Integrative and objective science is the best link between amphibian decline research and conservation on the ground

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1 Alytes, 2012, 29 (1 4): Integrative and objective science is the best link between amphibian decline research and conservation on the ground Carlos A. Navas a, Catherine R. Bevier b & Ana Carolina Carnaval c a Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão Tr. 14 No. 321, CEP São Paulo, SP, Brazil b Department of Biology, Colby College, Waterville, ME 04901, USA c Department of Biology, The City College of New York, Marshak Science Building #526, 160 Convent Ave, New York, NY 10031, USA; <acarnaval@ccny.cuny.edu>; corresponding author The amphibian decline crisis has prompted an extraordinary proliferation of research in various relevant areas, both in the laboratory and in the field. This high level of activity is essential to inform sound conservation action on the ground, and will be most useful if coordinated through an objective, critical and integrative approach to amphibian decline research. We focus on studies surrounding the amphibian disease chytridiomycosis, and caution scientists to refrain from establishing unsubstantiated dogma about the nature of the relationship between chytrid and population declines. To provide the best possible direction for conservation, investigators should continue to collaborate in studies that integrate across disease, amphibians and the environment, and to pursue novel and transformative research initiatives. Introduction The recent and dramatic global decline of amphibian species is well documented as a human-driven process (Wake & Vredenburg, 2008). Examples include habitat conversion, shifts in average and extreme climatic variables, simplification of communities, and dispersion of novel substances, species and pathogens into once pristine habitats (Collins & Storfer, 2003; Hayes et al., 2010). In some systems, diversity reduction may be obviously attributed to specific sources, such as habitat loss and fragmentation. As an example, fragmentation of the Brazilian Atlantic rainforest led to decreased genetic diversity in local bufonid frogs (Dixo et al., 2009) and to a split between residence and reproductive habitats (Becker et al., 2007). Other scenarios are more complex, but still accessible through scientific research. For instance, correlative evidence shows that ponds near agricultural zones are often contaminated

2 120 ALYTES 29 (1 4) by agrochemicals and that larval malformations are increasingly common in agricultural areas (Hayes et al., 2003; Taylor et al., 2005; Mann et al., 2009). Experimental tests further demonstrate that common agrochemicals cause larval malformation (Fort et al., 1999; Hayes et al., 2006; Relyea, 2009). Assuming that larval malformation has meaningful demographic effects, this thread of premises leads to adequate generalized conservation strategies, such as the reduction or treatment of pollutants, monitoring changes in water quality, and remediation of affected environments. Although seemingly simple, this example results from interdisciplinary research that relies on both correlational evidence and experimental confirmation. A first step generates hypotheses of cause-and-effect relationships based on correlational trends. These hypotheses are later tested through well-designed experiments. Most amphibian population declines are intrinsically multi-factorial, with complex cause-and-effect relationships, where both determinism and contingency play a role (Hayes et al., 2010). As a consequence, using current knowledge to develop generalized strategies for amphibian conservation, albeit necessary, is far from trivial. A most challenging aspect is turning knowledge garnered from scientific research into specific action. A key question emerges: what are the best possible policies for conservation given current available information? Although legitimate, this practical approach differs from that taken by most scientists, who intentionally seek to collect the most accurate possible information that will provide guidance for conservation. As a result of such a careful approach, reputable solutions in science typically require several generations. A complicating issue here is that appropriate recommendations may be context-specific and apply best to a particular taxon or geographical area. When conflating the above, it seems that amphibian conservation needs immediate but flexible recommendations based on sound scientific knowledge that can be adjusted as science progresses. Such recommendations are most useful if they readily apply to multiple cases and situations, even if they are based on partial or fragmented information. However, generalization is risky business. Although appropriate generalizations may lead to the best conservation policies given current data, flawed generalizations can make matters worse, waste time and resources, or ignore key elements. These considerations are particularly important precisely because it has become clear that amphibian declines are context-specific (Wake & Vredenburg, 2008), and the best conservation policies may be restricted in application. Depending on the nature of observed demographic patterns, causes and context may be best addressed within fixed eco-geographic limits (i.e., biome-specific studies) or through systematic approaches (e.g., comparisons across species within a lineage). In the face of the complexity of the subject, we need science to produce, as soon as possible, the most educated generalizations regarding the causes of context-specific amphibian declines. This involves at least two main issues that are foci of this paper: (1) what research approaches should we implement to understand the cause of amphibian declines, and (2) how should science, as a social institution (sensu Lewontin, 2004), address the topic of anuran declines. We claim that integrative, coordinated and interdisciplinary research will hasten useful answers (Wake, 2008; Hayes et al., 2010), and underscore an urgent need for carefully designed experimental studies (e.g., Bancroft et al., 2009; Relyea et al., 2009). We also plead for the most objective interpretation of current data, so that overstatements and factoids lose ground as we make progress in the study of amphibian declines.

3 Navas et al. 121 Research approaches: the need for integration Early studies of amphibian declines focused mostly on single causative agents, largely reflecting the expertise and interest of investigators (e.g., Blaustein et al., 1994; Semlitsch & Bodie, 1998; Fort et al., 1999). This single-variable approach was not only understandable given scientific knowledge at the time, but a simpler investigation route. Such line of action often provides the only possibility to deepen our understanding of a given causal agent, such as chytridiomycosis (see for example: Berger et al., 1998; Longcore et al., 1999). Moreover, it generates a foundation upon which more complex, multi-factorial studies can be built. The intensification of the amphibian population decline debate was nonetheless followed by increased interest to understand some of the synergistic interactions among multiple decline-causing agents (Pounds et al., 2006; Relyea, 2006; Hayes et al., 2010; Reeves et al., 2010). Especially insightful were the early recommendations of Alford & Richards (1999), who pointed out the complex relationships between specific populations under study, their environmental stressors, and inherent immune functions. Yet, complex, synergistic studies often demand substantial resources and research logistics (e.g., to incorporate complexity in field or lab experiments), and expertise. Considering the fact that most investigators have limited timeframes to produce publishable or conclusive results (to justify funded research programs or degrees, for instance), it is not surprising to see, still today, relatively few synergistic investigations about amphibian declines that do not rely on metadata analyses (e.g., Bancroft et al., 2008; Rohr et al., 2008). As a corollary, relatively few research groups have invested in experimental, multi-factorial studies within their study systems (for an example, see Woodhams et al., 2007). Whereas almost every recent publication acknowledges the role of synergism among causal factors in amphibian declines, most studies divert from the theme and focus on one or two main factors. The current context of anuran declines poses a trade-off in the sense that simple studies may be the only and perhaps best way to tackle a poorly known phenomenon (e.g., Voyles et al., 2009), but oversimplification involves risks. Whereas few research laboratories have the resources required to address multiple relevant variables simultaneously, it is crucial to keep in mind that amphibian populations are being affected by whole environment change, rather than shifts in isolated variables. There must be no turning away from integrative studies in current amphibian decline research (Wake, 2008; Blaustein et al., 2009; Hayes et al., 2010), and collaboration among research groups, as well as increased funding of multi-factorial analyses, may be our best shot at arriving at proper recommendations for conservation. The term integrative must be as broadly applied as possible to include not only studies of combined effects of decline-leading agents (e.g., pathogens and environmental change), but also cross-disciplinary investigations within biology (e.g., incorporation of historical processes into demographic studies, or merging of ecological and evolutionary research). These approaches will link scientific knowledge with conservation action on the ground through system-focused studies where generalizations are not the immediate goal. Rather, conservation effectiveness in-situ will rely on a deep understanding of the links between the many local and regional processes, across space and time, that lead to observed population shifts. Only a synthesis across many such integrative and system-based studies will point us the right direction toward proper generalized strategies for amphibian conservation.

4 122 ALYTES 29 (1 4) Consensus practice and objectivity Science, as a process, should be unbiased. Yet, human beings tend to depend on external aid and peer recognition to conduct research, and are influenced by various individual and cultural practices (Kitcher, 1993). It is not surprising, then, that individual scientists tend to emphasize their own views and lines of research, and occasionally overstate the implications of their work. Whereas the diversity of individual views and practices is part of the nature of science, scientific progress is accelerated when individual scientists behave and relate to others in ways that expedite reaching common research goals (Kitcher, 1993). Amphibian declines are occurring worldwide and this constitutes an emergency situation (Wake &Vredenburg, 2008). It is precisely because of this sense of emergency that consensus practice (sensu Kitcher, 1993) and objectivity become paramount. Both are fundamental for effective scientific communication in its most ample meaning that is, to maintain open channels for information exchange with policy makers, fellow scientists, the media and the public. As a first approach to evaluate consensus practice in anuran decline research, we analyzed how authors differ in their views about the causal agent of the declines they study. Consistent points of view would indicate that the field has reached consensus practice. Conversely, lack of consensus would be reflected in open debates, overstatements and different perceptions amongst scientists. One collateral effect of the latter possibility may be a tendency for readers to differentially interpret what is stated in a set of publications, including superficial citing (i.e., citing a study as evidence of what only a fraction of the community accepts as derived from that report). We restricted our analysis to the specific context of amphibian declines and chytridiomycosis, an especially prolific and well-funded research topic. Several unsettled aspects make this topic ideal for our analysis. Convincing evidence suggests that this disease has played a role in the decline of many amphibian populations (e.g., Lips et al., 2006; Rachowicz et al., 2006; Schloegel et al., 2006): when habitat loss is not an obvious problem, chytridiomycosis may very well be an excellent ad hoc hypothesis applicable to unexplained declines. However, hypotheses require support from evidence, and the conceptual expansion from context-specific evidence to global hypotheses needs extreme care. Even so, multiple publications (e.g., Berger et al., 1998; Skerratt et al., 2007) have portrayed the amphibian chytrid as primary cause of amphibian declines globally. Many authors perceive this generalization as a hypothesis, not a fact, especially given the lack of studies of synergistic effects at a global scale (McCallum, 2005) and the correlative links observed between declines and environmental changes (Pounds et al., 2006). Note that a semantic issue permeates this discussion because the meaning of the verb to cause, when used in the absence of any qualifier, can be ambiguous regarding the level of causality. For example, research carried out so far provides solid evidence that Batrachochytrium dendrobatidis infections can kill frogs; no doubt exists about the role of B. dendrobatidis as the proximate cause of frog death in such studies (e.g., Voyles et al., 2009). However, ultimate causes are much more complex as they involve all factors that may make a frog population more vulnerable to infection. Notwithstanding this complexity, authors of relevant reports have used the word cause to indicate that chytridiomycosis does kill individual frogs, independently of the reasons why this happened in a population, at a given time. For the

5 Navas et al. 123 sake of accuracy and clarity, we suggest that scientists stop assuming common understanding when using causality statements. To offer solid ground to this discussion, we searched the ISI Web of Knowledge. In particular, we were concerned about individual variation in the perception of the scope of the chytridiomycosis problem, which could range from a context-specific issue to a global cause of widespread declines. What we present here is a brief annotated survey of publications available as of May 1, We used Batrachochytrium dendrobatidis in a topic search and obtained 261 publications since the original description of B. dendrobatidis (Longcore et al., 1999). We then identified articles that cited B. dendrobatidis in the abstract, excluding three meeting abstracts, being left with 250 publications. The articles were placed into ten different categories, ranging from detailed experiments on B. dendrobatidis itself (e.g., Piotrowski et al., 2004) or on how infection affects tadpole or adult frog behavior (e.g., Venesky et al., 2009), to overarching reviews of the global implications of the disease (e.g., Fisher et al., 2009). We analyzed trends in this broad database and then reviewed the 20 most frequently cited papers in that list (tab. 1), assessing how authors have linked the decline of an amphibian population with the presence of chytrid infection. Our goal was not to judge the quality of the science presented by these papers, but to discuss the variation in the perception of a problem among individual scientists. A large proportion of the 250 articles (40.8 %) corresponds to field reports or specimen surveys of B. dendrobatidis infection or susceptibility to infection in amphibian hosts. Several authors provided ample evidence of variation in species-level and population-level response to chytrid presence (e.g., Retallick et al., 2004; Rachowicz et al., 2006; Murphy et al., 2009). Three articles reported absence of B. dendrobatidis (Pasteris et al., 2006; Garcia et al., 2007; Luger et al., 2008) and Murphy et al. (2009) reported that frogs in the population tested positive, despite lack of mortality. Five of these 102 survey reports outright identified the chytrid as the cause of decline or extinction of at least one population or species (e.g., Mutschmann et al., 2000; Muths et al., 2003; Weldon et al., 2004; Rachowicz et al., 2006; Schloegel et al., 2006). Interestingly, the reports on absence of infection were cited much less frequently in the subsequent amphibian decline literature (2 6 times) relative to the five positive reports (> 20 times). Eight of the 250 papers (3.2 %) identified chytrid as the proximate driver of extinction. However, a strong majority of articles made introductory generalizations about the devastating impact of B. dendrobatidis, tending to extrapolate the importance of B. dendrobatidis to unproven scopes while omitting important issues, such as the roles of other potential causes of decline and unequal influences of infection. Although most authors clarified their viewpoints in other sections of the article, this practice creates a problem that goes beyond the scientific community. Because the introduction is usually the most accessible part of a scientific paper, sweeping generalizations may mislead the educated, non-specialist community, including science divulgators and users of information. Our detailed assessment of the 20 top-cited papers (tab. 1) showed that inconsistencies in data interpretation, and therefore in the ideas accepted as derived from a research project, are, as a matter of fact, not uncommon in amphibian decline research. A more detailed analysis of all 20 papers is beyond the scope of this essay, so we illustrate our point of possible superficial citing using Lips et al. (2006) as an example. This paper presents two seemingly contrasting statements: We present evidence that this emerging infectious disease of amphi-

6 124 ALYTES 29 (1 4) bians was absent, at very low prevalence, or present saprobically in the environment before it abruptly increased in prevalence in many amphibian species and was followed by widespread mortality and local population extirpations (Lips et al., 2006, last paragraph of Introduction section), with Our results demonstrate that the prevalence of B. dendrobatidis increased from zero to high prevalence very rapidly at our site, suggesting that B. dendrobatidis invaded the region, causing an epizootic (which initiates the Discussion section of the same paper). We perceive two different implications in these statements: the first concludes that the chytrid could have been present locally prior to population declines, the latter concludes it was originally absent. Summarizing statements by Lips et al. (2006) actually adhere to the second view, despite the fact that the authors failed to test, or ignored, the falsifying hypotheses discussed in their own Introduction: We report the link between the rapid appearance of a pathogenic chytrid fungus Batrachochytrium dendrobatidis in an amphibian community at El Copé, Panama, and subsequent mass mortality and loss of amphibian biodiversity across eight families of frogs and salamanders (Lips et al., 2006, Abstract). In our view, this article should not be cited as indicating field-based evidence of chytridiomycosis-related declines following pathogen arrival (e.g., Collins & Crump, 2009: 153), as if consensus existed about the initial status of the chytrid population. The careful considerations made in Lips et al. s (2006) introductory remarks are somehow being lost in the process of data interpretation, and being overlooked by those citing the article. Our analysis of the restricted database also evaluated whether the author(s) of each paper explicitly identified the cause of anuran mortality as stemming directly from B. dendrobatidis infection, using terms such as proximate cause or causal link, or if B. dendrobatidis was implicated as one of a number of causes of amphibian population declines. As before, we focused on the Introduction only, though in most cases the evidence and statements presented later clarified the author(s) position. Our literature review indicates that in 40 % of the 20 top-cited chytrid papers, authors link infection with population decline or individual mortality primarily using correlational evidence, which may suggest, but does

7 Navas et al. 125 not prove, causality. In addition, many of these papers do not specifically address evidence for possible alternative causes of declines or synergistic interactions, so the literature is plagued with overstatements or statements of ambiguous interpretation. We recommend avoiding quotes that are not explicit in the level of causality, for example, The global emergence and spread of the pathogenic, virulent, and highly transmissible fungus Batrachochytrium dendrobatidis, resulting in the disease chytridiomycosis, has caused the decline or extinction of up to about 200 species of frogs (Skeratt et al., 2007). A causality statement such as this can lead to the conclusion that the chytrid fungus is the ultimate cause of widespread declines, despite lack of supporting evidence at that level. While re-iterating that our key point is unrelated to the scientific merit of the papers cited here, we point to the need of common ground in communication. As readers and authors, we have interpreted these texts in a given manner ourselves, and our interpretation may reflect neither the communication aim of the authors, nor the interpretation of other readers. Yet, this possibility only reinforces the need of consensus practice and objectivity in doing and communicating science. We found no ambiguity in 60 % of the 20 most frequently cited papers presenting experimental or observational data on B. dendrobatidis itself, or on the response of amphibians to the chytrid presence under laboratory conditions. As an example of what we consider objective language, Nichols et al. (2001) identified a correlation between presence of cutaneous chytridiomycosis and death in two species of Dendrobates, but did not state that the chytrid was the ultimate cause of mortality. Some authors present information to reveal a connection between chytrid presence and onset of chytridiomycosis, but are explicit the scope and context of causality in the interpretation of data (e.g., the mechanism by which cutaneous chytridiomycosis becomes a fatal infection, however, is still unknown, Ouellet et al., 2005). This care helps readers and improves communication in the field. The most commendable positions of course shall be unbiased, but unbiased thinking may be obscured by ambiguous writing. Objectivity, clarity, and precise limits to causality statements should become consensus practice in the anuran decline literature. On a similar note, Ohmer & Bishop (2010) performed a quantitative analysis of the literature on amphibian declines from 1990 to 2009 to determine if there has been a shift toward study of novel stressors, as proposed by Gardner et al. (2007). Indeed, papers on chytridiomycosis were cited significantly more often than papers on other sources of decline, even when the years since publication and impact factor of the journal were treated as covariates. Of the seven identified topics, research on climate, chytridiomycosis and UVB appeared in journals with the highest impact factors (Ohmer &Bishop, 2010). However, there does not appear to be a subject area bias in terms of the proportion of publications on these research topics. Recommendations: Approach to Research Towards consensus practice in B. DENDROBATIDIS research and report The role attributed to B. dendrobatidis as the major driver of anuran declines at a global scale abounds in the amphibian decline literature (e.g., Skerratt et al., 2007; Kilpatrick et

8 126 ALYTES 29 (1 4) al., 2010), despite the fact that other potential causes and synergistic interactions have not been ruled out on a case-by-case basis. Koch s postulates are clearly satisfied in determining that B. dendrobatidis causes chytridiomycosis in amphibians, and the disease can be highly virulent in some populations (Longcore et al., 1999; Nichols et al., 2001). Batrachochytrium dendrobatidis is certainly one potential proximate cause of declines. The processes by which chytridiomycosis develops and kills frogs have been reported from simple laboratory studies (e.g., Nichols et al., 2001; Voyles et al., 2009), but several correlative studies and experimental demonstrations show chytridiomycosis-related outbreaks are highly context dependent (e.g, Kriger & Hero, 2006; Woodhams et al., 2007; Briggs et al., 2010). Some species populations persist with the infection, perhaps serving as carriers of the disease, but clearly do not succumb to a morbid infection (Daszak et al., 2004; Retallick et al., 2004; Longcore et al., 2007). Amphibian population crashes have been documented for many years preceding reports of chytridiomycosis outbreaks, and some of the recently reported declines are not attributed to disease (e.g., Daszak et al., 2005; McCallum, 2005; Puschendorf et al., 2006). The tendency to focus on chytridiomycosis as the major driver of anuran declines at a global scale does not help to speed up conservation goals, and should not be part of consensus practice. Overlooked exceptions and improper generalizations limit scientific progress and obscure promising new research opportunities. Thus, a valuable consensus for the field would be to emphasize context-specific mortality, and limit broad statements about the pervasiveness of chytrid-driven declines to what is supported by evidence. For example, understanding why some species and populations of anurans seem more sensitive to the chytrid than others is a most fundamental topic to link amphibian decline research with conservation on the ground (e.g., Savage &Zamudio, 2011). Consider, for instance, a scenario where the fungus acts as a primary killing agent and is able to extirpate healthy individuals in otherwise pristine environments. This differs widely from a case of death by increased susceptibility to infection in the presence of environmental stressors. Differentiating between these two possibilities is a topic still under study, but they will clearly require distinct management strategies. Although we recommend the study of both proximate and ultimate causes of anuran declines, we suggest that authors be as explicit as possible in their reports. Need for integration We encourage scientists to think broadly when studying declining amphibian populations. As recently emphasized (Hayes et al., 2010), death and recruitment failure are the two clear causes of population crashes. Many factors can contribute to these general phenomena, both singly and in synergistic ways. Pathogens, environmental pollutants and atmospheric change can act at one level, and significantly influence more obvious and measurable factors such as disease and developmental failure (Hayes et al., 2010). Climate change can lead to warmer breeding seasons, resulting in lower body condition, lower survival rates and lower fecundity of female frogs (Reading, 2007). Field studies suggest that climate-driven habitat change leads to amphibian decline (e.g., Daszak et al., 2005). Pesticide contamination and non-native fish continue to negatively affect amphibian populations (Davidson, 2004; Gillespie, 2010). It is thus clear that amphibian conservation transcends herpetology and herpetologists. Rather than a taxon-specific problem, the amphibian crisis is a reflection of

9 Navas et al. 127 anthropogenic global change (Pounds et al., 2008). Reducing the problem to one or two study foci (climate change vs. pathogen emergence, for instance; e.g., Rohr et al., 2008) results in oversimplification of an intrinsically complex issue. The best research strategy to understand the causes of anuran declines is to think outside the herpetological box and establish networks of collaborations, gathering field biologists, systematists, climatologists, geologists, landscape and disease ecologists, geneticists. Steps in this direction have been praised in the literature (Collins &Crump, 2009: xvii) and are being taken by many research groups: all of the 20 top-cited papers discussed above have authorship representing a diversity of institutions and disciplines. Local integrative studies are likely the best building blocks toward appropriate generalized amphibian conservation measures (e.g. Woodhams et al., 2003). Need for experimental studies and critical interpretation of results Although the detection of correlative patterns is a crucial step in uncovering causal processes in biology, the overarching use of correlative evidence in amphibian decline research comes at a toll. Rather than using indirect evidence (e.g., metadata) to re-analyze or re-test existing hypotheses about the underlying causes of amphibian declines, scientists are better off, and make more efficient use of time and resources, by experimentally testing some of the hypotheses already posed by colleagues. For instance, in vertebrate ectotherms, temperature is known to affect both components of host-pathogen interactions, not only the pathogen (Berger et al., 2004; Hayes et al., 2010). This has been largely ignored in the amphibian decline literature, yet can be investigated under controlled conditions. Likewise, it is important to keep in mind the limits of the experimental data. Batrachochytrium dendrobatidis grows differently at colder vs. warmer temperatures under laboratory conditions (Woodhams et al., 2008). Yet, these assays only minimally reflect the optimal infecting temperatures experimented in the field, and even less the eco-geographic zones where infection is more likely to occur. Although incorporating complexity in experimental studies can be challenging, even small controlled change in tested conditions can be very telling. Given the complexity of amphibian declines, fair interpretations of results and a language that admits no doubt regarding such interpretations are a must if we are to adequately implement scientifically-based conservation measures. Individual scientists are ultimately responsible for avoiding inconsistencies in their arguments, but there is something to be said about the role of the peer review system. Associated editors and referees can be invaluable by identifying inconsistencies and ensuring that novel articles move the field forward. Recommendations: science as a process Training of human resources Although amphibian decline research should be largely multi-disciplinary (e.g., Richards-Zawacki, 2010), most scientists have been trained as specialists in one or two areas. This calls for collaborative research and cross-talk among disciplines: a strategy that has a much higher likelihood to arrive at sound conclusions relative to single-authored

10 128 ALYTES 29 (1 4) ventures to unfamiliar fields. Amphibian conservation on the ground will greatly benefit from training programs that support trans-disciplinary thinking in young scientists coupled with collaborative research. Funding A most important link between amphibian decline research and conservation on the ground is funding prioritization. In recent years, significant financial resources have been allocated to single topics of interest, such as surveys for evidence of chytrid and captivebreeding programs (via small, private or NGO-based conservation programs), and emergent disease research (e.g., through larger agencies such as the National Science Foundation). Yet, funding strategies can help us cast a wider net for research that encompasses the inevitable synergistic mechanisms influencing amphibian populations. Amphibian declines have a number of well documented context-specific causes that do include B. dendrobatidis outbreaks, but not exclusively so. Consequently, chytrid-centric funding policies will fail to lead us very far. Leverage of funding for interdisciplinary work, transformative and exploratory studies, experimental research (including much needed advances in anuran physiology) and basic field biology will lead us to the right path towards effective amphibian conservation. Scientific communication Complex technical papers are often ineffectual to most policy makers and fail to inform and engage communities where conservation efforts must be applied. A key aspect of conservation biology is rooted in the ability of scientists to make findings clear to those implementing conservation policies NGOs, governments, public and private institutions. Making complex scientific information accessible to an educated, yet non-specialist audience is a challenge on its own that highlights the need of truly interdisciplinary actions in the context of amphibian conservation. Not only are scientists seldom trained to deal with the media, but they often feel like their words are taken out of context. More efficient communication between biologists and professional communicators will greatly help amphibian conservation. As in other living groups, amphibian diversity must be interpreted and protected as the result of both historical and contemporary processes. However, a look through recent commentaries in high-impact journals and press releases indicates that this balance is somewhat tilted. Strong emphasis, for instance, has been given to short-term mediation such as captive breeding programs (e.g., Mendelson et al., 2006). Although useful and timely, these strategies alone will by no means solve the amphibian decline problem. It is upon us to educate the general public about the complexity of amphibian declines, and make clear the role that each and every citizen has on the fate of such beautiful creatures. Acknowledgements We are grateful to the editors for the invitation to submit our paper to this special journal edition. We appreciate their careful reviews and comments, and also those received from two anonymous reviewers. A. Carnaval acknowledges funding by NSF (DEB ).

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