Interesting Facts About the Pine Warbler

A group of pine warblers is called a "cone" of warblers.

The pine warbler, true to its name, lives high up on pine trees, and is seldom found anywhere else. It is probably the only wood warbler that consumes large quantities of seeds for food. It forms its nest high up on pine trees, hidden by the foliage. They show aggression towards birds entering their territory.

They fight by flying towards each other and locking beaks. In case of predators, the males and females pretend to have a broken wing and fly away from the nest to lure the threat away. After the eggs hatch, the parents and the hatchlings fly together as a unit.

It was initially classified in the genus Dendroica, which meant tree dwelling bird, but was later reclassified under Setophaga, a genus consisting of the family of warbler birds. The two genera were merged based on the genetic evidence provided by numerous geneticists. It is listed as a Least Concern (LC) species by the IUCN Red List.

Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Passeriformes
Family: Parulidae
Genus: Setophaga
Species: S. Pinus

Pine warblers are small, vividly colored songbirds. They are hefty birds with a long slender, notched tail. They have a tiny, sharp, olive colored beak, and a yellowish plumage. Yellow lines are present along the eyes of this bird. The males are a vibrant yellow color compared to the dull yellow color of the females. Both genders of this bird display two distinct white colored horizontal bars on their wings.

Their undersides and bellies are whitish in color, and the backs are olive. The females appear slightly Grey-brown in comparison to the males. The newborn chicks have no feathers, instead they are covered with dark brown down. They grow up to a maximum height of 5-6 inches and have a total wingspan of about 9 inches.

Pine warblers, as is evidenced by their name, inhabit branches of pine trees. They can be found in any forest that shows the presence of pine trees. When migrating, these birds migrate in mixed-species flocks, and during this period may dwell on shrubs or deciduous trees. They also visit bird feeders, occasionally. They have a widespread distribution along the eastern U.S.

They, primarily, are foragers, collecting food by poking their bills into nooks and crannies of the pine tree and pine cones. Sometimes, they are also seen foraging on the ground. They mostly consume seeds, berries, and insects. The insects they ingest, include ants, beetles, cockroaches, and grasshoppers. They survive mostly on seeds and other fruits during the winters.

During mating season, the plumage of the males becomes a more bright, vivid yellow, in order to attract females. The males even sing loudly to gain the attention of a female. When a female shows interest and accepts the male, the mating pair is formed.

The female then starts building their distinct cup-shaped nests, while the males keep intruders away, forage for food, keep the female entertained by singing songs. The nests are made of twigs and leaves, held in place by silk from caterpillar cocoons or spider webs.

The nest is lined on the inside with soft feathers and any other soft material that can be found. The pine warblers mate 1-3 times in a year. Each time, the female lays about 3-5 eggs. The female sits atop the eggs for 12-14 days, till they hatch. The males feed the females during this time.

The eggs are spherical and whitish, with specks of brown or olive on them. The newly hatched warblers are ready to fledge and fly about after 10 days. They take a year to mature into adults, and then can reproduce on their own.

The lifespan of pine warblers is not specifically known, but the longest known record is for 6 years in the wild.

They sing in short bursts, lasting just a few seconds.

When young hatchlings start to fledge, the whole brood along with their parents fly together as a unit.

They are the only warblers who visit bird-feeders, due to their affinity towards seeds.

They are often confused with yellow-throated vireos.

They are called "Paruline des pins" in French and "Chipe pinero" in Spanish.

The habit of feeding on seeds can lead to changes in their organs. Birds feeding voraciously on seeds have larger gizzards and longer digestion times as compared to those who ate fewer seeds.