Space black-capped chickadee houses 650 feet apart, boreal chickadee houses 730 feet apart, Carolina chickadee houses 30 feet apart, chestnut-backed chickadee houses 160 feet apart, and mountain chickadee houses 1 per 10 acres.
Spacing guidance comes from several research papers that have collected data about each species’ territory sites and are based on averages. Actual defended territories range depending on the bird and breeding stage.
Table 1. Five North American chickadee species nesting territory size and nesting heights.
| Chickadee Species | Nest Box Distance | Nesting Height |
| Black-capped chickadee | 650 Feet (average) | 6 Feet (average) as high as 30’ |
| Boreal chickadee | 730 Feet | 10 – 15 Feet |
| Carolina chickadee | 30 Feet | 5 – 10 Feet (average) |
| Chestnut-backed chickadee | 160 Feet | 5 – 15 Feet |
| Mountain chickadee | 10 Acres | 5 – 15 Feet |
Each chickadee species’ territory will also depend on other factors such as the presence or absence of physical barriers and the dominance of the male bird defending his territory. More dominant males will defend a much larger territory (Stefanski, 1967).
Older male chickadees will defend a larger area than younger male chickadees. And when there are physical barriers, this can impact how chickadees defend their territory. For instance, a nesting site backing up to a natural wall may minimize encounters with intruding chickadees.
The stages of breeding period also impact territory. For instance, with black-capped chickadees, during the pre-nesting stage males did begin defending a territory, but during nest-building stage the territory boundaries became more defined. During egg-laying and incubation, the defended territories have been observed to decrease, and then pick back up during nesting and fledging stages (Stefanski, 1967).
Table 2. Regional locations of five North American chickadee species.
| Chickadee Species | North American Region |
| Black-capped chickadee | Northern US, Canada, Alaska |
| Boreal chickadee | Canada, Alaska, some very northern US states |
| Carolina chickadee | Eastern US |
| Chestnut-backed chickadee | Western most US States, British Columbia, Yukon and Alaska |
| Mountain chickadee | Western US, Canada and Alaska |
Why space chickadee nest boxes so far apart
Chickadees, like any other bird will become very territorial especially during the breeding season and will spend a lot of time fighting off competing chickadees to defend their territory. These fights usually involve chasing off competing chickadees but expend a lot of time and energy.
In our observations, we saw female Carolina chickadees actively watching the fights. As the males would flit from tree to tree, mated females would follow on and passively act in defense of the area.
There are also consequences when chickadees fight for nesting territory:
- Bird injuries
- Energy expense
- Time expense
- Delays in nest building
While this video is very difficult to follow because the chase is happening so fast, you will hear the “gargle” vocalizations which are associated with territory defense among other things.
In this case, the chase did not get violent, nor did the other series of chases, but it did buy up a lot of energy.
The primary pair would engage in chasing the intruder chickadee and then take a break for an hour or two. Then the ordeal would continue again for a period of 15 – 30 minutes followed by another rest and then more chases.
Most of the active defense times would happen very early in the morning, just before the sun had risen and continue off and on until about 10 or 11 am (March).
There would be some afternoon chases, and a few evening chases. But most defense activity observed took place in the morning.
To save your chickadees trouble, ensure your boxes are spaced properly. Oftentimes chickadees will find nest boxes along bluebird trails. Birdhouses along a bluebird trail will usually be spaced at least 300 feet apart (if properly set up). In theory, chickadees will find their own proper spacing and set up their natural boundaries.
Despite proper nest box placement, you still might observe chases and fights if an intruding chickadee of the same species comes to investigate a taken territory, as was seen in the video.
It’s also possible that even if you have actively placed your nest boxes far enough apart, there is a tree hole being utilized or investigated by a competing chickadee. This is just part of the process. And you have at least done your part to reduce stress and provide a good home as best as you can.
You may want to check out our article about how to best protect chickadees once they have moved into a nest box. It has a lot of great tips to ensure your chickadees have a successful brood.
What about spacing chickadee houses with other birdhouses like bluebirds?
When pairing chickadees nest boxes with bluebird houses, they will pose little threat to each other if you space the nest boxes at least 25 – 50 feet apart, and make sure the entry holes do not face each other. A good added measure would be to add a 1 1/8-inch hold reducer for black-capped and Carolina chickadees to prevent eviction from bluebirds.
If you have discovered chickadees nesting in a bluebird box, and later find bluebirds interested in the box, hurry and get a 1 1/8-inch reducer on your nest box, and then put up a second box for the bluebirds.
When the second box is not placed at least 25 feet away from the other, bluebirds will end up flittering between both nest boxes and taking more time to defend both boxes as if they’re both theirs. So make sure to space the boxes far enough apart. The more room, the better.
This same advice goes for other birds. Often tree swallows will define a territory. Again, if you come to find swallows interested in your chickadee nest, do what you can to protect your chickadees from invasion, and put up additional boxes.
Beware! House wrens can wreak havoc on nests, poking out eggs and killing young nestlings in order to take over a nest box. However, house wrens are native, which means we cannot remove their eggs or a nest. If a house wren is in your area and you have chickadees, you’ll want to put up a wren guard. You can make these yourself out of cardboard, or purchase them.
If a house wren has begun nesting in a nearby vacant nest box, 25 feet is not enough distance. In this case, our advice is to slowly move the nest box day-by-day further away. Keep a far distance (75-100 feet), but more importantly, try to position the other nest box so physical barriers such as trees or a house block the view of your other occupied nest box.
Do not remove a nest box being occupied by a house wren in the same area as an active chickadee box because that might cause the house wren to get more curious about your chickadee nest.
Chickadees are so little, and passive compared to the bigger cavity nesting birds, that they are just no match. But these other species can nest peacefully if proper space and protection is provided.
Remember, never let a house sparrow or European starling nest in your nest boxes or near your native nesters. These birds kill native cavity nesters and are not protected. The best, and pretty much only way to deal with them is combinations of deterring, and trapping and dispatching.
References
Albano, D. J. (1992). Nesting mortality of Carolina Chickadees breeding in natural cavities. The Condor, 94(2), 371-382.
Black-capped Chickadee. Audubon. (2020, March 31). https://www.audubon.org/field-guide/bird/black-capped-chickadee.
Boreal Chickadee. Audubon. (2020, March 18). https://www.audubon.org/field-guide/bird/boreal-chickadee.
Carolina Chickadee. Audubon. (2019, November 20). https://www.audubon.org/field-guide/bird/carolina-chickadee.
Chestnut-backed Chickadee. Audubon. (2020, January 6). https://www.audubon.org/field-guide/bird/chestnut-backed-chickadee.
Mahon, C. L., Martin, K., & Steventon, J. D. (2007). Habitat attributes and chestnut-backed chickadee nest site selection in uncut and partial-cut forests. canadian Journal of forest research, 37(7), 1272-1285.
Mountain Chickadee. Audubon. (2019, December 16). https://www.audubon.org/field-guide/bird/mountain-chickadee.
Scott, V. E. (1977). Cavity-nesting birds of North American forests (No. 511). Department of Agriculture, Forest Service.
Stefanski, R. A. (1967). Utilization of the breeding territory in the Black-capped Chickadee. The Condor, 69(3), 259-267.
