Polish tradition dictates that carp (and other fish dishes) be served on Christmas Eve. Unfortunately, many people also have the custom of buying live carp, which are often kept in the bathtub until they are killed for Christmas Eve dinner.
The goal of Polish environmental organization Klub Gaja's campaign is to minimize the suffering of these sentient animals. The campaign basically asks people not to buy live carp, - noting that the way these animals are transported, kept, and later killed all cause a lot of needless suffering to these animals.
(All of the resources are in Polish only)