Wrens in Iowa: 8 Species of These Beloved Small Birds

August 23, 2023

Wrens are not the most celebrated birds, yet these little charmers capture the hearts of many people. Fans of these delightful birds are happy to watch them arrive in the spring, building their nests and nurturing their tiny offspring.

Wrens are widespread across North and South America, and they enchant birders with their cute, round bodies and ball-shaped nests constructed from sticks and twigs.

Identifying Wrens in Iowa

For those eager to spot wrens in Iowa, opportunities are plentiful. While some wrens are year-round residents, others undertake seasonal migrations and are only present for the summer. There are only 5 kinds of wrens that live in Iowa, but there is another that passes through during migration, and 2 more that have been spotted on rare occasions in the State.

Iowa is home to over 433 bird species, and wrens constitute only a small portion of this diverse avian community.

Common Traits of Wrens

What do all wrens tend to have in common?

Most wrens share certain characteristics that aid in their identification:

Small, Rounded Bodies: Wrens typically boast small and rounded bodies, which sets them apart from other small birds like sparrows and finches that tend to be thinner and longer.
Upward-Pointed Tails: Wrens’ tails usually point or angle upward, although they vary in length depending on the species.
Cave-Shaped or Cavity-Dwelling Nests: While not residing in actual caves like their name “troglodyte” implies, wrens build nests in empty cavities, on the ground, or even among aquatic grasses.
Loud and Complex Songs: Wrens are renowned for their vibrant songs, differing from sparrows in both song complexity and dietary preferences.
Insect and Spider Diet. Wrens primarily feed on insects and spiders. Some species occasionally consume frogs, lizards, and plant matter.

Identifying Wrens in Iowa

When identifying wrens in Iowa, pay attention to the following features:

Size: Comparing the bird’s size to familiar species can be helpful, especially because it is hard to estimate weight, length, and wingspan in the field.
Feather Color and Markings: Note any unique markings on the wings, belly, back, head, chin, and tail.
Bill Length and Shape: Wrens typically have pointy bills that may or may not be slightly curved at the end.
Behavior: Observing distinctive behaviors aids in identification. Are they hopping on the ground as they forage for insects? Slamming into other birds that they think are a threat? Hiding in the underbrush of their habitats?
Location and Timing: The region of Iowa and the specific habitat provide valuable clues. Are they in a forest? If so, is it old-growth or new-growth? Are they in tall grasses? In an aquatic marsh? On a rocky hill?
Vocalizations: Listening to their calls and songs is an essential identification tool.

General Tips for Finding Wrens in Iowa

To enhance your birdwatching experience in Iowa, consider the following:

Be Prepared: Research wrens’ appearance, behavior, preferred habitats, and sounds beforehand. That way, you know where to go – and when – to increase your chances of seeing the wrens you want to see.
Optimal Timing and Locations: Plan your birdwatching excursions during peak activity periods and explore suitable locations with dense vegetation. They are most active in the morning and at dusk.
Patience and Stillness: Be patient, stay still, and let wrens acclimate to your presence to observe natural behaviors.
Enhance Your Vision: Use binoculars for clear and steady viewing. You don’t need the most expensive pair of binoculars on the market, but a good pair of binoculars will absolutely help!
Attune Your Ears: Familiarize yourself with wrens’ vocalizations and listen out carefully for their calls.
Observe Behaviors: Pay close attention to wrens’ active foraging habits and hopping movements. If you can get a video, that’s even better!
Utilize Birding Resources: Make use of field guides and birding apps for identification. The Merlin App from the Cornell Lab of Ornithology is especially helpful!
Keep a Birdwatching Journal: Maintain a journal to record essential details of your sightings. This will help you keep track of your sightings and give you patterns to look for later. For example, you’ll likely notice that wrens tend to arrive at the same time most years!
Practice Responsible Birdwatching: Respect the birds’ space and habitats, adhering to ethical “Leave No Trace” guidelines.
Join Your Local Birding Community: Engage with fellow bird enthusiasts for shared experiences and knowledge exchange.

With these tips in mind, embark on a delightful birdwatching journey to spot the enchanting wrens of Iowa!

Year-Round Wrens in Iowa

Only one kind of wren can be found year-round in Iowa: the non-migratory Carolina Wren. Because there are no wrens that come to Iowa for the winter, this is also the only wren you will see here during the winter months.

Carolina Wren

Scientific Name: Thryothorus ludovicianus
Order: Passeriformes
Family: Troglodytidae
Length: 4.7-5.5 in (12-14 cm)
Weight: 0.6-0.8 oz (18-22 g)
Wingspan: 11.4 in (29 cm)

The Carolina Wren is cinnamon-brown with a short, upward-pointed tail and an upright posture. The easiest way to recognize the Carolina Wren is to look for its long, off-white eyebrow stripe that extends beyond the back of its head. They are small and sexually monomorphic, so there are not any differences in the appearance of males and females.

Iowa is on the very edge of the Carolina Wren’s territory. You will really only find them in the southeast corner of the state. They are not usually found north of Cedar Rapids or as far west as De Moines.

This part of Iowa has plenty of its preferred territory, which includes a mix of wooded, shrubby, and suburban areas. Carolina Wrens are also very good at adapting to human environments, including houses, barns, abandoned buildings, playground equipment, and overgrown farmland.

Interesting facts about the Carolina Wren:

Most wrens eat insects and spiders, but Carolina Wrens will also small amounts of fruit.
Their dome-shaped nests are found in a number of different locations, including in trees and shrubs, abandoned shoes, propane grills, flower pots, and more. Their nests are usually found about 3-6 feet above the ground.
Carolina Wrens display an interesting defense mechanism to protect their territory. Males will slam their bodies into hard surfaces like trees. The collision itself makes a loud noise, as does the wind through their wings. This may convince potential predators that the little Carolina Wren is larger than it seems.

Wrens in Iowa During the Summer

There are 4 kinds of wrens that can be found in Iowa during the summer breeding season. These birds will usually arrive in the spring and leave again in the fall. They are the Bewick’s Wren, House Wren, the Marsh Wren, and the Sedge Wren.

Bewick’s Wren

Scientific Name: Thryomanes bewickii
Order: Passeriformes
Family: Troglodytidae
Length: 5.1 in (13 cm)
Weight: 0.3-0.4 oz (8-12 g)
Wingspan: 7 in (17.78 cm)

The Bewick’s Wren has somewhat plain brown coloring, but its flashy white eyebrow stripe is very distinctive. If you are trying to differentiate between a Carolina Wren (which also has an off-white eyebrow stripe) and a Bewick’s Wren, the main difference will be the coloring. Carolina Wrens have a reddish hue to their feathers, but Bewick’s Wrens are grayish-brown. The Bewick Wren’s tail is also quite a bit longer than most other wrens.

Bewick’s Wrens are named for Thomas Bewick, an engraver who was friends with John Audubon.

They can be found in woodlands and shrubby areas in rural, suburban, and urban areas. As long as there is plenty of vegetation, the Bewick’s Wren can make the habitat work. During the winter, they need even more dense vegetation.

Bewick’s Wrens are categorized as rare, inconsistent breeders in Iowa. This means that they are more common in the state than a vagrant bird that has ended up here by accident. However, they are still a very rare and special bird to spot in Iowa!

Interesting facts:

Bewick’s Wren males can sing between 9 and 22 songs, which are made up of trills, warbles, and buzzes. They sing to impress potential mates and defend their territory. Even though they have such a huge range of songs, they still only sing each song for about 2 seconds.
Breeding season males and females will work together to build their nests. Unlike most wrens, which build their nests on the ground or just a few feet above it, Bewick’s Wrens build their nests up to 30 feet above the ground.
In addition to eating lots of insects and spiders, Bewick’s Wrens consume mud and tiny pebbles, as this helps their digestion.

House Wren

Scientific Name: Troglodytes aedon
Order: Passeriformes
Family: Troglodytidae
Length: 4.3-5.1 in (11-13 cm)
Weight: 0.3-0.4 oz (10-12 g)
Wingspan: 5.9 in (15 cm)

The House Wren is very plain, with darker brown feathers on top and paler feathers below. They have very few distinctive markings, save for some light black barring on their wings. They can be differentiated from other common small birds like sparrows by paying attention to their short, upward-pointing tail.

House Wrens are one of the most common songbirds in North America, especially during the breeding season, when they are found from the Pacific to the Atlantic.

They are breeding season residents across all of Iowa. They are found in swamps, forests, and suburban landscapes. Their name conveys one of their common nesting sites: in and around buildings like homes, barns, and sheds.

Interesting facts about the House Wren:

In addition to eating insects and spiders (including beetles, daddy longlegs, caterpillars, flies, and earwigs), they also eat snails. The snail shells give them grit for digestion, as well as calcium.
House Wrens are among the many kinds of wrens that create false nests, although each species does this a little bit differently. House Wren males build a series of loosely constructed nests – sometimes as simple as a few sticks in a birdhouse. Females review the nests and choose one of them to completely rebuild.
House Wrens are opportunistic nesters who will build nests in tree cavities, crevices in buildings, treehouses, playgrounds, birdhouses, and planters.

Marsh Wren

Scientific Name: Cistothorus palustris
Order: Passeriformes
Family: Troglodytidae
Length: 4.5-5.1 in (11-13 cm)
Weight: 0.4-0.7 oz (12-20 g)
Wingspan: 5.9-6.3 in (15-16 cm)

The Marsh Wren is often spotted among the marshy reeds of its habitat, clinging to the tall vegetation. They are mostly brown with a white throat and some black and white streaking on their backs and wings. Males have slightly larger bills.

The Marsh Wren gets its name from its preference for marshy habitats. Males sing bubbly, chattering songs. Their songs may include up to 100 different phrases.

Their diet consists of insects and lots of spiders, which they pick from underneath the leaves of tall grasses and reeds. Less frequently, they fly into the air to catch flying prey.

Marsh Wrens breed across Iowa. Look for them in wetlands that are full of bulrushes, sedges, and cattails.

Interesting facts about the Marsh Wren:

Mash Wrens are non-monogamous, and their nesting habits reflect their mating behaviors. Males build up to 6 false nests for each mate, sometimes numbering up to 22 nests in a territory. Each female will use one nest for incubating eggs and raising young.
Their nests are very strong and attached to the aquatic reeds for stability.
Marsh Wrens are increasing in numbers and are a species of low concern in terms of conservation status.

Sedge Wren

Scientific Name: Cistothorus platensis
Order: Passeriformes
Family: Troglodytidae
Length: 3.9-4.7 in (10-12 cm)
Weight: 0.3-0.3 oz (7-10 g)
Wingspan: 4.7-5.5 in (12-14 cm)

The charming Sedge Wren is rufous, brown, and black with a yellowish wash. The buffy eyebrow stripe is a good distinctive marking to look for when identifying the Sedge Wren. It also has a white eyebrow stripe, an upward-pointing tail, and a short, curved bill.

Sedge Wrens nest in areas with tall grasses, especially sedges, including meadows, marshes, hayfields, and prairies. They have long legs that help them forage on the ground, surrounded by these tall grasses.

They are breeding-season residents across Iowa, which is nestled right in the center of their summer territory. In the winter, they move to the Southeastern US, especially along the coast.

Interesting facts about the Sedge Wren:

Sedge Wrens have somewhat mysterious habits. They tend to be somewhat nomadic, choosing a different breeding location every year. Even if they had a lot of success in a specific spot one year, they may or may not choose that same spot the following year.
They build ball-shaped nests, with the males building several nests for their mates to choose from.
They nest much later than other wrens. Sometimes they will even nest as late as July.
You may be able to coax the shy little Sedge Wren out of the brushes by making a “pshing” sound.

Wrens in Iowa During the Winter

There are no wrens that come to Iowa for the winter.

Wrens That Migrate Through Iowa

The Winter Wren is the only wren that migrates through Iowa between summer and winter ranges.

Winter Wren

Scientific Name: Troglodytes hiemalis
Order: Passeriformes
Family: Troglodytidae
Length: 3.1-4.7 in (8-12 cm)
Weight: 0.3-0.4 oz (8-12 g)
Wingspan: 4.7-6.3 in (12-16 cm)

The tiny little Winter Wren is round and plain. Its unremarkable coloring allows it to hide well among the dense undergrowth. When trying to identify the Winter Wren in the field, look for its silhouette: very small, shaped like a little round ball with a familiar short, angled tail. Males and females look alike.

Winter Wrens live mostly in Canada during the summer. Their winter range includes most of the Midwest and Southeast, although they don’t really go as far as the Florida peninsula. They migrate through most of Iowa, although the southern edge of the state is home to some Winter Wrens during the cold winter months.

Their summer habitat includes areas with dense forested undergrowth. They especially prefer old-growth forests, including deciduous and evergreen forests. They are weak flyers who forest on the ground for insects and spiders.

Interesting facts about Winter Wrens:

Winter Wrens eat huge quantities of insects like flies, beetles, caterpillars, mites, and millipedes. They are great at contributing to pest control! They peck and scratch into the decaying bark of dead trees and fallen logs. large amounts of insects, including ants, flies, beetles, caterpillars, millipedes, and mites. They also eat spiders. They find their food by pecking and scratching into the decaying bark of dead trees and fallen logs.
The globe-shaped nest of the Winter Wren will be as big as the cavity in which it is built. In a small birdhouse, it will be quite small, but if the Winter Wren builds a nest in a large, empty tree cavity, the nest might be as big as a football.
Males build multiple nests, but they put in much more effort than House Wren males. The female Winter Wren has several nearly-complete nests to choose from. Upon picking her nest, she adds some lining made out of feathers and animal hair. The male helps with this task, too.

More Birds in Iowa

We hope you have enjoyed our guide to wrens in Iowa!

Here are some more guides you can use to spot Iowa’s beautiful birdlife:

With these resources at your fingertips, we hope you have great success on your Iowa birding adventures!