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ORNITOLOGIA NEOTROPICAL 18: 627–633, 2007 © The Neotropical Ornithological Society

DISTRIBUTION AND HABITAT PREFERENCES OF THE SOUTHERN (CORYTHOPIS DELALANDI) IN THE AUSTRAL YUNGAS OF AND

María Eva Alvarez1 & Pedro G. Blendinger1,2

1Laboratorio de Investigaciones Ecológicas de las Yungas (LIEY), Universidad Nacional de Tucumán. CC 34, (4107) Yerba Buena, Tucumán, Argentina. E-mail: [email protected] 2Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina.

Distribución y preferencias de hábitat del Mosquitero (Corythopis delalandi) en las Yungas Aus- trales de Bolivia y Argentina. Key words: Argentina, Bolivia, Corythopis delalandi, habitat preference, premontane forest, Southern Antpipit, Yungas forest.

INTRODUCTION tral Yungas, but they include it as “accidental, registered only few times or with historical The currently known distribution of the records”. Other general works on Argen- Southern Antpipit (Corythopis delalandi) ranges tinean avifauna do not mention this species from southern to eastern , for northwestern Argentina. Here we report northeastern Argentina and east of Bolivia new distribution records of the Southern (Ridgely & Tudor 1994, Fitzpatrick 2004). Antpipit for the Austral Yungas in southern According to the most recent review of the Bolivia and northwestern Argentina and we Tyrannidae family, this species is distributed analyze its habitat preferences in this area. towards the east of the department of Santa Cruz in Bolivia (Fitzpatrick 2004), where it METHODS has been found in gallery forests and lowland evergreen forests from 400 to 700 m (Hen- We conducted observations in the Austral nessey et al. 2003). Although Narosky & Yzu- Yungas or Selva Tucumano-Boliviana that rieta (1987) considered this species as extends as a narrow latitudinal strip between “occasional or with doubts” for northwestern 19 y 28°S along the eastern slopes of the Argentina in the last revised edition of their Bolivian and Argentinean Andes (Brown et al. book, they excluded it from the region 2001, Navarro & Maldonado 2002). Observa- (Narosky & Yzurieta 2003). Mazar Barnett & tions were conducted during numerous trips Pearman (2001) do not consider the Southern to more than 40 localities between January Antpipit as a species characteristic of the Aus- 2001 and September 2006. All records corre-

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FIG. 1. Map of the Austral Yungas showing the premontane forest (dark grey), the new distribution records (black dots) of the Southern Antpipit, and additional records (black triangles) by Olrog (1979), Rivero et al. (2004), and L. Rivera (pers. com.). The enlarged region of the Tartagal mountain range shows the distribution of Southern Antpipits (black stars) and location of point counts (grey dots) conducted during spring; schematic distribution of medium-size creeks preferred by the species is indicated (see text). spond to the lower altitudinal belt, the pre- we visited several localities during the same montane forest (Fig. 1), a region characterized study period. floristically (Cabrera 1976, Prado 2000). In In 2004 and 2005, we conducted a more Argentina, this forest is found from 300 m in intensive survey in the Tartagal mountain the lowlands up to 700 m, reaching locally up range, Salta province, Argentina, close to the to 1000 m (Brown et al. 2001, in press). In Bolivian border. Within a 315,000 ha area, we Bolivia, the premontane forest is found selected 11 sampling sites on the condition mostly from 600 to 800 m elevation, and use that they covered the major forest types and to be considered together with other driest the complete elevation range. Topography in forest in the Chaco Serrano region (Ibisch et the area is heterogeneous, with few flat areas al. 2003) more than in the Selva Tucumano- at the bottom of narrow valleys and along the Boliviana. We never recorded the Southern main rivers (Blendinger et al. in press a). The Antpipit in higher altitudinal belts (i.e., mon- dominant vegetation is a deciduous forest tane forests) of the Austral Yungas, although with Anadenanthera colubrina, Callycophyllum

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TABLE 1. Recording localities of Southern Antpipits in the Premontane Forest of Austral Yungas from Bolivia and Argentina.

Localities Latitud Longitud Elevation Date Yumao, dep. Santa Cruz, Bolivia 19°10'S 63°35'W 715 m Jan 2003 Caiza, dep. Tarija, Bolivia 21°53'S 63°41'W 754 m Jan 2003 Macueta Norte, prov. Salta, Argentina 22°01'S 63°54'W 1110 m Aug 2004, Oct 2005 Campo Largo, prov. Salta, Argentina 22°02'S 63°56'W 700 m Oct 2005 Arroyo Aguay, prov. Salta, Argentina 22°31'S 63°54'W 679 m Oct 2005 Finca Falcón, prov. Salta, Argentina 22°19'S 63°58'W 679 m Nov 2004, Oct 2005 Río Seco, prov. Salta, Argentina 22°33'S 63°58'W 555 m Nov 2005 Abra Grande, prov. Salta, Argentina 22°06'S 64°25'W 430 m Jan 2001 Finca Alto Verde, prov. Salta, Argentina 22°21'S 64°54'W 692 m Sep 2006 multiflorum, Phyllostylon rhamnoides and Eryotheca rectional Sennheiser microphone and a roseorum as the most characteristic tree species, Marantz PMD 222 tape recorder. All sound with an open understory and only leaf litter at recordings were later analyzed to corroborate ground level. In more humid sites such as less field identifications and to determine the exposed slopes and in narrow gorges with presence or absence of Southern Antpipits. creeks, the vegetation is dominated by ever- For each point count, we recorded its location green tree species as Cinnamomum porphyria, on the slopes, type of forest, percent of Ocotea puberula, Chrysophyllum gonocarpum, mature and secondary forest, and distance to Blepharocalix salicifolius, Diatenopteryx sorbifolia human created edges; all points were geo- and Cupania vernalis, with a denser understory graphically referenced and incorporated to a than in deciduous forests and herbaceous geographic information system. By visual cover at ground level. The conservation status interpretation of a Landsat image taken on 3 of the area is relatively good compared with May 2005, we established the extension of other premontane forest areas of northwest- Austral Yungas forests in the Tartagal and ern Argentina (Blendinger et al. in press b). As Alto Río Seco mountain ranges, and we used part of a larger study, at each of these 11 sites an overlay of digital elevation model with a 40 we conducted 30 point counts at least 200 m m cell resolution to classify watersheds size, to apart. Distance from observer was recorded estimate their length and to delimit a buffer for all with an accuracy of 10 m; never- area of 100 m at each side of each river. For all theless, the number of detections was insuffi- spatial analyses we used Arc GIS v. 9 Spatial cient for estimating Southern Antpipit density Analyst (ESRI 2005). with distance methods. Thus, all detections within a 50-m radius around the observer RESULTS AND DISCUSSION were used for estimating density. Counts started at sunrise and finished no more than 3 We recorded Southern Antpipits in nine local- h later. At each point we registered all individ- ities, two in Bolivia and seven in Argentina uals seen or heard for 10 min during a single (Table 1). All observations, except two, point count. Simultaneously with point counts occurred between October and January, dur- we recorded vocalizations using a unidi- ing the spring and summer wet season, which

629 ALVAREZ & BLENDINGER is the main reproductive season of most bird In Caiza (Bolivia, Table 1), located in the species in the region. Because of its cryptic eastern slopes of the Aguaragüe range, we behavior and shyness, most detections of the registered one Southern Antpipit in evergreen Southern Antpipit were done by sound. The degraded forest near a creek during a brief lack of records during winter months may be visit to this site. In Argentina, we captured due to migratory movements during the non- and photographed an individual in the locality breeding season (presumably towards the of Abra Grande (Table 1). This site was one Chiquitanía in eastern Bolivia), or to a lower of the few remnant fragments of the premon- detection because of less frequent vocaliza- tane forest in lowland areas, which largely tion in this season. have been transformed to agriculture lands The record in Yumao (Bolivia) corre- (Blendinger et al. in press b). Three other indi- sponds to the northern distribution limit of viduals were tape recorded in Alto Verde the premontane forest of the Austral Yungas; (Table 1), which represented our southern- here we mist-netted four individuals. Those most records of the species. All of them were and at least two other individuals recorded found in evergreen forest growing on the bot- occurred in the dense understory on the tom of shallow gorges. The remaining five lower end of the slopes next to the dry bed of sites where we recorded the Southern Ant- a small creek. In the northern sector of the pipit were located in the Tartagal mountain premontane forest, the bird diversity is influ- range, where this species was frequently enced by the dry forests located towards the observed in the understory and at ground north and northeast, such as Chiquitano for- level of mature forest and old second-growth ests where the presence of the Southern Ant- forest, mostly close to medium-sized creeks. pipit is known. The closest published record All individuals in this area were recorded of the species in Bolivia is in Tejerías (18º28’S, between October and December 2004, except 63º31’W), 80 km north in a semi-deciduous one that was observed on a trail along mature forest with clear Chiquitano affinities (Rivero forest with little human intervention in et al. 2004). Several other bird species frequent August 2004 (Table 1). in lowland forest or dry forests [such as the Black-bellied Antwren (Formicivora melano- Habitat preferences and population density. In the gaster), Bolivian Slaty-Antshrike (Thamnophilus Tartagal mountain range, we censused six sticturus), Fawn-breasted Wren (Thryothorus sites (180 point counts in total) during winter guarayanus) and Flavescent Warbler (Basileu- (from May to August) and five sites (150 terus flaveolus)] were also recorded in Yumao, counts) during spring (October and Novem- but were absent or only occasionally seen in ber). We recorded 11 individuals during southern areas of the premontane forest. spring in four of these sites, whereas none Although species composition of eastern pre- were recorded during winter. The estimated montane forest assemblages are influenced by density for spring for the study area was 0.09 the Chaco along most of its latitudinal range ± 0.33 (mean ± SD) individuals ha-1. Most (Blendinger & Alvarez in prep., see also records (73%) corresponded to points located Fjeldså & Mayer 1996, Herzog & Kessler within 100 m of medium-sized creeks (i.e., 2002), several lowland species seems to con- located in 100 to 1000 ha watersheds). These tact with the premontane forest only in its observations, along with several occasional northern sector (e.g., Yumao), from where records during non-systematic sampling sug- they could expand to the south along pre- gest that the Southern Antpipit occurs in the montane forests. region mainly in the lower part of humid

630 SHORT COMMUNICATIONS gorges associated with medium-sized creeks. the 1960s and 1970s, Olrog and his collabora- In this habitat, the estimated density for the tors sampled birds using mist nets for collec- Southern Antpipit was 0.63 ± 0.64 individuals tion and/or banding purposes. However, no ha-1. additional specimens of Southern Antpipit The premontane forest in the study area is were captured during that time period. Fur- geographically continuous along the Tartagal thermore, the species is not included for and Alto Río Seco mountain ranges, extend- northwestern Argentina in Olrog’s bird guide ing towards the north to the border with (Olrog 1984). The site where Olrog collected Bolivia and to the south up to the northern that specimen belongs to the same mountain margin of the Bermejo river (23°45’S). This range (Tartagal and Alto Río Seco) where we region represents the largest continuous for- obtained most of our records and where other est remnant of the premontane forest of the researchers also recently reported observa- Austral Yungas, with an area of about 430,000 tions of the Southern Antpipit (M. Pearman ha. According to observations conducted pers. com., Coconier in press). As birds in this along a 2-km point count transect during mountain range are being surveyed since four October in the locality of Campo Largo, we decades, the number of new records supports presume that the territories were distributed the idea that the species is expanding to the linearly along the rivers. Based on Landsat south more than it became recorded more image analysis, we estimated 950 linear km of often as consequence of thorough researches. medium-sized creeks preferred by the South- According to the possible expansion of the ern Antpipit for the surveyed area, comprised distribution range of this species towards the between 520 and 1100 m elevation. When south, it is possible that it might be more considering a 100-m buffer to both sides, we widely distributed in northwestern Argentina. estimated that the preferred habitat available Besides our southernmost record in Abra for the Southern Antpipit amounts to 19,800 Grande, another sighting has been reported ha in Argentina. recently for Ledesma (23º46’S, 64º48’W), Tartagal and Alto Río Seco mountain Department of Ledesma in the province of ranges represent the southern distributional Jujuy, in February 2006 (L. O. Rivera pers. limit in the Austral Yungas of several other com.). bird species, such as Military Macaw (Ara mili- As previously mentioned, the scarcity of taris), Lineated Woodpecker (Dryocopus linea- records between April and September sug- tus), White-necked Trush (Turdus albicollis), gests that Southern Antpipits present partial Purplish Jay (Cyanocorax cyanomelas) and Black- migratory behavior in the southern end of goggled Tanager (Trichothraupis melanops). their distribution. The species is regarded as These species are common north of the Ber- resident in most of its range. However, a mejo river but are occasional or absent migratory behavior for southernmost popula- towards the south of this river. In contrast, tions was reported during winter for many available evidence suggests that the distribu- bird species in the Austral Yungas (e.g., tion of the Southern Antpipit is expanding Capllonch 1997, Capllonch & Lobo 2005). towards the south along the premontane for- Flores et al. (2001) consider this species as res- est of the Austral Yungas. The first specimen ident in the Chiquitano forest in eastern of Southern Antpipit collected for this region Bolivia, although it was more abundant during was a male captured in April 1979, 6 km west the wet season. The high density observed in of Piquirenda (Olrog 1979). During several October in Tartagal mountain range might study trips to these mountain ranges during correspond to transient individuals during

631 ALVAREZ & BLENDINGER migration towards the south. However, the REFERENCES scarcity of records farther south does not support this prediction. Furthermore, birds Blendinger, P. G., M. E. Alvarez, S. E. Pacheco, & were regularly spaced and responded aggres- L. Cristóbal in press a. Caracterización ambien- sively to play back, suggesting that they might tal de la Unidad de Gestión Acambuco de Pan have already established nesting territories. American Energy. In Cocconier, E. (ed.). Las aves silvestres de Acambuco, provincia de Salta, Although the individuals we captured did not Argentina. Inventario ornitológico de un AICA show evidence of reproductive activity such prioritaria de la Selva Pedemontana. Temas de as a cloacal protrusion or brood patch, birds Naturaleza y Conservación 6, Aves Argen- in breeding condition were recorded between tinas–Asociación Ornitológica del Plata, Bue- October and December in Bolivia and north- nos Aires, Argentina. eastern Argentina (Fitzpatrick 2004). Blendinger, P. G., L. O. Rivera, M. E. Alvarez, G. We provide novel distribution data for the Nicolossi, & N. Politi in press b. Selección de Southern Antpipit for the Austral Yungas áreas prioritarias para la conservación de aves (Departments of Santa Cruz and Tarija in en la Selva Pedemontana de Bolivia y Argen- Bolivia, and in Salta Province in Argentina), tina. In Brown, A. D., P. G. Blendinger, T. which suggest a recent expansion of this spe- Lomáscolo, & P. García-Bes (eds.). Ecología, historia natural y conservación de la Selva cies range towards the south. Although Pedemontana de las Yungas Australes. Edi- Southern Antpipits seem to be tolerant to ciones del Subtrópico, Tucumán, Argentina. forest disturbances (Hernandes Volpato Brown, A. D., H. R. Grau, L. R. Malizia, & A. 2003), their persistence in the region might be Grau. 2001. Argentina. Pp. 623–659 in Kap- threatened. This species has a marked habitat pelle, M., & A. D. Brown (eds.). Bosques nubla- preference in Austral Yungas, where it occu- dos del Neotrópico. Instituto Nacional de pies almost exclusively the premontane forest, Biodiversidad, San José de Costa Rica, Costa a seriously threatened ecosystem which Rica. undergoes a very high transformation rate. Brown, A. D., P. G. Blendinger, T. Lomáscolo, & P. García-Bes in press. Ecología, historia natural y ACKNOWLEDGMENTS conservación de la Selva Pedemontana de las Yungas Australes. Ediciones del Subtrópico, Tucumán, Argentina. Many of our field trips were part of conserva- Cabrera, A. L. 1976. Regiones fitogeográficas de la tion projects of the premonante forest funded República Argentina. Pp. 1–85 in Enciclopedia by American Bird Conservancy, US Fish & de agricultura, jardinería y fruticultura. Tomo 2. Wildlife Service, Fundación ProYungas and Editorial ACME, Buenos Aires, Argentina. Pan American Energy. We thank Luis Rivera, Capllonch, P. 1997. La avifauna de los bosques de Natalia Politi y Walter Villafañe for their help transición del noroeste de Argentina. Tesis in the field, Luis Rivera for sharing novel Doc., Univ. Nacional de Tucumán, Tucumán, records for this species, and Silvia Pacheco Argentina. who did the spatial analysis of Landsat Capllonch, P., & R. Lobo. 2005. Contribución al Images. Sebastian Herzog and two anony- conocimiento de la migración de tres especies de Elaenia de Argentina. Ornitol. Neotrop. 16: mous reviewers made valuable comments on 145–161. an earlier draft of this paper. We are also Coconier, E. G. in press. Las aves silvestres de indebted to Mercedes Rougès who kindly Acambuco, provincia de Salta, Argentina. translated the Spanish version. Pan American Inventario ornitológico de un AICA prioritaria Energy provided the digital elevation model de la Selva Pedemontana. Temas de Naturaleza used for watershed classification. y Conservación 6, Aves –Asociación

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Ornitológica del Plata, Buenos Aires, Argen- Mazar Barnett, J., & M. Pearman. 2001. Lista tina. comentada de las aves argentinas. Lynx Edi- Fitzpatrick, J. W. 2004. Family Tyrannidae (Tyrant- cions, Barcelona, Spain. Flycatchers). Pp. 170–462 in del Hoyo, J., A. Narosky, T., & D. Yzurieta. 1987. Guía para la iden- Elliott, & D. A. Christie (eds.). Handbook of tificación de las aves de Argentina y Uruguay. the birds of the world. Volume 9: Cotingas to Vásquez Mazzini Editores, Buenos Aires, pipits and wagtails. Lynx Edicions, Barcelona, Argentina. Spain. Narosky, T., & D. Yzurieta. 2003. Guía para la iden- Fjeldså, J., & S. Mayer. 1996. Recent ornithological tificación de las aves de Argentina y Uruguay. surveys in the Valles region, southern Bolivia, Edición de Oro, Vásquez Mazzini Editores, and the possible role of Valles for the evolution Buenos Aires, Argentina. of the Andean avifauna. Technical Report 1, Navarro, G., & M. Maldonado. 2002. Geografía Centre for Research on Cultural and Biological ecológica de Bolivia: vegetación y ambientes Diversity of Andean Rainforests, Rønde, Den- acuáticos. Centro de Ecología Simón I. Patiño, mark. Cochabamba, Bolivia. Flores, B., D. I. Rumiz, & G. Cox. 2001. Avifauna Olrog, C. C. 1979. Notas ornitológicas del noroeste del bosque semideciduo Chiquitano (Santa argentino (Aves Passeriformes). Neotropica 25: Cruz, Bolivia) antes y después de aprove- 125–126. chamiento forestal selectivo. Ararajuba 9: 21– Olrog, C. C. 1984. Las aves argentinas: una nueva 31. guía de campo. Administración de Parques Hennessey, A. B., S. K. Herzog, & F. Sagot. 2003. Nacionales, Buenos Aires, Argentina. Lista anotada de las aves de Bolivia. 5ta ed. Aso- Prado, D. E. 2000. Seasonally dry forests of tropical ciación Armonía/Birdlife Internacional, Santa South America: from forgotten ecosystems to a Cruz de la Sierra, Bolivia. new phytogeographic unit. Edinb. J. Bot. 57: Hernandes Volpato, G. 2003. Caracterização de 437–461. microhabitat de Passeriformes de solo em um Rivero, K., D. Rumiz, J. C. Catari, H. Azurduy, O. fragmento de floresta atlântica no norte do Maillard, L. Acosta, M. A. Aponte, K. Osinaga, estado do Paraná, sul do Brasil. Dissertação de G. Soto, H. Saavedra, J. L. Aramayo, & L. Cés- Mestrado, Univ. Estadual de Londrina, Lond- pedes. 2004. Diagnóstico biológico preliminar y rina, Paraná, Brasil. prioridades de investigación en el Área Prote- Herzog, S. K., & M. Kessler. 2002. Biogeography gida Municipal Parabanó. Rev. Bol. Ecol. Con- and composition of dry forest bird communi- serv. Amb. 15: 63–92. ties in Bolivia. J. Ornithol. 143: 171–204. Ridgely, R. S., & E. G. Tudor. 1994. The birds of Ibisch, P. L., S. Beck., B. Gerkmann, & A. Car- South America: the suboscines . retero. 2003. Ecorregiones y ecosistemas. Pp. Univ. of Texas Press, Austin, Texas. 44–84 in Ibish, P. L., & G. Mérida (eds.). Biodi- versidad: la riqueza de Bolivia. Editorial FAN, Santa Cruz de la Sierra, Bolivia. Accepted 23 August 2007.

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