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The improvement of techniques and analyses to understand the movement of freshwater turtles has helped managers in decision-making and the establishment of management strategies for these animals, which suffer numerous threats. We analyzed the available scientific literature on the use of telemetry in the study of the movement ecology of freshwater turtles, seeking to assess the most commonly used approaches. To this end, we carried out a systematic review of articles published until December 2022 using the PRISMA protocol. We found 104 articles published between 1980 and 2022, with a clear increase in the number of publications in later years. We found publications in 40 journals with 295 authors, 150 institutions and 261 keywords. Three countries had major contributions, and we found studies with 50 species, the most recurrent being Emydoidea blandingii and Glyptemys insculpta. The most commonly used technique to study turtle movement was radiotelemetry. The use of Minimum Convex Polygon – MCP and Kernel Density Estimation – KDE was present in 56% of the studies in the last 10 years, and the evaluation of the home range of the species was the most recurrent type of study. The studies covered 33 freshwater ecoregions, and although most studies were carried out in anthropized areas, covering only 16.2% of all endangered freshwater turtle species and 11.4% of all threatened by international trade, the conservation approach has been increasingly recurrent. Our results highlight trends and gaps in the study of the ecology of freshwater turtle movements and highlight the importance of telemetry as an essential tool for species conservation. Highlights: This study reviews 104 articles on telemetry in aquatic turtles, highlighting the predominant use of radiotelemetry. It reveals a focus on anthropized areas and significant gaps, with only 16.2% of endangered species studied. The research underlines the importance of telemetry in turtle ecology conservation. Conservation efforts are growing, despite existing gaps." [ABSTRACT FROM AUTHOR]

This is the first multiple months study on home range and habitat use by a small group of bushmaster (Lachesis spp.). Five snakes (natives and translocated) were intensively radio tracked in a mosaic of plantations and small fragments of Atlantic Forest in the Reserva Ecologica Michelin in Bahia, Brazil. The average home range was 9.47 ha (MCP 95%) and 44.11 (Kernel 95%) for bushmasters tracked for more than 6 months. The macrohabitats used were primarily composed of disturbed primary (partially logged) and secondary (originally cleared) forests, but also of rubber tree plantations with a dense understory vegetation. Activity centres were closer to the forest edge (~ 22 m) than the core of the small forest fragments. The snakes mainly occupied wooded microhabitats with complex vegetation structures, around 50% under- and mid-story cover. Nocturnal ambush differed from diurnal resting microhabitats on the surface mainly by being significantly closer to mammal trails and a more open understory space. While mammal burrows and refuges under roots and rocks have been used, diurnal resting was primarily on the forest floor (75%). Translocation from sites > 20 km outside the study site has produced little evidence of negative effect, as all individuals grew impressively, continued an apparently normal life and established a home range similar to native bushmasters. [ABSTRACT FROM AUTHOR]

Understanding the diet of tadpoles is fundamental to explain their ecological roles in aquatic food webs, as well as to allow more effective amphibian conservation and management programs. Studies on trophic ecology of tadpoles are scarce compared to other vertebrate groups, a gap that is even more accentuated in the Neotropical region, which harbors the greatest diversity of anuran species worldwide. The objective of this study was to describe the diet of the tadpole of Macrogenioglottus alipioi, from a population in southern Bahia, Brazil. Gut contents of 30 tadpoles were analyzed under light microscope. Additionally, the intestinal contents of 15 tadpoles were analyzed under a stereoscopic microscope to verify the presence of larger food items such as macroinvertebrates. Algae were the most important microscopic food item in the diet of M. alipioi tadpoles. Mites occurred in 80% of the analyzed specimens and represented the most important macroscopic food source, followed by insect fragments from dipterans, lepidopterans and spiders. The tadpoles of M. alipioi can be considered omnivorous consumers. As in benthic tadpoles from other species, diatoms, protozoans and small metazoans are considered important food sources in the diet of tadpoles. Additionally, the analysis of gut contents under a stereoscopic microscope identified several food items that were not recorded by analyses performed under light microscope. [ABSTRACT FROM AUTHOR]

Behavioral changes constitute a common response of aquatic animals to predator chemical and/or visual cues. Tadpoles frequently use such signals to evaluate predator presence/activity and, consequently, alter their own behavior to reduce detectability and susceptibility to predation. The present study aimed to test how tadpoles of Bokermannohyla martinsi and Ololygon machadoi respond to the presence of a predator (Belostoma testaceopallidum), regarding background choice and activity levels. Results showed that O. machadoi tadpoles increased the use of yellow backgrounds in the presence of the predator perceived through either chemical or visual cues. Bokermannohyla martinsi, on the other hand, did not show preference for any specific background color or changed activity levels in the presence of any predator cue. Our results corroborate the hypothesis of disruptive coloration as a defense strategy in O. machadoi and indicate that the visible and active tadpoles of B. martinsi may employ a different defensive strategy, possibly relying on a more efficient post detection escape mechanism. This hypothesis is corroborated by the higher activity levels of B. martinsi and lack of response to predator presence regarding either modulation of activity levels or background choice. [ABSTRACT FROM AUTHOR]

Extinctions of anuran amphibians are more alarming compared to all other vertebrates. Several reports of declines come from Atlantic Forest, which currently holds only 1.62% of natural vegetation under full protection. However, despite this degradation, the Atlantic Forest still shelters a great diversity of anurans with a high diversity of specific ecological characteristics. Thus, our objective was to identify which ecological characteristics of anurans from the Atlantic Forest can be associated to this extinction risk, in order to understand how these characteristics can promote the species persistence against environmental disturbance. For each species, we gathered biological/ecological characteristics from literature, as well the extinction risk based on the National List of Endangered Species of Wildlife. In 2015, 547 anuran species had been assigned to the Atlantic Forest, of which 406 had their extinction risk defined. However, we considered only 295 species in our analyses due to the availability of biological/ecological information. We observed that the clutch size and the altitudinal distribution are related to the extinction risk of anurans. Threatened species had a small clutch size and were distributed in low or high areas, whereas non-threatened species had a larger clutch size and were distributed in intermediate altitude areas. Studies that investigate ecological characteristics that determine the extinction risk of species can be useful to assist conservation actions, concentrating efforts to species more sensitive to environmental alterations, besides highlighting the importance of natural history and the ecology of organisms in conservation decisions. [ABSTRACT FROM AUTHOR]

In the present study we used larval amphibians (Rhinella jimi) as prey, and beetle larvae (Hydrophilus sp.) as predator to assess if increased water temperature influences predator-prey dynamics. The experiment was carried out in replicated aquatic microcosms with two different water temperatures (control and a 'warming water' scenario). Survival of tadpoles decreased significantly in the treatment compared to the control and at the end of the experiment, all tadpoles in the 'warming water' scenario had been ingested, unlike in the control treatment, where only half of the tadpoles were ingested. Our results demonstrate that the alterations in abiotic conditions (water temperature) can reshape predator-prey dynamics in a future scenario of global warming. The consequent increase of predation may intensify negative effects on population size in anuran larvae. Although changes are likely, they are complex and often counterintuitive. [ABSTRACT FROM AUTHOR]

Current biodiversity patterns of Neotropical amphibians are the result of their functional and phylogenetic relationships. Understanding the associations between ecological similarity and phylogenetic relatedness among species can provide a convincing statement on the role of evolutionary history in the filling of the niche space. Here, we assessed the ancestral character states of amphibian ecological traits and their evolutionary history in the Atlantic Forest Hotspot. We used 12 genes (11,906 bp) to reconstruct a phylogeny for 207 amphibian species and related it to eight ecological traits regarding their morphology, life-history and behavioural features. We revealed that closely related species can have similar ecological traits, suggesting that these traits are driven by phylogenetic history. Despite the high endemism rate of Atlantic Forest amphibians, our findings heavily rely on good studies on complete amphibian phylogenetic lineages to overcome potential biogeographical constraints. Using mechanisms of adaptive evolution in the context of phylogenetic diversification, we suggest that closely related species have different phylogenetic signals and ecological traits can evolve without relatedness. [ABSTRACT FROM AUTHOR]

To coexist, two species should use available resources in different ways. These differences may happen in three different dimensions: temporal, spatial and trophic. In frogs, differences in trophic dimensions are mainly due to different sizes and types of ingested prey. We studied the diet of two syntopic Pithecopus species, addressing prey selectivity and sharing of food resources. Fieldwork was undertaken at the Michelin Ecological Reserve, southern Bahia, between the years 2011 and 2012. Stomach contents were retrieved using a flushing procedure and data on prey availability was obtained. Of the 16 invertebrate categories found in the environment, 11 were consumed by P. rohdei and 12 by P. nordestinus, features that characterize a generalist diet. The most abundant category in the diet of P. nordestinus was Diptera while Hemiptera was the most consumed prey category for P. rohdei. Trophic niche overlap was high considering the size of ingested prey and lower for categories. The selectivity index showed that both species used the resources available in the environment in a slightly different way. The differences found concerning trophic ecology of these two species seem to be sufficient to allow coexistence in the studied area. [ABSTRACT FROM AUTHOR]

Of the currently known 75 species within the four recognized species groups of Leptodactylus, the L. fuscus group contains 30 species, of which tadpoles are known for 24, including L. plaumanni described based on a population from Argentina. Herein, we describe external and internal oral morphology of L. plaumanni tadpoles collected in Brazil and compare with tadpoles from Argentina. In addition, we compare phenetic groups obtained from analysis of larval characters with the currently recognized species groups. The tadpole of L. plaumanni from Brazil is identified by: body globular in lateral view, ventral fin forming a wide arc, oral disc lateroventrally emarginate, marginal papillae of oral disc biseriate, more than 10 papillae on each side delimiting the mouth floor, and buccal roof arena trapezoidal. Of the 23 analyzed external morphological characters, only eight were shared by tadpoles from Argentina and Brazil, and they also shared 14 of the 15 internal oral morphological characters. Tadpoles of both populations differ in external morphology and, although such intraspecific differences can be due to plasticity, the hypothesis that these two populations represent different species cannot be dismissed. Phenetic groups obtained using larval characters are consistent with species groups proposed for Leptodactylus by phylogenetic analysis, based on adult characters. [ABSTRACT FROM AUTHOR]

Mosquito-borne diseases have been spreading rapidly. Although Aedes sp. are believed to prefer man-made habitats for reproduction, its larvae can also be found in bromeliads in anthropic environments. Mosquito populations can be controlled through predation, in which the relative size of predator and prey are important to understand this interaction. Tadpoles of Phyllodytes luteolus live in bromeliad axils and are potential predators of mosquito larvae. Our aim was to assess if these tadpoles are able to prey mosquito larvae, and if the predation rate differs according to the size of predator and prey. We collected P. luteolus tadpoles and Culicidae mosquito larvae from bromeliads of restinga (sandbank) areas. We measured the total length of tadpoles and mosquito larvae, and separated them into three size categories (large, medium and small). As experimental units, we used 50 mL centrifuge tubes with 35 mL of dechlorinated water, without substrate and food. We applied nine treatments composed by a combination of tadpole size categories and mosquito larvae size categories. In each unit, we added one tadpole and five mosquito larvae to evaluate the overall predation rate after 4 days. We found that P. luteolus tadpoles of any size were able to prey on mosquito larvae and verified that large tadpoles preyed a larger number of mosquito larvae than smaller size categories. Our results can contribute to evaluate the importance of tadpoles in the trophic structuring of aquatic environments, especially in phytotelmata. [ABSTRACT FROM AUTHOR]

This work describes the diet of a population ofAdenomera thomeifrom a rubber tree plantation within the Atlantic Rainforest of Brazil. Individuals were measured and treated with a stomach flushing method. We assessed the correlation between morphometric aspects and stomach contents and compared electivity with the available invertebrate fauna in the leaf litter. The most important item in the diet was Formicidae. We found 2.48 prey items per stomach. Electivity was highest for isopods. We conclude thatA. thomeiis a sit-and-wait forager that, despite feeding mainly on ants, cannot be considered an ant specialist because it selects other prey items present in their environment. [ABSTRACT FROM PUBLISHER]

Territoriality is common among amphibians with a prolonged breeding season and can be expressed through the defence of territories with vocalizations and aggressive interactions. The present study aims to describe the territorial behaviour of male Phyllomedusa nordestina, test whether the physical characteristics of males influence the results of disputes, and describe the vocalizations of the species. The study was conducted at temporary and permanent ponds located in the Ecological Reserve Michelin, Igrapiuna, Bahia, Brazil. Male P. nordestina defended territories and showed aggressive behaviour, consisting of vocal disputes, chasing and physical fighting. Winners were not bigger, heavier, or in better condition than the losers. The victory may be associated with the vocalization activity. Three types of vocalizations were recorded: the advertisement call, composed of one or two multipulsed notes, and two types of territorial calls. We also report on male patrolling behaviour and habitat use. [ABSTRACT FROM AUTHOR]

We analysed the diet of Ischnocnema henselii from a subtropical Araucaria forest through stomach flushing. The identified prey items comprised arthropods such as spiders, ants, orthopterans, collembolans and homopterans. We consider I. henselii to be a nocturnal and opportunistic sit-and-wait predator. Small animals are preferred. Because this species lives permanently on the forest floor, we also determined the composition of the habitat's leaf-litter mesofauna. By using Winkler sieve extraction, we obtained a spectrum of small invertebrates that reflected the prey in the stomach contents well. The only exceptions were mites, the most abundant leaf-litter inhabitants, which frogs either avoided or ignored. Our results represent the first information on the diet of I. henselii and are discussed in comparison with data on related species and in relation to the relevance of this predator within the food web of subtropical montane rain forests in southern Brazil. [ABSTRACT FROM AUTHOR]

The diet of males of five syntopic hylid species from the Araucaria plateau of Rio Grande do Sul was studied by stomach flushing. Because the duration of their breeding seasons was rather different, the levels of food intake at the respective breeding sites were analysed. We found a positive correlation between the length of the male calling period and the ingestion of prey. The longer the species-specific reproductive activity of the males, the more individuals fed during that time. The results are discussed under congruence aspects of feeding and mating microhabitats in these tree frogs. In addition, differences in niche breadth may influence the temporal and spatial partitioning between the species studied and result in quantitative as well as qualitative patterns of prey consumption, thereby ensuring a maximum of fitness gain. [ABSTRACT FROM AUTHOR]

Stomach-flushing is a gentle treatment in analysing the diet of vertebrates. We applied this method in the study of seasonal nutrition of anurans of 15 species at an Araucaria forest habitat on the Serra Geral of Rio Grande do Sul, Brazil. Over 500 frogs and toads of different body size were handled in order to evaluate an improved protocol without narcosis using soft infusion tubes in order to avoid negative effects of the flushing procedure. The specimens were treated soon after capture and then returned to the sampling sites. Our results are discussed with reference to the few studies on stomach flushing in amphibians. The improved technique is recommended to avoid killing of numerous animals for nutritional studies, in particular because of the worldwide threatening of amphibian populations. [ABSTRACT FROM AUTHOR]