Evaluating wildlife diversity and habitat use in Colombia’s understudied and underdeveloped Orinoco Basin

Evaluation of Reptile, Amphibian, Bird, and Mammal Diversity and Habitat Use in the AKAE Reserve in Orinoquía, Vichada, Colombia

Edgar (TJ) Francisco

Located in the Orinoquía region, in the state of Vichada, the AKAE Conservancy is the largest conglomerate of private natural reserves in Colombia. A significantly understudied and underdeveloped region, the portion of the Orinoco River Basin in Vichada looks, from the front seat of a six-seater plane, like hundreds of scraggly veins of lush lowland rainforest coursing through an endless sea of grassland savanna. The forest veins, which are often no wider than a few hundred meters, enshroud the myriad streams which drain the landscape and all eventually flow into the Meta and then the Orinoco rivers. Many of the animal species of the reserve are adapted to lives in the rainforest and thus largely stay confined to the dense veins, using them to shelter and travel, while only rarely venturing into the open savanna. Some of the local species of special conservation concern, listed either because they are especially charismatic or increasingly endangered, will likely only ever be seen via camera traps. We suspect their presence, either from historical records or rare instances of footprints, but even the local ranch hands have never seen bush dogs, Speothos venaticus, a cryptic canid most closely related to the maned wolf, or even jaguars, Panthera onca, which are relatively common in other parts of South America like Brazil’s Pantanal wetlands.

Local landowners eager to document and conserve the wildlife of AKAE first reached out to me in Autumn of 2024 to see if I was interested in conducting novel research projects in their newly established reserve. They heard through the Stanford grapevine that I am investigating the consequences of land-use decisions on biodiversity and species interactions for my PhD dissertation and that I have a penchant for tropical fieldwork. Soon enough, utilizing satellite maps, I virtually assisted the local team in strategically placing a network of camera traps with the aim to document incidence of and habitat use by species of conservation concern. A longstanding dream of my AKAE collaborators was to capture the first footage of jaguars on the reserve’s lands. Camera traps are excellent for documenting larger mammals and birds, but they miss many smaller critters, especially cold-blooded reptiles and amphibians, the fauna I find most compelling to study, as they are immediately and severely affected by changes in temperature and humidity, symptoms of both land-use and climatic changes. Thus, the AKAE team and I planned an in-person field season for July 2025, the heart of the rainy season.

The first main objective of the field season was to travel throughout the reserve’s 65,000 acres of flooded savannas by motorcycle to re-strategize the placement of the camera traps. I wanted to find clear instances of large mammal activity, namely fresh tapir poops and newly trampled trails which began with tunnel-shaped entrances from the grasslands into the seemingly impenetrable forest veins. We would enter the forests where the mammals clearly did and we would place the traps in areas of obvious activity, like large fruiting palms with fresh evidence of consumption or in front of clay licks, crucial buffets of salt for various forest-dwellers. In an area where water levels fluctuate so severely, we also needed to make sure cameras were not placed in spots in which they would be inundated; one of the cameras we re-placed was more than a meter underwater when untied from its tree and retrieved. Day after day, we would ride the motorcycles through the flooded grasslands, slipping and falling frequently, while we gathered the cameras, strategized, found signs of large mammals, and repositioned our digital traps accordingly. At each camera trap site, we collected habitat data, detailing canopy closure and ground cover, so we can analyze trends between faunal presence and specific habitat characteristics. Before the end of the field season, a camera placed by a natural tapir bathing pool captured jaguars twice, the first ever documentation of South America’s largest land predator on the reserve. The winning logic was to follow the signs of the tapirs, just like the big cats seeking out their preferred prey.

The second main objective of the field season was to begin to document and detail the species we knew the cameras would not capture. I led visual encounter surveys for wildlife in the savannas and forests, mostly at night with headlamps. Nobody else on the team, including the ranch hands, had been traipsing through the jungle in the middle of the night. But nocturnal field work in the rainforests of Latin America is my specialty and miraculously quickly, the entire crew appeared comfortable, gleefully clearing out vines with machete strokes, wading chest-deep into flooded forests, and locking in to help me spot the glowing eyes of tree boas and caimans.

The field work was challenging. At this point, I have spent well over two years living in the rainforests of Latin America. And these were shockingly some of the most uncomfortable conditions I had experienced. Torrential rains flooded our quarters, made us topple our motorcycles into the mud an uncountable number of times (perhaps the reason I contracted schistosomiasis and giardiasis), and even deterred all regional pilots from coming to retrieve us from the middle of the Orinoco. To start the journey back to Bogotá, we had to travel nearly three hours by motorcycle before the sunrise, hurriedly register a brand-new airstrip with the government, and coordinate with a justifiably worried pilot to come get us from an area none of us had ever visited before. The entire field season was awesome. The team, none of whom had conducted any kind of scientific field work in their lives except for me, maintained incredibly positive attitudes, were superbly engaged, and demonstrably learned a ton about wildlife conservation, ecology, and bushwhacking through the rainforests by the end of the expedition.

The most valuable part of this field research was getting to work alongside a diverse and dynamic team of collaborators including the landowning family members, technological experts visiting from San Francisco and NYC, and local ranch hands, rubber boot wearing cowboys who live on the reserve and herd 1,200 heads of cattle on the backs of their Yamaha horses. We all engaged in a reciprocal teaching and learning exercise. My collaborators studied how to conduct conservation biology research while they explained to me the history of the land tenure, the local socioecological contexts, and why establishing and bolstering the AKAE reserve is crucial to the preservation of the Orinoco’s wild beasts. Our data now includes habitat characteristics like canopy closure and ground cover, thousands of camera trap photos, mostly mammals and birds, and hundreds of direct sightings of reptiles and amphibians. With our robust dataset we can analyze which species inhabit the AKAE reserve and which specific habitats they tend to use. Consequently, we can begin to assess the community of sensitive species in AKAE, and which habitat features are most crucial to their well-being. Our findings regarding habitat requirements of sensitive species should be broadly applicable to the Orinoco Basin and neighboring regions.

The Tinker Field Research Grant is allowing me to build out a new facet of my research program in Colombia, while supporting local collaborators’ conservation goals. I think it’s paramount that graduate student workers, especially estadounidenses like me, who are considering conducting field research in Latin America find community partners or local grassroots organizations which already have some semblance of defined goals and aims of what they want to achieve. And then you as the graduate researcher lend your expertise and capacity to helping realize and implement those goals.

Thank you to the Tinker Foundation and Stanford’s Center for Latin American Studies for funding and supporting my work.

Fieldwork Collage