Eastern screech-owl: Tiny hunter of the night

In the middle of the night, an 8-inch bundle of feathers and hollow bones projects a haunting, mysterious sound. It sounds like the rising and falling whinny of a horse, followed by a piercing tremolo. Though it sounds far away, the bird—an eastern screech-owl—could likely be right above your head (that is, if you are out in the middle of the woods at night).

Young eastern screech-owl. Photo by Carol Freeman.
Young eastern screech-owl Photo © Carol Freeman

A year-round, common resident of northern Illinois, the eastern screech-owl, (Megascops asio) is primarily found in woodlands; it prefers trees with natural cavities near a field with a stream or shallow river. But it can also be found in wooded residential neighborhoods, possibly even in your backyard. It could be lurking in a small tree cavity during the day, snoozing while waiting for its evening foray to your back porch light to catch a moth.

The eastern screech-owl comes in two color morphs—red (rufous) and gray. Ornithologists aren’t sure why, but they do know parent morphs of the same or different colors can producer young of either color. Those who get a look at this owl under moonlight or in its daytime roosting hole will see a dark streaking on the owl’s breast that blends well with the tree’s bark. It has a 20-inch wingspan, piercing yellow eyes, and tiny ear tufts. (Actually, these are not ears, but rather feather tufts it can move to communicate or use for camouflage.) As with most owls, the ears of the eastern screech-owl are situated asymmetrically on either side of its head—one is higher than the other. This arrangement enables it to zero in on its prey through triangulation, by turning its head to the left and right and moving it up and down a few times.

The Chicago Botanic Garden regularly holds programs offering visitors a chance to learn about the habits of Illinois owls as well as hear and see the diminutive eastern screech-owl. Join us for our next Owl Prowl sessions.

These owls will nest in a natural cavity or man-made nest box, adding no material of their own. The female lays four to five white, round eggs and incubates them for about 26 days. The male brings her food when she’s on the eggs and also after they hatch. She breaks up the prey into morsels to feed her young. In another 26 to 30 days, the young fledge, but they remain dependent on the parents for food for a few months longer before heading out on their own to hunt.

PHOTO: An eastern screech-owl snuggles in to its nest in winter. Photo by Carol Freeman.
An eastern screech-owl snuggles into its nest in winter. Photo © Carol Freeman

What do they hunt? An eclectic diet: eastern screech-owls eat moles, mice, shrews, and flying squirrels year-round, but also prey on cicadas, crickets, moths, and worms during warmer months. Like other owls, the screech-owl regurgitates pellets that contain undigestible fur and bones. Finding pellets beneath a tree is one clue to its presence. 

You can purchase screech-owl boxes and hang them in a tree in your wooded backyard with hopes of attracting them to nest. At night, listen for the mysterious whinny of the screech-owl near a woodland. You never know how close one may be. Or on a sunny day, especially in winter, look at natural cavities and trees—you might see a screech-owl snoozing at the entrance.

The eastern screech-owl is the October bird species highlighted by the Forest Preserves of Cook County. Come #birdthepreserves with the FPDCC; view the list of upcoming events for free events near you.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

Red-Bellied Woodpecker: Colorful Year-Round Woodland Denizen

When someone first hears the name of the red-bellied woodpecker, it doesn’t make sense. The bird has a bright red crown and nape, but where’s the red belly? Actually, there is a small pinkish tinge on the bird’s stomach, but it’s difficult to see unless you look for it with binoculars (and if it’s not covered with gray feathers).

PHOTO: A red-bellied woodpecker looking for food. Photo by Carol Freeman.
A red-bellied woodpecker looking for food. Its eclectic diet consists of nuts, berries, seeds, insects, and suet from feeders. Photo © Carol Freeman

Unfortunately, the name “red-headed woodpecker” was already taken by another bird—incidentally, much rarer in northern Illinois—so ornithologists named this common, year-round bird the red-bellied woodpecker.

The red-bellied woodpecker (Melanerpes carolinus) has creamy-to-white underparts, and a black-and-white, zebra-patterned back. The male’s forehead is red; the female’s is creamy white. (By contrast, the red-headed woodpecker’s entire head is blood red, and its back is solid black with white patches on the wings.) The red-bellied woodpecker’s preferred year-round habitat is woodlands, and the oak, pine hardwood, and maple forests of the eastern United States. Occasionally, it can be found in wooded suburban neighborhoods.

Woodpeckers have long, barbed tongues. A woodpecker’s tongue is so long that when it is not extending it to grab a meal deep within a crevice, it pulls it in, and wraps it around the inside back wall of its skull, almost to its nostril holes. Because they can get food from deep within a tree instead of relying on what is readily available, they are well-suited to spend winter in northern Illinois, when other insect-eating birds need to move south.  

PHOTO: Female red-bellied woodpecker.
Female red-bellied woodpecker by www.birdphotos.com [CC BY 3.0], via Wikimedia Commons

If a red-bellied woodpecker visits your yard, you may be able to observe some interesting behavior: the woodpecker puts a nut into the crevice of tree bark, then hits the nut with its beak to get to the yummy morsel inside. It also may store the food there to eat later.

The woodpecker makes its presence known in woodlands and yards or at feeders by calling “querr” or “cherr-cherr” several times, or giving various chattering sounds. Its boisterous noises and colorful plumage add cheer to a cold winter’s day.

In February or March, the male red-bellied woodpecker begins seeking places to excavate cylindrical cavities—in dead trees or dead limbs of trees—and enticing a female to mate and lay eggs, which happens in late March and early April.

As with many birds, red-bellied woodpeckers will nest in the same location year after year. The male typically builds a new cavity—often in the same tree, near the old one—each season. The nest cavity is from 10 to 14 inches deep and usually built on a limb (as opposed to the trunk). The female lays four to five white eggs each season, and both parents incubate the eggs for about 12 days and take care of the nestlings, which fledge in another 24 to 27 days.

Numbers of this beautiful, common bird have grown across most of its range over the past 50 years, according to the North American Breeding Bird Survey. Once most common and found mostly in central and southern Illinois, it has expanded its range northward in the state in the past century, including into northern Illinois, where it had been decidedly rare in the early twentieth century.

The red-bellied woodpecker is the November bird species highlighted by the Forest Preserves of Cook County. Come #birdthepreserves with the Forest Preserves; view the list of upcoming events for free events near you.


©2016 Chicago Botanic Garden and my.chicagobotanic.org. Additional photos by Ken Thomas and Tom Friedel.

Black-Capped Chickadees Are Preparing for Winter

Chick-a-dee-dee-dee.

Most people recognize that familiar call of the black-capped chickadee. It’s often heard in late summer and fall as chickadees gather in family groups and small feeding flocks to prepare for the winter.

The chickadee’s song—translated as “Hey, sweetie,” (though you can’t often hear the third syllable)—is reserved for late winter, spring, and summer, when the bird is courting and nesting. Nothing brightens a mid-February day more than when a chickadee sings because to those who hear it, the song signals spring’s arrival.

PHOTO: Black-capped chickadee (Poecile atricapillus). Photo © Carol Freeman.
Because of its curiosity and propensity to visit feeders, the black-capped chickadee (Poecile atricapillus) can often introduce youngsters and adults to bird-watching. Its telltale black cap and throat with white cheeks makes it easy to identify. Photo © Carol Freeman

The black-capped chickadee is the September bird species highlighted by the Forest Preserves of Cook County. Come #birdthepreserves with the FPDCC; there is a free walk at the Garden on September 17, 7:30 to 9 a.m.

The black-capped chickadee is considered a non-migratory species—it can survive the harsh winters of northern Illinois. These birds can lower their body temperature when sleeping at night, which protects them from freezing.

While some birds need to leave the region in fall because insects and other food will soon become difficult to find, chickadees know how to find insect larvae overwintering in tree bark (although flocks of chickadees do make small geographic movements, depending on food availability in colder months).

They also stash seeds to eat later, and unlike squirrels, they remember where they put them. Chickadees eat berries and animal fat in winter, and they readily come to feeders feasting on seeds and suet. Supplemental food, especially sunflower seed from feeders has been shown to help these little balls of feather and hollow bones survive when it gets really cold and wet outside. Those who feed birds can observe an interesting behavior in chickadees—they form a hierarchy, meaning the top chickadee gets to eat at the feeder first—it snatches a seed and leaves, then the second in command gets its turn.

PHOTO: A chickadee enjoys a plentiful and tasty treat in early February: berries.
A black-capped chickadee enjoys a plentiful and tasty treat in early February: berries.

In February, chickadees begin singing and looking for a cavity hole in which to nest—and there’s a wide variety of homes they’ll find suitable. They’ll choose abandoned woodpecker cavities and man-made nest boxes, or excavate their own small, natural cavities. Chickadees will nest in rotted, old wooden fence posts and abandoned mailboxes, and a pair once built a nest in an old shoe hanging from a line.

The female builds a cup-shaped nest with moss for the foundation, lining it with rabbit fur or other soft material. She has one brood each year, laying an average of seven to eight eggs. After 12 days of incubation, the young hatch, then remain in the nest for another 16 days. When they fledge, they continue to follow their parents, calling and begging for food. Come winter, they travel in small feeding groups, often with nuthatches, titmice, and other small songbirds.

West Nile, which came to the U.S. about 17 years ago, likely may not have affected black-capped chickadees as much as some thought, according to a recent study.

Though people were seeing fewer chickadees in their backyards and in woodlands when the virus came to the region, a 2015 study showed that overall black-capped chickadee numbers have not been affected by the mosquito-borne disease, especially compared with other species. Studies will continue on how the virus is affecting bird populations—but one thing is for certain—when the virus struck, it reminded humans not to take for granted the common birds they enjoy. And the black-capped chickadee is certainly a species that humans enjoy watching and hearing.

©2016 Chicago Botanic Garden and my.chicagobotanic.org

Ruby-throated hummingbird migration begins

In August, when the jewelweed and cardinal flowers bloom, the ruby-throated hummingbird is migrating. It’s perfect timing, because the hummingbirds get energy for their journey southward by sipping nectar from the blossoms of these plants native to northern Illinois.

Ruby-throated Hummingbird photo © Carol Freeman
Ruby-throated hummingbird © Carol Freeman

The ruby-throated hummingbird is the August bird species highlighted by the Forest Preserves of Cook County. Come #birdthepreserves with the FPDCC; there are two free upcoming walks at the Garden.

PHOTO: A female ruby-throated hummingbird (males have the ruby coloring) enjoys a sip of salvia nectar in Circle Garden in summer.
A female ruby-throated hummingbird (males have the ruby coloring) enjoys a sip of salvia nectar in the Circle Garden in summer.

The ruby-throat is the only hummingbird to breed in eastern North America, and these tiny jewels are somewhat common nesters in Cook County woodlands. They become more numerous in late summer and fall, as those that nested farther north pass through on their way to their winter homes in Mexico and Central America.

The ruby-throated hummingbird (Archilochus colubris) wears emerald green on its back and crown, and in good light, the male reveals an iridescent red throat. (During fall migration, you’ll see males as well as females and young, both of which lack the ruby throat.)

They return to Illinois in April and May, seeking nectar from early blooming trees and shrubs as well as insects and spiders.

It’s at this time you might get lucky enough to observe the courting male as he flies in a U-shape and also buzzes in front of a perched female. Buzzes? Yes! Hummingbirds aren’t silent—you can hear their wings buzz and vocalizations from their throats when they’re defending feeding territory or seeking a mate.

The female builds a thimble-sized cup nest on a horizontal branch, adding grasses and spider webs, lining it with plant down and then covering the outside with lichens and dead leaves. The young hatch in about 15 days, and remain in the nest for another 20 days or so as the female brings them insects.

An aerial wonder, the ruby-throated hummingbird, can beat its wings 53 times per second, and can fly backward and upside down.

You can attract ruby-throated hummingbirds to your yard by planting the flowers they love—tubular and brightly colored in red hues—and by putting up feeders. Hummingbirds are fun to watch at feeders as they have spats in flight trying to hoard the food to themselves. 

To make hummingbird food, add ¼ cup white sugar to 1 cup boiled distilled water. Stir to dissolve, then cool before you put it into the feeder. It’s not necessary to put red food coloring in the water. Use a red feeder to attract the hummers. Hang out of direct sunlight, and clean and refill often.

Most ruby-throated hummingbirds are gone by the end of October in this area. You can put your feeders back up in April when they return.


©2016 Chicago Botanic Garden and my.chicagobotanic.org

Osprey: Fish-eater returns as breeder in Cook County

Several decades ago, an osprey would be a rare—if not impossible—sight in Cook County in the summer. But now, thanks to the ban on certain pesticides (including DDT), and the creation of osprey nesting platforms, the fish-eating bird is breeding again in local forest preserves.

The osprey looks somewhat like an adult bald eagle, but doesn’t have the eagle’s full white head or tail. Instead, it has a broad brown band through the eye, a brown back, and white belly. An osprey flies with a crook in its wings. Immature bald eagles, with their mottled black and white plumage, can easily be mistaken for ospreys. In summer, visitors can watch an osprey (Pandion haliaetus)—with its 6-foot wingspan—soar above a lake, then plunge in to snatch a meal with its talons to bring to its young. 

PHOTO: Osprey in flight.
Osprey in flight
Photo © Carol Freeman

Once endangered in Illinois, the osprey disappeared as a breeding bird from Illinois about 60 years ago. Scientists think, as with the bald eagle, that when the osprey ingested certain pesticides, the chemicals caused its eggs to thin and crumble during brooding. After DDT was banned, state biologists hoped the osprey would return to breed in Illinois. But the bird needed some help, including cleaning up local waterways and providing nesting areas.

In the 1990s, Cook County Forest Preserves officials, following the lead of biologists in other states, began erecting osprey nesting platforms—40-inch-wide platforms atop 50-foot-tall posts—in the preserves, hoping the ospreys would use them to nest.

It worked. The tall structures gave the ospreys a 360-degree view of their surroundings, something scientists say the birds need when choosing a nesting spot. Today, at least a dozen osprey pairs breed in Cook County, with several more in other nearby counties.

This year, the Chicago Botanic Garden installed an osprey nesting platform, and is waiting to see if a pair will find it to their liking.

According to officials of the Cook County Forest Preserves, 12 osprey pairs bred on man-made platforms in the county in 2014, including at Long John Slough at the Little Red Schoolhouse in Willow Springs. A pair of osprey tending to their nest atop a platform was photographed at Saganashkee Slough in the Palos Preserves this year by Wes Serafin, a long-time proponent of helping ospreys return as a breeding species to Cook County.

PHOTO: An osprey keeps a tight grip on lunch.
An osprey keeps a tight grip on lunch.
Photo © Carol Freeman

The ospreys return in April, often to the same platform they used the previous year. They build a nest of sticks atop the platform, adding new ones each year. The female lays three to four eggs, which hatch in about 38 days. While she broods, the male fiercely defends their territory and brings food to his mate. The young remain in the nest for about two months, begging constantly for food. Then they take their first flights off the platform.

Watching an osprey grab a meal can be fascinating. The bird appears as if it is going to plunge head-first into the water, but then it straightens its head and grasps the fish with its talons. Two forward-facing and two backward-facing toes have sharp spines that enable the bird to clutch the fish. Occasionally an osprey will grab a fish too heavy for it to carry, in which case the osprey might drop it, and try for another meal.

The osprey that nest in northern Illinois in summer spend winters in Florida, Mexico, and South America.

The Illinois Department of Natural Resources is now in the fourth year of their program designed to bring more osprey to the state to increase the number of breeding pairs.

The osprey is the July bird species highlighted by the Forest Preserves of Cook County. Come #birdthepreserves with the FPDCC; view the list of upcoming events for free events near you.


©2016 Chicago Botanic Garden and my.chicagobotanic.org