The six species caught up in these encounters read like a roll call of Andean biodiversity. Alongside the condor, tapir, and brocket deer, the researchers documented dogs chasing the Andean fox (Lycalopex culpaeus), the white-tailed deer (Odocoileus virginianus), and the Andean tapeti (Sylvilagus andinus), a rabbit that the International Union for Conservation of Nature lists as Data Deficient. The cases span four provinces, Napo, Pichincha, Tungurahua, and Loja, and reach elevations from 1800 to nearly 4000 meters above sea level, covering páramo grasslands, montane forests, and the buffer zones of national parks. Eight of the eleven incidents occurred within protected areas themselves, including the Antisana, Atacazo, and Alto Pita water conservation areas, the Ponce-Palugillo wildlife refuge, the Chakana reserve, Cayambe-Coca National Park, and the private reserve Madrigal del Podocarpus. The remaining three took place in human-transformed habitats less than 4.07 kilometers from protected boundaries.

Some of the most consequential records involve the Andean condor, Ecuador’s national bird and one of its rarest. In December 2021, at 3994 meters in the Antisana water conservation area, an adult condor was observed feeding on a deer carcass that was approximately 95 percent consumed. When three dogs ran toward the carcass, the condor took flight immediately. The dogs sniffed the dead animal, did not feed on it, and left thirty seconds later, but the interruption is precisely the kind of interference that matters for a scavenger that depends on unpredictable carrion resources. Antisana hosts the most important population stronghold of the species in Ecuador, where fewer than 150 condors survive. This is only the second documented case of direct negative interaction between dogs and condors in the country; in July 2019, a condor nestling in Pichincha lost its tail in a dog attack and now lives in captivity.

The indirect toll on condors may be even graver. Between November 2014 and June 2016, researchers working in the buffer zone of Antisana National Park found dogs present at 28 carcasses, accounting for 40 percent of the total activity time recorded there, and their presence was negatively associated with both the residence time of condors and the number of independent condor events. More disturbing still, at least 16 percent of condors killed in Ecuador between 2007 and 2021 had consumed carrion deliberately poisoned by farmers retaliating against dogs that had attacked their cattle. During that same period, poisoning and shooting together eliminated up to 31 percent of the local estimated condor population. The chain of harm thus runs from uncontrolled dog populations, through livestock conflict, to poisoned carcasses that indiscriminately kill scavengers, a cascade that conservation managers cannot address without tackling the human-dog interface itself.

The mountain tapir records are among the most medically detailed in the study. On 24 March 2023, firefighters in Quijos, Napo Province, alerted environmental authorities to a female mountain tapir calf, roughly five months old, found on a farm after being attacked by dogs in the forest. Rescuers transported her to the Quito Zoo, where veterinarians diagnosed myiasis, septicemia, a secondary fracture, inflammation and infection from multiple dog bites, and osteomyelitis caused by bone trauma. Three weeks later and 15.5 kilometers away, a second female calf, about eight months old, was rescued in Papallacta after a dog attack in Cayambe-Coca National Park. She had four bite lesions, infection, osteomyelitis in an exposed bone lesion, luxation, and coxofemoral arthrosis. Laboratory analysis of both animals revealed antibiotic-resistant bacteria, including Staphylococcus aureus and Escherichia coli. Both tapirs eventually died of these chronic degenerative conditions, and while the authors caution that they cannot definitively attribute the deaths to the attacks, the veterinary findings illustrate how a single dog encounter can set off a fatal cascade of trauma and infection.

These cases carry implications beyond tapir conservation. The global mountain tapir population is estimated at no more than 2500 individuals, and the species is classified as endangered with alarming declines reported across its range in Colombia, Ecuador, and Peru. A confirmed case of a mountain tapir dying of rabies after a bite from an infected dog in Pichincha, documented by earlier researchers, combined with the new records of antibiotic-resistant bacteria, suggests that tapirs’ exposure to human-related disturbances threatens not only an endangered species but also public health and food security. Dogs act as reservoirs and vectors of diseases that can spread across large areas and multiple species, potentially disrupting the functioning of entire ecosystems, a dynamic well established in the broader literature on domestic carnivores as invasive species.

Camera traps captured the subtler forms of harassment with striking clarity. In the Atacazo conservation area in February 2022, a camera trap photographed an Andean tapeti sprinting through the detection field, followed fourteen seconds later by three dogs running in the same direction. In October 2023, at the Alto Pita conservation area, a camera installed at a horse carcass recorded an Andean fox feeding warily at 10:56; at 11:02 the fox bolted, and one second later two dogs ran past the camera in the same direction before returning to feed on the carcass themselves, a sequence that documents both harassment and interference with scavenging. In Loja’s Madrigal del Podocarpus reserve in November 2023, a little red brocket deer ran across a trail, doubled back, and slipped into the forest; fourteen minutes later, two dogs followed the identical path and entered the forest exactly where the deer had vanished, displaying what the authors describe as clear active search and pursuit behavior.

Direct observations filled out the picture. In 2014, three dogs were seen chasing a white-tailed deer across a canyon in the Chakana reserve; in 2018, four dogs chased and harassed a white-tailed deer at Itulchachi, just 70 meters from the nearest settlement; and in February 2024, two dogs were observed frantically sniffing the ground and searching for an Andean tapeti among the bushes below a lookout point, less than a minute after the rabbit had passed. In January 2025, in Tungurahua Province, two dogs were recorded chasing, harassing, and biting a little red brocket deer. The researchers calculated that the recorded cases lay between 0.07 and 10.51 kilometers from the nearest human settlement, and they note that they cannot determine whether the dogs involved were feral or free-ranging owned animals, a distinction that matters for designing interventions but not for the underlying problem.

The behavioral consequences of these encounters may be as damaging as the physical ones. Previous research in Ecuadorian páramos has shown that both the little red brocket deer and the mountain tapir shift their activity patterns to avoid dogs, partitioning time to reduce the chance of encounters. The Andean fox tends to become more nocturnal in areas with dogs, and its occupancy was better predicted by the presence of dogs than by habitat loss or fragmentation. Such fear-induced behavioral changes can reduce foraging efficiency, alter predator-prey dynamics, and effectively shrink usable habitat for species already squeezed by agriculture and development. The new study also suggests dogs competed with, or at least interfered with, the feeding of the Andean condor and the Andean fox, extending earlier findings of carrion competition at Antisana.

The authors call on the Ecuadorian government, universities, animal welfare groups, nongovernmental organizations, and civil society to invest in assessing and reducing dog impacts on native vertebrates in high Andean ecosystems. Because the human-dog interface is a complex social-ecological system, they argue that mitigation strategies must go far beyond simple dog removal, addressing inadequate or absent legislation, irresponsible pet ownership, the unregulated intentional and unintentional feeding of dogs, poorly functioning animal shelters, power asymmetries among stakeholders, and uncontrolled dog populations. With a dog-to-human ratio of roughly one to 4.7 across South America, the scale of the challenge is enormous. But the alternative, an Andes without condors, tapirs, and brocket deer, is one that conservationists say the region cannot afford.

Subject of Research: Negative impacts of domestic dogs on native Andean vertebrates in Ecuador

Article Title: New records of domestic dog negative impacts on native vertebrates in the Ecuadorian Andes

Article References: Restrepo-Cardona, J. S., Monar-Barragán, P., Orihuela-Torres, A., Araujo, E. E., Narváez, F., Pineida, R., Trujillo, B., Recalde, A., Salazar, A., Fernández, D., Castel-Tapia, M., & Kohn, S. (2025). New records of domestic dog negative impacts on native vertebrates in the Ecuadorian Andes. Neotropical Biology and Conservation, 20(2), 93-101. https://doi.org/10.3897/neotropical.20.e148221

Image Credits: AI Generated

DOI: 10.3897/neotropical.20.e148221

Keywords: domestic dogs, Andean condor, mountain tapir, wildlife conservation, Ecuador, Andes, disease transmission, protected areas, human-wildlife conflict, invasive species, camera traps, biodiversity