Naturalists have advised locals not to feed the swans in Krakow.
Technically, you probably shouldn’t be feeding them at all. Bread is, of course, not part of swans’ natural diet, and feeding it to them in large quantities could cause problems with digestion and nutrition. Furthermore, anyone who has gotten near a swan knows that they can get quite aggressive toward people and pets.
This time of year, though, it is especially important not to feed the swans, as doing so might persuade them not to fly south for the winter. This in turn could find them unequipped to a harsh Polish winter. They could freeze, get stuck in the ice (in which case the Krakow fire will be dispatched to rescue a 12-kg feisty fowl), or have to be fed manually by the city since they will be unable to access their regular food sources.
This advice comes via Radio Krakow from Nowy Sącz environment director Grzegorz Tabas, but it also applies to the swans living in Krakow’s Vistula River.