A predominantly diurnal tropical mammal increases nocturnality in response to high temperatures

• Published in: Biotropica 2024-01, Vol.56 (1), p.18-27
• Main Authors: Peterson, Michaela C., Jorge, Maria Luisa S. P., Keuroghlian, Alexine
• Format: Article
• Language: English
• Subjects: Air temperature; behavioral flexibility; Climate change; Climate prediction; Daily; Data loggers; Diurnal; Flexibility; High temperature; Mammals; Microclimate; Nocturnal; Taxa; Temperature; Thermoregulation; tropical forest; Vulnerability; white‐lipped peccary
• ISSN: 0006-3606; 1744-7429
• DOI: 10.1111/btp.13271

The extent to which animals may compensate for rising temperatures through behavioral thermoregulation is an important unknown in predicting responses to climate change. Flexibility in temporal activity in particular may be an important factor in determining species' vulnerability. In this study, we examine whether the white‐lipped peccary, a predominantly diurnal Neotropical mammal, shifts its temporal activity and microclimate selection in response to daily temperature variation in the Pantanal biome of Brazil. From November 2021 to October 2022, we deployed camera traps and microclimate data loggers to record white‐lipped peccary activity and air temperature on a fine spatiotemporal scale. We found that the percentage of peccary activity that is nocturnal increased with maximum daily temperature at a rate of 3.7% per 1°C past a threshold of 31.2°C, and increased with maximum daily wet‐bulb temperature at a rate of 4.7% per 1°C past a threshold of 24.9°C. The afternoon period (i.e., solar noon to sunset) went from having the highest frequency of peccary activity at the lower end of our observed temperature range to having the lowest frequency of activity at the higher end. We did not find evidence of microclimate selection. Our findings indicate that white‐lipped peccaries in the Pantanal demonstrate substantial behavioral flexibility in their response to high temperatures, which may help to buffer them against the impact of rising temperatures caused by climate change. in Portuguese is available with online material. Resumo Determinar a capacidade de animais de compensar o aumento das temperaturas atraves de termorregulação comportamental sera fundamental para prever respostas às mudanças climáticas. Certa flexibilidade na distribuicao de atividade ao longo do dia pode ser um fator importante em determinar a vulnerabilidade das espécies. Neste estudo, examinamos se a queixada (Tayassu pecari), um mamífero neotropical predominantemente diurno, altera sua atividade diaria e seleção de microclima em resposta à variação da temperatura na região do Pantanal (Brasil). De novembro de 2021 a outubro de 2022, colocamos armadilhas fotográficas e coletores autonomos de dados microclimáticos para registrar a atividade de queixadas e temperatura do ambiente em uma escala espaço‐temporal mais fina. Nossos resultados mostram que a porcentagem de atividade noturna das queixadas aumentou com o aumento da temperatura diária máxima, a uma taxa de 3,7% por 1°C, acima de um