ORNITOLOGIA NEOTROPICAL 20: 585–595, 2009 © The Neotropical Ornithological Society

DISTRIBUTIONS OF THREATENED OF , AND , WITH NEW LOCALITY RECORDS AND NOTES ON THEIR NATURAL HISTORY AND HABITAT

Mariano Codesido1,2 & Rosendo Manuel Fraga³

1Departamento de Ecología, Genética y Evolución, FCEN, Universidad de , Ciudad Universitaria, Pabellón II, 4to. piso, Ciudad Autónoma de Buenos Aires (C1428EHA), Argentina. 2Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina. E-mail: [email protected] ³CICYTTP-CONICET, España y Matteri, (3105) Diamante, Entre Ríos, Argentina.

Resumen. – Distribuciones de paseriformes amenazados de pastizal de Paraguay, Argentina y Uruguay, con registros de nuevas localidades y notas de su historia natural y hábitat. – Se repor- tan nuevas localidades para ocho especies de pastizal globalmente amenazadas y dos casi amenaza- das de Paraguay, Argentina y Uruguay, con notas de su historia natural y hábitat. Los muestreos se llevaron a cabo entre Agosto de 2001 hasta Marzo de 2004. Las especies estudiadas fueron el Yetapá Chico (Alectrurus tricolor), el Yetapá de Collar (A. risora), la Monjita Dominica ( dominicanus), el Tachurí Canela ( pectoralis), el Tachurí Coludo (Culicivora caudacuta), la Cachirla Dorada (Anthus nattereri), el Capuchino Garganta Café ( ruficollis), el Capuchino Pecho Blanco (S. palustris), el Capuchino Corona Gris (S. cinammomea) y el Tordo Amarillo (Xanthopsar flavus). Para alguna especies se confirma una distribución restringida y fragmentada. La mayoría de nuestros regis- tros se obtuvieron en pasturas naturales ligera o moderadamente pastoreadas por ganado. Este hábitat seminatural está volviéndose escaso en toda la región.

Abstract. – We studied the distribution of eight species of globally threatened and two near-threatened grassland passerines from Paraguay, northeastern Argentina, and Uruguay and gathered data on their natural history and habitat requirements. The records were obtained during surveys conducted between August 2001 and March 2004. The target species were Cock- and Strange-tailed Tyrants (Alectrurus tri- color, A. risora), Black-and-white Monjita (Xolmis dominicanus), Bearded Tachuri (Polystictus pectoralis), Sharp-tailed Tyrant (Culicivora caudacuta), Ochre-breasted Pipit (Anthus nattereri), Dark-throated Seed- eater (Sporophila ruficollis), (S. palustris), (S. cinammomea), and Saffron-cowled Blackbird (Xanthopsar flavus). We confirm the previously supposed restricted and frag- mented distribution of several species. Most target species occur in natural pastures with light to moder- ate grazing by livestock, a habitat increasingly scarce in the region. Accepted 20 October 2009.

Key words: Threatened passerines, native , Argentina, Paraguay, Uruguay.

INTRODUCTION and livestock raising (Stotz et al. 1996, Nern- berg & Ingstrup 2005, Askins et al. 2007). As Natural grasslands throughout the Americas a consequence, many of the native spe- have been drastically altered for agricultural cies confined to natural grasslands have suf-

585 CODESIDO & FRAGA fered population declines or range reduction. Marsh Seedeater (S. palustris), Chestnut Seed- These are now either regarded as glo- eater (S. cinnamomea), and Saffron-cowled bally threatened (BirdLife International 2008), Blackbird in Paraguay, Argentina, and Uru- or considered of high conservation priority guay. BirdLife International (2008) considers (Stotz et al. 1996). Habitat loss and degrada- all ten species to be globally threatened or tion are widely believed to be the main causes near threatened. Whenever possible, we com- of avian extinction and declines (Stotz et al. pared our distributional data with historical 1996, Birdlife International 2008). This also records of the species obtained from the liter- applies to the native avifauna of the extensive ature (Collar et al. 1992) and museum speci- natural grasslands of South America (Bucher mens. Our second objective was to obtain & Nores 1988, Vickery et al. 1999, Di Gia- data on habitats used by the target species, como & Krapovickas 2005). For this conti- because precise information on the subject is nent, however, we often lack important life often lacking. As a third objective, we evalu- history and ecological information about how ated the potential effects of recent changes in habitat modifications are negatively affecting land use, particularly due to intensive agricul- the populations of grassland birds. ture and forestry on this species, and collected In the southern grasslands of South natural history information relevant to their America, populations of 11 passerines are conservation. classified as globally threatened and another five as near-threatened (BirdLife International METHODS 2008) because of reduced population sizes or restricted distributions (Mace et al. 1992). The survey area is located within the region Since reliable population estimates are not named “Mesopotamian grasslands” by Stat- available for most South American birds, tersfield et al. (1998). This region covers about many distributional ranges can be estimated 160,000 km² in eastern South America and is only from locality records. A comparison of surrounded by important rivers like the past and present distributions has shown Paraná, Paraguay and Uruguay. It includes range declines of 50–80 % for grassland spe- mostly lowlands, bordering hilly country only cies, such as the Strange-tailed Tyrant (Alectru- at its northern edge in Paraguay and Argen- rus risora), the Saffron-cowled Blackbird tina. The climate ranges from warm temper- (Xanthopsar flavus), and the Meadow- ate to subtropical with abundant rainfall, lark (Sturnella defilippii) (Fraga et al. 1998, mostly during the Austral spring and summer. Tubaro & Gabelli 1999, Di Giacomo & Di Within Argentina, the region has been subdi- Giacomo 2004). Thus, locality records vided by Burkart et al. (1999) as including the become an important tool for assessing the eco-regions of the Pampas, Campos y Maleza- conservation status of declining species les, and Esteros del Iberá. Similar vegetation (Mace et al. 1992). zones occur in southern Paraguay, such as at Our first objective was to obtain new the Campos de las Misiones and the Esteros information on the current distributions of del Ñeembucú (Cabrera 1970, Hayes 1995). Cock-tailed Tyrant (Alectrurus tricolor), Strange- The main natural vegetation types of the tailed Tyrant, Black-and-white Monjita (Xol- Mesopotamian region are grasslands and mis dominicanus), Bearded Tachuri (Polystictus marshes (Burkart et al. 1999). In Paraguay and pectoralis), Sharp-tailed Tyrant (Culicivora cauda- northeastern Argentina, the extension of cuta), Ochre-breasted Pipit (Anthus nattereri), grasslands is limited by the subtropical Atlan- Dark-throated Seedeater (Sporophila ruficollis), tic Forest (Esquivel et al. 2007). Within the

586 THREATENED GRASSLAND PASSERINES area mapped by Stattersfield et al. (1998), colored and/or conspicuous in open habitats extensive areas of thorny woodland of Prosopis (Ridgely & Tudor 1989, 1994). Visual records spp., Scutia buxifolia, Schinus longifolius, Celtis were obtained with binoculars and cameras tala, and Acacia spp. occur in northern Entre and bird vocalizations were recorded with Ríos and southern provinces and Sony Walkman Pro or Marantz cassette extend into nearby Uruguay (Cabrera 1976, recorders using a shotgun microphone (AKG Carnevali 1994, Burkart et al. 1999). For rea- C568 EB). Many bird vocalizations obtained son of this different vegetation type we did during the surveys are available in López- not conduct grassland bird surveys in this area Lanús (2008). Coordinates were obtained with (Fig. 1). The Mesopotamian grasslands were a GPS unit. Localities were considered differ- devoted mostly to cattle grazing soon after ent if they were separated by a minimum of 10 the European colonization (Di Pace 1992) km (Fraga et al. 1998). Historical records from and agriculture started to expand after the museum specimens were mostly obtained 1950s. from the Museo Argentino de Ciencias Natu- Earlier records cited in this paper were rales in Buenos Aires (MACN). Whenever obtained during the authors’ residence in Pa- possible, museum specimens were checked to raguay (2001–2002). Our most extensive sur- avoid perpetuating misidentifications (e.g., veys with 63 days of field work were Fraga 2008). Scientific and English nomencla- conducted between April 2003 and March ture follow Remsen et al. (2009). 2004. Surveys were conducted during April, July, August, November, December, and RESULTS March covering the four seasons (details of dates and itineraries are available from the Of the ten target species, eight are globally authors). We located birds mostly by slowly threatened and two are near-threatened driving along rural dirt roads of a total length (BirdLife International 2008). Of the first, of 5000 km but also by visiting estancias one species is classified as endangered and (ranches) along our routes. seven are considered vulnerable. We conducted surveys within the follow- ing political subdivisions: in Paraguay, depar- Cock-tailed Tyrant (Vulnerable). This flycatcher tamentos Guairá, Paraguarí, Ñeembucú, was only observed in Paraguay, although we Misiones, Itapúa and Caazapá; in Argentina, surveyed its historical range in Argentina. It is the provinces of Misiones (departamento considered “rare” in Paraguay (Guyra Para- Posadas), Corrientes (departamentos Ituza- guay 2004), and we saw it at two localities ingó, Santo Tomé, Alvear, San Martín and without previous records. The first new local- ) and Entre Ríos (departa- ity was Estancia La Yegreña (departamento mentos Colón, Gualeguay, Tala, Concepción Itapúa). Here, in October 2002 we detected a del Uruguay, Gualeguaychú, and Islas del minimum of 12 males perched or displaying Ibicuy), and in Uruguay departamentos So- in 20 ha of native grassland. This grassland riano, Río Negro, and Paysandú (Fig. 1). patch was up to 1.60 m tall, lush, and lightly Details on localities and dates can be found in grazed by a few cattle. About three females the Appendix. were glimpsed perched low in the dense vege- Both authors had previous experience tation; because of the season, they were possi- with the areas surveyed and knowledge of bly nesting. At the second new locality, their avifauna (e.g., Fraga et al. 2003). Other Estancia Isla Alta (departamento Misiones), than the pipit, the target species are strikingly the grasslands were drier and heavily grazed.

587 CODESIDO & FRAGA

FIG. 1. Distribution of natural grasslands in gray (mostly after Burkart et al. 1999) and survey localities in Paraguay, Argentina, and Uruguay. The detailed map shows the new localities (*) and the departamentos in each country covered by our surveys. Initials correspond to departamentos: NE: Ñeembucú; PR: Para- guari, MI: Misiones; CA: Caazapá; IT: Itapúa, Paraguay; PO: Posadas, IZ: Ituzaingó; ST: Santo Tomé; AV: Alvear; SM: San Martín; GU: Gualeguaychú; GY: Gualeguay; TA: Tala; CU: Concepción del Uruguay; IB: Ibicuí, Argentina, and PA: Paysandú; RN: Río Negro; SO: Soriano, Uruguay.

In August 2003, one displaying male and two were previously reported (Di Giácomo & Di females were observed. In March 2004, one Giácomo 2004), but less information was single immature male was seen in a second available for Paraguay. Strange-tailed Tyrants visit. The difference in numbers between the were particularly common along the dirt road two localities probably reflects grazing condi- connecting San Juan Bautista and the arroyo tions, because the first site was surveyed for 6 Aguaray, (departamento Ñeembucú), Para- h just one day whereas the second site was guay. A minimum of 17 males and females visited on two different days with more than were detected along 20 km of road. This 10 h of observations. Esquivel et al. (2007), locality was already reported by Ridgely & describe other current Paraguayan localities Tudor (1994) and retains good grassland hab- for this tyrant. itat. We recorded single individuals at two other sites, a female at Estancia La Graciela Strange-tailed Tyrant (Vulnerable). We only ob- (departamento Misiones) and a young male in served this species in Corrientes (Argentina) grasslands adjoining rice fields at the property and Paraguay. Our localities for Corrientes of the Oest family (departamento Caazapá).

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Black-and-white Monjita (Vulnerable). This spe- men del Paraná (departamento Itapúa). In cies is considered “hypothetical” in Paraguay March 2003, we saw three pairs at Estancia (Hayes 1995, Guyrá Paraguay 2004). Hence a Roa Cué (departamento Caazapá). The habitat priority of our surveys was to uncover its dis- in the three sites was flooded grassland. In tributional status for Paraguay. Although we Argentina, in July 2003, we observed a pair in searched in habitats similar to those used by tall Andropogon lateralis grassland near Monte the species in Argentina (Fraga 2003) we Mberity (departamento Santo Tomé, Corri- failed to detect the species even at sites sepa- entes). rated 15–30 km (the Parana river valley) from known Argentinean populations. In Paraguay, Ochre-breasted Pipit (Vulnerable). This pipit was we surveyed Lago Ypoá, Isla Yaciretá and located mostly by its distinctive songs, which Carmen del Paraná (see Appendix). were tape-recorded. Ochre-breasted Pipits In Corrientes province, Argentina, we commonly sing during aerial displays in late found Black-and-white Monjitas at two locali- winter and spring (Fraga 2001) but may be ties not reported in Fraga (2003). These silent in late summer and fall. Our records for records extend its known distribution south eastern Paraguay extend its known distribu- along the Aguapey River to Bañado Santa tion to the west and south within the country, Rosa (departamento Alvear) and Estancia San with two new localities, Estancia Lago Ypoa Jorge (departamento San Martin). In Entre (departamento Paraguarí) and Estancia Guazú Ríos province we found the species at just one Cuá (departamento Ñeembucu). In Argen- locality not reported in Fraga (2003), at tina, it was only observed in Corrientes prov- Estancia La Calera, where two territorial pairs ince where we found three new localities: near were simultaneously observed. In western Monte Mberity, Estancia El Triunfo (depar- Uruguay we found monjitas at one locality, tamento Santo Tomé), and Estancia Santa Isa- an unnamed estancia near Quebrachos, depar- bel (departamento Alvear). These records tamento Paysandú. The Uruguayan site extend the southern distributional limit in of Quebrachos was recorded as a monjita Argentina to 28°34’S. In all localities, we locality in November 1966 (Gore & Gepp found this pipit relatively abundant in natural 1978). pastures in dry soil. The pastures were grazed, less than 20 cm high, and subject to seasonal Bearded Tachuri (Near Threatened). The species fires to encourage fresh growth of grass. was only observed in Entre Ríos province, Argentina. We found at least five males per- Dark-throated Seedeater (Near Threatened). We forming aerial displays in pastures along rural found a mixed flock of 100+ individual seed- roads near Estancia El Potrero, departamento eaters in March 2004 near Arroyo Aguaray Gualeguaychú, in November 2003. The habi- (departamento Ñeembucú). Adult males com- tat comprised natural pastures in dry soil prised about 20% of the flock and included invaded by native woody shrubs like Dodonea those of Dark-throated Seedeaters. Other spp. (Sapindaceae) and Baccharis spp. (Aste- adult males in the flock were of Rusty-col- raceae). lared, Double-collared, Tawny-bellied, Marsh, Chestnut and Capped Seedeaters (S. collaris, S. Sharp-tailed Tyrant (Vulnerable). This small fly- caeruslescens, S. hypoxantha, S. palustris, S. cinna- catcher was detected in Paraguay at three momea and S. bouvreuil, respectively). We think localities. In August and September 2001, sin- that this flock was migrating north at the end gle pairs were seen at Isla Yacyretá and Car- of the Austral summer. The habitat was native

589 CODESIDO & FRAGA grasslands growing on roadside ditches. (Hayes 1995, Guyra Paraguay 2004) where the Mixed flocks of seedeaters have been species had not been reported, without find- reported by other authors and depicted in ing blackbirds. However, we found new local- field guides (Narosky & Yzurieta 1987). ities for this icterid in the middle and upper We saw a minimum of three pairs in pas- basin of the Río Tebicuary, a main eastern tures along the edges of rural roads, near tributary of the Río Paraguay. The western- Estancia El Potrero, departamente Guale- most locality along this river was Estancia La guaychú, Entre Ríos province, Argentina, Graciela (departamento Misiones) where we during the Austral spring, in November 2003. repeatedly found blackbirds in small flocks ≤ The habitat was the same as for the Bearded 40 individuals. We obtained several new local- Tachuri. Three singing males were observed ities in the middle basin in the vast depression at Reserva Privada Malabrigo, in the same drained by the Arroyo Guajhó north of Yuty departamento, in December 2003. The habi- (departamento Caazapá). This depression tat was a small grassy clearing in a regenerat- contains marshes, wet natural pastures, and ing Acacia spp. woodland. In Uruguay, we rice-fields and extends west to the Río Pirapó, detected several singing males of this seed- another tributary of the Tebicuary. We found eater, including a male in immature plumage, five Xanthopsar flocks or groups on the prop- in an estancia near Quebrachos, Paysandú, in erty of the Oest family (Caazapá), with a total November 2003. The habitat was a rural of about 60 individuals. This locality had roadside with a mixture of grassland and blackbirds when surveyed in a previous Para- weeds growing on dry soil. guay trip in April 2002, indicating that it is important to the species. About 300 Saffron- Marsh Seedeater (Endangered). The only individ- cowled blackbirds were seen at Estancia uals observed in Paraguay were three males in Roa Cué in Caazapá during a survey in April the previously described mixed flock near the 2002, the second largest flock reported for Arroyo Aguaray (departamento Ñeembucú). the species in Paraguay (MC pers. observ.). We saw two singing males of this species in The Estancia subsequently changed adminis- marshy Panicum spp. grassland at Estero Santa trators, and on a later trip in March 2004 Rosa (departamento Alvear), in Corrientes most natural pastures had been replaced by province, Argentina, during the Austral spring soybean and corn crops. We found 60 black- in December 2003. birds at a woodland edge near the soybean fields. Chestnut seedeater (Vulnerable). In Paraguay, we We found this blackbird at three new only observed males in the previously localities in Corrientes province, Argentina. described mixed flock near the Arroyo We found a wintering roost of about 240 Aguaray (departamento Ñeembucú). We blackbirds on shrubs along a rural road near found one male near the Arroyo Bellaco Estancia La Guayna in July 2003, the highest (departamento Río Negro) in western Uru- number we have ever recorded in Argentina. guay in November 2003. The habitat was a Two localities along the provincial route 39 roadside humid grassland with Lolium spp. were new, Estancia Santa Isabel and Bañado and Eryngium spp. Santa Rosa, with a total of about 30 individu- als. The new sites were in marshy natural pas- Saffron-cowled Blackbird (Vulnerable). We tures along the lower Río Aguapey, a main explored the departaments in the southeast- tributary of the Río Uruguay. We found three ern eco-region of Ñeembucú, in Paraguay new localites for the species in Entre Ríos. We

590 THREATENED GRASSLAND PASSERINES observed a breeding group of 32 individuals distributions for Black-and-white Monjita in a marsh at Estancia La Calera (departa- (Fraga 2003) and Saffron-cowled Blackbirds mento Gualeguaychú). Another important (Fraga et al. 1998) in Argentina. We think that site was Ibicuy (departamento Islas de Ibicuy), the extensive thorn woodlands in northern which is somewhat isolated from the remain- Entre Ríos and southern Corrientes do not ing distributional range. Saffron-cowled provide a suitable natural habitat for these Blackbirds were observed in all three trips to two open country species. this site, with a maximum of 76 individuals. Most species surveyed were seen only in The habitat was mostly cattle pasture of native natural pastures, lightly to moderately grazed grass species. Ibicuy is important because its by livestock. This was particularly true for the proximity to , where two Alectrurus tyrants. Ochre-breasted Pipits the blackbirds have not been seen since 1932 apparently tolerate higher grazing pressures (Fraga et al. 1998). We observed a single pair than the tyrants. Some tolerance of grazing by at Reserva Privada Malabrigo (departamento our target species was expected on historical Gualeguaychú), but the observation was not grounds. Cattle and horses were introduced in repeated in many subsequently visits to this the region by the first Spanish settlers in the place. We were unable to find Saffron-cowled 16th century. Over time, large semi-feral pop- Blackbirds in western Uruguay, although our ulations of cattle and horses formed (Soriano surveys there were as extensive and careful as 1991, Carnevali 1994). The Jesuitic missions those in Entre Ríos province, Argentina. of eastern Paraguay and Corrientes had accu- mulated 744,000 heads of cattle and oxen, DISCUSSION 167,000 horses, and 226,000 sheep by 1768 (Carnevali 1994). The threatened grassland We present 16 new localities for ten threat- passerines of today have survived a period of ened grassland passerines from Argentina, extensive, moderate grazing by livestock on Uruguay, and Paraguay. The lack of records large tracts of land (estancias, vaquerías) as for the Cock-tailed Tyrant from Argentina, practiced throughout the Spanish colonial where it was known from a few historical period and up to the last century. The current localities in Corrientes and Misiones prov- agricultural impact on the Rio de la Plata inces (chiefly specimens from the 1960’s at grasslands started with a wave of European the MACN), suggests its probable extinction colonization in the 1870’s (Bucher & Nores in that country. Our findings revealed that the 1988). By the 1920’s a negative effect of agri- distribution of Ochre-breasted Pipits was culture was reported for the Strange-tailed underestimated. This relatively cryptic spe- Tyrant in Argentina (Wilson 1926). cies has a larger range than previously sug- Most of our records were obtained in nat- gested and has been recently reported for ural grassland. Comparisons of our observa- northern Uruguay (Azpiroz & Menéndez tions with historical records suggest that well 2008). Currently it is considered vulnerable, preserved natural grasslands have been sup- mostly because of its rarity in (BirdLife porting many of our target species for pro- International 2008). We added a few new longed periods. Black-and-white Monjita have localities for the remaining passerines, but the persisted at Quebrachos, Uruguay, for at least slightly enlarged distributions do not substan- 36 years. Saffron-cowled Blackbirds may tially differ from the recent ranges reported show a similar pattern. One locality, Estancia by Collar et al. (1992) or BirdLife International Mora Cué in Corrientes, has at least 11 years (2008). Our findings confirm the fragmented of blackbird breeding records (from 1995 to

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2006; Fraga et al. 1998). However, some of the Negro (Paruelo et al. 2006) where several of target species also use agricultural land or the target species had historical records other man-made habitats. Saffron-cowled (Azpiroz 2003). Blackbirds foraged and nested in wheat fields Few national parks or provincial reserves in Entre Ríos province (Fraga et al. 1998) and protect large tracts of natural grasslands in also in nearby Uruguay (Gore & Gepp 1978). our study area. Unless this situation is The blackbirds commonly foraged and nested reversed, most of the target species will only in abandoned rice-fields in Paraguay and Co- survive in remote and isolated areas devoted rrientes. Abandoned rice-fields also provided to traditional cattle raising, but those areas are habitat for Black-and-white Monjita and sev- becoming fewer and smaller (Paruelo et al. eral species of breeding and migrating seed- 2006) and the remaining populations might eaters. Chestnut and Marsh seedeaters also therefore face extinction. occupied small man-made patches of native grasses, particularly with Erianthus spp. and ACKNOWLEDGMENTS Paspalum spp. growing along drainage ditches or marshy roadsides. Our surveys were financed by the World Bank Recently, natural pastures have also been and the secretary’s office of United Nations replaced with intensive agriculture, particu- Convention on Migratory Species. Within the larly with soybean crops, and with the exten- latter organization we thank Dr. Marco Bar- sive plantations of exotic Pinus and bieri. In South America, we received support trees. Soybean agriculture has occupied the from V. Lichtschein and S. Goldfeder (Coor- most fertile upland soils in Argentina and dinación de Conservación de la Biodiver- Uruguay (Paruelo et al. 2006) and is steadily sidad, Secretaría de Ambiente y Desarrollo advancing in central Paraguay. Forestry has Sustentable, Argentina) and A. Yanosky, S. been developed particularly in Corrientes and Villanueva, H. del Castillo, and R. Clay (Aso- in Uruguay. Argentinean government sources ciación Guyra Paraguay, Paraguay). D. Bilenca, have reported 330,000 ha of plantations in P. Vickery, and I. Areta provided helpful Corrientes province with pines covering comments on drafts of this manuscript. about 60% of this area (Secretaría de Ambi- Many people helped us during the surveys, ente y Desarrollo Sustentable 2004). These particularly J. Vizcaichipi, A. Garello, and M. plantations occupy former natural pastures Kondstant. with acid soils, particularly in the northeast along the Río Uruguay (pers. observ.). For REFERENCES instance, Saffron-cowled Blackbird popula- tions may be now extinct in this zone, at Askins, R., F. Chavez-Ramirez, R. Dale, C. Haas, J. Estancia Rincón de las Mercedes (28°19’S, Herkert, F. Knopf, & P. Vickery. 2007. Conser- 55°46’W) blackbirds were collected in 1962 vation of grassland birds in North America: (specimens at MACN). The senior author understanding ecological processes in different observed a small blackbird flock at this local- regions. Ornithol. Monogr.: 64: 1–46. Azpiroz, A. B. 2003. Aves del Uruguay. Lista e ity in 1997 in a pasture patch partially sur- introducción a su biología y conservación. Edi- rounded by pine plantations. Since then, there torial Graphis, Montevideo, Uruguay. have been no reports by us or by other Azpiroz, A. B., & J. L. Menéndez. 2008. Three new researchers. In Uruguay, pine and eucalypt species and novel distributional information plantations now cover 35% of the combined for birds in Uruguay. Bull. Br. Ornithol. Club area of the departamentos Paysandú and Río 128: 38–56.

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594 THREATENED GRASSLAND BIRDS Xf Jul Dec Dec Xanthopsar Mar, Aug Mar, Aug Mar, Aug Mar, Xolmis dominica- Xolmis , Xf: Sc Mar Nov ; Xd: Sp Mar Dec Sr Mar Nov Nov Nov Jul Alectrurus risora An Sporophila cinnamomea Mar Aug Dec Nov ; Ar: ; Sc: Jul Cc Sep Mar Aug Species¹ Pp Nov Nov Nov Alectrurus tricolor Jul Xd Apr Dec Sporophila palustris Nov Jul, Dec ; Sp: Ar Mar Mar Dec At Oct Mar, Aug Mar, Sporophila ruficollis ; Sr: 56°43'W 56°08'W Longitude 57°24'44"W 57°30'23"W 57°59'28"W 56°43'17"W 56°49'19"W 56°00'12"W 56°06'56"W 56°18'00"W 56°04'07"W 56°15'00"W 56°08'15"W 56°32'49"W 56°34'13"W 56°40'57"W 58°25'36"W 58°36'25"W 58°45'50"W 59°06'01"W 57°51'15"W 58°04'22"W r the target species during the surveys. ¹At: Anthus nattereri ; An: 27°25'S 27°15'S Latitude 25°59'57"S 26°52'49"S 26°52'20"S 26°45'45"S 26°34'54"S 26°43'08"S 26°33'23"S 26°29'33"S 27°45'44"S 28°25'24"S 28°37'49"S 28°34'35"S 28°57'04"S 28°58'27"S 32°57'42"S 33°24'30"S 32°54'06"S 33°43'45"S 32°01'55"S 32°35'10"S Itapúa Itapúa Itapúa Alvear Alvear Caazapá Caazapá Culicivora caudacuta Misiones Misiones Paraguarí Paysandú Ituzaingó Río Negro San Martin Ñeembucú Ñeembucú Santo Tomé Santo Tomé Department Gualeguaychú Gualeguaychú Gualeguaychú Islas de Ibicuy ; Cc: Polystictus pectoralis Polystictus

Estancia Lago Ypoa Aguaray Arroyo EstanciaCuá Guazú Estancia Isla Alta Estancia La Graciela Yaciretá Isla Estancia La Yegreña Carmen del Paraná Cué Estancia Roa Arrozal Oest Estancia La Guayna Near Monte Mberity Estancia El Triunfo EstanciaIsabel Santa Bañado Santa Rosa Estancia San Jorge Estancia El Potrero Estancia La Calera Reserva Malabrigo Ibicuy Quebrachos Arroyo Bellaco ; Pp: Country - locality PARAGUAY ARGENTINA Corrientes Province Province Ríos Entre URUGUAY APPENDIX. New locations and months of records fo nus flavus.

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