Olivaceous Woodcreeper Sittasomus griseicapillus

  • Order: Passeriformes
  • Family: Furnariidae
  • Polytypic: 15 subspecies
  • Authors: Michael A. Patten




This species hitches up a trunk or large branch in a manner typical of woodcreeper species and recalling a treecreeper (Certhia sp.). The tail is used as a prop while the bird travels, often rapidly, in either a straight line or spirally around the trunk or branch. Relative to typical members of the Furnariidae, rectrices of woodcreepers are adapted to support a bird’s weight (Tubaro et al. 2002). Flight is rapid and direct.


No information.

Agonistic Behavior

In a study in the Atlantic Forest of Brazil, Brooke (1983) reported that niche overlap in foraging height and preferred habitat was moderately high with the slightly larger Lesser Woodcreeper (Xiphorhynchus fuscus) but was low with the considerably larger White-throated Woodcreeper (Xiphocolaptes albicollis). Brooke did not, however, report on aggressive interactions between the species. By contrast, in a study in Amazonia, Pierpont (1986) reported that even though diet and substrate overlapped only moderately with the considerably larger Striped Woodcreeper (Xiphorhynchus obsoletus), the smaller species did attack the larger on one occasion, although the large species seemed tolerant.


Little information. Home range varies between 3.5 ha (Costa Rica; Powell 1979) and 9 ha (southeastern Peru; Pierpont 1986). It may be that territories are defended only during the breeding season given that this species tended ant swarms in forest and shade coffee plantations in comparable numbers January–April, but their numbers decreased markedly in coffee May–June (Roberts et al. 2000). At the least, this pattern suggests that birds have a larger home range outside the breeding season.

Sexual Behavior

No information.

Social and interspecific behavior

The Olivaceous Woodcreeper often is encountered as it forages singly (Slud 1964, Skutch 1967, Brooke 1983, Thiollay and Jullien 1998) or, at times, in pairs (Ridgely and Tudor 1994, Willis and Oniki 2001), yet the species routinely joins mixed-species flocks in either understory or the canopy (Davis 1946, Willis 1960, Stotz 1993, Cohn-Haft et al. 1997, Puebla-Olivares 2001, Ghizoni 2009). This species spent ~60% of its time in mixed-species flocks at a site in southeastern Peru, at which birds moved among flocks in the same stratum or between flocks in understorey and canopy (Munn and Terborgh 1978). Joining a mixed-species flock may depend on habitat—in southwestern Tamaulipas, Mexico, this species occurred in 50% of flocks in humid pine-oak forest and cloud forest, but <5% of flocks in tropical semi-deciduous forest or dry pine-oak forest (Gram 1998). Similarly, flocking propensity varied between 13% and 55% among eleven study sites in the Atlantic Forest of southern Brazil (Brandt et al. 2009). The propensity to join flocks also may depend on season—in the Atlantic Forest of Brazil, individuals tended not to flock during the breeding season (Davis 1946), and flocking was reported to be common in winter in Guatemala (Land 1970)—or when conditions are windy or rainy (Powell 1979). On average, birds join flocks for ~41 min. (Powell 1979).

This species may join mixed-species flocks tending army ant swarms (see Food). Moreover, it sometimes sallies after insects dislodged by troops of tamarins (Leontopithecus spp.). Passos (1997) documented associations with foraging troops of the Black Lion Tamarin (L. chrysopygus). Depending on season, birds associated with these tamarins 3–9% of the monkey’s activity period, with one association lasting 35 min. Hankerson et al. (2006) reported that the Olivaceous Woodcreeper was among five species of woodcreeper that followed foraging troops of the Golden-headed Lion Tamarin (L. chrysomelas), and this woodcreeper follows the rare Golden Lion Tamarin (L. rosalia) in southeastern Brazil (Kuniy et al. 2003).


No information.

Recommended Citation

Patten, M. A. (2011). Olivaceous Woodcreeper (Sittasomus griseicapillus), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.oliwoo1.01