Sri Lanka is my home. I and my family live in the tropical rainforests of Colombo, located in southwest Sri Lanka and is the country’s most populated city. I have relatives across Sri Lanka as well. Some found home in North, North Central, and Eastern part, while the other members preferred to stay in mountain altitudes. Well, others could say that our place is kind of different from where my other relatives are. Our place is called a “wet zone”, because among all the islands around us, we are the only region who receives an annual rainfall twice than usual (New England Primate Conservancy, n.
d.). We may have different preferences in where we want to stay, but one things common: we often choose places where there are a near source of permanent water (Dilmah Conservation, n.d.).
According to Dilmah Conservation (n.d.), generally, the color of our coat in our body and limbs is brownish-black, while our whiskers varies from white to pale brown.
Though for newborns this is not the case; in fact, it is the opposite. If we have brownish-black coat, they have a pale grey one with an additional touch of brown in their crown, arms, legs, and chest. Also, contrary to most beliefs, we actually have a brown face not a purple one. But if you ask me what makes my family different from my relatives, I would say that we are lighter and more gray-brown than the others, and our rump patch is actually in the spectrum of silvery gray.
Our forearms and shanks are nearly black in color, while our crown and nape are pale brown. I also think that one of our big differences is that my family’s tail is slightly tufted at the tip. To introduce myself better, as stated in New England Primate Conservancy ( n.d.), our head to toe measurement varies from 44.7 cm to 67.3 cm; our tails, on the other hand, could reach 85.1 cm, which is still bigger than our head to toe range. As a whole, other than our weights, we have limited means of checking if someone is a male or a female. Usually males from our family and relatives weigh 8.5 kg, while the females has a weight of 7.8 kg. As for our diet, like most Old World monkeys, we also have a sacculated stomachs, which helps us in breaking down plant material (New England Primate Conservancy, n.d.). So from that, one could assume that most of our diet consists of leaves, making us folivorous, alongside fruits and flowers. Fruits like jackfruit, coconuts, and mangoes are the ones we enjoy eating the most. Well, some people say that we have been observed eating soil from termite mounds. In our defense, we eat soil from that mounds because in contains minerals that helps us not only in digestion, but also in helping us defend ourselves against toxins. I am both arboreal and diurnal. That means I am physically adapted to live in trees; and that I am most active and productive during hours where we could see the sun. Most people say that I am a shy animal, which is actually true, and that makes it hard for people to know more about me and my relatives.
Let me also tell you about our grouping system and how each group’s dynamics work (New England Primate Conservancy, n.d.). First, the one-male unit consists of 14 members only. This 14 include: one dominant adult male, his harem of about 7 adult females, and their offspring. Commonly, territories of groups are not meant to overlap, but because of some events, some groups are forced to share their territories to each other. Then we have the all-male groups or the wanderers. Contrary to one-male unit’s 7 adult females, the wanderers only have 1 to 3 females in their group, and these females don’t mate with the males in their group. Their dynamic is quite different: they hunt and spend most of their time alone, but when it is already time to sleep, they all meet in one sleeping location. Lastly, there’s the two-male units wherein the second will serve as the backup in case there are territorial conflicts with other groups; giving protection to the offspring. That change in the grouping system happened because with our habitats gradually diminishing in size, bringing one group more in contact with another: territorial disputes could happen. And these disputes are not your ordinary one, these ones could lead to infanticide of offspring. With our environment rapidly changing, we too should adapt to for us to be able to survive.
Maybe you are wondering, and you’ve been wanting to ask me this question: why is your habitat dwindling? New England Primate Conservancy (n.d.) stated that it all began when our home country, Sri Lanka, got out of its 26 years’ worth of civil war, and with our country becoming one of the faster growing economies in the world and wanting to prosper more as a nation, to make room for new infrastructures, the people around us ended up cutting more trees than what is needed—including our habitats. Due to several decades of deforestation (Hill, 1934, as cited in “A Survey of Sri Lanka\'s Endangered and Endemic”, 2007), over 90% of the known range of our habitat now consists of commercial operations and other areas of human activity. This depleted our preferred habitat and principal sources of food. For arboreal and folivorous animals like us, who live our lives on trees and eating leaves, forest fragmentation is a major setback. Since we are not willing to cross roads and large patches of bare grounds, we tend to stay where we at. We see that fragment that we are in as an island, and when this pursues, there will eventually be less diversity because the gene flow is lacking. Thus, making us more prone and vulnerable to diseases. In addition, because of the loss of the trees that serve as our habitats, we are forced to live alongside humans. And sometimes, people capture us to raise as house pets. The probability also of us getting killed by vehicles and dogs is high. We also need to be careful when we climb onto power lines and electricity cables because it could also lead to our death. We are occasionally shot and killed while feeding in home gardens in some parts of its range (Dela, 2004, as cited in “A Survey of Sri Lanka\'s Endangered and Endemic”, 2007). Thus, deforestation indirectly leads to a wide range of human-induced fatalities. Molur et al. (2003, as cited in Trachypithecus vetulus, 2008) summarized the other treats to us. In includes: crop plantations, development, human settlement, deforestation, forest fragmentation, illegal trade for food, pylon collision, and habitat loss. Also as I mentioned earlier why explaining our group systems and dynamics, sometimes because there’s not enough land for the groups, there are territorial conflicts that may arise. And these conflicts are violent, leading to deaths of many. This goes to show that deforestation does not only affect reduction in our group size; it also affects the disruption of our social organization, loss of diversity in our diet, and our increased mortality.
But people are organizing and making sure that I and my family won’t be extinct. Molur et al. (2003, as cited in Trachypithecus vetulus, 2008), stated that there are ways to help us maintain our population. These are: habitat management, public education, limiting factor management, work in local communities, and a coordinated Species Management Program; and the following areas in need of research: genetics, taxonomy, life history, behavior, surveying, limiting factor research, epidemiology, and studies to identify viable method of conserving the subspecies. On the other hand, Kalatuwawa and Labugama, the two reservoirs that supplies water to 1.2 million inhabitants of Colombo and is found in the forest that inhabits most of us, represents the last and most secure strongholds for maintaining our specie. Also the Forest Department (Rudran, 2007), has indicated interest in replanting the pine plantations, with native species, found within these reservoirs. This will surely help us as it will increase our preferred habitat. But to continue this, they need to first study if it will fit dietary preferences in forested habitats. Forest Department also has plans to promote forest conservation and generate income for communities living around its forests through environmental education and ecotourism programs. This will not only benefit the local communities, but also create opportunities in promoting the conservation of our specie and our habitat. Rudran (2007) said that we could be used as a model in environmental education programs that will help disseminate information on the impacts of the destruction of our habitats to our survival.
In addition to that, most people that live within our range are Buddhists, and they have a strong aversion when it comes to killing animals. Rudran (2007) said that this taboo may explain why we have survived until to this day, considering that Colomba is a densely populated area, and we are viewed as pests and nuisance to the people.
Recent reports in Sri Lanka suggest a shift in human tolerance (Dela, 2004, Nahallage et al., 2008, as cited in “Habitat use by western purple-faced langurs”, 2010). But this shift may beworsen by the fact that we, as a whole, are showing greater tolerance towards humans, thus making us easy targets for catapults and rifles (Eschmann et al., 2008). But at the end of the day, it is evident that a broader understanding of the complex interactions that take place between us and humans living in sympatry is of paramount importance to the survival of our kind.
I am a Western Purple-faced Langur and the International Union for Conservation of Nature (IUCN) (2008, as cited in Trachypithecus vetulus, 2008) as one of the twenty-five critically endangered primate in the world.