Estimating demographic parameters like survival or recruitment provides insight into the state and trajectory of populations, but understanding the contexts influencing those parameters, including both biotic and abiotic factors, is particularly important for management and conservation. At a high elevation national park in Central Spain, common toads (Bufo bufo) are apparently taking advantage of the near-extirpation of the midwife toad (Alytes obstetricans), as colonization into new breeding ponds is evident. Within this scenario, we expected demographic parameters of common toad populations to be affected favorably by the putative release from competition. However, we found the population growth rate was negative in 4 of 5 years at the long-standing population; survival probability at the long-standing population and newly-colonised breeding ponds was lower than reported for other toads living at high elevations and the probability of recruitment was inadequate to compensate for the survival rate in maintaining a positive trajectory for either of the breeding ponds. We assessed weather covariates and disease for their contribution to the context that may be limiting the common toad’s successful use of the niche vacated by the midwife toad.
Evidence of a chytrid fungus infection involved in the decline of the common midwife toad (Alytes obstetricans) in protected areas of central Spain.
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Bergmann’s rule in amphibians: combining demographic and ecological parameters to explain body size variation among populations in the common toad (Bufo bufo).
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Life history tradeoffs influence mortality associated with the amphibian pathogen Batrachochytrium dendrobatidis.
Diagnostic assays and sampling protocols for the detection of Batrachochytrium dendrobatidis.
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Bufo boreas Baird and Girard, 1852b, western toad. In:
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LannooM.J. Ed. University of California PressBerkeley.
Effects of amphibian chytrid fungus on individual survival probability in wild boreal toads.
Quantifying the disease transmission function: effects of density on Batrachochytrium dendrobatidis transmission in the mountain yellow-legged frog Rana muscosa.
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Suspension feeding of anuran larvae at low concentrations of Chlorella algae (Amphibia, Anura).