Common Diuca-Finch Diuca diuca

  • Order: Passeriformes
  • Family: Thraupidae
  • Polytypic: 4 subspecies
  • Authors: Megan Cookson, Casey H. Richart, and Kevin J. Burns

Diet and Foraging


Common Diuca-Finch is part of the year-round ground foraging guild (de Casenave et al. 2008, Cueto et al. 2013). Its diet consists primarily of surface seeds (Marone et al. 1997), although more arthopods are consumed during the warmer seasons (Jaramillo 2011). Grass seeds made up approximately 80% of the stomach contents of samples from Argentina (Jaksic and Lazo 1999). It also commonly eats the seed arils from Capparis atamisquea and the seeds of Prosopis flexuosa (Blendinger 2005). It is are not of any agricultural concern because it feeds on spilled seeds and does not disperse seeds (Jaramillo 2011). The diuca-finch changes its seed preference in response to short-term fluctuations in seed abundance as well as in response to presence of other seed eating birds (Lopez-Calleja 1995, Jaksic and Lazo 1999). Common Diuca-Finch prefers larger seeds such as E. cicutarium, but eats smaller seeds such as those of Opuntia sp., in addition to a wider variety of grass seeds in the winter (Lopez-Calleja 1995, Blendinger and Ojeda 2001, Jaramillo 2011, Cueto et al. 2013).

Foraging Behavior

The Common Diuca-Finch is part of the year-round ground foraging guild (de Casenave et al. 2008, Cueto et al. 2013). It forages by walking on the ground, with a diet consisting of primarily surface seeds (Marone et al. 1997). In the warmer seasons, more arthropods are found in the diet, and foraging occurs more arboreally on lower shrubs (Blendinger 2005, Jaramillo 2011). Also in the summer, more nocturnal seed foraging occurs (Kelt et al. 2004). It obtains its food from the ground in over 90% of foraging observations (Blendinger 2005). The results of 451 (120 individuals) foraging observations in the nonbreeding season, and 247 (70) observations in the breeding season are recorded in Table 2 (de Casenave et al. 2008).

Table 2. Foraging manuevers and microhabitat
Season nonbreeding breeding
Glean from ground 92.1% 76.0%
Glean from foliage 0.8 1.4
Glean on herbaceous plants 3.5 3.8
Glean on fruits 1.7 7.1
Glean on other plant material 0.8 11.4
Leap 1.1 0.1
Sally-strike - 0.1
Mesquite (Prosopis flexuosa) 1.7 4.3
ChaƱar (Geoffroea decorticans) - 7.1
Other shrubs - 7.1
Low shrubs 1.7 1.4
Grasses 4.6 0.7
Forbs - 3.1
Arboreal stratum 1.7 12.9
Shrub stratum 0.8 6.6
Herbaceous stratum 1.7 0.7
Ground 95.8 79.9

Recommended Citation

Cookson, M., C. H. Richart, and K. J. Burns (2018). Common Diuca-Finch (Diuca diuca), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA.