We are equipped with a thermal camera and a zoom camera, which enable precise and at the same time unobtrusive monitoring of birds. By using a drone we can observe birds at a safe distance, which significantly reduces disturbances during the sensitive nesting period. We also fly high enough not to disturb the presence of birds.
And it was precisely during these counts that we witnessed an exceptional sight – we observed three bitterns (Botaurus stellaris)! From the data collected we conclude that there are two females (one sits on the nest, the other is still building the nest) and a male who is looking for food.
Bittern (Botaurus stellaris) is a large, rare and secretive marsh bird from the heron family. Although it is related to the more common grey heron, it differs from it quite a bit – both in appearance and in lifestyle. It is an exceptional master of camouflage, as it spends most of its time hidden among dense reeds. When it senses danger, it freezes in an upright posture and with its head turned upward, thereby blending completely with the surroundings. That is precisely why it is extremely hard to spot.
Its deep, booming call, which resembles blowing into a bottle and can be heard miles away, is often the only sign of its presence. This distinctive sound is also the source of its name.
In Slovenia, the bittern is a very rare and endangered nesting bird. It nests only in a few special, larger and tranquil wetlands with abundant reeds. The Lake Cerknica and its surroundings, located in the heart of Notranjska Park, represents the only known nesting area of the bittern in Slovenia. This confirms the exceptional conservation value of our very special piece of the world. The bittern builds its nest on a floating platform in the middle of the reed bed. It feeds on fish, amphibians, insects and other small wetland animals, most often at dusk or at night.
The biggest threat to the bittern at Lake Cerknica is probably an overly rapid drop in water level during the nesting period. When the water level falls, prey availability near the nest decreases, which means that the females must leave the nest for longer periods – their chicks are more exposed to ground predators during this time.
The bittern is a protected species in Slovenia and is included in the Natura 2000 network. Its presence is an indicator of healthy, preserved wetlands and a symbol of the natural value of Notranjska Park.
The implementation of extensive nature conservation projects exceeds the financial capacity of the local community, therefore Notranjska Park regularly applies for projects with the possibility of co-financing by the European Union.
The implementation of large-scale conservation projects exceeds the financial capabilities of the local community, therefore Notranjska Park regularly applies for projects with the possibility of co-financing from the European Union.
