Increasing human population size is increasing the demand for resources like timber, oil, tea, coffee, and other crops. Plantation crops mimic some aspects of native habitats, and there are studies that report the presence of some native anuran biodiversity in plantations. I focused on tea plantations in the Western Ghats-Sri Lanka Biodiversity Hotspot and studied the diversity and health of anurans in different habitats found within a tea cultivation area, near Munnar region in the Western Ghats, India. The landscape includes tea bushes, native evergreen shola forest patches, and eucalyptus forest stands. I reviewed 40 studies comparing amphibian species richness in plantations and primary forests. The age of the plantation, type of plantation, presence in a biodiversity hotspot, number of species in the dominant plantation type, number of species in the paired forest habitat, and latitudinal zone of the study, did not correlate with species richness, but plantations that had periodic harvesting had higher species richness than plantations that practiced clear-cut harvesting. I tested different methods of standard amphibian sampling in the field season 2012 in Munnar, and found that Visual Encounter Surveys (VES) in the shola habitat and Stream Transects (ST) were the most efficient. Using the VES and ST methods, I sampled amphibians in three upland habitats (tea, shola, and eucalyptus) at four different sites, and 150m of stream transects at each site, for two consecutive monsoon seasons. Fourteen species were encountered in both years and the community structure was similar across the years. The community structure at the four sites that was driven by the presence of exclusive species at each site and species composition in streams was similar across the landscape and was driven by the presence of similar species in streams across the four sites. Two hundred and sixteen anurans of 17 species, were tested for the presence of the lethal fungus Batrachochytrium dendrobatidis. The preliminary results from the Polymerase Chain Reactions were negative. My study provides baseline data for anuran diversity, composition, and health in the Munnar region of India and results of this project can be compared with tea plantations around the world.

Several mechanisms mediate the richness, diversity, abundance and distribution of tadpoles in the ponds. The purpose of this study was to characterize the composition of tadpoles of an area of Caatinga in the State of Sergipe and evaluate it with respect to use temporal (time of occurrence) and spatial (within the preferred local water bodies) in the dams. Looking for understand the influence of some environmental parameters and predators on the abundance of tadpoles. The study was conducted at the Natural Monument Grota Angico in the period September 2011 to August 2012. The sample of tadpoles and predators were doing in nine dams of the locality. The biotic and abiotic factors were collected monthly in the dams that had water. 2117 tadpoles and 710 predators were collected. The alpha diversity was similar between the dams and the beta diversity was considered relatively low. Most tadpoles had high spatial niche breadth showing a general use of space. The spatial and temporal overlaps showed segregation between species in the use of micro-habitats and seasons. None of the species showed association between their abundances and the physical-chemical and structural of the dams. The richness and abundance were correlated to rainfall. Tadpoles and predators differed on the use of micro-habitat and only three species showed a positive correlation with the predators. The results were in some ways similar to other studies in the Caatinga biome and in dry areas of the country. Studies in the Caatinga are still a challenge to researchers, especially about the frogs of the Biome, and studies should be encouraged, so that you can know more about the biology of these species and so you can get better conservation strategies for the group. / Diversos mecanismos mediam a diversidade, riqueza, abundância e distribuição dos girinos nos corpos d água. O objetivo do estudo foi caracterizar a composição de girinos de uma área de Caatinga no Estado de Sergipe e avaliá-la em relação ao uso temporal (períodos de ocorrência) e espacial (locais preferenciais dentro dos corpos d água) nos açudes. Buscando ainda, compreender a influência de alguns parâmetros ambientais e de predadores, em potencial, sobre a abundância dos girinos. O estudo foi realizado no Monumento Natural Grota do Angico, no período de Setembro de 2011 a Agosto de 2012. A coleta dos girinos e predadores foi realizada em forma de parcela em nove açudes da localidade. Os fatores bióticos e abióticos foram coletados mensalmente nos açudes que possuíam água. Foram coletados 2117 girinos e 710 predadores. A diversidade alfa foi semelhante entre as lagoas e a beta foi considerada relativamente baixa. A maioria dos girinos teve amplitude de nicho espacial elevada mostrando um uso generalista do espaço e, as sobreposições espacial e temporal demonstraram uma segregação entre as espécies no uso de micro-habitat e dos períodos de ocorrência. Nenhuma das espécies apresentou relação entre suas abundâncias e os fatores físico-químicos e estruturais dos açudes. A riqueza e abundância estiveram relacionadas a pluviosidade. Girinos e predadores diferiram quanto ao uso do micro-habitat e apenas três espécies apresentaram correlação positiva com os predadores. Os resultados obtidos foram em alguns aspectos semelhantes a outros estudos realizados no bioma Caatinga e em áreas secas do país. Evidenciou-se a importância dos açudes na manutenção das populações locais e a necessidade de preservação dos mesmos. Estudos na Caatinga ainda perfazem um desafio aos pesquisadores, principalmente a cerca da anurofauna do Bioma, e estudos devem ser incentivados, tanto para que se possa conhecer mais sobre a biologia larval dessas espécies quanto para que se possa obter melhores estratégias de conservação para o grupo.

Orientador: Célio Fernando Baptista Haddad / Resumo: As forças de seleção natural e sexual atuam sobre os indivíduos e podem os levar ao isolamento reprodutivo. O acúmulo de modificações evolutivas pode levar ao surgimento de novas entidades. Espécie é unidade basal em biologia; assim, com sua exuberante biodiversidade, a Mata Atlântica é uma floresta neotropical fundamental para estudos de processos evolutivos em anfíbios anuros. Reunindo os gêneros Cycloramphus, Thoropa e Zachaenus, a família Cycloramphidae agrupa espécies de anuros saxícolas e terrestres, todas endêmicas da Mata Atlântica brasileira. Pelos seus hábitos especializados de vida e reprodução, os cicloramfídeos formam um grupo atrativo para estudos evolutivos. Na presente tese são apresentados quatro capítulos que abordam três escalas distintas da evolução: a diversificação entre espécies, populações e indivíduos. São abordados: (1) a filogenia molecular multilocus de Cycloramphus-Zachaenus, demonstrando que a evolução da terrestrialidade no clado se correlaciona com o dimorfismo sexual em tamanho; (2) a diversificação fenotípica associada a diversificações genéticas em populações de C. boraceiensis e C. dubius, demonstrando que estas duas espécies-irmãs saxícolas apresentam zona de contato e hibridação; (3) o sistema de acasalamento promíscuo e as relações sociais em C. boraceiensis, demonstrando que tamanho das fêmeas e dos machos e parentesco genético influenciam a formação dos casais; e (4) o sistema de acasalamento poligínico com fidelidade na espécie saxíco... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Natural and sexual selection forces act on individuals and may lead to reproductive isolation. The increase in evolutionary modifications may lead to the emergence of new entities. Species is the basal unity in biology; thus, with its exuberant biodiversity, the Atlantic rainforest is a fundamental Neotropical forest for studies of evolutionary processes in anuran amphibians. Comprising the genera Cycloramphus, Thoropa, and Zachaenus, the family Cycloramphidae gathers saxicolous and terrestrial anuran species, all endemic to the Brazilian Atlantic rainforest. Because of their specialized life and reproductive habits, cycloramphids are an attractive group for evolutionary studies. In the present thesis we show four chapters that address three distinct scales of evolution: the diversification among species, populations, and individuals. We goaled: (1) the multilocus molecular phylogeny of Cycloramphus-Zachaenus, demonstrating that the evolution of terrestriality in the clade is correlated with the sexual size dimorphism; (2) the phenotypic diversification associated with the genetic diversifications in populations of C. boraceiensis and C. dubius, demonstrating that these two saxicolous sister species show a contact zone and hybridization; (3) the promiscuous mating system and the social relations in C. boraceiensis, demonstrating that female and male sizes, and mate relatedness influence pair formation; and (4) the polygynic mating system with fidelity in the saxicolous specie... (Complete abstract click electronic access below) / Doutor

Limited breeding success in captive breeding programs has necessitated the development of assisted reproductive technologies (ART) to preserve and increase genetic variation and population numbers of both captive and wild amphibian groups. ART has been shown to be successful in numerous anuran species, and current studies focus on the application of ART in ex-situ populations. The focus of this project is to show that linking in-situ and ex-situ amphibian populations through sperm cryopreservation, genome banking, and in-vitro fertilization is possible, with the goal of increasing gene diversity throughout groups in order to produce self-sustaining, wild populations in the future. Specific objectives include developing a sperm-cryopreservation methodology using sperm from the model species Anaxyrus fowleri, applying this protocol to the cryopreservation of spermatozoa from two other threatened anurans to determine protocol transmissibility, and linking in-situ and ex-situ populations of an endangered species using cryopreserved sperm form wild males to produce viable offspring.

Amidst the amphibian extinction crisis, in situ and ex situ amphibian species conservation initiatives utilize assisted reproductive technologies for optimal genetic management of captive and wild populations. Development of effective, simple, low-cost methods for obtaining gametes for artificial fertilization, sperm biobanking, or natural breeding alleviates obstacles for institutions or programs to apply reproductive technologies. Objectives herein include investigating the efficacy of alternative hormones for inducing spermiation, an alternative hormone administration route for inducing ovulation, exploring the physiological effects of hormone therapy, and utilizing sperm from deceased animals for biobanking.

Apesar dos habitats de restinga representarem aproximadamente 5.000 km da costa brasileira, o conhecimento disponível sobre a composição da fauna de anuros nestes habitats ainda é restrito a poucas áreas. Estes habitats encontram-se sob intensa pressão imobiliária, com uma densidade demográfica cinco vezes maior do que a média do país, levando a uma ocupação descomedida, degradação e eventual perda destes importantes habitats. Isso é especialmente preocupante para as populações de vertebrados terrestres endêmicos e ameaçados de extinção, devido à dificuldade de recuperação da vegetação das restingas. Atualmente, os remanescentes de restinga ao longo da costa brasileira são representados por fragmentos completamente isolados. Esta é a primeira aproximação da lista de anfíbios da restinga de Grumari, inserida no Parque Natural Municipal de Grumari (PNMG), município do Rio de Janeiro, sudeste do Brasil. É também a primeira pesquisa a analisar a comunidade de anuros de folhiço, e a obter dados de densidade, para as restingas brasileiras. A área está situada no Domínio da Mata Atlântica. O estudo foi conduzido de maio de 2009 a dezembro de 2010 utilizando dois métodos de amostragem: parcelas grandes ou plots de 16 m (4x4 m) e transecções visuais/acústicas. Registramos 22 espécies de anfíbios anuros distribuídas em seis famílias: Leptodactylidae (3), Craugastoridae (1), Bufonidae (1), Strabomantidae (1), Microhylidae (2) e Hylidae (14). Ocorreram dez espécies de anuros de folhiço em 2560 m de chão de floresta amostrados com a metodologia de parcelas grandes durante o estudo. Na zona fechada de pós-praia ocorreram apenas sete espécies de anuros de folhiço, enquanto na mata de restinga ocorreram as dez espécies registradas para a restinga. A densidade geral estimada de anuros de folhiço para a restinga de Grumari foi de 13,1 indivíduos por 100m, superior a cinco de seis estudos publicados com dados de densidade de anuros de folhiço na Mata Atlântica. A biomassa total estimada foi de 13131 g/ha, podendo ser considerada a maior biomassa de anurofauna de folhiço globalmente. Não houve diferença estatisticamente significativa entre as zonas quanto aos parâmetros da comunidade (riqueza, densidade e biomassa), mesmo havendo diferença entre os parâmetros ambientais mensurados nas duas zonas. Os fatores que melhor explicaram a riqueza, a densidade e a biomassa na restinga de Grumari durante a estação chuvosa foram, respectivamente, a temperatura, o diâmetro das árvores/arbustos e o número de árvores/arbustos. A presença de espécies ameaçadas de extinção e endêmicas para o estado do Rio de Janeiro e Mata Atlântica evidencia que a restinga de Grumari é uma área essencial para a conservação da anurofauna dos remanescentes deste habitat no Brasil. Além disso, Grumari é a restinga com maior riqueza de espécies do estado e a segunda maior entre todas as áreas de restinga estudadas até o momento, quanto à anurofauna. / Although restinga habitats represent approximately 5000 km of the Brazilian coast, the information available about the composition of the anuran fauna present on those habitats are restricted to relatively few areas. Nowadays restinga habitats are under intense set of pressures as result of a demographic density five times higher than the average for the country leading to the occupation, degradation and eventual loss of such habitats. This is especially alarming for the threatened endemic populations of terrestrial vertebrates due to the difficulty of vegetation recovery after clearings. Presently, the remnants of these habitats along much of the eastern Brazilian coast are represented by completely isolated fragments. Herein we present the first approximation to the list of the amphibians from the restinga of Grumari, inserted in the Parque Natural Municipal de Grumari (PNMG), municipality of Rio de Janeiro, Rio de Janeiro state, southeastern Brazil. The area is situated in the Atlantic Rainforest Biome. Its also the first study on the community of litter anuran fauna, obtaining density data, for the Brazilian restinga. The study was carried out from May 2009 to December 2010 using two sampling methods: quadrant plots (4x4 m) and acoustic/visual transects. We recorded 22 species of anuran amphibians distributed in six families: Leptodactylidae (3), Craugastoridae (1), Bufonidae (1), Strabomantidae (1), Microhylidae (2) and Hylidae (14). We found ten species of litter frogs in 2560 m of sampled forest floor with the methodology of large plots. In the closed post-beach zone, there were only seven species of anuran leaf litter, while the restinga forest zone present the ten species recorded for the restinga. The overall density of litter frogs at the restinga of Grumari was 13.1 individuals per 100m, more than five of six published studies on the density of litter frogs in the Atlantic Rainforest. The estimated total biomass was 13131 g/100m, being currently the area with highest litter frog biomass on the planet. There was no statistically significant difference between the zones regarding community parameters (richness, density and biomass), even though there is difference between the environmental parameters measured in both zones. The factors that best explained the richness, density and biomass in the restinga of Grumari during the rainy season were, respectively, temperature, diameter of the trees/shrubs and the number of trees/shrubs. The presence of endangered and endemic species indicates that the restinga of Grumari is an important area for conservation of the anuran fauna in remnants of these habitats in the Rio de Janeiro state, being currently the richest known area in terms of amphibian species of all restinga areas in the state, and the second richest of the Brazilian restingas studied up to now.

Apesar dos habitats de restinga representarem aproximadamente 5.000 km da costa brasileira, o conhecimento disponível sobre a composição da fauna de anuros nestes habitats ainda é restrito a poucas áreas. Estes habitats encontram-se sob intensa pressão imobiliária, com uma densidade demográfica cinco vezes maior do que a média do país, levando a uma ocupação descomedida, degradação e eventual perda destes importantes habitats. Isso é especialmente preocupante para as populações de vertebrados terrestres endêmicos e ameaçados de extinção, devido à dificuldade de recuperação da vegetação das restingas. Atualmente, os remanescentes de restinga ao longo da costa brasileira são representados por fragmentos completamente isolados. Esta é a primeira aproximação da lista de anfíbios da restinga de Grumari, inserida no Parque Natural Municipal de Grumari (PNMG), município do Rio de Janeiro, sudeste do Brasil. É também a primeira pesquisa a analisar a comunidade de anuros de folhiço, e a obter dados de densidade, para as restingas brasileiras. A área está situada no Domínio da Mata Atlântica. O estudo foi conduzido de maio de 2009 a dezembro de 2010 utilizando dois métodos de amostragem: parcelas grandes ou plots de 16 m (4x4 m) e transecções visuais/acústicas. Registramos 22 espécies de anfíbios anuros distribuídas em seis famílias: Leptodactylidae (3), Craugastoridae (1), Bufonidae (1), Strabomantidae (1), Microhylidae (2) e Hylidae (14). Ocorreram dez espécies de anuros de folhiço em 2560 m de chão de floresta amostrados com a metodologia de parcelas grandes durante o estudo. Na zona fechada de pós-praia ocorreram apenas sete espécies de anuros de folhiço, enquanto na mata de restinga ocorreram as dez espécies registradas para a restinga. A densidade geral estimada de anuros de folhiço para a restinga de Grumari foi de 13,1 indivíduos por 100m, superior a cinco de seis estudos publicados com dados de densidade de anuros de folhiço na Mata Atlântica. A biomassa total estimada foi de 13131 g/ha, podendo ser considerada a maior biomassa de anurofauna de folhiço globalmente. Não houve diferença estatisticamente significativa entre as zonas quanto aos parâmetros da comunidade (riqueza, densidade e biomassa), mesmo havendo diferença entre os parâmetros ambientais mensurados nas duas zonas. Os fatores que melhor explicaram a riqueza, a densidade e a biomassa na restinga de Grumari durante a estação chuvosa foram, respectivamente, a temperatura, o diâmetro das árvores/arbustos e o número de árvores/arbustos. A presença de espécies ameaçadas de extinção e endêmicas para o estado do Rio de Janeiro e Mata Atlântica evidencia que a restinga de Grumari é uma área essencial para a conservação da anurofauna dos remanescentes deste habitat no Brasil. Além disso, Grumari é a restinga com maior riqueza de espécies do estado e a segunda maior entre todas as áreas de restinga estudadas até o momento, quanto à anurofauna. / Although restinga habitats represent approximately 5000 km of the Brazilian coast, the information available about the composition of the anuran fauna present on those habitats are restricted to relatively few areas. Nowadays restinga habitats are under intense set of pressures as result of a demographic density five times higher than the average for the country leading to the occupation, degradation and eventual loss of such habitats. This is especially alarming for the threatened endemic populations of terrestrial vertebrates due to the difficulty of vegetation recovery after clearings. Presently, the remnants of these habitats along much of the eastern Brazilian coast are represented by completely isolated fragments. Herein we present the first approximation to the list of the amphibians from the restinga of Grumari, inserted in the Parque Natural Municipal de Grumari (PNMG), municipality of Rio de Janeiro, Rio de Janeiro state, southeastern Brazil. The area is situated in the Atlantic Rainforest Biome. Its also the first study on the community of litter anuran fauna, obtaining density data, for the Brazilian restinga. The study was carried out from May 2009 to December 2010 using two sampling methods: quadrant plots (4x4 m) and acoustic/visual transects. We recorded 22 species of anuran amphibians distributed in six families: Leptodactylidae (3), Craugastoridae (1), Bufonidae (1), Strabomantidae (1), Microhylidae (2) and Hylidae (14). We found ten species of litter frogs in 2560 m of sampled forest floor with the methodology of large plots. In the closed post-beach zone, there were only seven species of anuran leaf litter, while the restinga forest zone present the ten species recorded for the restinga. The overall density of litter frogs at the restinga of Grumari was 13.1 individuals per 100m, more than five of six published studies on the density of litter frogs in the Atlantic Rainforest. The estimated total biomass was 13131 g/100m, being currently the area with highest litter frog biomass on the planet. There was no statistically significant difference between the zones regarding community parameters (richness, density and biomass), even though there is difference between the environmental parameters measured in both zones. The factors that best explained the richness, density and biomass in the restinga of Grumari during the rainy season were, respectively, temperature, diameter of the trees/shrubs and the number of trees/shrubs. The presence of endangered and endemic species indicates that the restinga of Grumari is an important area for conservation of the anuran fauna in remnants of these habitats in the Rio de Janeiro state, being currently the richest known area in terms of amphibian species of all restinga areas in the state, and the second richest of the Brazilian restingas studied up to now.

Examiner les liens existant entre la variabilité environnementale, les traits d'histoire de vie, la dispersion et les décisions d'accouplement est un enjeu central en Ecologie et en Evolution. J'ai exploré ces questions chez un amphibien, le sonneur à ventre jaune (Bombina variegata). Dans le premier volet de ma thèse, je me suis intéressé à l'influence des variations spatiotemporelles de l'environnement sur les patrons de covariation entre les traits d'histoire de vie, la dispersion et les types comportementaux à l'échelle inter-populationnelle. J'ai examiné comment le degré de stochasticité interannuel de l'habitat de reproduction régule le positionnement des populations le long du slow-fast continuum et génère des syndromes de dispersion parmi les populations. J'ai ensuite analysé les conséquences de ces syndromes sur les patrons de différenciation génétique au sein des populations. Dans le second volet de ma thèse, je me suis intéressé au rôle de la canalisation environnementale dans la stratégie d'histoire de vie de B. variegata et j'ai évalué comment diverses formes de variations météorologiques pouvaient affecter la dynamique de différentes populations. Dans chacune d'elles, j'ai mesuré l'impact de facteurs météorologiques sur des paramètres démographiques tels que la survie, le recrutement et les probabilités de reproduction. Dans le troisième et dernier volet de ma thèse, je me suis intéressé au choix d'accouplement des femelles, en examinant successivement les hypothèses de bons gènes et de gènes compatibles puis en me focalisant sur le rôle de la qualité et de la disponibilité des sites de reproduction sur les décisions d'accouplement des femelles / Investigating the links between environmental variability and life history traits, dispersal and breeding decisions is critical challenge for ecologists. I have examined this issue in anuran, the yellow-bellied toad (Bombina variegata). In the first part of my thesis, I have examined the influence of spatio-temporal variation of the environment on the covariation patterns between life history traits, dispersal and behavioral types at inter-population scale. I have investigated how the level of breeding habitat stochasticity may regulate the position of B. variegata populations along the slow-fast continuum and may promote dispersal syndromes among populations. Then I have analyzed the consequence of such dispersal syndromes on population genetic differentiation. In the second part of my thesis, I have focused on the role of the environmental canalization in the life history strategy of B. variegata and I have evaluated how various forms of weather variation (mean and extreme events) could affect the dynamics of different populations. In each studied populations, I have quantified the impacts of weather variation on various demographic parameters as survival, recruitment and breeding probabilities. In the third part of my thesis, I have investigated female mate choice in B. variegata by successively examining good genes and compatible gene hypotheses, and then by evaluating the role of breeding habitat quality and availability on mating decisions

Many polycyclic aromatic compounds (PACs) are toxic, carcinogenic, and mutagenic. As a result, their effects on aquatic biota and ecosystems are of great concern. Research on PACs in aquatic biota often overlooks the role of amphibians, alkylated PACs, and sediment as an uptake route. In order to study the accumulation and toxicokinetics of PACs following sediment and aqueous exposure, and to compare the bioaccumulation potentials of parent and alkyl PACs, two accumulation-elimination experiments using wood frog tadpoles (Lithobates sylvaticus) of Gosner stage 28-32 were conducted (one evaluating exposure to contaminated sediment and water, and the other to contaminated water alone). A complementary field study was then conducted near Fort McMurray, Alberta to assess PAC body burdens in field-collected amphibian larvae, and to determine whether PAC body burdens are related to exposure to sediment and/or water in the field. The results of our studies showed that PAC concentrations and uptake rates in wood frog tadpoles were highest when they were exposed to PAC-contaminated sediment. Consequently, we determined that the dominant route of exposure of wood frog tadpoles to PACs is sediment rather than water. This finding supports other studies that have shown dietary uptake to be an important route of PAC exposure in other aquatic organisms. In both the laboratory and field study, alkyl PAC concentrations exceeded those of parent PACs in wood frog tadpoles, which also demonstrated petrogenic PAC profiles. Interestingly, parent PACs seemed to have greater bioaccumulation potential than alkyl PACs in the laboratory-exposed wood frog tadpoles (in relation to sediment), possibly due to greater bioavailability or lower metabolism of parent PACs or alternatively, due to a saturation in uptake of alkyl PACs. Nevertheless, only a few compounds, including anthracene, fluoranthene, retene, and C1-benzofluoranthenes/benzopyrenes, were found to have higher bioaccumulation potentials. Lithobates sylvaticus tadpoles seemed to be efficient at eliminating and metabolizing both parent and alkyl PACs. However, the elimination of some compounds, such as C4-naphthalenes, was not as efficient. Furthermore, C3-fluorenes and C2-dibenzothiophenes were isolated as potential markers of amphibian larvae exposure to PAC-contaminated sediment due to their positive correlation with the wetland sediment concentrations. Additional field collections in the Athabasca oil sands are warranted to verify the utility of these markers in the natural environment. Evidently, this thesis highlights the importance of including sediment exposure and alkylated PACs in toxicological and field studies of benthic and epibenthic organisms. The results of this study are the largest, most comprehensive set of toxicokinetic and bioaccumulation information of PACs (52 analytes) in the amphibian larvae Lithobates sylvaticus obtained to date.

Alien fish have been implicated in the decline of Rana draytonii (California red-legged frog) and Pseudacris regilla (Pacific treefrog) populations. Micropterus salmoides (largemouth bass) is a common sport fish that has been introduced into the sympatric range of these two anuran species; however, no studies have investigated the individual influence that this alien fish has on these two species. I conducted M. salmoides control or eradication experiments during a four year study in two ponds within the Transverse Mountain Range of Santa Barbara County, California. Changes in the densities of all life stages of R. draytonii and P. regilla were assessed through repeated visual encounter surveys. In response to the manipulations of the M. salmoides populations there was an increase in the density of both species. For R. draytonii, this salient increase in density was recorded in the larval and metamorph life stages. For P. regilla, a slight, yet steady increase in the density of adult, metamorph, and larval life stages was recorded. My results suggest that M. salmoides can be controlled or eradicated from lentic waterbodies and provides reasonable evidence that the negative effects of this species on R. draytonii and P. regilla populations can be minimized or reversed. The reversal of these effects may translate into increases in the densities and potential recruitment of these two native anurans. Therefore, my results provide tentative support that the control or eradication of M. salmoides where they cohabitate with these two species may be a viable conservation measure for R. draytonii and P. regilla populations. Since my study was performed at a very local scale and all results are strictly observational and descriptive, additional studies should be performed at a larger spatial scale and buttressed with controlled laboratory and field enclosures experiments to identify the causal factors responsible for the identified patterns.