Birds – Migrating birds – Discover-Nature

Spring Migration

Meteorological spring starts Sunday, and we are already starting to hear the calls of early migratory birds, heading north from southern wintering grounds, working to establish territory their among the best nesting sites available.

Red-winged blackbird, Agelaius phoeniceus, singing by Rhododendrites, May 2023

Some birds, including red-winged blackbirds, Agelaius phoeniceus, get their cue to start spring migration as temperatures get warmer. These species head to prairies, forests, and wetlands to claim a location they can protect, call for a mate, and establish a nesting site with good protection and food sources. Other birds, including many warbler species, return in spring when daylight hours lengthen. Generally flying at night, they use star positions and the Earth’s magnet field to guide them. If nights are stormy or heavily overcast, early morning may find hundreds of them waiting in fields for clear skies. Birds may also stop for a day or two in areas located on the southern shores of any large body of water to rest and feed before crossing.

Red-winged blackbird, *Agelaius phoeniceus,* flock at sunset by Jerry Segraves

Bird species around the world generally follow established flyways, established routes over specific locations between their southern and northern territories. Many migration routes do not follow a straight path. Some species have historical stopover or feeding locations that provide a rest point along the way. Other species may not be able to cross a mountain range; or a large body of water can act as a barrier for land birds, but may be a required food source for wetland birds.

Arctic tern, *Sterna paradisaea*, adult & juvenile by Charles J Sharp, Aug 2025

Arctic tern, *Sterna paradisaea*, in flight by Charles J Sharp, Aug 2025

Long distance migration routes are most common for birds wintering in subtropical and tropical areas and breeding in the northern hemisphere. Long migrations in the southern hemisphere are far less common because there is less land near the South Pole to support breeding activities. The record holder for migration distance is the Arctic tern, Sterna paradisaea, overwintering in Antarctica and breeding in Arctic locations, a round trip between 30,000 and 55,000 miles. Some shorter migrations are between upper and lower altitudes in mountainous regions.

Penguin migration map by Fred Cooke
& Jenni Bruce, Aug 2011

Dusky grouse male, *Dendragapus obscurus*, displaying by US NPS

Most birds migrate in flocks, which reduces the energy needed to fly long distances and provides added protection against predators. Penguins migrate without flying. Most penguin species swim between locations, covering up to 1,000 miles round trip. A few species cover long distances on foot, including dusky grouse, Dendragapus obscurus, in the Rocky Mountains which walk from lower to higher elevations. However, a flock may encounter unfavorable weather or flying conditions that causes a large number of birds to stall in one location, introducing other risks including depleted food sources and predation by land-based animals.

At the Jurica-Suchy Nature Museum, we host a nature walk every other week to observe changes in our campus including the birds that are moving through the area. There are many birding groups worldwide that provide opportunities to observe and learn about migratory birds in every location. Consider joining a group, or take your own bird walk as we have clear days and warming temperatures and see who’s on the move in your area.

Hummingbirds

It is getting to the end of summer, and many bird species that winter in Central and South America will soon be starting their migrations. Of the 320 species of hummingbirds, 15 spend the summer breeding in North America, from the Gulf Coast states to southern Canada, before returning to winter habitat farther south. Only one species, the Ruby-Throated Hummingbird, Archilochus colubris, breeds east of the Mississippi River.

7 of the 15 hummers that breed in North America:
- Anna’s Hummingbird, Calypte anna, by Alan Scmierer-USFWS, Mar 2007
- Black-chinned Hummingbird, Archilobus alexandri, by Paul Crook-USFWS, Jun 2024
- Blue-throated Hummingbird, Lampornis clemenciae, by Alan Schmierer-USFWS, Jun 2024
- Broad-billed Hummingbird, Cynanthus latirostris, by Alan Scmierer-USFWS, Mar 2022
- Buff-bellied Hummingbird, Amazilia yucatanensis, by Alan Scmierer-USFWS, Jan 2010
- Broad-Tailed Hummingbird, Selasphorus platycercus, by Tom Koerner-USFWS, Feb 2024
- Allen’s Hummingbird, Selasphorus sasin, by Wendy Miller-USFWS, Jun 2024

Hummingbirds have a very high metabolism with a normal heart rate of 250 beats per minute that accelerates to almost 1250 beats per minute when in flight. They consume large amounts of nectar each day to get enough sugar to support their energy requirements. Several small grooves running the length of their tongue funnel nectar into their throat by capillary action, a force that causes liquid to rise in a small tube without needing to use air to suck the liquid in. They also eat any small invertebrate to fulfill protein, vitamin, and mineral needs. Hummingbirds snatch insects mid-air while in flight, poach them from spider webs, and glean tiny moth caterpillars from new leaves and branch tips. Another foraging method uses the blast of air beneath their powerful wings to roll over leaves on the forest floor, revealing the insect life below.

^{Anna’s hummingbird catching insects by Stan Lupo, Jul 2023}

Hummingbirds do not bond with a mate. Females establish a territory that optimizes the available nectar and offers multiple nest sites. Males establish a territory based on encountering as many females as possible. Both will defend their areas from other hummingbirds, as well as other nectar feeders including butterflies and bees. Daily feeding starts on the outer edge of their territory to chase out any overnight interlopers and ends with nectar sources deep inside the area’s interior. Males will breed with as many females as possible. Females may have more than one brood of eggs each year, either concurrently or one brood following another.

Nests are about 2″ in diameter, built of small twigs, lined with soft plant material, and covered on the outside with greenish-gray lichens. Nests are bound to branches with spider silk, usually in a forest clearing. The lichens provide camouflage by making the nest appear as a large knot when seen from below. Females reach breeding age at the end of their first year, and can breed throughout their lifetimes. They construct one or more nests, each containing two white eggs, the size of peas, which are incubated by only the female for 14 to 16 days. The male takes no part in raising the young birds, coming together with the female only during mating.

^{Allen’s Hummingbird nest, by Mike’s Birds, Mar 2013}

^{Ruby-throated hummingbird on nest with lichen, by Lorie Shaull, Jul 2020}

Hummingbirds found in the western portions of North America travel overland migration routes. However, midwestern and eastern birds fly non-stop over the Gulf Of Mexico. A hummingbird can increase its fat reserves and double its body weight in the 7 to 10 days prior to the overseas trip. Through studies using banded birds, we have learned that they fly alone, normally at night, along with large flocks of other birds. Young birds, making the trip for the first time, can successfully navigate the migration route with no prior training. Their guidance system, how it works, and how it is learned are all still a mystery.

No hummingbird species are listed as endangered. However, hybridization among species is common, and their small size and great speed make them very difficult to count and track. Little data is available about population size changes and movements; however, more birds have been found over-wintering as far north as the Gulf Coast states of North America.

At the Jurica-Suchy Nature Museum, we have numerous bird specimens on display, including hummingbirds. We welcome you to come in and learn more about these amazing creatures.

Remaining 8 species that breed in North America:
Calliope Hummingbird, Selasphorus calliope, by Barbara Wheeler-USFWS, Nov 2021
Costa’s Hummingbird, Calypte costae, by Wendy Miller-USFWS, May 2020
Rivoli’s Hummingbird, Eugenes fulgens by Doug Greenberg-USFWS, Aug 2017
Lucifer Hummingbird, Calothorax lucifer, by Jim Gain-USFWS, Mar 2022
Ruby-throated Hummingbird, Archilobus colubris, by Alan Scmierer-USFWS, Jun 2024
Rufous Hummingbird, Selasphorus rufus, USFWS, Jun 2024
Violet-crowned Hummingbird, Amazilia violiceps, by budgora, Mar 2014
White-eared Hummingbird, Basilinna leucotis, by Alan Scmierer-USFWS, Mar 2022

Bird Migration

Migration began in early September and is just passing the peak period with several millions of birds in flight every night. Migration is defined as a seasonal and predictable event that is repeated annually. Other types of movements for bird populations include dispersal, occurring when a bird leaves the place where it was raised to find a mate, and irruption, occurring when a group of birds leave a site because winter is so harsh they are forced to move to find food.

Insect eater Eastern Kingbird, Tyrannus carolinensis, by Dennis Murphy, Jun 2016

Neotropical ruby-throated hummingbird, Archilochus colubris, by Rick-from-Alabama, Jun 2013

Migration requires that many species move hundreds of miles or more across and between continents. There are high risks involved, so why do birds leave a territory they have established a home in to go elsewhere for a portion of the year? Insect eating birds must move south in winter as food sources die off in significant numbers in northern regions when temperatures drop. Neotropical species require constant warmer temperatures. Many birds that spend the winter in equatorial belts move north in spring to take advantage of abundant summer food supplies and fewer nest predators including parasites. These birds must migrate south in autumn to remain in seasonally warm weather.

Golden eagle, Aquila chrysaetos, soaring on Seedskadee NWR by USFWS Mountain-Prairie, Jan 2014

Blue jay, Cyanocitta cristata, in flight by Jo Zimny, Jan 2019

Many species fly at specific times during a twenty-four hour period. Thermals, upward moving columns of air, are created by the sun. Soaring birds including sandhill crane, golden eagle, and turkey vulture flying during daytime hours, depend on thermals to get airborne and remain aloft. Some daytime species are dependent on food sources that are only out in warmer, daytime air. For birds that do not ride the air currents, including blue jay and white-crowned sparrow across the northern United States, using powered flight generates much body heat, which is easily compensated for by cooler nighttime temperatures. Nighttime air is also less turbulent, making the flight smoother and requiring less energy.

Junco, Junco hyemalis, by Colin Durfee, Mar 2020

Migration distance varies widely among species and even within one species. In winter in northern Illinois, we often see dark-eyed juncos, Junco hyemalis, on our backyard feeders. This species breeds in summer in northern Canadian regions. Studies show that young males migrate only a short distance to southern Canada, while adult females migrate the greatest distance to the southern U.S. Adult males and young females migrate several hundred miles to winter in north-central regions. Observations of young males show they are first to stake out new territories in the spring for breeding. Adult males are aggressive enough to establish a territory upon their return. Adult females can arrive later to find a mate with an already established territory. And young females are simply learning the routine until they grow older.

Canada geese, Branta canadensis, in V formation by Floris van Halm, Jan 2010

Winds at flying altitudes are the main factor in determining whether a day’s travel will be long or short and use lots of energy or only a little. Strong headwinds reduce flight speed by up to half and require more energy. Strong tailwinds speed the flyer along with less effort. Birds that fly in flocks have more advantages. As air flows around a bird in flight, it is deflected upwards from the wingtips. Birds flying in a “V” formation, such as Canada geese, use the air coming off their neighbors wings to make their flight easier and use up to 40% less energy. As you watch a formation, notice the lead bird gets no energy savings but changes position every few minutes with another bird, so each takes a turn at the leader’s position.

Research in recent years has contributed to many sites having online tools for monitoring and learning about all aspects of migration. For fun facts and up-to-date information, take a look at:

Migration Dashboard (birdcast.info) shows migration information including dates, birds, counts, and routes by U.S. state or county.
Bird Migration Explorer (explorer.audubon.org) from Audubon shows maps of current migration activity.

Wood Warblers

Flashes of color accompanied by beautiful melodies

With a gray head, olive back, a yellow belly and a black chest, this species likes dense forests with berry laden shrubs.

Mourning Warbler, Geothlypis philadelphia, by Tom Benson, May 2013

It is still early spring in northern Illinois, and wood-warblers, in the family Parulidae, are starting to migrate through our area. Noted for their bright breeding plumage, these small songbirds display a variety of colors from bright yellows to deep blues and greens with occasional flashes of orange and red. For Spring Bird Count, always the first Saturday in May, an average of 30 species will be observed in Illinois.

**With brown-olive backs, yellow bellies and throat, and a rusty cap during spring breeding, these birds like weedy fields or areas of scattered trees & shrubs**
Palm Warbler, Setophaga palmarum, by Tom Wilberding, May 2019

**Olive-green with white belly, yellow faces & black throats, frequenting any woody habitat**
Black-throated Green Warbler, Setophaga virens, by Fyn Kynd, May 2016

Warblers migrate mostly at night, and will wait for favorable, southerly winds to fly. During the day, they rest in tall trees, favoring oaks and willows, while feeding until the next available night for migrating. Most species are insect eaters and require food several times during the day to supply the energy needed for migration. Some may supplement their meals with seeds and nectar when available.

**Gray backed with reddish-brown head, breast, and flanks, a black face & cream belly, this bird favors mature, coniferous forests**
Bay-breasted Warbler, Setophaga castanea, by Doug Greenberg, May 2019

**Bold black & white stripes with two large black spots under the tail, this species likes mixed forests & trees of all ages**
Black-and-white Warbler, Mniotilta varia, by Dennis Church, Oct 2019

Warblers sing a wide variety of songs that are unique for each species, assisting in identification. Songs are used for establishing territory and attracting mates. Songs are mainly sung by males, although female songs have been documented. One set of songs is sung mainly during the day for attracting mates, and they are relatively simple tunes. A second set of songs, with a much more complex structure, is used for defending territory. These are usually only heard early in the morning.

**Gray head with bright white eyering, a green back, yellow chest, white belly & yellow under the tail, this species likes thick tangles of new growth in forest clearings**
Nashville Warbler, Leiothylpis ruficapilla, by Mike’s Birds, Sep 2015

**A gray head, black eye mask, yellow throat & yellow belly with black striping, these birds like young spruces in conifer forests**
Magnolia Warbler, Setophaga magnolia, by Stan Lupo, May 2016

Several well-known observation spots are located in our area. Some that you may find interesting include Illinois Beach State Park, Zion; Montrose Harbor and the Magic Hedge, Chicago; Midewin National Tallgrass Prairie, Wilmington; and Elsen’s Hill in West DuPage Woods Forest Preserve, Winfield. You can attract them to your own backyard by planting native trees and shrubs, especially oaks. Be sure to have a shallow dish or birdbath with plenty of water available.

**Bright orange face & throat bordered on sides & top by black or gray, this species likes tall trees in coniferous forests**
Blackburnian Warbler, Setophaga fusca, by Steven Kersting, May 2019

**Gray head & throat, white eyering, olive back & yellow belly, found in open woods**
Connecticut Warbler, Oporornis agilis, by Tom Murray, Sep 2021

Additional information is available from several online resources. For identification of common species seen in northern Illinois, view Chicago Field Museum Field Guide 999 . To find out what species are currently being observed and their locations, check out the Illinois Audubon Migration Dashboard . Look for quick flashes of color among trees and shrubs, and listen for beautiful trills and melodies as you are out walking this spring.

**Yellow with reddish streaks & large, black eyes, this bird forages for insects in open woodlands**
Yellow Warbler, Setophaga petechia, by Gerard Cachon, Jul 2021

**Gray back & head with flashes of white in wings, bright yellow faces, sides, & rumps, they like open coniferous forests & edges**
Yellow-rumped Warbler, Setophaga coronata, by Mick Thompson, Mar 2021

Spring Migration

March is the month where we experience the greatest number of bird species migrating northward to spring and summer breeding locations. Birds that spend the winter at the southern end of their range in northern Illinois will be migrating back to Canadian and tundra regions. Other species will migrate to our area from southern locations to find a mate and breed here in spring and early summer.

Common Redpoll, *Acanthis flammea* by Scott Heron, February 2019

American Tree Sparrow, *Spizella arborea* by Fyn Kynd, February 2017

Snowy Owl,
by TNS Sofres, September 2011

Far northern regions have a shorter breeding season, but research has revealed several possible advantages to these locations. These include an abundance of food in the summer due to a lack of competition for it, fewer parasites that survive the winter and exert less impact on returning bird populations, and fewer predators that live in these regions. Some birds that spend the winter in northern Illinois but you may not see again until next fall are the American tree sparrow, snowy owl, short-eared owl, long-eared owl, and common redpoll.

Sandhill Cranes, *Antigone canadensis* by Jim & Robin Kunze, October 2020

Sandhill Cranes, *Antigone canadensis*
by Tim Lumley, December 2018

Many more birds migrate from southern locations into our area to breed over the spring and summer months. Let’s take a look at a few with catchy behaviors. Sandhill Cranes, Antigone canadensis, fly in a “V” formation at altitudes of 500 to 2500 feet and can cover up to 500 miles in ten hours. Their nests are a simple platform of vegetation found in marshy areas. You can oftentimes hear their loud, warbling call as they soar overhead, and may get to observe their dancing courtship displays, often performed in the early morning hours.

American Woodcock, *Scolopax minor* by Fyn Kynd, April 2015

American Woodcock dance, by USFS, April 2018

The American woodcock, Scolopax minor, a member of the Sandpiper family, likes moist woodlands and brushy marsh. During spring migration, males often call at dawn and dusk with a buzzy ‘peet’. At dusk, calls are accompanied by a display involving a spiral flight up from the ground to almost 300 feet where the bird plunges downward, making several arcs back and forth, to a hard landing only feet from where it took off. Combined with another display called the Woodcock dance, it’s all about showing off, and displays gets repeated until dark and again each night until he attracts a mate.

Blue-winged Teal, *Anas discors* by shell game, January 2012

Redhead Duck, *Aythya americana* byTeddy Llovet, March 2010

Several waterfowl species move into the lakes, rivers, and ponds just as soon as the ice melts. Dabbling ducks have bills adapted to remove food including aquatic vegetation, seeds, and invertebrates from the top few inches of water. Common species in our area include northern pintail, mallard, and blue-winged teal. Diving ducks are found on deeper lakes and rivers that may thaw a bit earlier. Their food lives in deeper water and includes fish, mollusks, and bottom vegetation. Birds include canvasback duck, redhead duck, hooded merganser, and common merganser.

Golden-crowned Kinglet, *Regulus satrapa* by Kenneth Cole Schneider, October 2017

Killdeer, *Charadrius vociferus* by Curt Hart, June 2006

Purple Martin, *Progne subis* by Nathan Hamm, May 2006-a

There are numerous other species to watch for including swallows, purple martin, eastern phoebe, yellow-bellied sapsucker, golden-crowned kinglet, killdeer, common grackle, and hermit thrush. Bluebirds, robins, and red-winged blackbirds are migrating to northern Illinois and points farther north, spreading out throughout much of the Midwest.

Eastern Bluebird, *Sialia sialis* by Danielle Brigida, January 2019

American Robin, *Turdus migratorius* by
C Watts, June 2013

Be on the lookout for these new arrivals in your neighborhood. Walking trails in nearby marsh and woodland areas may allow observation of one of the more spectacular courtship displays, many of which occur in Chicago collar-county forest preserves. March is a busy start for the breeding season, and you can find more species and information on their impending arrivals at Cornell University’s eBird website at ebird.org/home.