Nesting Behaviors of Nuthatches in North America

In North America, four species of nuthatches can be found: the white-breasted, the red-breasted, the pygmy and the brown-headed nuthatch. 

Nuthatches have a ‘work smarter, not harder’ attitude when it comes to nesting. They nest in pre-existing tree cavities, often those excavated by woodpeckers, securing a predator-free area to raise chicks. 

A win-win for the nuthatch. A safe place to nest without expending lots of energy. Now that’s smart. 

Read on to discover more about nuthatches and their unique nesting behaviors.

An Introduction to Nuthatches

Nuthatches are small, plump birds, no larger than a chickadee and somewhat resembling a woodpecker. They can be found in deciduous and coniferous forests. 

Besides the red-breasted nuthatch, which, you guessed it, has a striking red breast, other nuthatch species across the US and Canada bear resemblance to one another. 

They typically have an off-white underbelly, with blue-grayish plumage on top. Most have a distinctive black stripe on their head. 

Although hard to spot in flight, their distinctive foraging behavior makes these birds relatively easy to identify from the ground. 

Unlike treecreepers, which only move upwards on a tree, nuthatches can traverse both up and down the tree with ease.

What follows is how this species gets its common name. 

Once a food source is located, often large nuts or acorns, the nuthatch will jam it into crevices within tree bark. By continuously hammering the wedged nut or similar with their sharp beak, they effectively “hatch” out the seed from within.

Nesting Behaviors

Right, into the nitty-gritty of nesting behaviors. 

Each species of nuthatch in the US and Canada display slight variations in nesting behaviors. 

So, we’re going to break them down by species.

1. Red-Breasted Nuthatch 

A common sight at feeders, red-breasted nuthatches are a small and active species found across all of North America. 

Although they are found across North America, they only breed in the Western mountains of the USA and woodland in Southern Canada. 

Like all nuthatches, the red-breasted nuthatch is a secondary cavity nesting bird. 

And, whilst using the cavity of a previous tenant is a great way to save energy, they are in hot demand. 

To reduce competition from conspecifics, the red-breasted nuthatch collects resin globules from pine trees and smears it around the entrance of their nesting hole. 

Like a builder using a plastering trowel, this bird uses tree bark to apply the sticky resin. 

Males plaster the resin around the outside, whilst females coat the inside of the nesting cavity. The natural adhesive coating prevents any unsuspecting intruders from getting into the nest. The red-breasted nuthatch, on the other hand, can dive straight into the hole without covering themselves with the resin. Clever. 

If this tactic doesn’t work, the red-breasted nuthatch actively chases away other secondary cavity nesters that stray too close to its nest.

2. White-Breasted Nuthatch

Another common garden feeder, the white-breasted nuthatch is an energetic bird with an appetite for insects. 

In late-winter, courtship displays begin. 

To attract a female, a male raises its head, spreads its tail feathers and begins a series of sways and bows. If a female likes what she sees, copulation will begin and the pair may mate for life. 

The white-breasted nuthatch has a tendency to nest in old woodpecker cavities. However, when secondary cavities are limited, it may excavate its own nest. This is energetically costly, and can take a female up to 18 days to create. 

Once a suitable cavity is found or created, the female will begin building the nest from within. Using a variety of natural materials, such as pine needles, animal fur, grass and shredded bark, she’ll line the cavity ready for egg laying. 

To ward off predators, both male and female white-breasted nuthatches have been observed sweeping noxious insects close to the entrance of their cavity. The chemical secretions given off by the insects help repel predators. 

3. Pygmy Nuthatch

The pygmy nuthatch takes the crown for being the smallest nuthatch species in the whole world. 

Yet, despite its small size of just a few inches, it is an incredibly active bird. They are mostly spotted racing up and down the trunks of ponderosa pines across mountainous regions of Western North America.

Due to their small size, it isn’t uncommon to see up to 15 pygmy nuthatches roosting in the same cavity. 

They are cooperative breeders, meaning more than two birds help with the rearing of chicks from one nest. For pygmy nuthatches, an additional 1 – 3 helpers can often be observed. 

Oftentimes, helper pygmy nuthatches are the breeding pair’s own offspring from the previous years. 

The helpers defend the nest from predators. To do this, they may sway threateningly from side to side, or even cover the cavity entrance with their own body to minimize detection. The helpers also feed the incubating females and chicks. 

Another function the helper birds carry out is the facilitation of nest excavation. Whilst they can create their own cavities, pygmy nuthatches often alter and adapt existing holes. 

Once a hole is excavated, both the male and the female, sometimes assisted by their offspring from previous years, will bring lining materials such as bark fibers, plant down and feathers.

4. Brown-Headed Nuthatch

Found only in the Southeastern pine forests of the U.S, the brown-headed nuthatch has a distinct rubber duck-like call. 

This small bird shares traits with other nuthatch species. For example, they can excavate their own nests from the soft, rotting wood of trees. These cavities are usually no higher than 10 feet off the ground. 

If suitable nesting sites are not available, the brown-headed nuthatch will successfully nest in artificial nest boxes. 

To waterproof these nests, they fill crevices with plant material, such as leaves and grasses. 

The brown-headed nuthatch is also a cooperative breeder, enlisting the help of helper birds, typically younger males, to help raise and care for the young. 

In the breeding season, these birds are fiercely territorial. Being monogamous, potentially remaining with one partner their entire lives, pairs readily defend their nest against potential threats.

Final Thoughts

Nuthatches, though similar in appearance, have adapted their nesting behaviors to the environment they’re nesting in. 

Some species, such as the red-breasted nuthatch, use pine resin to ensure the safety of their nests. 

Other species, such as the pygmy and brown-headed nuthatch, enlist “helpers” to increase chick survival rates. 

Whilst most nuthatch species choose to nest in cavities formed by other birds, such as woodpeckers, they can also adapt to nesting within artificial bird boxes. 

So, to increase nesting success rates, add a bird box and a feeder to your backyard.