Habitat
Olive Sparrows live year-round in dry, densely vegetated areas including thorn scrub, weedy fields, shrubby areas, and forests with dense understory vegetation. They avoid urban and suburban areas. In south Texas they are common in scrubby areas with mesquite, Texas ebony, and huisache.
Back to topFood
Olive Sparrows eat seeds, spiders, and insects. They forage on the ground, scratching at leaf litter to uncover seeds or insects, and occasionally pick insects from trees and shrubs.
Back to topNesting
Nest Placement
Olive Sparrows nest on or close to the ground (usually less than 5 feet above the ground). The nest is often located in a woody plant or succulent, or under a fallen log.
Nest Description
Olive Sparrows collect bits of dried grass and plant material to form a loose and bulky cup-shaped nest with a dome over the top.
Nesting Facts
Clutch Size: | 2-5 eggs |
Number of Broods: | 1-2 broods |
Egg Length: | 0.8-0.9 in (1.9-2.3 cm) |
Egg Width: | 0.6-0.7 in (1.5-1.7 cm) |
Egg Description: | White to pale pink. |
Condition at Hatching: | Naked with eyes closed. |
Behavior
Olive Sparrows often hop around in pairs in the cover of scrubby vegetation. While foraging they tend to hold their tails up and generally stay low to the ground, although they do move up into the shrub layer from time to time. Their flights tend to be short and low to the ground. Breeding pairs likely form monogamous bonds, though how long these pair bonds last is unknown. They seem tolerant of other birds and display little aggression even to Bronzed Cowbirds, which frequently lay eggs in the nests of Olive Sparrows.
Back to topConservation
Olive Sparrows are common and their populations increased between 1966 and 2015, according to the North American Breeding Bird Survey. Clearing of thorn scrub for cattle grazing in Texas likely caused population declines in the 1930s, and severe cold and drought may have caused declines in the 1980s, but since then Olive Sparrow populations appear stable. How they are faring south of the border is unknown. Partners in Flight estimates the global breeding population at 2 million. The species rates a 12 out of 20 on the Continental Concern Score, which means it is not on the Partners in Flight Watch List and is a species of low conservation concern.
Back to topCredits
Brush, Timothy. (2013). Olive Sparrow (Arremonops rufivirgatus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Lutmerding, J. A., and A. S. Love (2017). Longevity records of North American birds. Version 2017.1. Patuxent Wildlife Research Center, Bird Banding Laboratory, Laurel, MD, USA.
Partners in Flight (2017). Avian Conservation Assessment Database. 2017.
Rising, J. D. (1996). A Guide to the Identification and Natural History of the Sparrows of the United States and Canada. Academic Press, NY, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.