Laboratorio de Ecología y Comportamiento Animal, Instituto de Ecología Genética y Evolución de Buenos Aires (CONICET), Facultad de Cs. Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes s/n, CABA 1428, Argentina | Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina | EDGE Fellowhip Programme, Zoological Society of London, Reagents Park, London, UK
Laura Fasola
Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina | CONICET–Dirección Regional Patagonia Norte (APN), Vicealmirante O’connor 1188, S.C. de Bariloche 8400, Argentina
Juan M. Klavins
Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina
Carolina Facchinetti
1 Laboratorio de Ecología y Comportamiento Animal, Instituto de Ecología Genética y Evolución de Buenos Aires (CONICET), Facultad de Cs. Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes s/n, CABA 1428, Argentina
María Emilia Giusti
Laboratorio de Ecología y Comportamiento Animal, Instituto de Ecología Genética y Evolución de Buenos Aires (CONICET), Facultad de Cs. Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes s/n, CABA 1428, Argentina | Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina
Florencia Ayala
Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina
Estefanía P. Micheltorena
Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina
Julio L. Lancelotti
Programa Patagonia, Departamento de Conservación, Aves Argentinas/AOP, Matheu 1246, CABA 1249, Argentina | Lab.Ecofluvial, IPEEC-CENPAT (CONICET), Blv. Brown 2915, Puerto Madryn 9120, Argentina
Bettina Mahler
Laboratorio de Ecología y Comportamiento Animal, Instituto de Ecología Genética y Evolución de Buenos Aires (CONICET), Facultad de Cs. Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes s/n, CABA 1428, Argentina
Juan Carlos Reboreda
Laboratorio de Ecología y Comportamiento Animal, Instituto de Ecología Genética y Evolución de Buenos Aires (CONICET), Facultad de Cs. Exactas y Naturales, Universidad de Buenos Aires, Int. Güiraldes s/n, CABA 1428, Argentina
conservation Hooded Grebe molt molting migration natural history Patagonia plumage Podiceps gallardoi
How to Cite
Roesler, Ignacio, Laura Fasola, Juan M. Klavins, Carolina Facchinetti, María Emilia Giusti, Florencia Ayala, Estefanía P. Micheltorena, Julio L. Lancelotti, Bettina Mahler, and Juan Carlos Reboreda. 2025. “Plumage Maturation, Molt, and Morphology of the Critically Endangered Hooded Grebe (Podiceps Gallardoi)”. El Hornero 40 (1): 51-59. https://doi.org/10.56178/eh.v40i1.1505.
The understanding of morphological and behavioral aspects of bird species can guide appropriate management actions for their conservation. Grebes (Podicipedidae) are peculiar in their molting strategy, since body feathers are continuously replaced during the whole year. Available information about natural history of Neotropical grebes is scattered. The Hooded Grebe (Podiceps gallardoi) is a critically endangered species with a global population of less than 800 individuals that inhabits the remote highlands plateaus of Austral Patagonia. In this work we present information about sexual differences in molting behavior, plumage coloration and morphological characteristics of this species. During seven years we monitored the whole population of Hooded Grebe and collected data from field observations and from collected individuals that had been killed by American mink. Our results show sexual differences in morphology, and in timing of molting, but not in coloration in the UV and visible range. Hooded Grebe’s molting strategy differs from that of other grebes, including closely related species, as it lacks molting migration and does not develop a visibly different alternate winter plumage. Molting strategies and morphological differences between sexes may represent adaptations to variable conditions in extreme environments of southern Patagonia.
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