Morphological characteristics are known to be important predictors of victory in aggressive disputes in the animal world. Among anurans, however, acoustic communication also plays an important role in intrasex conflicts. Although there is evidence for the influence of spectral parameters of calls (e.g., fundamental and dominant frequencies) in anuran disputes, the role that temporal parameters (e.g., duration and repetition rate) play in success during physical conflicts is still poorly understood. We describe the behavior of male frogs in agonistic interactions and investigate the functions of the different types of calls emitted in different social contexts. We also evaluate how body characteristics (mass and body size) and bioacoustic characteristics (repetition rate of the calls) influence success in physical conflicts of Pithecopus nordestinus (Anura: Phyllomedusidae). Agonistic disputes involved gradation in the emission of calls, visual displays, and physical clashes. The fighting call increased in proportion during clashes, indicating a function associated with aggression/intimidation. The uneasiness call (new subcategory herein defined) was only performed by losers during physical clashes, suggesting a meaning of submission or restlessness. No differences were found in any of the morphological parameters between winners and losers of physical disputes. On the other hand, the repetition rate of the aggressive call was positively related to success in fights and proved to be a good predictor of success in fights between males of P. nordestinus. Our results contribute to understanding the influence of temporal parameters of calls on success in physical disputes of this Neotropical treefrog.

The treefrog Pithecopus nordestinus emits aggressive calls during agonistic interactions between males, but how these vocalizations vary between contexts with different levels of aggression remains unknown. Herein, we compared the acoustic parameters of aggressive calls emitted during physical disputes and out of fight contexts. The aggressive calls emitted during physical clashes (Fighting Calls) presented a repetition rate, duration and number of pulses significantly higher than those emitted out of fight contexts. Our results expand the knowledge about acoustic repertoire of Phyllomedusidae treefrogs and contribute to the understanding of the effects of social tension on the vocal behavior of anurans.

Natural areas within cities are important as they contribute to maintain biodiversity and the functioning of ecosystems. In Ceará state, inventories of birds in human-impacted areas are still scarce. Here, we inventory bird species and estimate the species richness at Parque Ecológico Lagoa da Fazenda, an urban park in the municipality of Sobral, in northeastern Brazil. We found 82 bird species, of which 16 breed in the area, three are endemics, and three others are introduced. Despite the moderate species richness detected, richness estimators revealed that sampling was sufficient to detect most species. To maintain or even increase local species richness, we suggest the cessation of urban expansion within the park, sewage dumping, and filling of the wetland, as well as further planting of native vegetation.

The Sete Cidades National Park is located in the Brazilian municipalities of Piracuruca and Brasileira, Piauí state, in a transitional zone between the Caatinga and Cerrado biomes. Studies on its herpetofauna were limited to anuran distribution notes and a snake checklist. Thus, here we present an unpublished species list of anurans from Sete Cidades National Park, Piauí state, northeastern Brazil. We recorded one of the two highest species richness for all northeastern National Parks, and also increased the geographic distribution of one species in the state of Piauí. Most species observed are common of both Caatinga and Cerrado biomes or have wide distribution in Brazil. The anuran assemblage of Sete Cidades National Park is more similar to those registered at the Delta do Parnaíba Environmental Protection Area, Ceará, Piauí and Maranhão states, and Ubajara National Park, Ceará state. These results increase our knowledge on anuran diversity in northeastern Brazil, providing basic information for management and conservation actions of an important Brazilian National Park.

Among the forms of anthropogenic disturbance, agricultural land use is one of the main threats to biodiversity. Understanding how interactions between parasites and hosts are affected by agricultural land use allows predictions of how these anthropogenic impacts affect parasites. Although parasitism patterns are affected by agricultural land use, it is noteworthy that different groups of parasites can respond differently to these environmental alterations. While heteroxenous species need more than one host to complete their life cycle and tend to be more harmed by anthropization, monoxenous species, which need only one host to complete their life cycle, tend to be less harmed. In this work, we evaluate how agricultural land use affects the abundance and prevalence of parasitism for monoxenous and heteroxenous helminths in the generalist lizard Tropidurus hispidus in Caatinga Domain, Brazil. We recorded differences in abundance and prevalence of heteroxeneous (higher in conserved areas) and monoxenous helminths (higher in agricultural areas). Heteroxenous helminths that have lizards as definitive hosts are mainly obtained through diet. Tropidurus hispidus predominantly consumes insects, so it is possible that the lower abundance and prevalence of heteroxenous parasites in agricultural areas, beyond habitat simplification, is related to the decrease in the insect population. As monoxenous species do not need an intermediate host, it is possible that this aspect has influenced their greater success in anthropogenic environments than heteroxenous species. This contrasting result reinforces the need for a separate assessment between these groups when evaluating effects of land use.

Animal monitoring research involving mark-recapture techniques increasingly requires non-invasive methods of individual identification. The photographic identification method (PIM) is an excellent tool for this purpose and has been applied successfully to many taxa. However, the utility of PIM is a function of species-specific features that are judged suitable for a given target-species. Herein, the suitability of inguinal color patterns for photo identification of individuals of Pithecopus gonzagai are evaluated by comparing two widely used computer-assisted photographic matching programs (I³S and Wild.ID). Both programs accurately identified more than 70% of individuals in the top 20 potential matching photographs. Wild.ID was slightly better than I³S in matching efficiency and has a faster processing time. Thus, PIM is useful to identify individual P. gonzagai; however, before implementing the technique in animal-monitoring studies of other taxa, one must evaluate the suitability PIM for the target species and calibrate the relative efficiency of the software programs in identifying individuals.

Anthropogenic changes in habitats are one of the main threats to biodiversity. Understanding how species diversity and their functions are affected by these changes is crucial to assess environmental impacts. In this work, we aim to understand how lizard composition, taxonomic and functional diversity respond to differences in native vegetation regeneration stages (conserved vegetation and open secondary vegetation) and agricultural land use in different vegetation types (Caatinga sensu stricto, Cerrado sensu stricto and Relictual Humid Forest) in Caatinga domain, Brazil. In more degraded areas (open secondary vegetation and agricultural areas), we found a decline in species evenness, shown by greater dominance of few species. Moreover, we found a lower functional evenness in agricultural areas than in areas of conserved vegetation, which suggests that a smaller portion of functional traits present greater dominance in more anthropized areas. We did not detect any significant differences in species richness, but we did registered differences in species composition in Relictual Humid Forest. Contrary to our expectations, lizard abundance was also greater in more degraded areas, probably as a result of the increased abundance of species benefited by anthropization. In this work, we advance the knowledge of how anthropogenic changes influence lizard diversity and emphasize the importance of analysing different facets of diversity and different habitat environments to understand how anthropization affects patterns in community ecology.

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