The Use of Multiple Biomarkers to Assess the Health of Anuran Amphibians in the Brazilian Cerrado Savanna: An Ecotoxicological Approach.

Changes in the natural landscape and the indiscriminate use of pesticides can have a major impact on aquatic environments and have contributed to the worldwide decline of amphibian populations. In the present study, we sampled tadpoles of three anuran amphibians (Boana albopunctata, Physalaemus cuvieri, and Dendropsophus minutus) from ponds in six different agricultural landscapes of the Brazilian Cerrado savanna and evaluated whether and to what extent genotoxic and mutagenic damage was related to land use (the amount of forest and agricultural remnants, and related physicochemical factors) and the presence of pesticides in the water of the study ponds. We also evaluated the hepatotoxicity in P. cuvieri, which was the most abundant species at five of the six sampling points. Clomazone and atrazine were the most common pesticides found in the ponds. The B. albopunctata and P. cuvieri tadpoles presented similar patterns of DNA damage among the sampling points. The least DNA damage was found in the D. minutus tadpoles, although this species was present in only one of the study ponds. More binucleated and anucleated cells were observed in B. albopunctata, but there was no significant variation among species in terms of the number of micronuclei or other erythrocytic nuclear abnormalities. Land use and physicochemical factors did not explain the variation in the DNA damage observed in the three anurans. The hepatotoxicity analyses of P. cuvieri revealed the presence of a series of alterations, including the enlargement of the sinusoids, vacuolization of the hepatocytes, the infiltration of inflammatory cells, hepatic steatosis, and dilation of the blood vessels. The interaction between physicochemical factors and the biomarkers analyzed in the present study is complex. In particular, it will be important to better elucidate which factors are contributing, either directly or indirectly, to the decline of anuran amphibian populations, especially in threatened biomes, such as the Brazilian Cerrado. In this case, we would encourage further in situ studies that assess the ecotoxicology of the landscape, together with the systematic monitoring of aquatic environments, to guarantee the long-term integrity of amphibian populations, and those of other organisms that play an essential functional role in the ecosystem. Environ Toxicol Chem 2023;42:2422-2439. © 2023 SETAC.

Multi-taxon inventory and landscape characterization in an agrosystem of the Brazilian Midwest targeted for payment for environmental services / Inventário multi-táxon e caracterização da paisagem em um agrossistema no Centro-Oeste brasileiro alvo de pagamento por serviços ambientais

Abstract: The replacement of natural landscapes by anthropic environments has led to habitat loss and consequently, to the decline and extinction of many species populations. Several strategies, such as the creation of protected areas (PAs) and payment for ecosystem services have been adopted to mitigate the consequences of this biodiversity crisis. In Rio Verde, Goiás, Brazil, a Water Producer Program (WPP) was established, which provides payment for ecosystem services for the maintenance of riparian vegetation in the region of the Ribeirão Abóbora, a river which supplies the city and metropolitan area. In the absence of environmental diagnostic studies in the region, this present study contributes to reducing some knowledge gaps, through the: (i) characterization of the landscape in the WPP area, (ii) characterization of species of fauna (amphibians, birds, fish, and medium and large terrestrial mammals) and woody flora that occur in this area, and (iii) comparison of species diversity (fauna and flora) found in our study area with the diversity observed in the Cerrado protected area network. Our results reveal a low native vegetation cover (~21% of total area), but we recorded 300 total species: 20 species of anuran amphibians, 100 birds, 10 fish, 16 terrestrial mammals (medium and large), and 154 woody plants. Our sample comprises species considered endemic to the Cerrado (e.g., Anuran - Barycholos terntezi and Mammal - Callithrix penicillata), threatened species (e.g., Mammals - Herpailurus yagouaroundi, Myrmecophaga tridactyla and Tapirus terrestris), and exotic invasive species (Mammal - Sus scrofa). The results presented in this study are relevant and may help in the proposal of management actions within the scope of this important program of payment for environmental services.

Resumo: A substituição das paisagens naturais por ambientes antropizados tem levado à perda de habitat e, consequentemente, ao declínio populacional e extinção de muitas espécies. Várias estratégias como a criação de Unidades de Conservação (UCs) e o pagamento de serviços ecossistêmicos têm sido adotadas para mitigar as consequências da crise de biodiversidade. Em Rio Verde, estado de Goiás, foi estabelecido um Programa Produtores de Água (PPA) que prevê o pagamento de serviços ecossistêmicos pela manutenção da vegetação ripária na região do ribeirão Abobora que abastece a cidade. Diante da ausência de estudos de diagnóstico ambiental da região, o presente estudo contribui para reduzir algumas lacunas de conhecimento, através da: i) caracterização da paisagem na área deste PPA, ii) caracterização das espécies da fauna (anfíbios, aves, peixes e mamíferos terrestres de médio e grande porte) e flora lenhosa que ocorrem neste local, iii) comparação da diversidade de espécies (fauna e flora) encontrada na área de estudo com aquela observada na rede de áreas protegidas do Cerrado. Nossos resultados revelam baixo índice de cobertura vegetal nativa (~21% da área total), mas por outro lado, registramos 300 espécies, sendo 20 de anfíbios anuros, 100 aves, 10 peixes, 16 mamíferos terrestres (médio e grande porte) e 154 plantas lenhosas. A nossa amostragem compreende espécies que são consideradas endêmicas do Cerrado (p.ex. Anfíbio - Barycholos terntezi e Mamífero - Callithrix penicillata), ameaçadas de extinção (p.ex. Mamíferos - Herpailurus yagouaroundi, Myrmecophaga tridactyla e Tapirus terrestris) ou exótica invasora (Mamífero - Sus scrofa). Os resultados apresentados no presente estudo são relevantes e podem auxiliar na proposição de ações de manejo no âmbito deste importante programa de pagamento por serviços ambientais.

The aggressive call of Dendropsophus cruzi (Pombal Bastos, 1998) (Anura; Hylidae) in Central Brazil.

Dendropsophus cruzi (Pombal Bastos, 1998) is a small hylid (male snout-to-vent length = 16.3-19.4 mm; female SVL = 21.3-25.0 mm) that is allocated in the D. microcephalus group (Faivovich et al. 2005). It is commonly found in Open and forested areas from Central Brazil to Provincia Velasco, Departamento de Santa Cruz, Bolivia (Frost 2017; Tessarolo et al. 2016). Pombal Bastos (1998) described the advertisement call of D. cruzi as a single pulsed note. Posteriorly, studies uncovered relationships between dominant frequency variation in the advertisement calls of D. cruzi and variation in the SVL and mass of males (Bastos et al. 2003), as well as the existence of a clinal geographic pattern in the variation of acoustic parameters of these calls (Tessarolo et al. 2016). However, the acoustic communication in anurans is usually mediated by more than one vocalization type (Toledo et al. 2015). Due the importance of call types in the social context of anurans (e.g., Reichert 2011; Forti et al. 2017), we expand the vocal repertoire of D. cruzi by describing its aggressive call.