Measurements
Both Sexes
- Length
- 5.1–5.5 in
13–14 cm - Wingspan
- 7.5–9.1 in
19–23 cm - Weight
- 0.3–0.5 oz
9–15 g
Relative Size
- Smaller than a White-throated Sparrow; larger than a Northern Parula.
Other Names
- Paruline des pins (French)
- Chipe pinero (Spanish)
Cool Facts
- The Pine Warbler is the only warbler that eats large quantities of seeds, primarily those of pines. This seed-eating ability means Pine Warblers sometimes visit bird feeders, unlike almost all other warblers.
- Most warblers leave the continental U.S. for winter, but the Pine Warbler stays in the Southeast and is one of the first to return northward in spring. It arrives as early as February in areas just north of the wintering range and may begin breeding by late April.
- The Pine Warbler’s closest relative seems to be the Olive-capped Warbler, which lives in pine forests of the West Indies. One of its next closest relatives is the ubiquitous Yellow-rumped Warbler, even though the two don’t superficially look much alike.
- Migrant Pine Warblers from the northern part of the range join resident Pine Warblers in the southern United States in winter. Sometimes they form large flocks of 50 to 100 or more.
- Individual Pine Warblers can show physical differences according to their diets: birds that were experimentally fed with mostly seeds developed larger gizzards (the organ that crushes food into pieces) and longer digestion times, while birds that ate fruit had longer intestines and shorter digestion times.
- The oldest recorded Pine Warbler was a 6-year old bird captured in Massachusetts in 1932.
Habitat
Forest
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.
Food
Insects
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.
Nesting
Nesting Facts
- 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.
Nest Description
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.
Nest Placement
Tree
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.
Behavior
Bark Forager
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.
Conservation
Least Concern
Pine Warblers have been increasing since the mid-twentieth century, moving into areas where pines have been introduced into deciduous forest. However, across much of their range, their native pine forests have been altered or destroyed—by logging, development, and fire suppression. As a result, some Pine Warbler populations have declined, such as those in parts of New York, Connecticut, and Massachusetts. In the 1950s, DDT that was sprayed to contain Dutch elm disease killed some Pine Warblers.
Migration
Partial migrant. Pine Warblers from the northern U.S. and Canada migrate to wintering grounds in the southeastern U.S. Individuals that breed in the Southeast typically stay there year-round.
Backyard Tips
The only warbler that regularly eats seeds, the Pine Warbler will eat millet, cracked corn, sunflower seed, peanuts, and suet from elevated feeders in winter. It may also eat fruits from bushes and vines, like bayberry, flowering dogwood, grape, sumac, persimmon, and Virginia creeper.
Find This Bird
The best way to find Pine Warblers is to narrow them down by habitat and voice. Head for a pine forest in the eastern United States (check a range map for specifics), and then listen for a clear, steady, trilling song. Chipping Sparrows and Dark-eyed Juncos sound very similar and can occur in the same habitats, so be aware you might find these birds instead. Pine Warblers tend to stay high in pines and can be obscured by tufts of needles, but a bit of patience is likely to be rewarded.