Urban Sloth Project: the impacts of habitat disturbance

Urban Sloth Project: the impacts of habitat disturbance

The Urban Sloth Project is a long-term investigation into the impacts of habitat disturbance and rainforest urbanization on the behavior of wild sloths in Costa Rica.

Many people believe that Costa Rica is the best place in the world for seeing sloths – and for good reason; you are almost guaranteed to see a sloth if you visit this tiny Central American country!

Unfortunately, we suspect that this is a sign of a much bigger problem.


social distance sloths
A group of tourists keeping a proper distance from the sloth at Puerto Viejo de Talamanca, South Caribbean.


Sloths in healthy environments are hard to see

In an ideal situation sloths would live in primary rainforests, where the multi-story canopy interlocks and trees are shrouded in extensive epiphyte growth. In this environment, sloths are perfectly camouflaged and become practically invisible, hiding in the dense foliage at the top of gigantic trees.

Unfortunately, the remaining primary rainforests are dwindling as defirestation escalates, and sloths no longer have access to their preferred habitats. They are being forced to exist in increasingly urbanized environments, and here they cannot hide!


find the sloth


Sloths are slow-moving, habitual animals and are therefore very sensitive to changes in the environment. They are unable to run or jump to traverse gaps between trees, and so habitat fragmentation creates a lot of problems. While trying to navigate an increasingly urbanized world, sloths are being electrocuted on powerlines, attacked by dogs, hit by cars, and exploited by humans.


sloth problem
A sloth trying to navigate an increasinly urbanized world. Photo taken in the South Caribbean of Costa Rica. 


Sloths in Costa Rica are now considered to be of conservation concern due to habitat loss from agriculture, livestock production, and the increasing urbanization of the rainforest. In line with this, sloths are the most frequently admitted species to rescue centers in Costa Rica.


find the sloth
A healthy rainforest environemt and the sloths preferred habitat

A massive lack of information on wild sloth behavior

Such a lack of knowledge makes it very challenging for us to develop effective methods to conserve sloths – it is very difficult to protect something that you don’t know anything about!

For two-fingered sloths in particular, even basic data on the natural history and ecological requirements of the species is lacking. For example, information on the habitat preference, ranging patterns, population densities, diet, and reproductive behavior of this genus is incredibly scarce, and for some sloth species, is completely absent.


two fingered toed sloth
There is a massive lack of information on the ecology of wild two-fingered sloths


With current extinction rates indicating that we are in the midst of a sixth mass extinction, a lack of knowledge covering the basic ecological requirements of a species is of concern due to the profound implications for the development of future conservation strategies.

Monitoring 32 sloths

The Urban Sloth Project aims to compare the behavior and activity budgets of sloths living in highly urbanized areas with those sloths living in healthier environments (protected primary rainforests).

Over the next 5 years, we will be tracking and monitoring 32 sloths (16 three-fingered sloths, and 16 two-fingered sloths) using VHF radio collars and compact data loggers. The results will be used to develop effective conservation strategies that will help humans and sloths to peacefully coexist.


The data collected will help us to determine:

  • Amount of time spent active vs inactive.
  • Amount of time spent engaging in different behaviors.
  • Home range size.
  • Distance traveled per day.
  • Dietary preferences.
  • Amount of time spent traveling in the canopy vs traveling on the ground.
  • Circadian rhythm of activity – How sloth activity is impacted by the environmental conditions (temperature, humidity, wind speed, rainfall, moon phase).
sharon urban sloth
Sharon is the first sloth collared for the Urban Sloth Project. She was rescued on the side of a road while being harassed by a dog.

To protect sloths, we must first understand them

The knowledge we gain from this project will enable SloCo to make meaningful changes to the lives of sloths living in rapidly changing environments. For example, we will be able to identify which tree species are most important for sloths living in urban areas, and we can make sure that these species are protected and replenished.

We will also be able to identify areas where canopy connectivity needs to be improved to aid sloth dispersal via the installation of wildlife bridges and through targeted reforestation efforts.

You can follow The Urban Sloth Project through our social media platforms (Facebook, Instagram, or Youtube), and also by adopting Sharon, Croissant, and Cacao, where you will receive quarterly updates from our research team!

This project is only possible due to the generosity and kindness of our supporters – thank you for being a part of Team Sloth!


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