Tackling the two-fingered sloth

28 Jan

Since beginning the Sloth Backpack Project in 2013, I have been desperately trying to tag a wild two-fingered sloth – but a combination of equipment failures, injuries and escapee-sloths stood in my way. I finally managed to do this in November, although it was no easy task!


I first spotted her hanging out in a large Sangrillo tree located just across the lagoon that runs in front of the sanctuary. This tree is surrounded by low down foliage, and so I knew she would have to climb down to within ‘grabbing’ height when she wanted to change trees. Unfortunately, I didn’t know how long this would take: two-fingered sloths love to eat Sangrillo leaves so she could happily stay there for days, and their movements are primarily nocturnal, so when she decided to move it would probably be during the night. Furthermore, two-fingered sloths are not as easy to catch as their three-fingered cousins; they are bigger, faster, stronger and have large teeth capable of inflicting a nasty bite. Basically, you don’t want to try and catch one of these if you are unprepared – they are surprisingly capable of defending themselves. To minimise stress on the animal and to ensure our safety, she would need to be sedated before I could tag her. I was fully expecting a long wait before I would have the opportunity to catch her, but as ever, sloths like to surprise us.


To my shock (and horror) I glanced at the tree just 2 minutes after first spotting her, and she had completely disappeared. She must have come down. I couldn’t miss this opportunity to catch her, and so I quite literally ran through the jungle, across the lagoon and to the base of the tree – but I couldn’t see her anywhere. She had vanished. I knew that she couldn’t be far away, so I began a process of frantically searching the surrounding vegetation for any sign of a sloth. After half an hour of wondering how she could possibly have disappeared so quickly, I spotted a ball of brown hair curled in a coconut tree overhanging the lagoon. She was above head height, but thankfully within climbing reach. I had learnt from previous experiences not to attempt catching her alone, and so I called the sanctuary handyman Donald and veterinarian Francisco. They turned up well equipped – with ladders, machetes, gloves, a stuffed bear and a syringe full of anesthesia Of course, you will probably wonder how hard it could possibly be for three adults to catch a sloth with all of this equipment, but it’s safe to say that chaos ensued.



As Donald climbed upwards on the thin branches, she panicked and began making her escape (surprisingly quickly) – across the lagoon. There were some very flimsy branches traversing the water, and she took her chance. Donald followed in hot pursuit, clutching the stuffed bear under his arm, but the tree just wouldn’t support his weight. Balancing over the water, he called for backup and a boatman quickly arrived in a canoe. By now, the sloth was fairly high up, still over the lagoon, resting on some vines. Never one to give up, we cut a large forked branch and, whilst balancing in the canoe, Donald used it to hook the vines and pull them (and the sloth downwards). This worked surprisingly well, until she panicked and began moving as fast as she could down the branch towards his face (this can only really be described as a ‘charging’ sloth). There was an incredibly frantic 30 seconds that followed, but somehow Donald managed to inject the anesthesia and avoid being bitten or falling into the lagoon. We then had a 3 minute window before the sedative kicked in, during which time she made her way as high up the tree as possible before falling asleep. Thankfully, her tree of choice was fairly climbable for a determined human. We finally had her!



Within a few hours, I had her harness sewn, her backpack sealed and the tags activated. This particular backpack was sponsored by the wildlife and conservation news network Earth Touch. I have been writing a blog for Earth Touch called Slothcentric for a while now, and the lovely people at the network were delighted to hear that their backpack would be the first to be deployed on a wild two-fingered sloth. To thank Earth Touch for their support, I offered them the chance to name this feisty female – and they decided on Becket (a great combination between Becky and Earth Touch).



We released Becket in the same Sangrillo tree that I had first spotted her in, but she didn’t hang around for long. By the following day she had crossed over the lagoon and was at the top of a huge tree, far inside the forest. I have been tracking her ever since, and I am beginning to piece together her activity patterns. As it turns out, Becket is a sloth that we were already very familiar with – she has been a regular visitor to the trees around the sanctuary for years. We used to frequently see a wild two-fingered sloth in one of the big almond trees across the river, and one day we noticed she had a tiny baby. We watched her over the course of a year as that baby grew and gained independence. That was Becket and her baby. I often still see them both in the same almond tree, and I am hoping to soon tag her fully grown baby – it will be interesting to see how their home-ranges differ! In the meantime, I am still trying to recapture Becket to change the batteries on her backpack and download the data – hopefully it will be easier than the first time!

7 8
Posted in: General
Share this post: