x

xxx

x

x

xx

xx

xx

xxxxx

x

ccv

c

cc

v

c

c

vc

c

cc

c

x

x

x

x

xx

xx

xx

x

x

x

xx

x

xxx

c

c

c

xxxx

x

x

xx

x

x

xxxxxx

xxxx

x

xxxxx

xx

v

vv

pp

v

p,v

258

AVIFAUNA OF PARAGUAYAN CHACO

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocWhite Woodpecker (Melanerpes candidus)Little Woodpecker (Veniliornis passerinus)Checkered Woodpecker (Picoides mixtus)Green-barred Woodpecker (Colaptes melanochloros)Golden-green Woodpecker (Piculus chrysochloros)Pale-crested Woodpecker (Celeus lugubris)Lineated Woodpecker (Dryocopus lineatus)Crimson-crested Woodpecker (Campephilus melanoleu-

cos)Cream-backed Woodpecker (Campephilus leucopogon)Common Hornero (Furnarius rufus)Crested Hornero (Furnarius cristatus)Chotoy Spinetail (Schoeniophylax phryganophila)Sooty-fronted Spinetail (Synallaxis frontalis)Pale-breasted Spinetail (Synallaxis albescens)White-lored Spinetail (Synallaxis albilora)Ochre-cheeked Spinetail (Poecilurus scutatus)Yellow-chinned Spinetail (Certhiaxis cinnamomea)Stripe-crowned Spinetail (Cranioleuca pyrrhophia)Rufous-fronted Thornbird (Phacellodomus rufifrons)Greater Thornbird (Phacellodomus ruber)Brown Cacholote (Pseudoseisura lophotes)Streaked Xenops (Xenops rutilans)Olivaceous Woodcreeper (Sittasomus griseicapillus)Scimitar-billed Woodcreeper (Drymornis bridgesii)Great Rufous Woodcreeper (Xiphocolaptes major)Black-banded Woodcreeper (Dendrocolaptes picumnus)Narrow-billed Woodcreeper (Lepidocolaptes angustiros-

tris)Red-billed Scythebill (Campylorhamphus trochilirostris)Giant Antshrike (Batara cinerea)Great Antshrike (Taraba major)Barred Antshrike (Thamnophilus doliatus)Variable Antshrike (Thamnophilus caerulescens)Bolivian Slaty-Antshrike (Thamnophilus sticturus)White-backed Fire-eye (Pyriglena leuconota)Mato Grosso Antbird (Cercomacra melanaria)Stripe-backed Antbird (Myrmorchilus strigilatus)Black-capped Antwren (Herpsilochmus atricapillus)Black-bellied Antwren (Formicivora melanogaster)Southern Beardless-Tyrannulet (Camptostoma obsole-

tum)Chaco Suiriri (Suiriri suiriri)

x

xxxx

x

xxx

x

xx

x

xx

xxx

xxx

xxx

xx

x

xxxx

x

xxx

x

xx

ccv

cv

c

c

c

c

vcccv

vvv

c

x

xx

x

x

x

xx

xxx

xxxx

x

xxxx

c

cc

c

c

c

cc

ccc

vvv

c

vcc

x

x

xx

xx

x

x

xx

xx

x

x

x

xxxx

x

v

vc

c

c

c

cc

c

c

c

c

cvcc

c

x

xxxx

xx

xxxx

x

x

xx

xxx

x

xx

xxxx

x

x

v

p,v

p

p,v

pv

vv

p,vp,v

v

259

ZYSKOWSKI ET AL.

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocSouthern Scrub-Flycatcher (Sublegatus modestus)Large Elaenia (Elaenia spectabilis)Small-billed Elaenia (Elaenia parvirostris)White-crested Tyrannulet (Serpophaga subcristata)Gray-crowned Tyrannulet (Serpophaga griseiceps)Plain Inezia (Inezia inornata)Greater Wagtail-Tyrant (Stigmatura budytoides)Tawny-crowned Pygmy-Tyrant (Euscarthmus melory-

phus)Pearly-vented Tody-Tyrant (Hemitriccus margarita-

ceiventer)Yellow-olive Flycatcher (Tolmomyias sulphurescens)Bran-colored Flycatcher (Myiophobus fasciatus)Euler's Flycatcher (Lathrotriccus euleri)Alder Flycatcher (Empidonax alnorum)Fuscous Flycatcher (Cnemotriccus fuscatus)Vermilion Flycatcher (Pyrocephalus rubinus)Cinereous Tyrant (Knipolegus striaticeps)Spectacled Tyrant (Hymenops perspicillatus)Black-backed Water-Tyrant (Fluvicola albiventer)Cattle Tyrant (Machetornis rixosus)Rufous Casiornis (Casiornis rufa)Brown-crested Flycatcher (Myiarchus tyrannulus)Swainson's Flycatcher (Myiarchus swainsoni)Great Kiskadee (Pitangus sulphuratus)Streaked Flycatcher (Myiodynastes maculatus)Variegated Flycatcher (Empidonomus varius)Crowned Slaty Flycatcher (Griseotyrannus aurantioatro-

cristatus)Tropical Kingbird (Tyrannus melancholicus)Fork-tailed Flycatcher (Tyrannus savana)White-naped Xenopsaris (Xenopsaris albinucha)Green-backed Becard (Pachyramphus viridis)Black-tailed Tityra (Tityra cayana)Red-eyed Vireo (Vireo olivaceus)Rufous-browed Peppershrike (Cyclarhis gujanensis)Purplish Jay (Cyanocorax cyanomelas)Plush-crested Jay (Cyanocorax chrysops)Brown-chested Martin (Progne tapera)White-rumped Swallow (Tachycineta leucorrhoa)Southern Rough-winged Swallow (Stelgidopteryx rufi-

collis)Bank Swallow (Riparia riparia)

xx

x

x

x

xxxxx

xxx

xxxxx

x

xx

x

xxxx

x

x

xx

x

xxx

xxxxxxxx

x

xx

xx

xx

x

x

ccc

ccc

c

c

ccc

c

c

cc

cc

c

v

v

x

x

x

x

x

xx

xxx

x

x

xxxxx

c

c

v

c

c

cc

ccc

c

c

cc

x

x

x

x

x

x

xx

x

xx

xxxxx

c

v

c

c

c

c

ccc

xxxx

x

x

x

x

x

x

xxxx

x

x

x

x

xxx

xx

vv

v

p,v

v

v

p,v

c,vp,v

v

v

260

AVIFAUNA OF PARAGUAYAN CHACO

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocCliff Swallow (Petrochelidon pyrrhonota)Barn Swallow (Hirundo rustica)Swallow unidentified (Hirundinidae sp.)Fawn-breasted Wren (Thryothorus guarayanus)House Wren (Troglodytes aedon)Masked Gnatcatcher (Polioptila dumicola)Creamy-bellied Thrush (Turdus amaurochalinus)Rufous-bellied Thrush (Turdus rufiventris)Chalk-browed Mockingbird (Mimus saturninus)Yellowish Pipit (Anthus lutescens)Tropical Parula (Parula pitiayumi)Masked Yellowthroat (Geothlypis aequinoctialis)Flavescent Warbler (Basileuterus flaveolus)Chestnut-vented Conebill (Conirostrum speciosum)Purple-throated Euphonia (Euphonia chlorotica)Sayaca Tanager (Thraupis sayaca)Hooded Tanager (Nemosia pileata)White-lined Tanager (Tachyphonus rufus)Orange-headed Tanager (Thlypopsis sordida)Unidentified tanager (Thraupidae sp.)Grayish Saltator (Saltator coerulescens)Green-winged Saltator (Saltator similis)Golden-billed Saltator (Saltator aurantiirostris)Black-backed Grosbeak (Pheucticus aureoventris)Ultramarine Grosbeak (Cyanocompsa brissonii)Red-crested Cardinal (Paroaria coronata)Yellow-billed Cardinal (Paroaria capitata)Red-crested Finch (Coryphospingus cucullatus)Many-colored Chaco-Finch (Saltatricula multicolor)Blue-black Grassquit (Volatinia jacarina)Saffron-billed Sparrow (Arremon flavirostris)Rusty-collared Seedeater (Sporophila collaris)Double-collared Seedeater (Sporophila caerulescens)White-bellied Seedeater (Sporophila leucoptera)Unidentified seedeater (Sporophila sp.)Dull-colored Grassquit (Tiaris obscura)Saffron Finch (Sicalis flaveola)Black-capped Warbling-Finch (Poospiza melanoleuca)Grassland Sparrow (Ammodramus humeralis)Rufous-collared Sparrow (Zonotrichia capensis)Chestnut-capped Blackbird (Agelaius ruficapillus)Chopi Blackbird (Gnorimopsar chopi)White-browed Blackbird (Sturnella superciliaris)

xxx

xxxx

x

x

xx

x

x

x

xxx

x

x

xx

xxxx

x

x

xxxx

x

x

x

xx

x

x

c

cc

c

c

c

cv

v

c

c

xxxxx

x

xx

xxxx

x

xxxx

x

c

c

c

c

c

cc

v

x

xxx

x

xx

x

x

xxxx

xx

xx

x

x

c

cc

c

c

c

c

c

xx

xxxxx

xxxxxxxxx

xx

xxxxxxxxxx

x

x

x

v

p

v

p

v

p

v

261

ZYSKOWSKI ET AL.

APPENDIX 1. Continuation.

SpeciesDefensores del

ChacoChovoreca Estancia

TriunfoEstancia

42

CL M Doc Doc Doc DocShiny Cowbird (Molothrus bonariensis)Bay-winged Cowbird (Molothrus badius)Epaulet Oriole (Icterus cayanensis)Orange-backed Troupial (Icterus croconotus)Golden-winged Cacique (Cacicus chrysopterus)Solitary Cacique (Cacicus solitarius)Crested Oropendola (Psarocolius decumanus)Hooded Siskin (Carduelis magellanica)

xxxx

x

xc x

x

x

x

xxxx

c

c

c

x

xxx

v

v

262