Sloth Science and Research

research (climate change scenario) 1

Sloth Science and Research

In order to develop and implement any good conservation strategy, a solid scientific knowledge of the sloth’s ecological requirements is necessary.

For this reason, we fund, coordinate, and publish high-quality research into many different aspects of sloth biology and ecology. Existing and ongoing research projects from the Sloth Conservation Foundation include:

Published Research

The behaviour and activity budgets of two sympatric sloths; Bradypus variegatus and Choloepus hoffmanni

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…

activity budget pattern sloth-min

Sloth genetics: a surprising twist

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…

sloth genetics costa rica

The sloths’ extraordinary metabolic response to temperature!

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…

NASA's ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) measures the temperature of plants when they run out of water, highlighting the stress of plants and detecting droughts

Sloths Like It Hot: ambient temperature modulates food intake in the brown-throated sloth (Bradypus Variegatus)

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…

sloth eat food digestion 3-min

Hanging out for a drink

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.

sloth drinking water

Mitigating the Squash Effect: Sloths Breathe Easily Upside Down

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…

sloth sleep

Myology of the pelvic limb of the brown-throated three-toed sloth (Bradypus variegatus)

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…

Brown-throated Three-toed Sloth 
Bradypus variegatus
Male (covered in algae) 
Aviarios Sloth Sanctuary, Costa Rica

Cheap labor: myosin fiber type expression and enzyme activity in the forelimb musculature of sloths.

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…

Brown-throated Three-toed Sloth 
Bradypus variegatus
Male (covered in algae) climbing down vine
Aviarios Sloth Sanctuary, Costa Rica

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…

sloth mother on a shelf

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. 

Kinkajou (Potos flavus) on bridge SC-143

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…

scat dog 4-min

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…

maned sloth

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.

rainforest emergent layer-min