New bat-friendly lights
So far, 17 of the 30 species of bats living in Slovenia have been recorded in Goričko. Their most important roosts are the bell towers and attics of churches or chapels, the basements and attics of abandoned buildings, and the cavities in trees in the woods. Bats leave their daily roosts immediately after sunset, when there is the largest abundance of insects in the air to feed on. Research has shown that bats living in the buildings lit by artificial light fly out later because they get confused about the time of day. Because the bats leave their roost later in the night, they miss the peak of insect activity and that has an adverse effect for the nutrition of females and pups. If the building is being completely illuminated, bats can even leave the building permanently.
Church in Grad before and after (photo: G. Domanjko)
In December, as part of the Gorička Krajina project, we replaced 25 old lights with 13 new bat-friendly lights, illuminating eight churches in Grad, Bodonci, Gornji Petrovci, Križevci, Markovci, Dolenci, Domanjševci and Kobilje, and a chapel in Fokovci. These are all buildings with evidented bat roosts of the greater mouse-eared bat or lesser horseshoe bat. New lights with special masks of the silhouettes of the churches will reduce the light pollution of the Natura 2000 site Goričko, as they only illuminate the façade and the roof. The lights do not illuminate the exit openings, used by bats to fly out. The lights have weaker lightbulbs of maximum strenght of 150 W and emit warm, yellow-white light. Power consumption will be also reduced by up to 10 times. Measures are in accordance with the Regulation on limit values for light pollution in the environment.
By agreement with the building managers, the new lights will not illuminate the church and chapel all night, but will be turned off after 11 p.m. From now on, the negative effects of excessive light pollution will have positive effects not only on nocturnal animals but also on humans.
Municipality of Šalovci followed our good practice in reducing light pollution within the Natura 2000 site Goričko and already replaced the light next to the bell tower in Budinci.
