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.