Pine Warblers live in pine or mixed pine-deciduous forest, and you’ll rarely see them out of a pine tree. They’re not particularly specific about which species of pines they’ll use, and the list includes jack, pitch, red, white, Virginia, loblolly, shortleaf, slash, sand, and pond pines. Their wintering habitat is similar to their breeding habitat. Migrating Pine Warblers sometimes use shrubs and deciduous trees.Back to top
Pine Warblers eat mostly caterpillars and other arthropods (including beetles, grasshoppers, bugs, ants, bees, flies, cockroach eggs, and spiders), but they also eat fruits and seeds (notably, pine seeds) especially during the colder months. They mostly forage by hopping along branches in the middles and tops of pines—moving more slowly than most warblers—while picking food from bark and needles. They sometimes feed from deciduous trees during migration. Pine Warblers may also feed on the ground and catch insects in the air.Back to top
Pine Warblers nearly always build their nests in pine trees, usually in pine or mixed pine-deciduous forest. Nests tend to be high in the tree and concealed among needles and cones.
The nest is a cup with an interior space about 1.5 inches across and equally deep. The female gathers most of the nest material, including grass, plant stems and fibers, bark strips, pine needles, twigs, and fine roots, binding them together with spider or caterpillar silk and lining the nest with feathers, hair, and plant down. In good weather she can finish the nest and begin laying eggs in 14 days. The male often escorts the female as she gathers materials, and occasionally helps build.
|Clutch Size:||3-5 eggs|
|Number of Broods:||1-2 broods|
|Egg Length:||0.6-0.8 in (1.6-2 cm)|
|Egg Width:||0.5-0.6 in (1.2-1.5 cm)|
|Incubation Period:||10-13 days|
|Nestling Period:||10 days|
|Egg Description:||White, grayish, or greenish white with brown speckles.|
|Condition at Hatching:||Undeveloped and downy.|
Pine Warblers typically forage and sing high in pine trees. Males are aggressive in the early breeding season, in fall, and in winter. They chase other birds and indicate aggression by gliding or flying with stiff wingbeats toward and then away from their opponent, in a circle. Birds sometimes fight by flying toward each other and locking bills in the air. In winter Pine Warblers forage in mixed-species flocks, keeping a few feet of space between each other. Males establish breeding territories in late winter or spring, singing persistently and chasing intruders. Both parents will perform broken-wing displays to lure predators away from the nest. After the young fledge the warblers move around in family groups.Back to top
Pine Warbler populations saw a steady increase of approximately 1.3% per year between 1966 and 2019, according to the North American Breeding Bird Survey. Partners in Flight estimates a global breeding population of 13 million and rates them 7 out of 20 on the Continental Concern Score, indicating a species of low conservation concern. Across much of their range, their native pine forests have been altered or destroyed by logging, development, and fire suppression. However, over the last few decades they have moved into areas where pines have been introduced into deciduous forests. In the 1950s, DDT that was sprayed to contain Dutch elm disease killed some Pine Warblers.Back to top
Lutmerding, J. A. and A. S. Love. (2020). Longevity records of North American birds. Version 2020. Patuxent Wildlife Research Center, Bird Banding Laboratory 2020.
Partners in Flight. (2020). Avian Conservation Assessment Database, version 2020.
Rodewald, Paul G., James H. Withgott and Kimberly G. Smith. (2013). Pine Warbler (Setophaga pinus), version 2.0. In The Birds of North America (P. G. Rodewald, editor). Cornell Lab of Ornithology, Ithaca, New York, USA.
Sauer, J. R., D. K. Niven, J. E. Hines, D. J. Ziolkowski Jr., K. L. Pardieck, J. E. Fallon, and W. A. Link (2019). The North American Breeding Bird Survey, Results and Analysis 1966–2019. Version 2.07.2019. USGS Patuxent Wildlife Research Center, Laurel, MD, USA.
Sibley, D. A. (2014). The Sibley Guide to Birds, second edition. Alfred A. Knopf, New York, NY, USA.
Stephenson, T. and S. Whittle (2013). The Warbler Guide. Princeton University Press, New Jersey, USA.