Research Fellow in Wildlife Health
Wildlife health
Disease ecology
Population ecology
Biodiversity monitoring
Contact details

Institute of Zoology
Zoological Society of London
United Kingdom

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Andrés conducts research on the drivers and consequences of infectious diseases in free-living host populations, in addition to wildlife monitoring and conservation, with an emphasis on amphibians.

In his research, Andrés generally uses observational and manipulative field studies, along with quantitative analytical approaches (e.g., capture-recapture and occupancy models, simulations) to account for the observational uncertainty inherent in field wildlife studies. Andrés is also interested in contributing to a deeper integration of ecological and evolutionary theory, such as life-history theory, into disease ecology. His main study models are amphibians (e.g. Darwin’s frogs, Mountain Chicken frogs, and Barrio’s frogs) and amphibian pathogens (particularly the chytrid fungus, Batrachochytrium dendrobatidis), but he has also collaborated on projects focusing on other taxa, including mammals and marine invertebrates. 

Andrés is particularly interested in bridging the gap between science and conservation practice, especially through the co-production of actionable science and capacity-building in conservation planning and monitoring. In this respect, he continuously collaborates with conservation managers from both the public and private sectors, as well as with other key stakeholders (e.g., private landowners, educators) in amphibian conservation. He is currently the president of the governance committee of the Binational Conservation Strategy for Darwin’s frogs and co-chair of the Communications & Education Working Group of the IUCN SSC Amphibian Specialist Group. 

At ZSL, Andrés also participates in teaching and supervising PhD and MSc research projects. He is the deputy director of the Wild Animal Biology and Wild Animal Health MSc courses that are jointly delivered by ZSL and the Royal Veterinary College. Within these courses, Andrés co-leads a module on Ecosystem Health and Anthropogenic Drivers of Disease Emergence.

If you are interested in collaborating or conducting a research project (master's or doctoral) please get in touch.

Andres Valenzuela-Sánchez - fieldwork
Andres Valenzuela-Sánchez - fieldwork

More about our work on amphibians

Professional history

2023-Present - Research Fellow in Wildlife Health, Institute of Zoology, Zoological Society of London
2021-2022 - Honorary research associate, Instituto de Conservación, Biodiversidad y Territorio, Universidad Austral de Chile
2018-2020 - Postdoctoral research associate, Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile
2015-Present - President, Ranita de Darwin NGO (Chile)
2012-2017 - PhD in Conservation Medicine, Universidad Andrés Bello (Chile) and Institute of Zoology, Zoological Society of London (overseas PhD student)
2006-2011 - Bachelor of Veterinary Medicine & Surgery, School of Veterinary Medicine, Universidad Andrés Bello (Chile)


Valenzuela-Sánchez A, Miranda S, Moreno-González R, Gerding J, Catrileo R, Guillemot J, ... & Zapararte MB (2024) Partnerships between private landowners and conservationists to protect one of the most evolutionarily distinct amphibians. Oryx (Early View).

Sentenac H, Valenzuela‐Sánchez A, Haddow‐Brown N, Delgado S, Azat C, & Cunningham AA (2023) Accounting for bias in prevalence estimation: the case of a globally emerging pathogen. Journal of Applied Ecology 69: 2007–2017.

Valenzuela-Sánchez A, Schmidt BR, Azat C, Delgado S, Cunningham AA, Lemaître JF, Gaillard JM, Cayuela H (2023) Variable rate of ageing within species: insights from Darwin’s frogs. Biological Journal of the Linnean Society 138: 68–74

Reinke BA, Cayuela H, Janzen FJ, Lemaître JF, Gaillard JM, Lawing AM, Iverson JB, Christiansen DG, Martínez-Solano I, Sánchez-Montes G, Gutiérrez-Rodríguez J, Rose FL, Nelson N, Keall S, Crivelli AJ, Nazirides T, Grimm-Seyfarth A, Henle K, Mori E, Guiller G, Homan R, Olivier A, Muths E, Hossack BR, Bonnet X, Pilliod DS, Lettink M, Whitaker T, Schmidt BR, Gardner MG, Cheylan M, Poitevin F, Golubović A, Tomović L, Arsovski D, Griffiths RA, Arntzen JW, Baron JP, Le Galliard JF, Tully T, Luiselli L, Capula M, Rugiero L, McCaffery R, Eby LA, Briggs-Gonzalez V, Mazzotti F, Pearson D, Lambert BA, Green DM, Jreidini N, Angelini C, Pyke G, Thirion JM, Joly P, Léna JP, Tucker AD, Limpus C, Priol P, Besnard A, Bernard P, Stanford K, King R, Garwood J, Bosch J, Souza FL, Bertoluci J, Famelli S, Grossenbacher K, Lenzi O, Matthews K, Boitaud S, Olson DH, Jessop TS, Gillespie GR, Clobert J, Richard M, Valenzuela-Sánchez A, Fellers GM, Kleeman PM, Halstead BJ, Grant EHC, Byrne PG, Frétey T, Le Garff B, Levionnois P, Maerz JC, Pichenot J, Olgun K, Üzüm N, Avcı A, Miaud C, Elmberg J, Brown GP, Shine R, Bendik NF, O'Donnell L, Davis CL, Lannoo MJ, Stiles RM, Cox RM, Reedy AM, Warner DA, Bonnaire E, Grayson K, Ramos-Targarona R, Baskale E, Muñoz D, Measey J, de Villiers FA, Selman W, Ronget V, Bronikowski AM, Miller DAW (2022) Diverse aging rates in ectothermic tetrapods provide insights for the evolution of aging and longevity. Science 376: 1459–1466.

Valenzuela-Sánchez A, Azat C, Cunningham AA, Delgado S, Bacigalupe LD, Beltrand J, Serrano JM, Sentenac H, Haddow N, Toledo V, Schmidt BR, Cayuela H (2022) Interpopulation differences in male reproductive effort drive the population dynamics of a host exposed to an emerging fungal pathogen. Journal of Animal Ecology 91: 308–319

Valenzuela-Sánchez A, Wilber MQ, Canessa S, Bacigalupe LD, Muths E, Schmidt BR, Cunningham AA, Ozgul A, Johnson PTJ, & Cayuela H (2021) Why disease ecology needs life-history theory: a host perspective. Ecology Letters 24: 876–890.

Perez-Venegas DJ, Valenzuela-Sánchez A, Montalva F, Pavés H, Seguel M, Wilcox C, & Galbán-Malagón C (2021) Towards understanding the effects of oceanic plastic pollution on population growth for a South American fur seal (Arctocephalus australis australis) colony in Chile. Environmental Pollution, 279, 116881.

Azat C, Valenzuela-Sánchez A, Delgado S, Cunningham AA, Alvarado-Rybak M, Bourke J, ... & Ariadne A (2021) A flagship for Austral temperate forest conservation: an action plan for Darwin's frogs brings key stakeholders together. Oryx 55: 356–363.

Cayuela H, Valenzuela-Sánchez A, Teulier L, Martínez-Solano Í, Léna J-P, Merilä J, Muths E, Shine R, Quay L, Denoël M, Clobert J, Schmidt BR (2020) Determinants and consequences of dispersal in vertebrates with complex life cycles: a review of pond-breeding amphibians. The Quarterly Review of Biology 95: 1–36. 

Valenzuela-Sánchez A, Cayuela H, Schmidt BR, Cunningham AA, Soto-Azat C (2019) Slow natal dispersal across a homogeneous landscape suggests the use of mixed movement behaviours during dispersal in the Darwin's frog. Animal Behaviour 150: 77–86.

Valenzuela-Sánchez A, Schmidt BR, Pérez C, Altamirano T, Toledo V, Pérez Í, Teillier S, Cunningham AA, Soto-Azat C (2019) Assessing habitat quality when forest attributes have opposing effects on abundance and detectability: a case study on Darwin’s frogs. Forest Ecology and Management 432: 942–948. 

O'Hanlon SJ, Rieux A, Farrer RA, Rosa GM, Waldman B, Bataille A, Kosch TA, Murray KA, Brankovics B, Fumagalli M, Martin MD, Wales N, Alvarado-Rybak M, Bates KA, Berger L, Böll S, Brookes L, Clare F, Courtois EA, Cunningham AA, Doherty-Bone TM, Ghosh P, Gower DJ, Hintz WE, Höglund J, Jenkinson TS, Lin CF, Laurila A, Loyau A, Martel A, Meurling S, Miaud C, Minting P, Pasmans F, Schmeller DS, Schmidt BR, Shelton JMG, Skerratt LF, Smith F, Soto-Azat C, Spagnoletti M, Tessa G, Toledo LF, Valenzuela-Sánchez A, Verster R, Vörös J, Webb RJ, Wierzbicki C, Wombwell E, Zamudio KR, Aanensen DM, James TY, Gilbert MTP, Weldon C, Bosch J, Balloux F, Garner TWJ, Fisher MC (2018) Recent Asian origin of chytrid fungi causing global amphibian declines. Science 360: 621-627.

Alvarado-Rybak M, Valenzuela-Sánchez A, Cevidanes A, Peñafiel-Ricaurte A, Uribe-Rivera DE, Flores E, Cunningham AA, Soto-Azat C (2018) High prevalence of chigger mite infection in a forest-specialist frog with evidence of parasite-related granulomatous myositis. Parasitology Research 117: 1643–1646.

Valenzuela-Sánchez A, O’Hanlon S, Alvarado-Rybak M, Uribe-Rivera DE, Cunningham AA, Fisher MC, Soto-Azat C (2018) Genomic epidemiology of the emerging pathogen Batrachochytrium dendrobatidis from native and invasive amphibian species in Chile. Transboundary and Emerging Diseases 65: 309–314.

Valenzuela-Sánchez A, Schmidt BR, Uribe-Rivera DE, Costas F, Cunningham AA, Soto-Azat C (2017) Cryptic disease-induced mortality may cause host extinction in an apparently stable host–parasite system. Proceedings of the Royal Society B 284: 20171176.

Valenzuela-Sánchez A, Cunningham AA & Soto-Azat (2015) Geographic body size variation in ectotherms: effects of seasonality on an anuran from the southern temperate forest. Frontiers in Zoology 12:37.

Valenzuela-Sánchez A, Harding G, Cunningham AA, Chirgwin C, Soto-Azat C (2014) Home range and social analyses in a mouth brooding frog: testing the co-existence of paternal care and male territoriality. Journal of Zoology 294:215-223.

Soto-Azat C, Valenzuela-Sánchez A, Collen B, Rowcliffe MC Veloso A & Cunningham AA (2013) The population decline and extinction of Darwin’s frogs. PLoS ONE 8(6):e66957.

View Dr Andrés Valenzuela-Sánchez's full list of publications on ResearchGate.