Thermal imaging drones are revealing hidden fire pockets beneath the scorched terrain of Cairngorms National Park months after a July wildfire consumed roughly 3,300 hectares of land.

Pete Short, a drone operator engaged since the blaze began, conducts predawn flights to scan for residual heat. "Every week I hope to find none," he says, "but on my last thermal sweep I detected eight anomalies."

During a recent patrol, Short’s equipment flagged a faint glow under a tree canopy. Ground verification confirmed a warm rock and rising smoke after soil disturbance, indicating an active subterranean fire. Such pockets, though invisible from the surface, can reignite larger outbreaks if left unchecked.

The original wildfire, documented by the Cairngorms National Park Authority, spread across 33 square kilometers at its peak. Five drone teams supported firefighting agencies during the emergency, navigating dense smoke, shifting personnel, and low-flying helicopters. Now, the focus has shifted to precision monitoring.

Ben Jones, senior site manager for the Royal Society for the Protection of Birds at Abernethy, emphasizes the logistical necessity of targeted response. "With limited personnel, we must prioritize locations where intervention will prevent escalation," he explains. Dr. Sarah Henshall of the park authority notes that ecological recovery timelines vary widely, from months to decades, depending on soil composition and species resilience.

Beyond immediate firefighting, drones are being repurposed for long-term ecological tracking. Pete Short is programming repeat flights along fixed routes to document vegetation regrowth and soil stabilization over time. "Consistent aerial surveys will reveal patterns of recovery that ground observations alone cannot," she states.

The technology also holds preventive potential. Short suggests that early canopy-level heat detection could alert authorities to emerging fires before they spread. "The critical window is when a fire is still small," he notes. "Rapid aerial assessment could make containment far more manageable."

During the recent patrol, another hotspot was identified and reported to land managers. While new green shoots and fungi now punctuate the charred landscape, officials caution that subterranean fires remain active beneath the surface. The combined use of thermal drones and ground teams continues to shape both suppression and recovery efforts in this recovering ecosystem.