The attraction said it recently placed 15th in an unofficial ranking of Europe's top 126 zoos, a few points behind those in Basel, Rotterdam, and Cologne but ahead of those in Copenhagen, Dublin, Amsterdam, Hannover, Nuremberg, Hamburg, and London.

The zoo earlier upgraded its heating system, with European Union support, to tap the thermal water of the nearby Széchenyi Baths.

Last year, its consumption of gas and electricity dropped by double digits.