Research

Over the last decade, my research has included both field and laboratory-based data collection, with the integration of technology to study both the behaviour and health of Amazonian wildlife. In the Peruvian Amazon, I manage a long-term mark-recapture program of saddleback (Leontocebus weddelli) and emperor (Saguinus imperator) tamarins. Most recently, this work has expanded to include community-level disease screening of birds, bats and small mammals. At a research site in India, I am also investigating molecular genetics-based biodiversity screening for rare mammals. Rather than focus on exporting samples from host countries for analysis in foreign laboratories, not a possibility for some protected species, my team has focused on local capacity building by installing the first molecular genetics field laboratory in Peru.  We hope to continue this work in India and other sites soon.

My research interests, in broad strokes, include:

Biodiversity Monitoring

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As forests become increasingly fragmented wildlife populations become isolated from each other and conservationists are faced with evaluating the viability of populations of threatened species to implement species survival plans. Such research is often only successful, however, for species at high population densities or for those that we can easily track. Time and again, cryptic or rare species are routinely missed in even the most comprehensive surveys. For example, my previous work analysed mammal surveys over 40 years and revealed that the small and cryptic Geoldi’s monkey (Callimico geoldi) is present in areas that have little or no protection, and missing from many protected areas.  Mostly, however, it is tough to survey on foot, and thus survey technology must adapt to be beneficial for such species, in a variety of habitats, regardless of the ease of tracking these animals in the wild.

In my research, I focus on using molecular tools as a solution to wildlife monitoring in situ, within the animal’s habitat.

Indirect Monitoring: My team are analysing the blood meals of leeches as a means to indirectly monitor biodiversity in the Western Ghats of India and Lawachara National Park in Bangladesh, using genomics to identify DNA barcodes for these species.

Community-Level Screening: In Peru, new mark-recapture programs implemented across birds, bats and small mammals allowed my team to sample from over 500 animals in 2018, belonging to a minimum of 100 different species. In the majority of cases, since we took no holotype specimens as museum vouchers, we only have the animal’s DNA to verify its taxonomic identity.

Obtaining biological samples from a broad group of animals is difficult, but once achieved, our obstacles do not end there. When many species surveyed are either data deficient or threatened, laws protect the transport of these samples outside of host countries (and rightfully so). My research team has recognised the inherent difficulty and has worked to process these samples directly within the Peruvian Amazon at a new facility we established together with the Inkaterra Association. We call it the Green Lab, the first molecular genetics field laboratory in the Amazon.

My primary interest today lies in the innovative use of portable field laboratories to address problems in situ that have been unavailable for study due to the threatened nature of the focal species involved.

The Sex-Health Paradox:

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As early as the mid-1700s, the first life history tables assembled for human populations indicated that females experienced greater longevity than males. Despite many population-specific features, this general pattern seems to hold true across many different human communities. The paradox, however, lies in the fact that men tend to report better health parameters than females, despite on average not living as long as women do.

Testing the sex-health paradox involves measuring longevity, senescence and health indicators, and has been successfully attempted in numerous studies of human populations. Among the nonhuman primates, however, this paradox has only been investigated in the baboons of Amboseli. The Amboseli dataset is incredibly rich – spanning 40 years of near-continuous observation and detailed health monitoring. And at Amboseli, despite every expectation that baboons too would display this paradox, it was found not to be supported.

Why would this occur with long-lived, savannah primates such as baboons who so closely resemble our earliest ancestors? What can we expect among the callitrichids, with their significant departures from the baboon pattern? They are female dominant, cooperatively breeding, shorter-lived and rainforest-dwelling primates. At Los Amigos, we are building the robust dataset that is required to ultimately answer these questions. Every year, we add another piece of the life history puzzle while monitoring health indicators across seventy animals, two species, and fourteen primate groups.

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To gain a better understanding of the physiology and health of wild primates, it is essential to be able to observe them up close. However, the capture-program at Los Amigos was initiated for reasons very far from these scientific aspirations. To put it quite simply, the Callitrichidae are notoriously homogenous in their appearance, making it virtually impossible to tell any adult from another in the group.  Males and females look alike, and to make things more difficult, they routinely give birth to infants who grow quickly into morphologically identical adults. Thus, the study of the behaviour of these fascinating primates is often restricted to group-level approaches.

To circumvent such problems associated with studying diminutive arboreal primates, we implemented a mark-recapture protocol in 2009. We began with the saddleback tamarins (Saguinus fuscicollis, now known as Leontocebus weddelli or Saguinus weddelli),  but soon incorporated emperor tamarins (Saguinus imperator) and titi monkeys (Callicebus brunneus) into the program. Today, our protocol for safely working with small arboreal primates has been published, and the detailed guide is available upon request for those with a scientific and noncommercial interest in working with these primates.

Although capture programs can and have been misused in the past for exploitative or even merely careless reasons, it is imperative not to keep protocols hidden from use. A good capture protocol can save lives and reduces unnecessary stress to animals. Thus, we are currently involved in soliciting and recording capture-and-release protocols used by primatologists and veterinarians on wild primate populations across the globe. For more information, or to participate in this program, please see here.