Population decline of the Jambato Toad Atelopus ignescens (Anura: Bufonidae) in the Andes of Ecuador

The Jambato Toad, Atelopus ignescens, is endemic to montane forests, inter-Andean valleys, and paramos in Ecuador. Although formerly abundant and widely distributed, the species has not been recorded in nature since 1988. To determine its population status, data from intensive surveys in 1999-2001 are compared with those from 1967 and 1981. Presence-absence data from several localities also are reported. Temperature and precipitation between 1891 and 1999 were analyzed to determine whether these correlate with population trends. Atelopus ignescens was abundant in 1967 at Paramo de Guamaní (47 individuals recorded in 120 pers/min) and in 1981 at Paramo del Antisana (up to 0.75 individuals/m²). In the 1999-2001 surveys, A. ignescens was absent despite considerably higher survey efforts. The presence-absence data at several localities also indicate a dramatic decline. Before 1988, A. ignescens was present during 64% of the visits to sites throughout its range. After 1988, A. ignescens was absent at all sites. The results strongly suggest that A. ignescens is extinct. Climatic data show that 1987, the year previous to the last record of A. ignescens, was particularly warm and dry. The reasons for the decline in pristine areas remain unclear, although the available information suggests that a combination of factors such as pathogens and unusual weather conditions may have played an important role.