Drones (unmanned aerial vehicles, UAVs), are an advanced technology that allows the collection of large amounts of data in a short amount of time, including the detection of cryptic and arboreal animals. Here, we report the first records of the southern maned sloth Bradypus crinitus obtained with thermal cameras from a drone. As far as we know, this is the first time a sloth has been observed by a drone. We recorded four individuals of B. crinitus in the Brazilian Atlantic Forest, plus first records of Procyon cancrivorus, which were all resting in the forest canopy. The individuals’ thermal responses demonstrate that the use of drones for research on these species may be a viable option to study still unexplored aspects of their ecology or conservation.
Funding source: Conselho Nacional de Desenvolvimento CientÃ-fico e TecnolÃ³gico
Award Identifier / Grant number: 300845/2022-7
Award Identifier / Grant number: 300893/2022-1
Award Identifier / Grant number: 318063/2021-2
The authors thank the Augusto Ruschi Biological Reserve and all ICMBio team for the logistical support.
Author contributions: PMS, MCK, DOM, FRM, and SLM conducted the fieldwork and conceptualized the study; PMS led the writing; all authors edited and approved the manuscript.
Research funding: This study was supported by the Programa de Capacitação Institucional from Instituto Nacional da Mata Atlântica (PCI/INMA), which also provided fellowships via CNPq to PMS (300893/2022-1), MCK (318063/2021-2), and DOM (300845/2022-7).
Research ethics: All the procedures were in accordance with the national laws. The drone is registered at the National Aviation Agency (ANAC), through the Unmanned Aircraft System (SISANT), and for each flight we ask for authorization by SARPAS. There is also a mandatory insurance against third parties, called Reta.
Conflict of interest statement: The authors declare that they have no conflicts of interest regarding this article.
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This article contains supplementary material (https://doi.org/10.1515/mammalia-2022-0123).
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