Three of a Kind-- Communal Roosting by Pacific Wrens

It’s fascinating when a species so common that we take it for granted surprises us from time to time. Here in Victoria, BC, Canada, Pacific Wren (the bird formerly known as Winter Wren) is a daily occurrence anywhere there is suitable habitat. This species is best known for its amazing torrent of song and equally impressive talent for staying well-hidden in the forest understory. Imagine my surprise when I discovered a Pacific Wren roosting on an open ledge right above the back door in my carport. Starting in the winter of 2006, I began to notice droppings next to the stairs, and knew that something was roosting there at night. Treading lightly and using a small flashlight, I discovered an unidentifiable ball of fluff tucked into one of the corners of the ledge. After several attempts at taking photos, sneaking surreptitious peeks during the night and, eventually, accidentally flushing it by arriving home at just the wrong time, the bird was finally identified as a Pacific Wren. I was delighted to share the carport and immediately made new house rules: No loud noises in the carport after dusk; only sneaky peeks at the bird to check on its welfare (and to show it to friends, of course!); and tolerance for the ever-increasing accumulation of wren droppings. Bird nut? Who, me?


This screen grab, taken from video recorded using an infrared wireless video camera, shows three Pacific Wrens huddled together. Notice that the outer birds are facing the edge of the ledge, while the middle bird is faced the other direction with its tail hanging over the ledge.  

Each winter, the wren (or a lookalike) would return to the roost, only to depart when the allure of breeding pulled it away for the summer. On the stormiest and coldest nights, though, it was conspicuously absent. Worried about its survival, I’d check the roost only to find it empty. There was more than one occasion that I thought for certain that it must have died, only to see new droppings a few days later when the weather settled down. It must have had a warmer, more protected spot for those colder nights.

In February, 2009, this species surprised me yet again. One night, I lit up the roost to see if the wren was there and found not one, but TWO wrens on the ledge. Wow! I wondered if this was a pair and if Wren One had brought Wren Two to the ledge as part of its courtship. As luck would have it, I had recently purchased an infrared wireless IP camera which was quickly repurposed to be a wren-roost spycam. I mounted it in the carport that day while the wrens were away and got set for an evening of discovery. My placement of the camera was poor, and all I got were some grainy, difficult to see images, but enough to determine that there were not two wrens, but THREE!! Communal roosting! Who knew?! Well, it turns out that some people did know (as many as 31 found huddled together in a nest box in western Washington in December 1924), but this was exciting news for me. I repositioned the camera and for the next week or so, spent several hours a day reviewing the nocturnal adventures of the wrens. Here’s what I learned 

Pacific Wrens are very itchy birds. Before settling (and I use that word loosely) down for the night, a wren can spend several minutes scratching, fluffing, preening, scratching, picking, scratching, and then more scratching. When it is anticipating others, it looks for them. The first wren to the roost would lean over so that it could see under the beam, watching for the roostmates to arrive. A similar posture was taken when the wrens departed in the morning. When one wren took off, the others would lean over the edge and watch it go. The party really started when all of the expected tenants had arrived at the roost. I like to call it “Three Wren Monte” (video link). The birds hopped, fought, and clambered over each other to determine who got to sleep where. It appeared the most desirable spot was the one in the middle, with the bird’s tail hanging over the edge of the ledge. More on that later. Of course, this spot would be the warmest and most protected, so procuring it was worth a little bickering. The birds lined up head to tail; the typical arrangement involved the outer birds facing out, and the lucky middle bird facing in. Once the positions had been set, the three birds would all fluff up and form a ball of feathers the size of a large orange. I’ve seen photos of other roosting birds, and it’s amazing how the fluffing can turn a bird into something unrecognizable. Good idea if you’re sleeping among the enemies! This was my first view of communal camouflage.

A good night's sleep was not in the cards for these wrens. About every half hour or so, someone had to answer a different call of nature. When it was the middle bird, whose tail was already hanging over the ledge, there was no problem. A slight stretch and “plop”, the deed was done. However, when it was one of the outer birds, chaos ensued. The bird would have to turn around, disrupting the orb of warmth, much to the dismay of the ledgemates. Then the shuffling, scratching and a new game of three wren monte would begin again (Nature Calls video link). I can’t say if there was any rhyme or reason as to who got to be in the middle for the next shift, but it appeared that at least some of the time, positions were switched.

Morning departure was much more leisurely than I expected. The wrens awoke around first light, then spent up to half an hour getting ready for their day (The Morning Routine video link). Stretching, scratching, fluffing, preening, hopping around the ledge, more scratching … did I mention that they are very itchy birds? When the first wren would finally decide to leave, the other two would hang from the edge of the ledge to see where it went. Within a couple of minutes, the others would follow, leaving the ledge empty for the day.


This wren appears to be sneaking a peek a the camera, perhaps attracted to the red light or some noise. 

It’s been two years since I recorded the antics of these three wrens on my carport ledge, but the roost is still occupied. This year, I have seen one or two wrens roosting in the usual location,  but I’m not sure that either of them is one of the original birds. The Bird Banding Lab (2011) shows the longevity records for Winter Wren to be just over five years. That bird was released alive, so it is presumed ot have lived at least a while longer. My suspicions about the current tenants are due to their behaviour. Wren One was very tolerant of my comings and goings, and rarely woke up because of my activities or my flashlight. When I’ve checked the roost this year, I’m almost always looking at the face of a wren looking back at me. They stay put, though, so while aware of me and perhaps a bit nervous, they seem to understand that they are relatively safe where they are.

Things I've learned about the roosting habits of Pacific Wrens:

* Pacific Wrens sometimes roost communally in the winter.

* They are loyal to their roosts, but have more than one for different weather conditions. My carport is excellent protection against predators and rain, but not so great for extreme cold.

* They seem to be able to communicate with each other about good roost sites, and may even pass them along to the next generation.

* They are aware of changes at the roost site. They looked directly into the camera on several occasions, even in the darkness. One climbed up on wiring to have a closer look. Either they could see the red glow of the infrared lights, or otherwise detected that a new object (the camera) was there. It didn’t seem to bother them, but they were aware.

* They “talk” to each other at the roost. I recorded high-pitched squeaking sounds that I haven’t heard from Pacific Wrens in the field.

* They look for each other during arrivals and departures.

I love that familiar birds can still teach us new things. There’s always a reason to keep watching!

All videos and still screen grabs recorded by Ann Nightingale

Lost Art? Revisited: Alternatives to Taking Notes

Our recent piece, entitled Lost Art?: Writing Descriptions of Rare Birds, has generated a fair amount of interest among those who serve on records committees and review eBird reports. Several of these folks have recommended this article to others and posted links to it on personal blogs, statewide listservs, and other birding forums to which they subscribe. Given the scattered distribution of the article, audience feedback has not been centralized or limited to the comments posted directly to BirdFellow. 

As the author of the piece, I have a predictable interest in all the commentary and response that the original piece has generated, so I've been doing some surfing. As one might expect, some respondents are still not that excited about writing descriptions, even if they appreciate the value of doing so. The general theme of such feedback ranges from, "I don't want to have to carry a notepad into the field" to  "I don't have time write a long description of the bird" or "I just want to go birding, I don't want to exchange time spent in the field for time stuck inside documenting the rarities that I find." Believe me, if you fall into one of these camps, you are not alone. Even those of us who do carry notepads and attempt to take detailed notes would much prefer to just keep birding rather than stop to make notes. Worse yet, we don't want to spend time crafting accounts that describe what we saw last week instead of being out birding this week!


Using a standard ink pen (you might want to carry a pencil), I produced this sketch of the head of a Yellow-bellied Sapsucker (a "review" species in Oregon) that I saw on 12 february 2011. This bird is an immature male, still showing much of its juvenile plumage. A sapsucker that still looks like a juvenile this long after it hatched, is by default a Yellow-bellied. My primary focus in drawing a sketch was to show that the bird's head pattern was mottled and did not have the strong black-and-white pattern one would see on an adult. This sketch and a couple others will accompany the written description that I send to the Oregon Bird Records Committee. 

Here are a couple of ideas that might make life easier for you. If you can't obtain a usable photo or don't carry a camera, perhaps you can draw an image that tells the story more quickly than you can by writing it down. Okay, I know, your next excuse is that you have the artistic talents of a cucumber. I feel your pain on that one, especially since I live with one of the more talented bird artists in the country (Shawneen Finnegan Art). Thankfully, artistic talent is not a prerequisite when it comes to producing a useful sketch. If you struggle to get birds in proper proportion or shape, I recommend checking out a helpful primer, which demonstrates how to create rudimentary bird sketches. It is published online by Mike Patterson. If you click on the photos at the bottom of the page at Mike's link, you'll find three easy-to-follow animations that show you how it's done. 

Alright, so you still don't want to draw or take notes. Have you ever considered carrying  a modest digital voice recording device in the field? I know folks who do this and they swear by it. Presuming that most of us talk faster than we write, it's safe to assume that we can verbally describe a bird faster than we can in writing. Imagine having a recorded dictation of what you saw in the field. In addition to describing field marks, size, and shape, you could easily include commentary that explains how you eliminated similar, more-expected species. When you finally sit down to write your report to a records committee, a real time recording captured during the observation will surely jog your memory and help you recall important details. If you own a cell phone, chances are it has some capacity to make video/audio recordings. Even if it is only capable of recording short--20-30 second--snippets (like mine), a few short recordings can be compiled into a reference that will come in handy later when you write up your report. If you still don't want to write or type, you can convert these recordings to digital wav files and send them on to your local rare bird review body. 

As stated in the original piece on this topic, I am a firm believer that any process which requires you to stop and think about what you are observing will ultimately make you a better observer. I've yet to meet the birder who is not striving to improve their skills in this regard. You don't have to be looking at a rare bird to practice and hone these skills. Just for fun, take a few minutes and try to sketch an American Robin or write a thorough description of one without referencing a field guide or looking at the one eating berries in your front yard. Did you remember to include the blackish streaks on the white undertail coverts?

Tail-Propping Chickadees: A Cold Weather Strategy?


This Black-capped Chickadee was one of several that seemed to thriving in the sub-zero temperatures at Wisconsin Point in February 2011. 

It was a brisk February morning here in Duluth, Minnesota, so I decided to go birdwatching over in Wisconsin to check out the local winter-dwelling gulls. While I was at Wisconsin Point, I encountered a group of high-strung Black-capped Chickadees. They were flitting from seed cluster to seed cluster, just inches above the ground. On this particular morning, occasional wind gusts were driving the wind chill down to between    -25F and -30F, causing me to wonder how chickadees or any bird can endure such conditions. To say it was humbling to see these little troopers out in the bitter cold, would be an understatement. They apparently manage to survive these elements by using their fluffy layer of insulation to conserve the warmth generated by constant feeding and the resulting metabolic processes.

As I marveled at the fortitude of this little flock of eight chickadees, I noticed that while feeding many of them were using their tails for support--touching the ground almost in a woodpecker fashion. They would cling to stems/stalks of grass, pull their legs in (presumably to retain heat) and use their tails as a crutch, or brace to keep them upright as they picked through bent-over seed heads. 


Note that the only points of contact between the ground and these Black-capped Chickadees are their tails. Since there is no flow of blood or other bodily fluids through feathers, there is little if any opportunity for precious heat to be lost through the tail.


I have never heard of chickadees or any other perching birds engaging in such behavior. Various woodpeckers and Brown Creepers regularly exhibit somewhat similar behavior to this, using their tails as a brace, or support as they climb vertically up the sides of trees. When moving up trees, woodpeckers actually open their feet up to let go of the tree for a split second and then pump themselves up the tree using their stiff-shafted tail feathers. 

Going back to the chickadees, it was certainly neat to witness this interesting adaptive behavior. I was unable to find any other accounts describing this type of behavior in Black-capped Chickadees. 

Editors Note: We'd like to thank Erik for sharing this wonderful photo essay. As for the pinkish blush on the underparts of these birds, we can't offer an explanation. Perhaps a member of the BirdFellow community can provide the answer. If you've observed chickadees, or other birds using this tail-propping strategy in cold weather, we'd love to hear about it in a comment. 

All photos by Erik Bruhnke