Meet the Monkeys: O Group

I am going to take you back in time a little bit to introduce to O Group and share with you how we got to know them. Individual identification of non-sexually dimorphic, arboreal primates like capuchins can be extremely difficult, especially when they are only partially habituated to humans. They are incredibly fast, never stop moving and spend a lot of their time high in the forest canopy. It is impossible to tell how many individuals there actually are when you find a group. You see maybe three or four but the trees all around you rustle and squeak and you know there are more monkeys watching you that you can’t see! Very frustrating.

The boys trying to show me who's boss back in June 2014.

So we decided to try something different. In 2014 we built two feeding platforms in the Atlantic Forest, one in the centre of F Groups range and one in the centre of O Groups range. The original purpose of these platforms was to let the monkeys learn that tasty treats were available on a semi-regular basis so that we could eventually capture some individuals and fit them with radio collars.  To make sure that the food was being taken by monkeys we set up camera traps (there are all sorts of creatures in that forest that are more than happy to steal corn including coatis, tayras and plush crested jays!). In July and August 2015, amazing monkey volunteer Emily Briggs and I carried out intensive baiting, refilling the tables with corn and bananas every three or four days. The HD videos of the monkeys that the cameras provided allowed us to finally individually identify the members of O Group. We watched the 196 videos of monkeys frame-by-frame and identified the monkeys based on different physical characteristics including body size; shape, size and colour of tufts; shape of the black cap on the forehead; shape and colouration of facial masks and distinctive scars or wounds. If we got a clear shot of the genitalia we could also assign a sex.

 We identified 18 individuals: 3 adult males (AM), 5 adult females (AF), 5 subadults (SA), 4 juveniles (JUV) and 1 infant.

Damien, the dominant male, was the first monkey I was ever able to identify and his belligerent temperament and enormous size made him a firm favourite of both the volunteers who helped out on the project and myself. Hades, the second-in-command always seemed to be in a foul mood, quick to threaten and throw branches at observers. In March 2016 we captured and fitted Hades with a VHF collar. Bev appeared to be the dominant female, even though she is the smallest. Alien is definitely the most curious of the adult females and is often first to come down and investigate observers. She has been known to try and urinate on people so it is often sensible to move away when she gets too close!

This study provided the first detailed information on group demographics of Sapajus cay in Paraguay and has been accepted for publication in the journal Neotropical Primates. Watch this space for more information about when the paper will be available!

Within the last month, things have changed. In August 2016 a new group was spotted in the South Atlantic Forest, right in the centre of O Group’s territory. Damien has been missing for over a month and while he may have moved to the new group, we are assuming that he has died. It looks as though Hades has taken up the mantle of dominant male and a new adult male we have named Macho has been spotted hanging around very close to O Group. Hopefully over the next few months we will get some insight into the power struggles happening within O Group and between them and new group. I am willing to bet that Trump Vs. Clinton has got nothing on the drama playing out in our Atlantic Forest right now! 

Hades today with his battle scars.

So Paraguay, what do you have to offer?

When it comes to primatology, Paraguay has been pretty left behind. The last studies were carried out in the 1980’s and early 1990’s by Jody Stallings and Patricia Wright and since then behavioural studies of Paraguay’s primates have been non-existent. I think that part of the reason that Paraguay has been overlooked is that is does have a much lower diversity of primate species that other South American countries. At the last count there were 156 primate species in the Neotropics (and more than 204 when sub-species are included) (Mittermier & Wilson, 2013) and this number is still rising as new species are discovered. Of this huge number of species, only 5 are found in Paraguay. But I do not believe that this makes them unworthy of the efforts of conservationists!

My research, and therefore one of the main focuses of this blog, is the behaviour and conservation of the hooded capuchin, by far the most well known monkey in the country. So in this post I will focus on Paraguay’s other 4 primate species.

Arguably the second most well known monkey in Paraguay is Alouatta caraya. The Black-and-Gold howler monkey, or the Caraya to the locals. This species is sexually dimorphic, the males are black and the females yellow. They are very widespread, not only found all over Paraguay but in some states of Argentina, Brazil and Bolivia. Howler monkeys are the only New World primates that eat a lot of mature leaves in their diet and as a result can spend up to 70% of their days resting. The howler monkeys have a highly specialised enlarged voice box and hyoid bone that allows them to produce the loud roars that they are famous for. These howling sessions involve the whole group and can be heard up to 2km away!

Now we visit the primates of the Chaco. The Gran Chaco that makes up the northern half of Paraguay is a vast dry prickly forest with salt-water lakes and extreme heat. This amazing and unique place, one of the last truly wild places on earth, is the fastest disappearing habitat in South America. Let’s meet the tough little primates that call this weird and wonderful place home.

First, Aotus azarae: Azara’s owl monkey. This species of owl monkey is found in Argentina, Brazil, Bolivia, Peru and Paraguay. The genus Aotus are the only nocturnal monkeys. However, in the Chaco of Argentina and the Gran Chaco of Paraguay the behaviour of this species is rather unusual. Instead of being nocturnal they are cathemeral (meaning they are active during the day and night). This species lives in monogamous pairs with their offspring and some adults range alone (possibly subadults that have left their natal group or older adults searching for a new group following an eviction) (Fernandez-Duque & Huntington, 2002; Fernandez-Duque, 2004). In Paraguay the popularity of this species as a pet is increasing, as it is believed to be less aggressive than the capuchins.

Photo Credit: Sjeff Ollers (www.faunaparaguay.com)

Up next, the black-tailed marmoset, Mico melanurus. This is the smallest of Paraguay’s primates. Stallings (1985) recorded this species in the far north-east of the Chaco in the national park Defensores del Chaco. It isn’t just the small size of the marmosets and tamarins that set them apart from the other New World primates. These little creatures have modified claws rather than nails on all digits except their big toes. This is a big difference when you consider that having flat nails instead of claws is a typical characteristic of the Order Primates. Another big difference is the occurrence of twin births. Other primates species can have twins but it is not common, whereas the marmosets and tamarins regularly have twin infants.

Photo Credit: Paul Smith (www.faunaparaguay.com)

Last but not least Callicebus pallescens, the pale-mantled or dusky titi monkey. This species is found in the Chaco of Bolivia and Paraguay and the Pantanal wetlands of Brazil. In Paraguay it is found in the xeric forests of the north and swamplands, gallery and palm forest in the south (Stallings, 1985). Titi monkeys form small, pair-bonded groups that are believed to be monogamous. They eat fruit and seeds and weigh between 800 and 1300g.

Photo Credit: Jon Hall (www.faunaparaguay.com)

This is a very brief introduction to Paraguay’s non-capuchin primates. All of these species are classified as Least Concern by the IUCN, partly because of their large ranges, but populations of them all are decreasing. The situation in Paraguay is dire. The Atlantic Forest has been almost completely destroyed; the Cerrado is vanishing beneath the hooves of cattle and plantations of invasive eucalyptus and the relentless march of the soybean monocultures and cattle farms has reached the Gran Chaco. With such little information available regarding wildlife populations in Paraguay it is almost impossible to know whether or not these monkeys are endangered in the country. I believe it goes without saying that if nothing is done to curb the rampant deforestation in all of Paraguay’s habitats, we are going to see more names appearing on the endangered species lists not long from now.

Primatology in Paraguay…Really?

Are you in to primates? Do monkeys fascinate you? Whether you are interested in primatology (the study of primates) or just really like watching monkeys smash nuts on David Attenborough programmes, Paraguay probably isn’t a country that springs to the forefront of your mind when you think about where wild primates might live. And honestly, I don’t blame you.

Paraguay is a small country nestled right in the heart of South America. Paraguay isn’t just overlooked by tourists. In terms of the biological sciences and conservation it is miles behind its neighbouring giants of Brazil and Argentina. This is a serious problem in a country that has destroyed 97% of its humid Atlantic Forest in the last 50 years and who's Gran Chaco forest is disappearing at an alarming rate (more than 53,000ha was destroyed in December 2014 alone and that has not slowed down!). Conservation works best when it is based on a foundation of strong research. And this foundation was sorely lacking in a country so desperately in need of conservation efforts.

Enter Fundación Para La Tierra.

Scottish geneticist, Karina Atkinson (check her out, she’s amazing! www.rolexawards.com/profiles/young_laureates/karina_atkinson), started this small NGO based in a tiny private reserve on the shore of Paraguay’s only spring-fed lake, Laguna Blanca, in 2010. The organisation works to protect Paraguay’s disappearing natural habitats through a combination of scientific research, education and community engagement and it the only organisation in Paraguay conducting year-round scientific research. I came out from Edinburgh, Scotland, to join Team PLT in January 2013, as what as since turned out to be pretty much the only primatologist in the country. My job: to habituate and study the reserves population of hooded capuchins (Sapajus cay).

Habituation is NOT an easy process, particularly with primates as long-lived and intelligent as capuchin monkeys. For what seemed like an eternity, my hours searching through the spiky, mosquito-filled Atlantic Forest would be rewarded by no more than an almighty crash and, IF I was lucky, that flash of a furry black tail as the capuchins retreated far faster than I could chase them! But nothing good comes easy and now the Atlantic Forest fragment of Laguna Blanca is home to two groups of semi-habituated monkeys (they still threaten me but do let me hang out with them!) and one new group only discovered in August 2016.

Along with my amazing job with PLT, I am in the early days of my PhD in Conservation Science with the University of Aberdeen. My PhD research will focus on my monkey groups here at Laguna Blanca, studying their social and ranging behaviours, genetic viability and parasite loads in order to determine whether this population will be viable in the long-term. If such a small population of capuchins can survive in such a small fragment of forest, that is good news for Paraguay’s Upper Paraná Atlantic Forest which (outside of two larger areas) only remains as small islands in a sea of soy fields and cattle ranches.

My goal with this blog is to share with you what life is like as a field primatologist in Paraguay and to spread the word about conservation in this amazing, forgotten corner of the world.

Enjoy!