Urine representing the three feeding classifications of mammals, namely carnivore, herbivore and omnivore, was used as a sodium-containing bait in butterfly traps and at feeding stations, to determine any preferences by nectivorous temperate butterflies. Twenty individuals representing three families were trapped, with no significant difference between the different urines. Carnivore urine was significantly more attractive to puddling butterflies than herbivore or omnivore urine. This study was unable to determine if puddling butterflies were capable of seeking out sand with a specific sodium content or if amino acids and/or volatiles influenced their choice.