Drones and Raptors: Balancing Monitoring Benefits with Disturbance Risks in Latin America

Researchers have long relied on drones to peek into raptor nests that are otherwise inaccessible from the ground. A new analysis, drawing on ten years of fieldwork in eight countries, reveals that the technology is a double-edged sword: it can provide vital data, yet it also provokes reactions in the majority of species studied. The study compiled 227 flights conducted between 2014 and 2024 over 119 active nests belonging to 27 neotropical raptor species. Overall, 81 % of the species exhibited some form of response when a drone entered their airspace. The intensity of those responses depended on ecological traits, breeding stage, and flight conditions. Defensive behaviors such as attacks and escape attempts were relatively rare but were linked to close approaches, prolonged hovering, or flights directly above the birds. Smaller, more agile raptors tended to launch attacks, whereas larger eagles usually opted to avoid confrontation. ## Field anecdotes illustrate the dilemma In Chile, an incident captured the tension between curiosity and risk. While a tiny drone was being guided toward a nest, a juvenile black-and-white hawk (Spizaetus tyrannus) swooped down and knocked the aircraft to the forest floor. The bird emerged unharmed, but the researchers faced the added challenge of retrieving the device from the canopy. The incident underscores a broader pattern: juvenile raptors often investigate novel objects out of playfulness, yet their actions can endanger equipment and potentially stress the animals. ## Practical guidelines emerging from the data Lead author Francisca Helena Aguiar-Silva emphasizes that each drone deployment should be anchored in a clear scientific or conservation purpose, not merely in the desire for photographs. She advises that flights be halted the moment a bird displays signs of stress or risk. This precaution is especially critical for sensitive individuals and threatened species, whose long reproductive cycles mean that a single disturbance could have outsized consequences. Researchers from the project note that drones have already shortened the time needed to confirm nest presence-from days or weeks of arduous climbing to a matter of minutes. Yet, even brief flights can trigger a spectrum of reactions, from heightened vigilance to vocal alarms and brief pursuits. The absence of an outright attack does not guarantee that the birds are unaffected. ## Balancing benefits with responsible use Ornithologists such as Fernando Angulo argue that, when used responsibly, drones may cause less overall disturbance than traditional methods like tree climbing or capturing birds for tagging. However, Angulo also points out the regulatory gap in countries like Peru, where no specific rules govern drone use for nest monitoring. He warns that without guidelines, the technology could become popularized by hobbyists, potentially increasing stress on vulnerable raptor populations. The compiled observations also debunk the notion of a universal safe distance. Variation in species size, flight behavior, and habitat means that what works for a harpy eagle in the Amazon may be inappropriate for a smaller hawk in the Andes. Consequently, the study calls for site-specific risk assessments and adaptive flight strategies tailored to each species’ ecology. In sum, the decade-spanning research paints a nuanced picture: drones are powerful tools for raptor conservation, but their deployment must be judicious, scientifically justified, and responsive to the birds’ behavior. By adhering to these principles, researchers can harness the technology’s advantages while minimizing the potential for harmful disturbance.