Atelopus ignescens (Cornalia, 1849)
Jambato Toad, Quito Stubfoot Toad
© 2005 Dr. Peter Janzen (1 of 2)
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Colombia, Ecuador
Atelopus ignescens was previously abundant and widely distributed across its range. Studies in the 1960s, 1970s, and early 1980s found large numbers of specimens, while anecdotal evidence from as far back as 1864 also suggests great abundance. Survey evidence suggests that the species was still abundant in some localities between 1984 and 1986, but populations apparently rapidly dropped off around that time. Despite extensive searching for decades, this toad had last been seen in the wild in 1989, so the species was believed to be extinct (Ron et al. 2003). In 2016, a small population was discovered in northern Ecuador (Coloma 2016; Jaynes et al 2022) a remarkable rediscovery and showing how hard it is to declare a species extinct.
Life History, Abundance, Activity, and Special Behaviors
Trends and Threats
Habitat degradation may have contributed, as 27.1% of the paramo and 33.3% of Andean forests have been cleared in Ecuador (Ron et al. 2003). However, this species is able to withstand some degree of habitat degradation. In addition, there is little evidence of human interference in two protected areas where the species was previously found but now is not. Thus habitat degradation is probably not the main cause of this extinction (Ron et al. 2003).
Another possible cause is the presence of introduced predatory fishes, as two exotic species of salmonids have been found in streams and lakes of Ecuador’s highlands. However, this idea is not corroborated by evidence of predation. In addition, salmonids have been found within the range of A. ignescens since the 1950s, long before the toads’ decline. Furthermore, the salmonids are not found throughout the entire range of A. ignescens (Ron et al. 2003).
Another possible factor may be the dramatic increase in mean annual temperature in Ecuador in recent years. Of ninety years of climatic data analyzed in a study by Ron et al., the year 1987 saw the most extreme combination of warm and dry conditions. These conditions may have increased adult toad mortality, reduced reproductive success, or made the toad more vulnerable to attack by weakening immune function (Ron et al. 2003).
Possible reasons for amphibian decline
General habitat alteration and loss
Harlequin frogs (genus Atelopus) are one of the most iconic groups decimated in the amphibian decline crisis. It is difficult to know when a species is truly extinct and to study populations on the brink of extinction due to their population size and endangerment. Standalone reports of Atelopus species rediscoveries (i.e., once missing but found again) have grown substantially over the last decade, but their extent across the imperiled genus and population status’ have remained elusive in most cases. Jaynes et al. (2022) characterized Atelopus rediscoveries to investigate temporal, geographic, and genomic diversity patterns of persisting populations. They estimate that between 18 and 32 species have been rediscovered in the genus since 2002, representing 25-37% of once missing species. Rediscoveries are documented everywhere the genus occurs – spanning 100 m to > 3500 m in elevation, and geographic patterns closely matching known species abundance in each country. Genomic analysis in the geographic epicenter of Atelopus rediscoveries (Ecuador) revealed a pattern of decreased heterozygosity the longer a species was considered missing or extinct, and loss of heterozygosity over time in one species with historical comparisons. This study shows that persistence is widespread in Atelopus, but rediscovery does not equal recovery, and many species are still likely living on the brink of extinction. The Atelopus rediscovery system may serve as an important tool for understanding amphibian population persistence under global change.
Coloma, L. A. (2016). El Jambato negro del páramo, Atelopus ignescens, resucitó. IMCiencia. [link]
Coloma, L. A., Lotters, S. A., and Salas, A. W. (2000). ''Taxonomy of the Atelopus ignescens complex (Anura: Bufonidae): Designation of a neotype of Atelopus ignescens and recognition of Atelopus exiguus.'' Herpetologica, 56(3), 303-324.
Jaynes, K.E., M.I. Páez-Vacas, D. Salazar-Valenzuela, J.M. Guayasamin, A. Terán-Valdez, F.R. Siavichay, S.W. Fitzpatrick, and L.A. Coloma (2022). "Harlequin frog rediscoveries provide insights into species persistence in the face of drastic amphibian declines." Biological Conservation, 276(109784). [link]
La Marca, E., Lötters, S., Puschendorf, R., Ibáñez, R., Rueda-Almonacid, J. V., Schulte, R., Marty, C., Castro, F., Manzanilla-Puppo, J., García-Pérez, J. E., Bolaños, F., Chaves, G., Pounds, J. A., Toral, E., and Young, B. E. (2005). ''Catastrophic population declines and extinctions in neotropical harlequin frogs (Bufonidae: Atelopus).'' Biotropica, 37(2), 190-201.
Ron, S., Duellman, W. A., Coloma, L. A., and Bustamante, M. R. (2003). ''Population decline of the Jambato Toad Atelopus ignescens (Anura: Bufonidae) in the Andes of Ecuador.'' Journal of Herpetology, 37(1), 116-126.
Originally submitted by: Benjamin Fryer (first posted 2004-05-05)
Edited by: Kellie Whittaker, Michelle S. Koo (2022-12-18)
Species Account Citation: AmphibiaWeb 2022 Atelopus ignescens: Jambato Toad <https://amphibiaweb.org/species/55> University of California, Berkeley, CA, USA. Accessed Oct 2, 2023.
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Citation: AmphibiaWeb. 2023. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 2 Oct 2023.
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