Hummingbirds Double Their Body Fat Before Leaving Pennsylvania

Quick Take

• Before leaving Pennsylvania, hummingbirds undergo a dramatic physical transformation that most backyard birders never notice, and this transformation explains the sudden feeder frenzy every fall. See the pre-migration transformation →
• Juvenile hummingbirds make a 1,000-mile-plus solo migration with zero guidance, and the reason they can do it reveals something surprising about how migration actually works. Explore the solo migration route →
• There's a persistent myth about backyard feeders that causes some homeowners to take them down too early, and this belief may be doing more harm than good.
• Males and females don't leave Pennsylvania on the same schedule, and the timing gap between them is wider than most people expect. See the male vs. female timeline →

Hummingbirds start to fill Pennsylvania’s skies around late April or early May. In fact, most Pennsylvania residents associate the arrival of hummingbirds with the first bloom of blue flowers known as vinca. These birds migrate to the United States to raise their offspring in a more temperate climate. But when do hummingbirds leave Pennsylvania? Continue reading to find out everything you need to know about hummingbird migration patterns.

When Do Hummingbirds Leave Pennsylvania?

The most common hummingbird species in Pennsylvania, and the only breeding species, is the ruby-throated hummingbird, known for its iridescent, reddish throat patch. Hummingbirds usually arrive in late April to May. Males may arrive up to two weeks earlier. Ruby-throated hummingbirds are typically found in eastern deciduous and mixed deciduous coniferous forests throughout the state. Their habitats include forest edges, open woods, orchards, wet meadows, gardens, thickets, parks, and areas along streams.

After the breeding season, males begin migrating south in early August. Females and juveniles may remain until early September, with some individuals waiting until October or later. Hummingbirds are solitary and fiercely territorial, so they do not migrate as a group. Even juveniles who have never migrated make the journey on their own. Hummingbirds’ sporadic migration pattern ensures that resources are not depleted simultaneously.

Where Do Hummingbirds Go When They Leave Pennsylvania?

As hummingbirds migrate individually, there are several areas they travel to during winter. Some will spend the colder months along the Gulf Coast, while others winter along the outer banks of the Carolinas. However, most of them fly to Mexico and Central America, typically as far south as Panama. After the migration, sightings of hummingbirds in Pennsylvania are rare, but there are some stragglers — old or injured individuals who are not strong enough to migrate.

How Long Does It Take Hummingbirds to Migrate South?

Migrating is no easy task. In fact, hummingbirds start to prepare for their taxing migration by doubling their body fat, eating more nectar from flowering plants and feeders. They also catch more insects for protein so they have the energy to make the long journey south. So don’t be surprised if you see more hummingbirds at your feeder during fall — they are stocking up. Keeping your backyard feeders filled will not discourage them from flying south, but it provides a critical source of nectar on their long journey.

It takes a hummingbird approximately 63 hours to fly around 1,897 miles to the Mexican border at a speed of 30 mph. However, they also migrate to Panama, which is a distance of about 4,528 miles over land, or 2,149 miles across the Gulf of Mexico, taking around 150 hours over land or 71 hours across the Gulf, respectively. While some hummingbirds can fly 500 miles non-stop across the Gulf in around 20 hours, others take a more relaxed approach when migrating over land.

Types Of Hummingbirds in Pennsylvania

The ruby-throated hummingbird is the only hummingbird species that is commonly seen in Pennsylvania. However, a few western species, such as the rufous hummingbird and the calliope hummingbird, have been recorded as rare or accidental visitors, typically during the fall and winter.

Ruby-Throated Hummingbird

The male ruby-throated hummingbird has a bright red patch on its throat, also known as a gorget, and boasts several distinctive markings. For example, they have bronze and green feathers along their backs, with light bellies and short legs. Females’ gorgets are white with a gray tint.. Ruby-throated hummingbirds weigh approximately a tenth of an ounce, about the weight of a penny. Once fully mature, they can measure about 3 inches long. Ruby-throated hummingbirds are omnivores, consuming both insects and nectar. Around 60% of their diet consists of insects like aphids, caterpillars, spiders, and tiny eggs from trees and leaves. In Pennsylvania, these hummingbirds frequently feed on wildflowers like bergamot, honeysuckle, salvia, and petunias.

Rufous Hummingbird

The male rufous hummingbird has a beautiful red-to-orange patch on its throat and charcoal shades along its back and belly. Females have green backs and rust-colored throats. These tiny birds are about 3 inches long and weigh one to two-tenths of an ounce. Rufous hummingbirds prefer habitats near deciduous forests or gardens, yards, and parks in urban areas. Females nest near the top of pine, birch, or spruce trees, ensuring they have overhead branches protecting them. These birds feed on insects and nectar but prefer flowers like lilies, heaths, penstemon, and larkspurs. They also get protein from catching gnats mid-flight.

Calliope Hummingbird

The Calliope hummingbird is primarily green with tints of yellow and blue. Males have a deep magenta throat, while females are more conservative with green backs and white bellies with shades of peach. These tiny hummingbirds are the smallest birds in North America, measuring about 3 inches long, with a hunched posture that makes them appear even smaller. Calliope hummingbirds like to inhabit cooler mountain regions during mating season. They prefer thickets near streams, mountain meadows, or previously logged forests. Calliope hummingbirds consume nectar from tubular or cup-shaped flowers, which larger hummingbirds tend to avoid, so they face less competition. They also feed on sap wells and catch insects.