Temperature shapes the daily temporal distribution of Neotropical mammals

Abstract

Behavioural adaptations in response to environmental changes is commonly found in wild animals. Such adaptations can be both on the spatial and the temporal scale, with the majority of previous studies focusing on the spatial adaptations. However, temporal activity patterns are also affected by a variety of environmental factors. In this camera trap study, I compare the daily activity budgets of seven mammal species occurring in two vastly different biomes (the Amazon and the Caatinga) to assess whether their activity is influenced by temperature. Animal activity patterns were compared using Kernel density analysis with accompanying coefficients of overlap, while a generalized linear model determined the influence of temperature. For five out of seven study species, activity patterns in the Amazon and in the Caatinga were distinctly different, while all species showed relatively similar patterns within the Amazon. Caatinga animals were much more nocturnal than in the Amazon and appeared to avoid activity during the hottest hours of the day. Temperature had a significant effect on temporal distribution of all species in at least one location, but only on four species in the Caatinga. Jaguars, pumas and ocelots were highly affected by temperature in the Caatinga, but generally not in the Amazon. Results therefore indicate that some species have altered their diel activity patterns to different environments across the Amazon and the Caatinga biomes. This seems to be influenced by the high temperatures in the Caatinga. These results suggest that species may be able to adapt to the increasing temperatures caused by climate change by becoming more nocturnal.