A MIGRATORY BOTTLENECK FOR THE WHITE-THROATED HAWK BUTEO ALBIGULA IN THE ANDEAN FOOTHILLS OF CENTRAL CHILE

Authors

  • Tomás Antonio Rivas Fuenzalida Fundación Ñankulafkén https://orcid.org/0000-0003-3040-3583
  • Santiago Castrilli Fundación Ñankulafkén, Reserva Natural El Natri, Ruta P-60, km 42, Contulmo, Chile
  • Enrique Ziehlmann Fundación Ñankulafkén, Reserva Natural El Natri, Ruta P-60, km 42, Contulmo, Chile
  • Katherine Burgos-Andrade Fundación Ñankulafkén, Reserva Natural El Natri, Ruta P-60, km 42, Contulmo, Chile https://orcid.org/0009-0004-4770-6729

DOI:

https://doi.org/10.58843/ornneo.v34i2.1199

Keywords:

Accipitridae, Andean corridor, Austral Temperate Forests, Conservation, Migration counting

Abstract

The White-throated Hawk Buteo albigula is one of the most abundant migratory raptors in the Austral-Neotropical system, but no bottlenecks in its migratory routes are known. Here, we describe the finding of the first migratory bottleneck for this species on the Andean slopes of central Chile. We counted a total of 5,424 White-throated Hawks migrating from south to north from 17 March until 13 April 2023, in Cachapoal, O'Higgins Region, Chile (34° S; 70° W). In addition, we counted 1,314 Variable Hawks Geranoaetus polyosoma and seven Cinereous Harriers Circus cinereus migrating through this site for a total of 6,745 raptors, which represent the largest count of migrant raptors in the Austral-Neotropical system. Both, the passage rate (24.2 hawks/hour) and the total number of White-throated Hawks observed per season, were higher at Cachapoal than at any other previous count site (daily passage rate range = 1.0–7.2 hawks/hour; total hawks per season = 35–294). We estimated that over 84% of the breeding population of White-throated Hawks transit the Cachapoal bottleneck during their autumn migration. Remote tracking technologies and observations at other points of the Andes should help to further examine this proposal. Continuing with the long-term count of White-throated Hawks in this bottleneck will allow us to assess the population trends of this important predator in the southern temperate forests.

References

Bechard, MJ, L Simpson, KL Bildstein & DR Barber (2010) White-throated Hawk (Buteo albigula): the first transequatorial raptor migrant from South America. Second Conference Bird Migration and Global Change: movement ecology and conservation strategies, Algeciras, Spain: 17.

Bildstein, KL (2004) Raptor migration in the Neotropics: Patterns, processes, and consequences. Ornitología Neotropical 15: 83–99.

Bildstein, KL (2006) Migrating raptors of the world: their ecology and conservation. Ithaca, NY USA: Cornell University Press.

Bildstein, KL, CJ Farmer & R Yosef (2009) Raptor population monitoring: examples from migration watchsites in North America. Avocetta 33: 43–51.

BirdLife International (2023) Species factsheet: Buteo albigula. Downloaded from http://datazone.birdlife.org/species/factsheet/white-throated-hawk-buteo-albigula [Accessed: 11 May 2023].

eBird (2023) eBird: An online database of bird distribution and abundance [web application]. eBird, Cornell Lab of Ornithology, Ithaca, New York. Available: http://www.ebird.org. [Accessed 4 May 2023].

Juhant, MA (2010) Austral spring migration counts of raptors in Runta Rasa, Argentina. Ornitología Neotropical 21:263-270.

Juhant, MA & Seipke, SH (2010) Austral autumn migration counts of raptors in Argentinean Patagonia. Hawk Migration Studies 35: 7–10.

Medel, J, KL Bildstein, RP Schlatter & JG Navedo (2018) Discovery of an austral migratory corridor for raptors in South America. Journal of Raptor Research 52: 89–93. https://doi.org/10.3356/JRR-16-110.1

MMA [Ministerio del Medio Ambiente]. 2020. Aprueba y ofi­cializa clasificación de especies según estado de conserva­ción, decimosexto proceso. Decreto Supremo N° 16, 3 de agosto de 2020. Diario Oficial de la República de Chile 42: 1–4.

Olivo, C (2003) Fall migration of the White-tailed Hawk in Central Bolivia. Journal of Raptor Research 37: 63–64.

Pavez, EF (2000) Migratory movements of the White-throated Hawk (Buteo albigula) in Chile. Journal of Raptor Research 34: 143–147.

Pavez, EF (2007) Buteo albigula en vuelo migratorio en Chile central. Boletín Chileno de Ornitología 13: 64.

Pavez, EF (2014) Patrón de movimiento de dos cóndores andinos Vultur gryphus (Aves: Cathartidae) en los Andes centrales de Chile y Argentina. Boletín Chileno de Ornitología 20: 1–12.

Pereyra, R, D Ponzina & David Argumedo (2021) Primer registro de Aguilucho chico (Buteo albigula) para la provincia de Mendoza, Argentina. Nótulas Faunísticas, Segunda Serie. 320: 1–5.

Rivas-Fuenzalida, T & D Martínez-Piña (2020) Primera descripción del plumaje básico II (segundo año) del Aguilucho chico (Buteo albigula). Boletín Nahuelbuta Natural 6: 3.

Rivas-Fuenzalida, T & Y Quispe-Flores (2021) Áreas de escala migratoria y dormidero comunitario del aguilucho chico (Buteo albigula) durante su migración hacia el norte de los Andes. Ornitología Neotropical 32: 170–174. http://dx.doi.org/10.58843/ornneo.v32i2.307

Rivas-Fuenzalida, T, Y Quispe-Flores & C González B (2017) Nuevos antecedentes sobre la ecología migratoria del Aguilucho chico (Buteo albigula). XII Congreso Chileno de Ornitología, Santiago, Chile, 21–23 de noviembre de 2017.

Rivas-Fuenzalida, T, S Castrilli, J Toledo & R Figueroa (2023). White-throated Hawk (Buteo albigula). Version 2.0. In: SM Billerman (ed.) Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. [Accessed 30 November 2022]. https://doi.org/10.2173/bow.whthaw1.02

Runge, CA, TG Martin, HP Possingham, SG Willis& RA Fuller (2014) Conserving mobile species. Frontiers in Ecology and the Environment 12: 395–402. https://doi.org/10.1890/130237

Sympson, L, A Trejo, P Capllonch, V Sympson, V Ojeda, M Gelain, MJ Bechard& K Bildstein (2006) Distribution and migratory status of the White-throated Hawk (Buteo albigula). II Neotropical Raptors Conference, Iguazu, Argentina, 11–14 June 2006.

Thake, MA (1980) Gregarious behaviour among migrating Honey Buzzards (Pernis apivorus). Ibis 122: 500–505. https://doi.org/10.1111/j.1474-919X.1980.tb00905.x

Trejo, A, RA Figueroa & S Alvarado (2006) Forest-specialist raptors of the temperate forests of southern South America: a review. Revista Brasileira de Ornitología 14: 317–330.

Trejo, A, P Capllonch & L Sympson (2007) Migratory status of the White-throated Hawk (Buteo albigula): what do we know up to now? Ornitología Neotropical 18: 11–19.

Vásquez, A & P Allasi (2017). Registros documentados del Aguilucho de garganta blanca (Buteo albigula) al oeste de la cordillera de los Andes en Arequipa y Lambayeque. Boletín de la Unión de Ornitólogos de Perú. 12: 24–26.

Wehrmann, J, F de Boer, R Benjumea, S Cavailès, D Engelen, J Jansen, B Verhelst & WMG Vansteelant (2019) Batumi Raptor Count: autunm raptor migrationcount data from the Batumi bottleneck, Republic of Georgia. ZooKeys 836: 135–157. https://doi.org/10.3897/zookeys.836.29252

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Published

25-01-2024

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