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Museum specimens and citizen science initiatives are valuable sources of information on how anthropogenic activities affect biodiversity and how species respond to rapid global change. Although tropical regions harbor most of the planet's biodiversity, investigations on species' phenological changes are heavily biased toward temperate regions. Such unevenness in phenological research is also taxonomically biased, with reptiles being the least studied group among tetrapod species regarding animal phenology. Herein, we used long‐term time‐series data to investigate environmentally driven changes in the activity pattern of tropical forest snakes. We gathered natural history collection and citizen science data for 25 snake species (five venomous and 20 non‐venomous) from an Atlantic Forest region in southeastern Brazil. Using circular mixed‐effects models, we investigate whether snake activity patterns followed the variation in environmental variables over a decade. Our results show that the activity pattern of Atlantic Forest snakes was seasonal and largely driven by average temperature and relative humidity. Since snakes are ectothermic animals, they are particularly sensitive to temperature variations, especially at small scales. Moreover, relative humidity can affect snake's seasonal activities through physiological constraints and/or prey availability. Most specimens were registered during the rainy season, with highly venomous snakes (lanceheads and coral snakes) emerging as the most abundant taxa. We highlight the importance of citizen science and natural history collections in better understanding biodiversity. Furthermore, our data obtained from local collectors underscore the need for environmental education programs and collaboration between researchers and local decision‐makers to raise awareness and reduce conflicts between people and snakes in the region. [ABSTRACT FROM AUTHOR]

A plethora of semi‐aquatic species perform seasonal migrations to reproduce, with migration timing often relating to several factors. Human‐induced environmental changes may disrupt the migration phenology of many taxa. Improving our knowledge on drivers of migration phenology helps to elucidate the impacts of climate change upon biodiversity. Herein, we applied circular analyses to investigate how biological and environmental factors affect the migration phenology of leaf litter frogs in an Atlantic forest remnant. We observed the synchronous arrival at ponds of adults Physalaemus, likely due to its short breeding period and opportunistic breeding strategy. Large‐sized females arrived earlier than small‐sized ones at the ponds likely due to their higher movement potential. Temperature, precipitation and photoperiod affected the immigration phenology of females, but not of males. Only photoperiod affected emigration phenology of male Physalaemus. The higher responsiveness of females to environmental cues suggests they migrate when environmental conditions are optimal. Lastly, the emigration phenology of juvenile Physalaemus occurred in 'bursts', with precipitation likely triggering departure from ponds. Overall, we showed that sex‐related differences in responses to environmental cues could exacerbate phenological shifts in amphibian migrations due to environmental changes, and potentially impact the mating success of forest‐dependent pond‐breeding species. [ABSTRACT FROM AUTHOR]

We present information on the reproduction of Gymnodactylus darwinii based on macroscopic analysis of its gonads. We found no sexual dimorphism in body size (SVL) between adult males and females, but males had, on average, wider heads and longer forearms. Both sexes had very similar sizes at sexual maturity and maximum body sizes, suggesting male–male competition for resources does not occur, and/or there are no sexual differences in survival rates. The smallest specimen had 24 mm SVL, and juvenile/immature specimens of similar or slightly bigger sizes were collected throughout the year suggesting a continuous turnover of individuals in the population. Adult males showed a continuous reproductive cycle, contrasting with a seasonal cycle of females, where maximum gonadal volume was observed from September to December. This is not uncommon and may be related to differential response to local environmental conditions, or because distinct investment in reproduction. Females have a small and fixed clutch size (two eggs per clutch), a pattern also observed in its congener G. amarali and in many geckonids, which is likely due to phylogenetic inertia. To compensate for a fixed clutch size, females may be able to lay more than one clutch per reproductive season. [ABSTRACT FROM AUTHOR]