Sloth Science and Research
The Sloth Conservation Foundation is committed to advancing knowledge through rigorous, high-quality research. Our studies are published in open-access, peer-reviewed journals, ensuring that our findings are accessible to the global scientific community and beyond.
We proudly collaborate with leading universities around the world, including the University of Manchester, Brown University, and Swansea University, to deepen our understanding of sloth biology, ecology, and conservation.
Published Research
Host specificity of gastrointestinal parasites in free-ranging sloths from Costa Rica | 2025
We co-authored the first study comparing gastrointestinal parasites in wild two- and three-fingered sloths across both urban and primary forest habitats in Costa Rica. Read More…
Climate Change Threatens the Future of Sloths | 2024
Our research, “Sloth metabolism may make survival untenable under climate change scenarios,” led by Dr. Cliffe, has been published in PeerJ and explores a possible future for sloths and their survival in a world that is getting hotter. Read More…
The behaviour and activity budgets of two sympatric sloths; Bradypus variegatus and Choloepus hoffmanni | 2023
We used micro data loggers to continuously record, for the first time, the behavior of both Bradypus and Choloepus sloths over periods of days to weeks. We investigate how fluctuations in the environmental conditions affect the activity of sloths. Read More…
Myology of the pelvic limb of the brown-throated three-toed sloth (Bradypus variegatus) | 2022
Tree sloths rely on their limb flexors for bodyweight support and joint stability during suspensory locomotion and posture. This study aims to describe the myology of three-toed sloths and identify limb muscle traits that indicate modification for suspensorial habit. Read More…
Sloth genetics: a surprising twist | 2020
We collected hair samples from 98 two-fingered sloths (Choloepus hoffmanni) that originated from different regions throughout Costa Rica and used microsatellite analysis to look at the population genetics. Read More…
The sloths’ extraordinary metabolic response to temperature! | 2018
We determined the resting metabolic rate (RMR) of 8 adult three-fingered sloths (B. variegatus) using indirect calorimetry (i.e. by monitoring the oxygen consumption and carbon dioxide production of sloths that were sleeping inside of a metabolic chamber in Costa Rica). Read More…
Cheap labor: myosin fiber type expression and enzyme activity in the forelimb musculature of sloths |2018
We hypothesize that intrinsic muscle properties are also modified for fatigue resistance and predict a heterogeneous expression of slow/fast myosin heavy chain (MHC) fibers that utilize oxidative metabolic pathways for economic force production. Read More…
Hanging out for a drink | 2018
We photographed a male brown‐throated sloth (Bradypus variegatus) lapping water from the surface of a river in Costa Rica. Our latest work ‘Sloths hanging out for a drink’ has just been published in the scientific journal Frontiers in Ecology and the Environment.
Sloths Like It Hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus Variegatus) | 2015
During this study, we measured exact levels of food intake in three-fingered sloths and investigated how these levels were affected by changes in the ambient temperature. Read More…
Mitigating the Squash Effect: Sloths Breathe Easily Upside Down | 2014
We used ‘Daily Diary’ data loggers on both wild and captive sloths to determine the proportion of time spent inverted. Combining the hang-angle preference information with ventilation rate data, we use an energetics-based model… Read More…
Ongoing research
The Urban Sloth Project:
This long-term project aims to compare the behavior and activity of wild sloths living in highly urbanized areas with sloths living in healthier environments (protected primary and secondary rainforests). Read More…
Monitoring wildlife bridge usage:
We have installed almost 200 Sloth Crossing wildlife bridges in the South Caribbean of Costa Rica to help sloths and other species navigate between habitat fragments safely. We are conducting long-term monitoring of the bridges using motion-activated camera traps combined with automatic intelligence software.
The Great Sloth Census with Scat Detection Dogs
One of the biggest problems for sloth conservation is the lack of information about the status, distribution, and decline of wild populations. There are no official population counts and population trends are unknown. Read More…
Ecology of Maned sloths:
We are working with Professor Gastón Giné in Brazil and provided 10 special GPS backpacks for research on the endangered maned sloth (Bradypus torquatus). This current research project is conducted in the Sapiranga Reserve, Praia do Forte, Bahia. Read More…
Thermal Imaging Drones:
We are testing the detectability of sloths using specialized thermal imaging drones combined with artificial intelligence to automatically identify the thermal fingerprint of sloths. To do this, we are working in collaboration with researchers from Liverpool John Moores University and Koala experts from the University of Newcastle in Australia.
