As autumn rolls around and the Lesser Spotted Eagle (Aquila pomarina) sets off on its yearly migration down to its winter quarters in Central and Southern Africa, we can look back on what has been a successful year for the Life Pomarina Conservation Project. Jointly implemented by Milvus Group, The Environmental Protection Agency Sibiu and the Romanian Ornithological Society, the project aims to ensure conditions to achieve and maintain favorable conservation status for the eagles across three Special Protection Areas (SPA) in Transylvania. Of these sites, Milvus Group is directly responsible for two: Dealurile Târnavelor – Valea Nirajului and Podișul Hârtibaciului.Increasingly endangered across the world, the Transylvanian Carpathians are one of the most important strongholds of the Lesser Spotted Eagle, with a population of between 2000 and 2300 pairs – over 22% of the total European Union population of the bird and 10% of the global population. Early each spring the eagles arrive to begin their breeding cycle, a fragile process with a naturally low success rate of between 0.25 and 0.6 fledglings per breeding pair. This is further encumbered by disturbances to their habitats, whether through forestry, intrusive agriculture or disproportionate competition from more resilient raptor species.
Over the course of the project, our work has been primarily focused on ensuring favourable nesting conditions for the breeding birds. As the Lesser Spotted Eagle is particular about its choice of breeding location, needing old forest stands for its nest and nearby open grasslands to hunt, our chosen sites are in the foot hills of the Carpathians, where the ancient forests meet the agricultural plains.
Our original task has been to locate as many raptor nests as possible. This is carried out in the winter months, when the nests are empty and the absence of leaves on the trees makes them easier to spot. Then, when the birds return in spring, we return to find which nests have been occupied by eagles, and which by other raptor species such as common buzzards (Buteo buteo), goshawks (Accipiter gentilis), honey buzzards (Pernis apivorus), or ravens (Corvus corax). As the birds are prone to swap nests from year to year, or simply start afresh by building a new nest in early spring, this task has to be carried out annually.
Since 2010, we have found over 700 raptor nests in the two SPAs, more than 50 of which were later identified as belonging to Lesser Spotted Eagles. This year, 290 raptor nests where located over the winter and, when spring came around, 16 of these were occupied by Eagles. Where the nests cannot be located directly, we use the alternative method of directly observing eagle pairs, often for five or six hours a day, as they hunt for prey or nesting material. By discerning the spot where they leave or enter the forest, we can track down their nest.
Unfortunately, the eagles are up against both human and natural antagonists, with illegal loggers often cutting down trees containing nests and strong weather conditions damaging the nests over winter. In this case, we have two resources. Most often we put up artificial nests, made from iron but filled with sticks to make it resemble the real thing. This year, we put out 18 such nests. Alternatively, where possible we repair and stabilize the nests, a simpler process which we carried out over 20 times this year, using the same material as found in a natural nest.
As a defense against disturbance from loggers both legal and illegal, we have created 17 buffer zones this year, designed to mark the especially sensitive areas in which the eagles nest. Unfortunately, the loggers largely turned a blind eye, suggesting in the future that stronger measures will have to be taken.
Finally, as preparation for next year, we fitted 19 eagle chicks with coloured rings so that they will be identifiable in the future, giving us further insight into the migratory and nesting patterns of these birds. Until then, let’s hope they have a safe journey and comfortable winter in Africa!