Initial tests point to the possible presence of the H5 virus in five swans and one heron, while another 20 swans and one goose have yet to be tested.
These birds were found dead mainly on the Drava near Maribor, but the heron was found near Slovenj Gradec, which might be the third crisis spot after Maribor and Muta.
The media quoted veterinarians as saying today that at present one could not speak of a bird flu epidemic among wild birds, which is why the pre-emptive culling of fowl is not envisaged in areas where bird flu has been registered among wild birds.
However, tomorrow a provision will go into force under which it will be mandatory to keep fowl in enclosed areas around the country. Monitoring will also be stepped up.
Special protection measures are already being implemented, such as disinfection and a ban on the transport of fowl, notably in the three crisis spots.