The reproductive Steller sea lion rookery at Kamen Kozlova in the Kronotsky Nature Reserve is the last remaining breeding ground off the coast of Kamchatka. Out of three historical breeding sites for the region’s largest eared seals, only this location has survived to the present day. Approximately one hundred pups are born here annually, and the survival of the entire Kamchatka population directly depends on the stability of this habitat. The Steller sea lion is endemic to the North Pacific – acting as a key indicator of the overall health of the local marine ecosystem.
The population of these marine mammals is steadily declining, resulting in the species being listed in the Red Data Book of Russia and by the International Union for Conservation of Nature. Environmental specialists identify anthropogenic factors as the primary cause of this demographic downturn. Intensive commercial fishing severely depletes the food supply available to the pinnipeds, while the extensive use of commercial fishing nets regularly leads to animal mortality – predominantly through entanglement.
The breeding season takes place throughout June and July. During these months, any extraneous noise can trigger panic and cause a mass stampede of adult seals into the water, which inevitably leads to the crushing and death of newborns. To completely eliminate physical human presence, remote monitoring methods have been utilized for over fifteen years. Automatic camera traps safely record the distinct stages of colony formation: the post-migration arrival of males, the establishment of harems, and the birth of pups.
Research efforts have been significantly expanded this season through a new drone-based monitoring initiative. Unmanned aerial vehicles are operated at a strictly maintained safe altitude of fifty meters to avoid disturbing the wildlife. Because newborn pups have a coat color that blends seamlessly with the rocky terrain of the rookery, detecting them on standard visible-spectrum orthomosaics is highly challenging. The implementation of parallel thermal imaging effectively resolves this complication – enabling biologists to record the exact number of offspring without posing any risk to the colony.