The Short-tailed Finch appears to be omnivorous but its precise dietary requirements remain largely unknown. The stomach contents from five specimens collected near Pongo, and the Rio Choquekkota Valley, Bolivia, contained a wide variety of seed sizes, with some as large as 8 x 5 mm (Remsen et al. 1982). The species mainly forages on the ground, probing or digging into the soil to a depth of 2.7 cm, and has been observed digging up and feeding on the 'bulb-like' or 'clove-like seeds' of Gentianella aurantiaca in south-east Peru (Lloyd et al. 2005). The species often uses the same technique when foraging on moss clusters or lichen on boulders or Polylepis trees (Lloyd et al. 2005). The use of these foraging substrates suggests that arthropods make up some (only a small?) proportion of its diet.