This species is distributed along the lower Andean versant in the upper Río Huallaga drainage, regions of San Martín and Loreto, Peru. It is present at approximately 500–900 m asl. There are subpopulations resembling this species from the north-eastern versant of Peru, but they are not included in this account until their taxonomic status can be more conclusively verified (Lötters et al. 2002). There were also some subpopulations from adjacent Ecuador that were reported to resemble this species in the 2004 assessment, however they actually belong to an undescribed species (S. Lötters pers. comm. February 2018). Its extent of occurrence (EOO) is 9,779 km2.
Habitat and Ecology
This diurnal, terrestrial species lives on or close to the ground in lowland and premontane tropical forest. Individuals are found on banks of steep streams with limited vegetation (J. Brown pers. comm. April 2017). A male and female were found in axillary amplexus during August (Lötters et al. 2002). Two to three weeks later, 600 eggs were deposited in water and six days after that tadpoles hatched and fed on algae (Lötters et al. 2002). It is not known how adaptable the species is to habitat modification. They have also been observed in June and July in north-central Peru in amplexus for a period between 18–46 days (J. Brown pers. comm. April 2017).
This species has experienced dramatic declines in the past, likely to be due to chytridiomycosis. In the 1980s, this species was abundant near montane rivers in eastern San Martín, as 20–40 individuals could be found in a single day at a single locality (R. Schulte and W.E. Duellman pers. comm. in Lötters et al. 2005). During 2004-2007, surveys in San Martín found about 50 individuals over more than 300 person-days (von May et al. 2008). Similar surveys in San Martín detected 16 individuals over 3 person-days during 2007, and again in 2008 (von May et al. 2008). Since 2008, individuals within these subpopulations have continued to be observed (J. Brown pers. comm. April 2017). However, out of 72 transects surveyed during a two month period (May-July), no juveniles were recorded (J. Brown pers. comm. April 2017). Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
The chytrid fungus, Batrachochytrium dendrobatidis, was confirmed in this species in the Cainarachi Valley in 2003 (Lötters et al. 2005), and post-infection subpopulations appear to be threatened by habitat destruction through conversion to agricultural land. Pollution, increased algae growth and climate change, implicated in Atelopus declines (La Marca et al. 2005), are also threats to this species (Lötters et al. 2005, Lötters 2007).
The species occurs in Parque Nacional Cordillera Azul. It is listed as Endangered (EN) in Peru and has legal protection provided by the Categorization in Endangered Species of Wild Fauna (Decreto Supremo Nº004-2014-MINAGRI), which bans all hunting, capture, possession, transport or export of the species for commercial purposes. A captive-breeding program for this species has been established, and there is ongoing research investigating the biology of a subpopulation of this species that has been infected with chytridiomycosis by the Instituto de Investigación Biológica de las Cordilleras Orientales.
Given that chytrid has been found in this species, populations should be monitored closely. Additional surveys need to be carried out to verify its full distribution and determine population density.
Red List Status
Critically Endangered (CR)
Listed as Vulnerable because its extent of occurrence (EOO) is 9,779 km2, it occurs in fewer than 10 threat-defined locations, and there is continuing decline in the extent and quality of its habitat.
This species was removed from the synonymy of Atelpus spumarius by Lötters et al. (2002).
IUCN SSC Amphibian Specialist Group 2018. Atelopus pulcher. The IUCN Red List of Threatened Species 2018: e.T54544A3016090. http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T54544A3016090.en .Downloaded on 21 February 2019