A great singer, the house wren is widespread in North America and South America, reaching the tip of Tierra del Fuego in Argentina and Chile. A breeder in the upper two-thirds of North America, the house wren is feisty and aggressive not only to other house wrens but also to other bird species, even those larger than the wren itself. This article is intended to aid in identifying house wren nests and eggs.
House Wren breeding facts
| Breeding Period | Early May through late August. |
| Nest type | A cup surrounded by coarse nesting material. Cup typically sits on a base of sticks. |
| Substrate & Location | Nests are always built inside a natural cavity close to the ground or in nesting boxes. |
| Cavity: | Any type of cavity. House wren also nest in crevices and anything that resembles a cavity, such as hanging boots in a shed. |
| Nesting Activities | The male starts building the nest by first making a base platform made of sticks and then building the nest over it. The female builds the cup and finishes the nest. |
| Egg Description | Pale densely marked with tiny reddish-brown or cinnamon brown dots. Dots are more concentrated on the broad side of the egg. |
| Egg Length and width | 0.64 in x 0.5 in. |
| Egg-laying | It begins a day or two after nest completion. Females lay one egg every day. |
| Clutch size | Typically 4-7 eggs. Clutches of 3 eggs or 9 eggs are rare. |
| Number of broods | Two broods per year. |
| Incubation Period | Typically 13 days, ranging between 12-15 days. |
Breeding range
The house wren breeding range encompasses roughly the upper two-thirds of North America from coast to coast. Wrens spend the winter months in the Southern U.S. and move back north to the spring and summer breeding range. The map showing the breeding range indicates the regions where house wren nests and eggs are expected.
The range map (right) shows where the house wren is expected to breed. Source: allaboutbirds.org.
Habitat
House wren favor semi-open habitats where they forage in bushes, thickets, hedgerows, and the understory of forest edges primarily within 20 feet from the ground. Wrens can be found in rural areas, low-density urban areas, and suburbs with enough vegetation and nesting sites.
Migration and social behavior
The house wren is a short-distance migrant. The breeding grounds encompass roughly the upper two-thirds of North America, which is not far from the wintering grounds in Southern U.S. and Mexico.
House wrens arrive in the breeding grounds beginning in the second week of April through mid-May. After breeding, wrens migrate back to the wintering grounds starting in the second week of September through the first week of November.
Upon arrival to the breeding grounds, males are rather vocal, singing loudly and persistently. Conversely, during the fall migration, birds stop singing, and it is difficult to tell the exact dates when wrens leave the breeding grounds. It is unclear whether house wrens migrate in flocks or individually.
Social Behavior
House wren form pairs and defend a territory only during the breeding season. Pairs then split up and return to the wintering grounds, where they have a quiet and solitary life.
Wrens are known to return to the same breeding territories year after year. Although they form new pairs once they arrive in the breeding grounds, some pairs likely meet at the same breeding territory to pair up again for the breeding season.
Breeding Period
After pair formation and nest building, females begin to lay eggs as early as the first week of May. By mid-May, most breeding house wren are laying eggs. However, wrens that winter in higher latitudes and higher elevations may start laying eggs later.
The first eggs laid begin to hatch by the last week of May. Young wren may still be seen near their parents as late as the last week of August.
House wren nest appearance
House wrens build round nests with a central cup. Unlike bird nests built by other birds, male house wrens first build a base of sticks that supports the nest. This base of sticks is unique among cavity-nesting birds and can be used as a reference to identify a house wren nest.
Because house wrens are cavity nesters, it is difficult to assess the nest shape.
Hose wrens nest in cavities and enclosures of different shapes and sizes. They adapt their nest to the available space, ensuring that the nest cup and depth are consistently the same sizes. The size and shape that surrounds the nest cup may show a good deal of variation.
Nesting habits
House wrens are cavity nesters but cannot excavate their cavities. They use a variety of existing cavities or cavities excavated by woodpeckers.
House wrens can also use crevices at buildings and are creative in finding structures for a nesting site. Wren nests have been found inside hanging boots, flower pots, nestled in tools in sheds, in parts of parked cranes and other machinery, and even in the pockets of clothes hung to dry.
House wren readily take nesting boxes. A study on nesting house wrens found that in areas where natural cavities and nesting boxes were available, house wrens preferred breeding in nesting boxes.
Breeding house wrens typically reuse the same nest when they attempt a second brood. Depending on the state of the old nest, the male may only make repairs and replace the nesting material.
Conversely, when the nest, particularly the nest cup, has been heavily utilized and is soiled by the earlier brood, the male proceeds to take most of the nesting material and rebuild a new nest with fresh material.
Ornithologists suggest that replacing the nest material helps clean the nest from parasites that could be detrimental to the next brood.
Nesting site
Male wrens arrive first at the breeding grounds to find a suitable nesting site and territory. The male then proceeds to claim the nesting site by building a platform made of sticks. The male may build more than one nest.
When females arrive at the breeding grounds, they visit territories and inspect nests prepared by the males. If the female approves of the nest, she stays and begins to continue building the nest. This action by the female indicates that the pair have been formed.
House wren are notorious for divorces and mate switching. Most pairs (73%) attempt a second brood in a single breeding season.
For reasons that remain unclear, some females leave their mates and move on to find a new male with a new nest and territory. Males left by females stay in the territory and pair up with available females looking for males.
Nest building
House wrens have a stereotyped nest-building process. When a male finds a nesting cavity, he first brings sticks into the cavity creating a base or platform.
Potential female mates arrive in the breeding grounds a few days later than the males and inspect nesting sites and territories. If she approves of a nest site and territory, she stays with the male and begins to construct the rest of the nest over the base of sticks built by the male.
The female then builds the cup and lining before beginning laying eggs. The male may assist the female in bringing her food while she is diligently gathering nesting materials.
Egg appearance
The house wren eggs are oval-round in shape with an approximate length of 0.64 in and a breadth of 0.5 in.
The eggs are pale and thickly spotted with tiny reddish-brown to cinnamon-brown dots, denser on the egg’s broader side. There is little variation among eggs within a clutch.
Overall, house wren eggs may vary across nests. Some have fewer dots and may appear to have less dense markings than others. The color and dotting pattern is similar.
The nest and eggs of the Carolina wren are rather different.
Egg Laying
Egg-laying begins soon after the female finishes lining the nest cup. Once the female starts laying eggs, she lays one egg every day in the early morning hours.
The female house wren starts laying eggs as early as the first week of April. The initiation of the egg-laying period varies with latitude, and it is generally later in higher and colder latitudes.
Clutch size
House wrens in North America typically attempt two broods every breeding season. The clutch size for the first brood early in the nesting season ranges between 4 to 7 eggs. Clutches of 3 eggs or 9 eggs are rare.
Clutch sizes for the second brood are smaller on average, ranging between 5 to 6 eggs.
Studies comparing clutch sizes in natural cavities and nesting boxes found that house wrens tend to lay larger clutches in nesting boxes. As indicated above, house wrens chose nesting boxes over natural cavities when both were available.
Incubation of the eggs
Once the female starts laying eggs, she spends some time in the nest and often applies some heat to the eggs. She spends more time in the nest as she lays more eggs.
The female starts incubating the eggs when she still has two to three eggs to complete the clutch. Only the female develops a brood patch and does all the incubation. She takes breaks outside the nest to eat and do other needs. The male delivers food only sporadically during the time the female is incubating.
Incubation period
The female house wren incubates the eggs alone, typically for 13 days. In higher latitudes, higher elevations, and colder temperatures, the incubation period last longer. Overall, the incubation period ranges between 12 to 15 days.
References:
- Brawn, J. D. and R. P. Balda. (1988a). Population biology of cavity nesters in northern Arizona: do nest sites limit breeding densities? Condor 90:61-71.
- Drilling, N. E. and C. F. Thompson. (1988). Natal and breeding dispersal in House Wrens (Troglodytes aedon). Auk 105:480-491.
- Dunn, E. H. (1976c). The relationship between brood size and age of effective homeothermy in nestling House Wrens. Wilson Bulletin 88:478-482.
- Johnson, L. S. and W. A. Searcy. (1996). Female attraction to male song in House Wrens (Troglodytes aedon). Behaviour 133:357-366.
LEARN MORE ABOUT BIRD NESTS AND EGGS:
Excellent article! A Wren just built a Winter Nest in the Wreath on her
front door! Should she provide bird seed during the cold months in
North Carolina?
Thank you!
I had a bird build a nest in a ealmart sack on top of a storage container. Not sure what kind of bird though.
Hello Sandy,
Some people say that birds nesting in your home is a blessing.
Describe it for us if you get to see it.
Good luck,
Al
Hi Pat,
Yes, it is a good idea feed birds throughout the winter. Studies have shown that it helps them through the coldest periods.
Wrens are more likely to eat suet. If you offer suet, no only wrens but other birds are likely to visit your yard attracted by the suet.
Do you happen to have photos of the nest you can share?
Thank you,
Al
We have a house wren that made her nest by smartly squeezing through a gap in the siding on our house and made her nest inside the eave of our house. (Sandwiched between the wood and vinyl siding.) I can hear the young ones chirping and moving around on the siding. It’s great stepping outside and being surrounded by the beautiful calls of wrens. I find their basically ball shape with a head stuck on amusing and it’s a joy to watch them land in our front window hedge with an insect in it’s mouth. They never seem to go straight to the nest but will fly to a ‘staging’ area in order to avoid giving away the nest location to predators.
Hello Tom,
That’s great. I have a pair of woodpeckers using my bird house located right outside my office window…It is the best distraction I’ve ever had!
Al.
Thank you for the great information! We have a couple cheap dollar store bird house my mother was going to throw out. I took them and used them for decoration on my patio. About a month or so ago i noticed a house wren going in one of the houses. Jump forward to yesterday 7/12/22. We have babies! I was so surprised and excited!
Hello Kim,
I sense the excitement. I would too! Those are such little things that make birds fun.
Regards,
Al
Great info! We have a nest in a hanging flowerpot on our patio. Curious location because it is very close to where we frequently sit. We’re concerned for the eventual fledglings because we have 3 dogs. One of them has caught a few birds. We would like to put it in a safer spot but we’re worried they won’t know where it is. We’re really not sure what to do to help ensure their safety.
Hello Donna,
Please do not move the nest to a different location, it will be abandoned.
I would recommend monitoring the nest activity and perhaps keeping the dogs indoors or monitoring closely when the chicks are about to fledge. If enough bushes are around, the chicks will get there and perhaps will not be noticed by the dogs. It would be a problem if one chick falls on the floor where the dogs would notice it and catch it.
Good luck,
Al.
I think I found a wren nest underneath a window on the front of our Central Coast California house. We were away for a month; we came back a week ago, and this morning I was pruning a tangle of penstemon, pulling out a clutch of stems I’d severed at the bottom, where the foliage was brown, and accidentally pulled out a nest. There were three eggs with the powdery rust or mauve coloration in the photos you show here. I tried to tuck the nest back into place, putting some of the cut foliage around it, but I had already removed a lot of what was hiding it. Was this an abandoned nest (it is now July 30)? Or was it still a place where eggs were being incubated?
Ellen,
If the nest had eggs, it perhaps was active. The parents may resume incubating or if much changed around the nest they may abandon it. It was an accident and I would not worry much about it. Wrens can start another nest and brood in two weeks; they lose their eggs all the time.
Regards,
Al.
We have had wrens in two decorative bird houses. They have had 2 sets of eggs each summer. Last week the second set hatched but vanished about 3 days later. We noticed dad was feeding the babies every 3 minutes. No coming or going. And we know when the birds hatch because their chirping gets louder every day.I don’t think a raccoon or snake got them cuz the house would have been knocked down. Any ideas
Jean,
I suspect that a snake is more likely to have predated the nest. Racoon typically nock down or partly destroy nest. Snake leave nests intact. If the house-nest is till up I can’t think of other predator.
Al.
Last year we found a nest in our carport and my husband have been so careful to protect it from the cats. One day he noticed the little birds were just flapping around and making such a terrible racket but the cats weren’t outside. When he climbed up and looked in with a flashlight it scared him half to death to find a snake in the Box.
Hi Tracy,
Yikes, unfortunately it happens with some frequency. I would have thought that nesting in the carport would offer some protection to the nest. If you live near natural habitat, chances are snakes are going to be present too. Snake predation on bird nests ranks among the highest causes of nest failure, but is normal. The parents will renest, perhaps at a separate location since they known now that a snake found the nest.
Good luck.
Al
I live in western New York State. I have a wren’s nest in a ceramic holder that hangs on my front porch. I noticed it about 3 weeks ago. When do the babies emerge from the nest? I hear them, but do not see them.
Hello Mona,
Sorry about the delay. Baby Carolina Wrens will start leaving the nest about 14 days after hatching, or earlier.
I hope your birds fledged safely.
Al.
I have two wrens that snuggle up together on a ledge under my porch roof- there’s no nest. They come at dusk every evening, and I don’t see them during daylight hours. Have you ever seen this before? I can’t get very good photos because of the lack of light, but I could send you a few. I’m so curious about this!
I am in Southwestern Ontarioand had wrens nest in the summer. We are prepping our yard for winter as the temperatures have significantly dropped. Today we went to clean out the nesting can the wrens used and found 4 unhatched and intact eggs. We don’t recall seeing the adult wrens in at least a month. Will the eggs still hatch? Should I leave them and the nest in place? Need some advice please. I do have a picture if that would help.
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My house wrens have come back to a nesting box I have on my deck, for many years. This year, there is a red bellied woodpecker at my hummingbird feeders, and the wren is very territorial with it, I believe because the woodpecker preys on the wren eggs. It seems like the male stands guard over the box. Is this true?
Hi Libby,
It is possible that woodpecker can harm the eggs of other birds. This is more likely if the eggs are in birdhouse. However, I would thing that the entrance hole of the house wren’s house is too small to allow a woodpecker in.
Good luck
Al
We have a house wren nest. It is busy every year and it’s hanging over our covered patio. We put a piece of tin about five inches wide around the post That would be likely for snakes to climb and get up there. They cannot go over pieces of tin. So no problem. Today we saw the 1st batch of 5 babies out on the patio. Where do they go when they leave the nest because we never see them again
Hi Carolyn,
Great idea, putting tin around the post. That works great. PVC pipes can also do the job.
Yes, young birds, including the Carolina Wrens, do not return to the nest once they leave it. The first couple of weeks after leaving the nest, they remain in the vicinity being fed and assisted by the parents. Then, the become independent and begin to venture further away.
They make faint noises to communicate with the parents and remain in thick vegetation where they are difficult to see.
Regards,
Al
Should a wren remove an egg from the nest? I found a broken egg on the ground. The nest is deep in a large clay pot.
Hello Allison,
House wren can do that. It may be a neighboring (Competing) wren not the owners of the nest.
House wrens tend to hurt nests of other birds within or near their territories. Not sure why the would
do this.
I hope the rest of the eggs hatch.
Al.
Such a wonderful article! We have a nesting box right next to the patio that the bumbles would call home for the last 7 years. This year we witnessed the male claim it the same time the bees were trying to get comfortable.
It’s was definitely entertaining to hear his constant singing in search of his mate. So excited to to see what happens next!
Hello Dona,
This sounds interesting! Who kept the house?
Keep us posted.
Al.
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Hello, We have a Carolina Wren that nests on our front porch every year. We are in Central Florida. I was doing some fall cleanup on 11/19 and went to check the bird house and clean it and was surprised to find 4 unhatched eggs in the nest. Is mid to late November where I am too late for hatching?
Hi Tonya,
Yes, it is late. Those eggs may an clutch that was left unhatched?? Did you see the parents incubating?
Al.
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Accidentally moved a hanging flower pot that had an active wrens nest in it with 4 eggs. 1 egg fell and broke. I put the hanging basket back where it was. Will mama come back??? She was squawking at me the whole time. That’s the only reason I realized what was happening.
Hello Mary,
I believe she (the pair) will come back and continue incubating the eggs, if the pot was put back at the same location with the nest entrance facing on the same direction prior to the disturbance. The fact that one egg broke should not make a difference.
I would like to learn what the birds did after you put the pot back.
Good luck,
Al
Thank you, Al. I saw them come back and once again there at dusk, but unfortunately the next morning the nest was in my yard (no longer in the hanging pot) and no eggs in it. Do you think they destroyed it or a predator ?
Hello Mary,
If the nest was removed the way you describe it, it appears that a predator was the culprit. Raccoons and opossums tend to torn nests apart and take the content.
Sorry,
Al
A wren built a nest in my hanging basked of fake autumn greenery. She laid 5 eggs that all left the nest last week, and she’s back and laid 3 more yesterday. The eggs all had very few small brown spots except for one in the nest now. It’s a bit bigger and has a lot of brown spots. I’m not sure what’s happening here!
Hello Matlene,
Could it be a cowbird egg? If you suspect that is the case, you can safely remove the bigger and different egg gently using a tea spoon.
Good luck,
Al.
A wren has built a nest outside our front door in a plastic wreath. She has 4 eggs, one hatched, but the baby somehow fell out. We picked it up with a tissue and placed it back in the nest since it was still moving, although likely was injured by the fall to the concrete. Not sure if that was the right thing to do. Any thoughts?
Good morning. We moved into our new house a month ago and I hung one of my homemade hand-felted birdhouses outside my new office window. I now have house wrens nesting. It’s been fun watching them build the nest and now I think she is actively sitting. He seems to show up and sing loudly in the morning hours. It’s gratifying that they enjoy these wool felt nesting boxes!
Hi. Im new to birds. I have a nest newly built by not sure what type of bird. After googling I found out the egg color is exactly the same as a wren’s. The nest is almost like a perfect cup and sit atop of my fiddle-fig tree around 7ft tall. Can someone help me to confirm whether its a House Wren nest or not? Thanks
Hello Jazlan,
Given the shape and location of the nest, it is not likely to be a wren nest. Wrens build dome-shaped nest with side a side entrance in cavities or hidden places. I am working on a egg identification guide what will be helpful in situations like this.
You can monitor the nest for 15-20 minutes and see what bird goes in and out of the nest.
Good luck,
Al.