Drones are widely viewed as a boon to the world’s expanding conservation efforts. With their thermal imaging sensors, drones can track endangered species as well as predators and poachers.  They can also detect stress patterns in flora and alert  conservationists to the need for remediation.  But drones can also pose a threat to some animal species.  Especially noteworthy are birds, which drones, like most human aircraft, resemble – and indeed, mimic.  While reports of drones striking and actually killing a bird are rare, drones have the potential to disturb and distort bird life in less obvious but still pernicious ways.

Noise from drones can disrupt bird feeding and mating patterns, and when drones fly too close to nests or rookeries, they can scatter the birds and even provoke them to attack.  One incident of great concern to bird enthusiasts occurred in May 2021 when a drone crashed on the Bolsa Chica Ecological Reserve, 30 miles south of Los Angeles.  Bolsa Chica Ecological Reserve is home to 3,000 Elegant Terns, so named for their grace and beauty, but also for their sensitivity to their environment.  The drone crashed just as the Elegant Terns had begun incubating their eggs.  Startled and perhaps terrified, the entire Tern flock suddenly fled the Reserve and left their progeny to perish.

The incident has caused enormous controversy among California conservationists and bird enthusiasts everywhere.  Under FAA regulations, the Bolsa Reserve is supposed to be off-limits to drones but in recent years, as public visits to the Reserve have increased (in part due to COVID tourist restrictions elsewhere), Terns have faced increased noise interruptions, not just from drones (which are still uncommon intruders, analysts say), but from bicyclists and unruly groups of children and youth.

Drones, however, have a unique ability to disturb and threaten the Terns by flying directly into the flock as if they were a potential predator.  And unlike other birds that will steadfastly defend their breeding ground, it only takes the flight of one or two terrified Elegant Terms to cause the entire flock to flee in unison, as they did in this latest incident, with tragic results.

In the wake of Bolsa Reserve, the FAA is increasing its efforts to educate UAV enthusiasts and the public at large about the joys and risks associated with drone use. The FAA’s online map denoting areas off limits to recreational drone flying failed to mark the Reserve as one of those areas, perhaps contributing to the recent tragedy. Bird enthusiasts, who aren’t big fans of drones to begin with, are still angry about the incident and want to see tougher restrictions on drone flights and stiffer penalties for violations. As more UAVs fill the skies, the potential for more drone-bird mishaps is bound to increase.