Animal personality and behavioral syndromes in amphibians: a review of the evidence, experimental approaches, and implications for conservation

Abstract

Animal personality and behavioral syndromes can have profound effects on individual fitness. Consequently, there is growing recognition that knowledge of these phenomena may assist with animal conservation. Here we review evidence for personality and behavioral syndromes in amphibians (the most threatened vertebrate class), critique experimental approaches, and explore whether knowledge in this domain might assist with endangered species management. Despite being a neglected field (research has spanned just 24 species), there is emerging evidence that frogs, toads, salamanders, and newts show personality and behavioral syndromes along three behavioral axes: boldness, exploration, and activity. Among vertebrates, amphibians are unique in having a biphasic lifecycle defined by metamorphosis and obvious transformations in morphology, physiology, and habitat use, characteristics that enable detailed examination of behavioral changes across life stages and ecological contexts. Accordingly, recent work has started to make important contributions to our understanding of the development and proximate causes of personality and behavioral syndromes, with some emerging evidence for ontogenetic stability, genetic control, and state-dependent personality. To date, however, no study has considered the conservation implications of personality for amphibians. Drawing on a conceptual framework and empirical literature for all vertebrates, we argue that there is considerable potential for knowledge of animal personality to improve amphibian conservation programs. We propose a novel paradigm to improve (i) the mating and reproductive success of captive animals by ensuring that breeding pairs are behaviorally compatible and (ii) the post-reintroduction survival and reproductive potential of animals by facilitating the selection of optimal behavioral types for release. Animal personality and behavioral syndromes appear to be widespread in nature. Here, we review animal personality and behavioral syndromes in amphibians, an understudied taxonomic group within the field. We summarize evidence, critique methodological approaches used, and emphasize that the unique behavioral ecology of amphibians makes them a model group for studying the proximate causes and ecological consequences of personality and behavioral syndromes. We also highlight that knowledge of these phenomena may have significant conservation implications for amphibian captive breeding and reintroduction programs.