Dados do Trabalho

Título:

EACH FLIGHT, A SURPRISE: FIRST RECORDS OF THE MANED THREE-TOED-SLOTH (BRADYPUS TORQUATUS: BRADYPODIDAE) THROUGH DRONES

Resumo:

The maned three-toed sloth (Bradypus torquatus, Illiger 1811) is a strictly arboreal and exclusively folivorous species. This endemic species inhabits an almost exclusively dense ombrophilous forest along the Brazilian Atlantic coast, in the following states: Sergipe, Bahia, Espírito Santo, and Rio de Janeiro. Due to its restricted habits and distribution, this species is considered threatened and classified as Vulnerable by the national and international red lists. One of the greatest challenges of working with sloths is their low detection rates in forested areas due to their cryptic nature and their tendency to inhabit the highest reaches of the forest. Thus, the use of unmanned aerial vehicles - drones - can help in the identification and visualization of this species in its natural habitat. Several studies have used this new technology to assess biodiversity conservation, and its benefits can be extended through the use of thermal cameras that allow individuals to be identified by their body's emission of heat. On May 14 and 15, 2022, we flew over the Augusto Ruschi Biological Reserve (ARBR), Santa Teresa, ES, Brazil, using a drone model DJI Mavic 2 Enterprise Advanced. We were able to record four individuals on two different occasions and at different locations within the area. On the 14th, at 3pm, we observed two individuals, and on the 15th, in the early morning on a rainy day, we also identified two individuals in another area of ​​the ARBR. In total, it took about 30 minutes to find 4 individuals, generating an effort of 8 indiv/h. Sloths are generally heterothermic species, with a labile body temperature varying with the environment, due to their slow metabolism and low muscle mass percentage. This poor body temperature regulation left it in doubt whether it was possible to identify it through thermal cameras, allied to inhabiting dense ombrophilous forests. However, the good spectral response shown by these individuals demonstrates that drones can also be used to monitor this species and collect different types of data, including density – hitherto unknown for the species. Despite the current high cost of the thermal camera for drones, they have been shown as an efficient tool for improving and advancing different types of biodiversity studies.

Financiamento:

PMS, AG, DOM e MCK recebem bolsa do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) nº 300893/2022-1,300889/2022-4, 300845/2022-7 e 318063/2021-2, respectivamente. FRM has support from Wildlife Conservation Society and ReWild.

Área

Conservação