House sparrow nests are usually found in nest boxes or other types of cavities and are constructed using various nesting materials such as straw, grass, feathers, litter and fiber. Other characteristics of a house sparrow nest are its size and tunneling architecture.
Identifying house sparrow nests and nesting behavior is very important in North America because they are a nonnative invasive species on this continent.
To be more specific, not only are they a nuisance at birdfeeders, their colony and flocking behavior means they transmit diseases to other birds faster. They are also known for routinely killing native songbirds for their nesting sites.
We have a helpful video that shows how to differentiate house sparrow nests from other native songbird nests. One of the most helpful aspects of this video is its visual aids.
Identifying a house sparrow nest
You’ll typically find house sparrow nests in decorative birdhouses (avoid using decorative bird houses), nest boxes, crevices, dryer vents, hardware store pallets, building signage and other cavities. This behavior is what classifies them more commonly as cavity nesting birds.
Though less popular among house sparrows, nests can sometimes be found in open settings and in rafters.
When identifying a house sparrow nest within a nest box or birdhouse or other cavity space, indicators will include inconsistent nesting material, nests filling the cavity interior almost completely, and a tunnel from the entry hole/port leading into the nesting chamber.
Inconsistent material
An incredible thing about birds is how consistent each species is in terms of construction material and architecture.
For instance, robins will build their nests out of dried grass, pine needles, twigs and mud, forming a neat, rounded out nest cup in an open location.
Bluebirds will build their nest out of grass, or pine needles forming a neat cup in a cavity space such as a tree hole or nest box.
Chickadees will build their nests with a mossy base, peeled bark, and line it with a layer of fur atop a neatly rounded cup inside a cavity space.
And house sparrows are consistent in how they build their nests, but when it comes to nesting material, there is usually less uniformity.
When opening a nest box with a house sparrow nest, you’ll find a good amount of grass or straw or pine needles. But you will usually find a lot of other material included. Listed below are material you may see in a house sparrow nest, and each house sparrow nest will vary in material distribution and location (no layering or lining).
- grass
- straw
- hay
- pine needles
- leaves
- feathers
- twigs
- litter – plastic, wrappers, etc.
House sparrow nest structure/architecture
Each species of bird will have a specific style or structure they use to build their nests. Many have types of birds will build the iconic nest cup like robins and cardinals.
House sparrows build tunnel style nests where their nest will dome inside a cavity with nesting material surrounding the entrance and leading down into a nesting chamber where the eggs can be found.
This is actually one reason a front-opening nest box is ideal, because it give you access to the entry tunnel and down into where the eggs are.
When you find a nest in your birdhouse or nest box that is not made of a uniformed material and has a tunnel structure that leads from the entrance down to a deeper area of the nest, there is a good chance this is a house sparrow nest.
But this doesn’t fully confirm that you have a house sparrow nest, and we will get into that a little more further in this article.
House sparrow nest height
House sparrows typically fill the nest box almost entirely. You may discover a small gap between the ceiling of the nest box and where the nesting material actually stops. But otherwise, it’s a pretty full nest box.
And this is unlike other birds like chickadees and bluebirds whose nesting material usually stops short of the entry hole.
What makes it hard to identify a house sparrow nest
We have a great resource that helps you compare a house sparrow nest to bluebird nests. And in it, we describe in detail scenarios that will make it hard to identify a house sparrow nest. You can learn more by visiting that article.
But to make it simple, a house sparrow nest can be hard to identify when the nest is still under construction, when the material within is actually very neat and uniformed, when a bird is building a nest on top of another nest, or when it’s not actually a house sparrow nest.
In most of these situations, the combined key indicators will help point you in the right direction. However, the absolute best way to figure out if you have a house sparrow nest or not is to spend a little time watching the nest to see what type of bird is bringing material to the box or singing on top of the box.
This is so important because Carolina wrens are an example of a little brown bird that builds a dome/tunneling nest out of inconsistent material. They are not classically cavity nesters. Carolina wrens are actually famous for building their nests in the most random, odd places. But, occasionally, they will build a nest in a nest box. And since they are a native bird (also super sweet), their nests must remain protected and unharmed.
House sparrow nesting information: eggs and stages
House sparrow eggs are very small, the size of larger jelly beans. They are typically a grayish brown color with a lot of dark speckling.
A female house sparrow will usually lay one egg a day until she has about 5-7 eggs in the nest. Once all of the eggs are laid, she will begin to incubate the eggs for 10-14 days.
Once the eggs hatch, nestlings will remain in the nest for about 14-16 days, and then fledge the nest – or take their first flight. Once a baby house sparrow leaves the nest, they don’t return, but the parents do look after it and help teach it how to survive.
One of the things about house sparrows is that they are very efficient at reproducing. Once one round of hatchlings have grown up and taken their first flight, a female house sparrow will waste no time working on her next brood (set of babies).
House sparrows can have about 2-3 broods in a single year. But this count can vary depending on location and environmental conditions.
House sparrow conservation status in North America
House sparrows are a nonnative, invasive species in North America. Their classification as invasive means they are the cause of ecological harm in North America by spreading diseases, infesting grain products and fatally attacking native songbirds, both adults and nestlings.
House sparrows, Eurasian tree sparrows and European starlings are not federally protected. Most states do not protect them either; however states may vary in their conservation approaches toward managing these invasive birds.
We do want to mention that Eurasian tree sparrows are protected in the state of Illinois.
For the most part, trapping and euthanizing these invasive birds is encouraged in order to help native songbirds rebuild their numbers and thrive.
We’ve put together a resource that goes into more detail about methods of euthanasia as well as passive methods (not directly euthanizing house sparrows and starlings) of managing invasive birds.
While these tips will help guide you better in identifying a house sparrow nest, you’ll find that your experience will empower you to identify these nests almost without thinking.
