Abstract The presence of humans frequently modifies the behavior of animals, particularly their foraging patterns, compromising energetic demands. The fiddler crab Leptuca leptodactyla inhabits mangroves with high degrees of anthropogenic influence. Thus, we tested if populations living in highly anthropized mangroves respond differently from those living in more protected areas. We predict that individuals from touristy areas will be more tolerant to humans and will resume their activities sooner after disturbance. To do so, we conducted an experiment that consisted in the approach of an observer to the burrows, recording the response of individuals to the stimuli. The experiment took place in July 2022, in Ubatuba, São Paulo, Brazil. We analysed the duration and latency of various behaviors of a total of 80 adult males from two populations (high and low anthropogenic influence). Contrary to our predictions, individuals from the anthropized population were less tolerant, spending more time inside their burrows and taking longer to resume their activities. Therefore, fiddler crabs were not habituated to human presence. These results help us understand the learning process in invertebrates and their ability to select stimuli, contributing to understanding the impacts of human-wildlife interactions. animals patterns demands influence Thus disturbance so stimuli 2022 Ubatuba Paulo Brazil 8 . influence) predictions Therefore humanwildlife wildlife interactions 202 20 2

ABSTRACT Binomial nomenclature in Latin is used to name species, allowing communication between scientists but not with the general public. We compiled popular names in Portuguese, Spanish, and English for the rodent species that occur in Brazil, revealing a large gap in Portuguese, where 11.5% of the species do not have common names, or they share a same name, as 66 of the Echimyidae (“toró”), and 57 of the Cricetidae species (“rato-do-mato”). In contrast, almost all species have common names in English, which are generally unique. To highlight the importance of ecosystem services that rodents provide to society, it is essential to provide common names in the local language where the species was described. public Portuguese Spanish Brazil 115 11 5 11.5 6 toró, toró , (“toró”) ratodomato. ratodomato rato mato . (“rato-do-mato”) contrast unique society described 1 11. (“toró” (“rato-do-mato” (“toró (“rato-do-mato

Resumo Pequenos roedores dependem da aquisição de recursos para sustentar a reprodução e a sobrevivência da ninhada. Uma vez que plantações podem servir como fonte complementar de alimento, nós avaliamos a influência da presença de plantações de milho na borda da floresta sobre a abundância e a reprodução de Oligoryzomys nigripes (Olfers, 1818). Constatamos que a abundância, a proporção de indivíduos reprodutivos, assim como o número de juvenis foram maiores nas bordas dos campos de milharal, sem sazonalidade, um padrão divergente da reprodução sazonal descrita para a espécie. Nossos resultados suportam a hipótese de que as plantações de milho beneficiam a abundância e a atividade reprodutiva de O. nigripes.

Abstract Small rodents rely on resource gathering during the breeding season to support their reproductive output and offspring survival. Since croplands may provide complementary food sources, we evaluated the influence of the presence of cornfield on the forest edge in Oligoryzomys nigripes (Olfers, 1818) abundance and breeding. We found that abundance, proportion of reproductive females and males, as well as the number of juveniles were higher in the cornfield-forest edges, with no seasonality, a pattern divergent from the seasonal reproduction described for the species. Therefore, our results supported the hypothesis of cornfields benefiting O. nigripes abundance and breeding success.

Introduction: We analyzed the variation in the age structure, sex ratio, proportion of reproductive individuals, age and size at sexual maturity, and litter size in a population of the sigmodont rodent Wiedomys pyrrhorhinos. We compared the observed distributions with the monthly rainfall for the same period, to identify the reproductive period and to assess the effects of the rains on the age structure of the population during the ensuing months. We further compared our results with age structure patterns recovered from other documented rodent outbreaks to identify possible causes of a presumptive population outbreak represented by this series. Methodology: Museum samples had been obtained between July 1953 and February 1955 from 40 sites in Caruaru, Pernambuco, Brazil (Fig. 1, Appendix). Records from a total of 2,280 individuals, 1,834 of which represented by their skulls, were analyzed. Skulls were sorted into seven age classes based on molar eruption and wear (Fig. 3). Monthly rainfall during the entire collecting period (Fig. 2) was analyzed for putative correlations with monthly frequencies of specimens (Figs. 4 and 5) and of indicators of reproductive condition, tabulated for each sex and age class. Results: Monthly frequency distributions of age classes presented separated and consecutive modal peaks, conforming to an age structured population (Fig. 6). Monthly proportions of pregnant females were highly correlated with the amount of rainfall of the same and of the previous month (Fig. 7), although records of pregnant females were obtained every month between July 1953 and December 1954. Pregnant females were found from age class 2 on. From January to April, 1954, reproductive females belonged to age classes 5 to 7. From May to September a wide range of age classes was documented among pregnant females, and from October to December only those of age classes 2 to 4 were recorded (Fig. 8). Litter size varied throughout the year, with larger averages and ranges at mid-wet season (June-August) (Fig. 10) and was highly correlated with female weight, female length and with the amount of rainfall of the previous 30 days. Higher means in litter size were also in phase with higher proportions of pregnant females and with the age class 1 peak. Discussion and Conclusion: The population peak occurred four to six months after the rainfall peak (September - November) and was primarily comprised of young adults. After this period, the pregnancy rates were very low, ceasing completely by January, 1955, when most of the individuals belong to older age classes. This shift in age structure from younger to older individuals during population decline indicated that the samples documented an outbreak episode in 1954. This episode was possibly related to the unusual rainfall in November 1953, apparently sufficient to support two closely-spaced breeding seasons, with the second amplifying the effect of the first.

Hemos analizado la variación en la estructura etaria, proporción sexual, proporción de individuos reproductivos, edad y grado en la madurez sexual, y el tamaño de la prole en una población del roedor sigmodontino Wiedomys pyrrhorhinos, con base en una gran serie de individuos obtenida entre julio de 1953 y febrero de 1955 en Caruaru, Pernambuco, Brasil. Se registraron 2,280 individuos, de los cuales 1,834 están representados por cráneos, los que fueron analizados. Los cráneos fueron agrupados en siete clases de edad basadas en la erupción y desgaste molar. La proporciones mensuales de hembras grávidas tuvieron una alta correlación con la cantidad de lluvia del mismo mes y del mes anterior, a pesar de que la variación han sido encontradas también durante la estación seca. El tamaño de la prole varió a lo largo del año, con valores más altos durante mediados de la estación húmeda (junio), y este fue altamente correlacionado al peso, el largo del cuerpo de la hembra y con la lluvia de los 30 días anteriores. Distribuciones de frecuencias mensuales de clases de edad presentaron máximos modales consecutivos y separados, ajustándose a una población estructurada de manera etaria. El máximo poblacional ocurrió de 4 a 6 meses después del máximo de lluvias (septiembre-noviembre) y estaba compuesto primariamente por jóvenes adultos. A partir de ese período, sin embargo, las tasas de gravidez fueron muy bajas, cesando completamente en enero, cuando la mayoría de los individuos pertenecía a clases etarias más viejas. Ese cambio en la estructura etaria, de los más jóvenes a individuos más viejos durante el descenso poblacional, indicó que la muestra disponible sufrió un surto poblacional en 1954. Este episodio fue posiblemente relacionado a un aumento poco común en las lluvias en noviembre de 1953, aparentemente suficiente para soportar dos estaciones reproductivas enmendadas.