Live trafficking of primates such as gorillas, lemurs, orangutans, and chimps is part of a global multibillion-dollar trade that exploits the vulnerable and disadvantaged. Face Recognition can help us reduce this exploitation.

Primates have become a commodity, despite being some of the most endangered, intellectual, and sensitive animals on the planet. A series of frightening investigations from international specialists, UN agencies, conservation organizations, and media sources have exposed several incidents of systematic illicit trafficking and trade of gorillas, bonobos, monkeys, chimps, and lemurs around the world in the last decade.



The International Union for Conservation of Nature (IUCN) published a comprehensive assessment, Red List of Threatened Species, in 2008, concluding that world diversity is in grave danger. The IUCN discovered that 22% of all mammal species are ‘critically endangered,’ ‘endangered,’ or ‘vulnerable,’ according the organization. Primates are a particularly endangered animal order, with 60 percent of all monkey species and 91 percent of all lemur species facing extinction. Lemurs are only found on the island of Madagascar, where their forest habitat is being destroyed to make way for farms and to support the illicit hardwood trade. Overhunting also affects lemurs, whose flesh is greatly sought after. In the same way, the endangered golden monkey has lost a lot of habitats.


To cease and reverse the population reductions of endangered primates, intervention is required. Several studies on how to save these endangered primates using individual identifying methods like collaring (see Figure 1) and manual identification have shown benefits and drawbacks. Animals are captured and unique combinations of colored GPS collars and tags are placed around their necks, which is intrusive and poses a hazard to the animals. The procedure, however, allows for the gathering of data that would otherwise be impossible to get (e.g., blood samples, ectoparasites), but it is costly and inconvenient to utilize. These tactics have proven to generate acute stress reactions and have influenced group dynamics and reproduction in other vertebrate species.


Individual identification is non-invasive, but it requires extensive training, is difficult to collaborate with, and is prone to mistakes. Individualization of these animals by computerized face recognition is one such strategy. Improved identification and tracking will help these species’ long-term health and stability in several ways, including
(i) allowing for more efficient longitudinal studies,
(ii) removing the detrimental consequences of old tracking systems, and
(iii) preventing illicit trafficking and trade.



A non-invasive, rapid, and robust method of automatic primate individual identification is needed. Ideally, the automatic face recognition system should be deployed as a smartphone application for rapid deployment and use.

This automatic facial recognition technology was first developed by researchers at Michigan State University and might help conserve endangered primates such as golden monkeys, chimps, and lemurs. Many animals have distinct facial traits, for example, hair (pelage patterns), that make them suitable candidates for matching via customized face recognition algorithms.


Research shows that utilizing prevailing face recognition systems meant for humans is not sufficient. With further customization, we developed a custom primate face detection system that can identify a primate’s face in a given photograph and automatically crop and align (see Figure 2).




Following alignment, our in-house primate matcher can extract robust and efficient face representations for individualizing each primate. LENS’ primate face recognition system

(i) achieves state-of-the-art accuracy in individualizing lemurs, chimpanzees, and golden monkeys,
(ii) performs extremely fast inference,
(iii) takes a few mere megabytes for storage.
Therefore, our solution is perfectly suited for embedded devices such as smartphones.
Inspired by PrimID, we are working towards deploying a smartphone app that uses primate facial recognition to track endangered species and individuals through time with minimum effect. Users may upload a photo of a primate and check the database to see to whom it belongs. They may also examine the resemblance of multiple photographs to determine whether they belong to the same individual. It will be open-sourced, and available for free download on low-power smart mobile devices and would work without the internet.



Tens of thousands of primates have been seized or slaughtered with unspeakable acts of violence being inflicted on them in an illegal worldwide trade that has pushed certain vulnerable species to the brink of extinction. As primate species are threatened by habitat loss, hunting, and trafficking, primate researchers and conservationists must have efficient and effective tools to reliably and safely monitor these animals. Our primate face recognition system can greatly aid in these efforts to ensure that these endangered animals are protected. Through our collaborations with domain experts and field researchers, we plan to (i) enlarge our primate datasets applicable to multiple primate species, (ii) further improve the recognition accuracy, and (iii) keep all software open-sourced.

As primate species are regularly threatened by habitat loss, hunting, and trafficking, we at LENS are continuously combating illegal wildlife trafficking and trade by building efficient and effective tools to reliably and safely monitor our ancestral species.


Bewildered and terrified, these animals are employed for human amusement. They are often beaten or drugged into submission and used for entertainment like banging drums, dancing, and somersaulting to entice an audience. Zookeepers often beat them with sticks to get them to perform tricks. Many are given alcohol/muscle relaxants to make them easier to handle. Some are trained to guzzle alcohol and smoke cigarettes. Even if these animals are rescued – it’s difficult to reintroduce them into the wild. They, like people, suffer from withdrawal symptoms and require extensive rehabilitation. It is quite common to come across such performances ourselves in daily life, where one might see a monkey being made to dance, walk on a tightrope and provide comic relief.

Primates are also poached for their meat, sold for mere dollars, and body parts are used for traditional practices and medicine. Poachers also often wipe out entire clans to get their hands on an infant, which is much simpler to smuggle. It is critical to be aware of the maltreatment that these creatures endure. It is our role to bring light and raise awareness about this issue so that regulations are set into place to prevent heinous acts from being enacted against these mistreated animals. Primates are not playthings.