Photo ©
Lee Pauser
By Robyn Bailey, NestWatch Project Leader
When longtime NestWatcher Lee Pauser wrote to ask about some curious observations of Nuttall’s Woodpeckers, I tried to shed some light on the mystery by doing what I usually do—looking for answers in the scientific literature. I knew my search was going to be a short one when the authoritative source Birds of the World introduced their entry on Nuttall’s Woodpecker with this statement: “Remarkably little has been published on [their] nesting biology.” I was surprised when I further read that their incubation period was estimated (at 14 days) from one nest. No nest predators have ever been documented, and no estimates of nest survival exist.
A Hole New Home
A male Nuttall's Woodpecker pauses at the entrance of a nest cavity. In this species, males are responsible for excavating the nest cavity.
A Dearth of Data
One reason for this deficit of information is their very limited range. Nuttall’s Woodpeckers are almost entirely confined to oak and riparian woodlands of California, with a small extension into the Baja California peninsula. Moreover, they usually nest in cavities that they excavate around 16′ off the ground, making it very challenging to observe their nest contents. But here is where Lee had a unique advantage—since 2008, they have been occasional occupants of nest boxes he placed for other birds such as titmice, bluebirds, and nuthatches. Even with this close-up view, watching their nesting behaviors did more to raise questions than answer them.
For example, among his 20 nests containing a total of 48 eggs, why did just a single nestling fledge between 2008–2024? Why did the majority of these nests end with eggs simply vanishing? One possibility is predators removing the eggs. Another possibility is that a nest box competitor removed the eggs. Other NestWatchers have reported successful Nuttall’s Woodpecker nests in nest boxes, but the rate is low (31% success in nest boxes). Outcomes for nests in natural cavities (of which there are 24 in our database) are generally unknown, and as mentioned previously, no published nest survival estimates exist with which to compare our nest box rate.
Not The Usual Nest Site
In May 2024, this female Nuttall's Woodpecker was spotted in one of Lee Pauser's nest boxes with at least 3 eggs. It's unclear why she is not incubating the eggs.
Deadly Serious
Another unsettling question that came up was why Lee sometimes found dead adults or young of other species (e.g., Violet-green Swallow, White-breasted Nuthatch) in the same or nearby nest boxes. Are Nuttall’s Woodpeckers deadly serious about nest defense? The literature is silent on this matter, but we do know that Red-headed Woodpeckers will destroy and evict the eggs and nestlings of other species nesting nearby. Sometimes the eggs and young are consumed, but other times not…perhaps to clear the area of competitors for food? While Nuttall’s Woodpeckers have been noted to chase away other birds from their nesting area, Lee’s intuition is that they are capable of deadly force. The clues are there, but hard evidence is lacking.
A Rare Glimpse
This Nuttall's Woodpecker nestling in a nest box offers a rare glimpse at this life stage.
Let’s Solve a Mystery
Information on the nesting habits of Nuttall’s Woodpeckers is lacking, but NestWatchers can help. The NestWatch database contains 57 records for this species, but 32 of those represent nests in nest boxes. Nest boxes are easier to monitor, but the frequency of these nests is an overrepresentation of that nest site choice. Most Nuttall’s Woodpeckers prefer natural cavities, and it can be misleading to draw conclusions about a population of woodpeckers based on these rare instances of nest-box nesting.
Nevertheless, observations of natural nests are exceptionally difficult to make, and we shouldn’t disregard the data from nest boxes. In fact, this is a good opportunity for NestWatch monitors to use nest cameras to elucidate what might be going on in these nests. NestWatch also welcomes any historical datasets for archiving, which are clearly needed for this species. Even anecdotal photos and videos of nest predators would be helpful to learn more about them. The nesting habits of Nuttall’s Woodpeckers remain a modern mystery, but it is one that we can solve together with the help of citizen science.
Last year I had a Nuttall’s woodpecker excavate a nest in an old dead walnut tree snag next to my house in Northern CA– the snag is obvious in winter but covered with wisteria vines in the spring. The young successfully fledged (I know one for sure). They excavated two holes– an entrance and an exit. Super secretive and interesting birds!
Hi! I’m excited to hear about the interest in Nuttall’s Woodpeckers. We lived in Nichols Canyon in Los Angeles for 35 years (we left in Feb 2023), observed them in our property, and heard their calls across the canyon. I have photos and notes about a pair that frequented some Silver Dollar Eucalyptus trees on the north side of our house and a pair that made a nest hole in a burl of a very mature Blue Gum Eucalyptus tree on the west side. It’s not clear if they are the same pair, but one or two were always around. I have seen a third male and a territorial interaction. I’ve meant to put the complete information and photos in eBird, but have only sporadically done so.
The nest hole is about 10′ above the patio level and the tree is next to a frequently used hot tub. The first time I noticed the nest hole, there were noises coming from inside. While I never saw a fledgling leave the nest, I did see one on the east side, where there is a natural-looking waterfall with shallow pools that is popular with all kinds of birds. Both parents came and went for feeding, but the male was most often near the nest and cleaning it.
The following year, a Bewick’s Wren occupied the hole and I did see parents coming and going, but again, if fledglings were successful, I did not see them leave the nest nor did I see parents attending to them outside.
The third year, Nuttall’s nested again and I did hear sounds from it. This time I am not aware of seeing any fledglings, but they were in there for some time. I never saw any nest preditors or dead woodpeckers.
During the fall and winter, the male returned daily around dusk to sleep. First, he would noisily move among the adjacent silver-colored Eucs and Pepper trees, then to the Blue Gum. He continued calling as he moved around the tree until he felt like going in. I often waited for him, standing quietly less than 10 feet away. Before disappearing into the hole, he would sit on the edge, look at me, look in the hole, look at me, and so on. He definitely knew I was there. Sometimes my husband would be in the hot tub, but that didn’t bother him either. Once in a while the female would show up and call also, but not as insistently as the male. This behavior went on for at least 3 years after the first nest sighting. There may have been another nest attempt, I’m not sure.
There is more to tell, but I keep very busy with family and work and never seem to have the bandwidth to get the material together. I will put this on my calendar for the fall and try to post everything, going back maybe 10 years.
P.S. There was a call for information about Allen’s Hummingbirds a few years ago. I have observations of 2 nests and a chubby female who dominated one of our feeders to share… there are some notes in eBird, but I have notes that predate the mobile apps. And there are a bunch of them at our current house in Northridge/Los Angeles. There are notes on them in my eBird account. Anna’s and Black-chinned also.
Hi Sharon, Thanks for sharing this information. If you’d like to contribute nest record data, you’ll need to report this information to NestWatch – we aren’t able to glean any nesting data out of eBird as its stored is a completely separate database. Please take a look at our overview page for more information on our project, and read this FAQ to learn how to report data for a nest. Thanks!
RE: “This behavior went on for at least 3 years after the first nest sighting. There may have been another nest attempt, I’m not sure.”
I should have said it went on for at least 6 years–but I need to go through photos and notes to be sure of dates.
I believe there was at least one nest in Crescenta Valley Community Regional Park. I’m new to birding and I happened to run into a skilled birder while walking my dog. She showed me where they were at. I used the Merlin app to ID their calls. On a walk later that month, I saw a black colored bird make a nest in a hole on a branch ~ 8 feet up. It was in the same area as the Nuttall’s woodpeckers. When I went back to check on the nest it was empty and the other bird spices wasn’t sited. I haven’t seen that species in that area since. I have seen the Nuttall’s woodpecker recently (July).
We used to have Nuttalls Woodpeckers nesting in our neighborhood in Palo Alto, CA in the early 1990s when we lived there. One year they were nesting in a silver maple a little ways down the street and the male Nuttalls would come to our yard during the day and spend time in a hanging bird feeder that we had in a tree in the front yard that was unoccupied. I figured he was pooped from taking care of the chicks and taking naps in there or perhaps just shirking responsibility–haha. We saw him come and go several times. One time when I was showing it to a friend, I opened it and he was in there!
One time I saw him go in and then the female go in and then the box jumped around and the male exited. We used to laugh about that, saying that she made him go back and do his part in taking care of the chicks.
I forgot to say that the Nuttalls would peck out the opening of the hanging box in our front yard and at the beginning of the next nesting season we would put a square of wood with the proper sized hole for chickadees and they would peck it out again and use it for roosting– this happened several years in a row.
I live in an oak woodland area in the low Sierra Foothills. The remark above about an entrance and exit hole is interesting. We had a Nuttalls make an extra hole in our bluebird nest box but it never moved in. Funny though the bluebirds very regularly used it as the front door and exited out the front door.
For several years we had a few nuttalls visiting our back yard, along with regular sightings of a red-bellied sap sucker on an old Chinese elm and the year-round acorns. Haven’t seen the nuttall for at least three years, and the sap-suckers for one. Will be keeping an eye out for the nuttall return.
A Nuttall regularly visits a huge oak tree in my backyard in Redding Ca.