Bioacoustics characterization and habitat use of glass frogs in El Salvador

Bioacoustics characterization and habitat use of glass frogs in El Salvador




Amphibians, Central America, Centrolenidae, conservation, citizen science, distribution


Introduction: Glass frogs occur from Mexico to South America, and, their taxonomy and distribution are currently debated. In El Salvador, the only species is thought to be Hyalinobatrachium fleischmanni, but it may instead be Hyalinobatrachium viridissimum. In any case, the species is scarcely recorded and understudied. Objective: To estimate the species distribution in the Río Lempa basin, and to compare its call with available records. Methods: We used local volunteers to sample 53 sites in Cabañas and Morazán, El Salvador, during the rainy season (September to November); these were visited once in 2019 and once in 2020. Volunteers counted individuals along transects from 6 to 8 pm and recorded some calls with cell phones. Results: We counted 361 individuals, added 53 new localities (mainly deciduous broad-leaved forest and agricultural systems). Abundance was more related with elevation and forest cover, than with river characteristics. Our evaluation of 32 calls found differences in the peak frequency between these glass frog populations and those of H. fleischmanni and H. viridissimum comb. nov. Conclusion: Salvadorian glass frogs are more widespread than previously recorded, their distribution is more related with elevation and forest than with rivers types, and their taxonomic status remains unsolved.


Alford, R. A., Dixon, P. M., & Pechmann, J. H. (2001). Global amphibian population declines. Nature, 412(6846), 499-500.

Antúnez-Fonseca, C., Juarez-Peña, C., Sosa-Bartuano, Á., Alvarado-Larios, R., Sánchez-Trejo, L., & Vega-Rodriguez, H. (2021). First Records in El Salvador and New Distribution Records in Honduras for Eleutherodactylus planirostris Cope, 1862 (Anura, Eleutherodactylidae), with Comments on its Dispersal and Natural History. Caribbean Journal of Science, 51(1), 37-43.

Argueta, J. G., Chica, E. A., Argueta, S. R., Argueta, J. P., Chica, M., Hernández, M. S., Cruz, J. H., Pérez, V., Pocasangre-Orellana, X., Girón, L., & Álvarez, F. S. (2020). A community-based survey of mammals in the Río Sapo basin, El Salvador. UNED Research Journal, 12(2), e3015-e3015.

Callaghan, C. T., Roberts, J. D., Poore, A. G., Alford, R. A., Cogger, H., & Rowley, J. J. (2020). Citizen science data accurately predicts expert-derived species richness at a continental scale when sampling thresholds are met. Biodiversity and Conservation, 29(4), 1323-1337.

Clark, M. L., Aide, T. M., & Riner, G. (2012). Land change for all municipalities in Latin America and the Caribbean assessed from 250-m MODIS imagery (2001–2010). Remote Sensing of Environment, 126, 84-103.

Collins, J. P., & Storfer, A. (2003). Global amphibian declines: sorting the hypotheses. Diversity and distributions, 9(2), 89-98.

Crespin, S. J., & Simonetti, J. A. (2015). Predicting ecosystem collapse: spatial factors that influence risks to tropical ecosystems. Austral Ecology, 40(4), 492-501.

Di Rienzo, J., Casanoves, F., Balzarini, M., Gonzalez, L., Tablada, M., & Robledo, C. (2011). InfoStat versión 2011.

Dull, R. A. (2008). Unpacking El Salvador's ecological predicament: Theoretical templates and “long-view” ecologies. Global Environmental Change, 18(2), 319-329.

Felger, J., Enssle, J., Mendez, D., & Speare, R. (2007). Chytridiomycosis in El Salvador. Salamandra, 43(2), 122-127.

Fritz, S., See, L., Carlson, T., Haklay, M. M., Oliver, J. L., Fraisl, D., Monardini, R., Brocklehurst, M., Shanley, L.A., Shade, S., When, U., Abrate, T., Anstee, J., Arnold, S., Billot, M., Campbell, J., Espey, J., Gold, M., Hager, G., He,S… West, S. (2019). Citizen science and the United Nations sustainable development goals. Nature Sustainability, 2(10), 922-930.

Frost, D. (2022). Amphibian Species of the World: an Online Reference. Version 6.1. American Museum of Natural History

Greenbaum, E. (2004). A new species of Bolitoglossa (Amphibia: Caudata: Plethodontidae) from montane forests in Guatemala and El Salvador. Journal of Herpetology, 38(3), 411-421.

Greenbaum, E., & Komar, O. (2005). Threat assessment and conservation prioritization of the herpetofauna of El Salvador. Biodiversity and Conservation, 14(10), 2377-2395.

Hansen, M. C., Potapov, P. V., Moore, R., Hancher, M., Turubanova, S. A., Tyukavina, A., Thau, D., Stehman, S. V., Goetz, S.J., Loveland, T.R., Kommareddy, A., Egorov, A., Chini, L., Justice, C.O., & Townshend, J.R.G. (2013). High-resolution global maps of 21st-century forest cover change. Science, 342(6160), 850-853.

Hecht, S. B., & Saatchi, S. S. (2007). Globalization and forest resurgence: changes in forest cover in El Salvador. Bioscience, 57(8), 663-672.

Henríquez, V., & Greenbaum, E. (2014). Geographic distribution: Hyalinobatrachium fleischmanni (Fleischmann’s Glass Frog). Herpetological Review, 45, 87.

Herrador, D., Boada, M., Varga, D., & Mendizábal E. (2011). Tropical forest recovery and socio-economic change in El Salvador: An opportunity for the introduction of new approaches to biodiversity protection. Applied Geography, 31(1), 259-268.

Herrera, N., Henríquez, V., & Greenbaum, E. (2007). New country and department records for amphibians and reptiles from El Salvador. Herpetological Review, 38(2), 222-225.

K. Lisa Yang Center for Conservation Bioacoustics. (2022). Raven Pro: Interactive Sound Analysis Software (Version 1.6.1)

Köhler, G., Veselý, M., & Greenbaum, E. (2006). The amphibians and reptiles of El Salvador. Krieger Publishing Company.

Köehler, J., Jansen, M., Rodriguez, A., Kok, P. J., Toledo, L. F., Emmrich, M., Glaw, F., Haddad, C., Rödel, M-O., & Vences, M. (2017). The use of bioacoustics in anuran taxonomy: theory, terminology, methods and recommendations for best practice. Zootaxa, 4251(1), 1-124.

Kosmala, M., Wiggins, A., Swanson, A., & Simmons, B. (2016). Assessing data quality in citizen science. Frontiers in Ecology and the Environment, 14(10), 551-560.

Mendoza, A. M., Bolívar-García, W., Vázquez-Domínguez, E., Ibáñez, R., & Parra, G. (2019). The role of Central American barriers in shaping the evolutionary history of the northernmost glassfrog, Hyalinobatrachium fleischmanni (Anura: Centrolenidae). PeerJ, 7, e6115.

Mendoza-Henao, A. M., Arias, E., Townsend, J. H., & Parra-Olea, G. (2020). Phylogeny-based species delimitation and integrative taxonomic revision of the Hyalinobatrachium fleischmanni species complex, with resurrection of H. viridissimum (Taylor, 1942). Systematics and Biodiversity, 18(5), 464-484.

Ministerio de Medio Ambiente y Recursos Naturales (MARN). (2015). Listado oficial de vida silvestre amenazada o en peligro de extición.

Ministerio de Medio Ambiente y Recursos Naturales (MARN) (2018). Inventario Nacional Forestal de El Salvador.

Ministerio de Medio Ambiente y Recursos Naturales. (10 de enero, 2022). Sistema de Información Hídrica - SIHI.

Morales-Rivas, A., Álvarez, F. S., Pocasangre-Orellana, X., Girón, L., Guerra, G. N., Martínez, R., Domínguez, J.P., Leibl, F., & Heibl, C. (2020). Big cats are still walking in El Salvador: First photographic records of Puma concolor (Linnaeus, 1771) and an overview of historical records in the country. Check List, 16(2), 563-570.

Redo, D. J., Grau, H. R., Aide, T. M., & Clark, M. L. (2012). Asymmetric forest transition driven by the interaction of socioeconomic development and environmental heterogeneity in Central America. Proceedings of the National Academy of Sciences, 109(23), 8839-8844.

Rodriguez, A., Dugo-Cota, A., Montero-Mendieta, S., Gonzalez-Voyer, A., Bosch, R. A., Vences, M., & Vila, C. (2017). Cryptic within cryptic: genetics, morphometrics, and bioacoustics delimitate a new species of Eleutherodactylus (Anura: Eleutherodactylidae) from Eastern Cuba. Zootaxa, 4221(5), 501-522.

Rowley, J. J., Callaghan, C. T., Cutajar, T., Portway, C., Potter, K., Mahony, S., Trembath, D.F., Flemons, P., & Woods, A. (2019). FrogID: Citizen scientists provide validated biodiversity data on frogs of Australia. Herpetological Conservation and Biology, 14(1), 155-170.

Segura, J., Aguirre, C., Pineda, R., & Pineda, L. (2018). Ampliación de la distribución geográfica de la ranita de vidrio Hyalinobatrachium fleischmanni (Anura: Centrolenidae) en El Salvador. Acta Zoológica Mexicana, 34, 1-4.

Stuart, S. N., Chanson, J. S., Cox, N. A., Young, B. E., Rodrigues, A. S., Fischman, D. L., & Waller, R. W. (2004). Status and trends of amphibian declines and extinctions worldwide. Science, 306(5702), 1783-1786.

Townsend, J. (2014). Characterizing the Chortís block biogeographic province: geological, physiographic, and ecological associations and herpetofaunal diversity. Mesoamerican Herpetology, 1(2), 204-252.

UNEP-WCMC. (2019). Protected Area Profile for El Salvador from the World Database of Protected Areas. Retrieved from

Vargas-Masís, R. (14 diciembre, 2019). Mochuelo enano. BioSonidos.

Ward, M., Saura, S., Williams, B., Ramírez-Delgado, J. P., Arafeh-Dalmau, N., Allan, J. R., Venter, O., Dubois, G., & Watson, J. E. (2020). Just ten percent of the global terrestrial protected area network is structurally connected via intact land. Nature Communications, 11(1), 1-10.

Young, B. E., Lips, K. R., Reaser, J. K., Ibáñez, R., Salas, A. W., Cedeño, J. R., Coloma, L.A., Ron, S., La Marca, E., Meyer, J. R. Muñoz, A., Bolaños, F., Chaves, G., & Romo, D. (2001). Population declines and priorities for amphibian conservation in Latin America. Conservation Biology, 15(5), 1213-1223.

Zamudio-Torres, T.V., Fuentes-de-la-Rosa, D. L., & Ordoñez-Flores, S. (2020). La Colección de sonidos de anuros del Museo de Zoología "Alfonso L. Herrera" de la Facultad de Ciencias. Revista Latinoamericana de Herpetología, 3(1), 132-140.



How to Cite

Álvarez Calderón, F. S., Henríquez, V., Pocasangre-Orellana, X., Argueta Rivera, J. G., & Chica Argueta, E. A. (2022). Bioacoustics characterization and habitat use of glass frogs in El Salvador . UNED Research Journal, 14(2), e4008.