How global warming and climate change will affect sloths? 

How global warming and climate change will affect sloths?

Dr. Cliffe’s research from 2018 determining the metabolic rate of three-fingered sloths was utilized by a team of researchers based in Brazil, working to conserve sloths in the Amazon and Atlantic Forests of Brazil. Dr. Cliffe’s data was modeled against climate change predictions, and data from different ecologists quantifying and predicting current and future land cover and land use in the Amazon and Atlantic Forests were also used.

This paper is truly an amalgamation of many different people and organizations’ work used to draw hypotheses and conclusions about the future of wild sloths.

sloth drinking water
Are sloths drinking more water due to global warming?  / Photo: Suzi Eszterhas


The vulnerability to climate change

The paper, Integrating climate, ecophysiology, and forest cover to estimate the vulnerability of sloths to climate change is a great example of how to draw predictions from data without taking raw data out of context.

When all data is compiled together to give a broad, well-informed view of the situation, more reliable and accurate results can be produced. For example, only taking climate change into account, the conditions in some areas would become climatically suitable for the Maned Sloth to live in. What this data modeling doesn’t tell you is that with the rate of land use change occurring, those areas are likely to be deforested, and therefore uninhabitable for the Maned Sloth despite appropriate climate conditions.


maned sloth brazil
Maned Sooth (Bradypus torquatus) at Reserva Sapiranga


The research also shows how modeling the metabolic rate and behavior of the average mammal against climate change data gives entirely different results than using data specific to sloths. Sloths are extremely specific animals – they are poikilotherms, exclusively arboreal, and record-breakingly slow movers.

However, while multiple variables are modeled in this study, there are still many factors not taken into account which can result in variation of the given results. The inclusion of every possible variable into a model is currently too complex to produce readable results.


The results:

The results of this study are represented by the predicted net gain or loss of livable habitat for each species. Despite having similar lifestyles, each species produced different results.

Brown-throated sloths (B. variegatus) – Amazon rainforest

Photo: Suzi Eszterhas

These sloths produced the most promising results by a large margin. Taking global warming and changes in land use into account, a 174% habitat net gain is predicted. It is important to note that this species of sloth is considered to be the most populous and widely distributed of the three sloths considered in this study.

Pale-throated sloths (B. tridactylus) – Amazon rainforest

Pale-throated sloth Bradypus tridactylus. Sloth Island, Guyana. Photo: Suzi Eszterhas

These sloths produced the most concerning results of the three species. A 65% net loss of habitat is predicted. Despite encouraging predictions in a reduction of deforestation of the Amazon, climate change is predicted to cause these areas to become uninhabitable for sloths due to decreased rainfall. However, these animals are still considered ‘least concern’ by IUCN.

Maned sloths (B. torquatus)  – Atlantic forest

maned sloth brazil
Photo: Cecilia Pamich


A 7% net loss of habitat is predicted for this species. The Atlantic forest which the Maned sloth inhabits has already lost over 70% of its trees, so while this is the smallest margin found in the study, it is a detrimental loss for the habitat and species living within it. Loss of habitat is the main reason the maned sloth was given ‘Vulnerable’ status by IUCN, and this study has determined that the maned sloth is the most affected by climate change in comparison to the brown-throated sloth and the yellow-throated sloth.


Reforestation and forest conservation against global warming

The study predicts that adequate reforestation occurring on the outskirts of their current regions will likely result in a greater distribution of these animals, especially in the case of the maned sloths in the Atlantic Forest of Brazil as the climatic conditions will be favorable due to Global warming. Currently, the Atlantic Forest has been reduced to less than 30% of its original size, therefore reforestation is predicted to be the most effective conservation strategy for this area.


maned sloth distribuition
Maned Sloth Distribuition / Image: Instituto Tamandua


While the Amazon Rainforest still holds over 80% of its trees, it’s predicted that climate change will transform this damp, neotropical climate into a much drier and sparser habitat, which is entirely unsuitable for sloths, as well as many other rainforest species.

The research clarifies that the dispersal rate (the rate at which sloth populations are able to inhabit previously uninhabited areas) is overestimated, due to sloths’ low reproductive rates.

This study helps to determine whether reforestation and conservation of already standing forests are the best courses of action in order to conserve these already vulnerable sloths – they are!


-Amelia Symeou

Ecology Coordinator

A Little Taste of Heaven: Tracking Diaries #8

A Little Taste of Heaven: Tracking Diaries #8

I’m standing amongst the wreckage of felled trees and bulldozed undergrowth, my boots crunching on dead vegetation, but I’m not looking down.

I’m looking up. I’ve heard from Sarah that Luna has a new baby, just days old, and I haven’t seen her yet.

I haven’t seen much of sloths lately, it feels like. Between my other duties over the holidays and a couple of Covid scares I’ve become a little too intimately familiar with the view from my desk, the exact number of dead pixels on my computer screen, and the utter indolence of my cats, who literally do nothing other than sleep and demand food.

It feels a bit disorienting to be out in the field again. The last time I was this deep in Luna’s territory, it had more trees and less gravel, before some jerk came and tried to pave the place over. I watched from the other side of my phone screen as SloCo came to the rescue and notified the appropriate authorities of that transgression, and cheered through my coughing fits as my the community saved the remaining trees from the heavy equipment and sweated through a blistering hot day to put up fence posts to keep the tourists’ cars from finishing what the bulldozers had started.



It was in the dead branches of some of her former trees that Sarah found Luna and her new baby, trying to crawl to a safe haven through the twisted roots and twigs and spiders. Sarah reported that Luna arrived in her new tree safely, and it is now my job to figure out what the heck tree that actually was.



Our tracking equipment is being even weirder than usual. According to our radio receiver, Luna has in fact boarded a raft and is bound for—a quick check of Google maps—Aruba. It’s possible that the jungle has rusted some secret but essential piece of electronics deep inside the receiver, or that I’ve forgotten how to track sloths, or maybe that the antenna is possessed by demons.

(Note so self, Google “how to do an exorcism” when I get home. Don’t tell my boss.)

I’m still fiddling with the equipment when I have one of those perfect sloth tracking moments: I just happen to look up at a movement out of the corner of my eye and catch a slow-moving silhouette on the side of the guarumo tree. Quick as a cat, I whip out my binoculars, and then fist punches the air as I spot a three-fingered female with an itty bitty little replica of herself clinging to her fur. Another minute confirms the radio collar on her neck—this is definitely Luna!



The receiver is still insisting that Luna is somewhere out on the Caribbean waves, so I turn it off and instead pull out my phone, snap a few pictures, and then settle in for a good look at her.

Baby sloths are cute on a level that maybe ought not to be legal. They almost don’t look real; they’re just arms and eyes and fuzzy cuddles incarnate, like the living manifestation of a hug.

By now a crowd has gathered around me to marvel at the sloths. Luna has settled onto the branch she was after and gone to sleep. Watching them, I have to smile. Luna’s territory will take a long time to regrow, but here in front of me is proof that new life, and new growth, is always possible. We have named the baby Celeste, which means “heavenly”. It is also the Spanish word for the color of a clear sky in the daytime.

If you want a little taste of heaven, sometimes all you have to do is look up.

-Ames Reeder

The community of Puerto Viejo came together to stop habitat loss

The community of Puerto Viejo came together to stop habitat loss

Over the last few weekends of December 2021, we and our sloth guardians in Puerto Viejo witnessed deforestation occurring in the Maritime-Terrestrial Zone (MTZ) of the South Caribbean – specifically between Selina Hostel and the Cocles viewpoint.

This spot may sound familiar, as it is the home of one of our Urban Sloths Luna and her big baby Sol. The MTZ is a 200m strip of public land along the coastline that is strictly regulated by the government; building, exploiting flora and fauna (which is what was occurring here), entrances from the road, etc, is only possible with the correct permits, which are very difficult to obtain. 


baby sloth luna sol


  • Read More: The Urban Sloth Project


This destruction began slowly on Saturday 11th December 2021 which rang alarm bells; as we all know, most government employees do not work on the weekends. There was no official government body to oversee the ‘pruning’ of low growing vegetation and undergrowth, as well as the felling of some healthy trees.




We thought that was the end of it, as the undergrowth is cut back periodically for security purposes along the beach path. 

The situation becomes worse

However, on Saturday 18th December 2021, the South Caribbean community awoke to a greatly concerning scene. The destruction had intensified, now with more chainsaws to cut more healthy trees and driven hydraulic machinery to level the ground and fill it with gravel. 




The community came together in outrage, including many influential members of the community, and reported these works to the authorities, specifically to the Public Force and SINAC. Hours later, SINAC responded, went to the site, and put a stop to the work when they found flagrant dismissal of MTZ regulations. 



A formal report was drawn up and sent to the Bribrí Prosecutor’s Office for alleged violations of various environmental and land-use legislation in Costa Rica.

These actions caused a serious environmental impact in that area, which is considered a Natural Heritage of the State and part of the MTZ.



A gloomy picture

On 20th December 2021, SloCo staff visited the site to assess the extent of the damage. We found 15 sloths of both families crammed into the few remaining trees, all demonstrating abnormal behaviors. 



The sloths were very active. Multiple sloths were coming to the ground to fruitlessly search for another appropriate tree and attempting to cross the busy road because all tree connections were lost. 


A SINAC officer helping one of the sloths


Sloths are creatures of habit and these guys had just had their entire home destroyed – they were in great distress. We spotted Luna among them, sharing a guarumo tree with other sloths.


En esta imagen se puede aprecira sutilmente la antena del collar de Luna.

Development without destruction

We understand that in some cases certain types of public works may be necessary; however, all these must be carried out in strict adherence to the law, having carried out the associated environmental impact studies, and above all with an entire and great understanding of the ecosystem being interfered with.

In the last two years, we have seen a huge increase in construction in the South Caribbean, which is rapidly eliminating the coastal and inland ecosystems of Talamanca.

Unfortunately, the lack of intelligent planning and environmental awareness results in excessive systemic pressure on flora and fauna. These species will sadly pay the ultimate price for human intervention and destruction.