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Species profile: Finding the Flammulated Owl
Nocturnal, quiet, and tiny, the Flammulated Owl can be maddeningly hard to track down, but if you’re lucky, one might just find you
Published: January 1, 2006  The Flammulated Owl breeds across much of western North America and winters as far south as Guatemala.
Many of my birding friends, the ones who still haven’t seen the elusive and diminutive species after years of frustration, think this an egregious omission. Some actually believe Otus flammeolus doesn’t exist — that it’s just a little joke professional ornithologists play on amateur bird enthusiasts.
The species account in The Birds of North America proclaims that the Flammulated Owl is “perhaps the most common raptor of the montane pine forests of the western United States.”
This will come as a shock to every birder who has stumble-stepped through night-dark woods, hooting and listening for Flams without hearing or seeing one. I can attest to the tiny owl’s existence because I have photographs, but I can relate. Flammulated was one of the last North American owls I saw, and it was certainly the most frustrating to find.
A Flam is hard to locate for several reasons, but the challenge begins with its voice. Most birders spot owls after hearing them first. Good luck hearing a Flam. The male’s primary call — a single, soft, low-pitched note to advertise territory generally transcribed as boo — is repeated, sometimes endlessly, every two to four seconds.
The calls, which sound like shorter versions of the Long-eared Owl’s hoooo, supposedly travel up to 800 yards. Yeah, right. Maybe under perfect conditions on a calm night. Besides, the hoots are ventriloquial, and the amplitude is lowered whenever intruders are detected in the territory.
The owl’s ability to produce such a low-frequency sound is quite unusual because small owls generally have higher-pitched calls. But specialized structures in the Flam’s syrinx “make the calling of this small owl as impressive as possible,” as ornithologist Alden Miller put it. The net effect is that a Flam is always much closer than it sounds, and its location is nearly impossible to pinpoint.
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An owl the size of a sparrow
Bird: Length
Flammulated Owl: 6.75"
White-throated Sparrow: 6.75"
Fox Sparrow: 7"
White-crowned Sparrow: 7"
Golden-crowned Sparrow: 7.25"
Harris’s Sparrow: 7.5"
How small is the Flammulated Owl? Measured from bill tip to tail tip, it’s about the length of a White-throated Sparrow. Other familiar sparrows are longer.
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Smaller than sparrows
Of course, if you do happen to pinpoint that location, you’ll be trying to see a small owl. Really small. Only our Elf Owl is smaller. Flams weigh less than our two pygmy-owls, and — picture this — they are smaller by length than several of our sparrows! Their preferred habitat is open ponderosa pine forest with an oak understory. Now picture reddish orange ponderosa bark and remember the common name, Flammulated, is derived from the Latin word flammeus, meaning flame-colored.
Our owl has enough rich rufous highlights in its facial disc and along the scapulars to blend perfectly into the reddish interstices of its chosen tree. Tiny owls, huge trees, perfect protective coloration: Do you still wonder why Flams are heard more often than they are seen?
Limiting your chances further, Flams are strictly nocturnal and most active in the hour after sunset and the hour before sunrise. (Translation: You have to be in the woods after dark.) They live between 5,000 and 10,000 feet above sea level. (This is no backyard bird.) Flams have dark eyes. (Your flashlight won’t reflect off their iris.) Their preferred daytime roost is the densest vegetation they can find. (Are you feeling lucky?) Flams are thought to be colonial nesters. (Large tracts of seemingly appropriate habitat go uninhabited.) And the owls are highly migratory, giving you only about a six-month window to see them in North America. (Look and listen from late April through October.)
Flams nest from southern British Columbia to Mexico, withdrawing in winter to Central America. Little is known about their migration except that it takes place at night. Migration certainly correlates to Little Flame’s evolution as a 100-percent insectivorous species. Typical fare includes nocturnal moths, beetles, crickets, and grasshoppers — prey that does not survive winter in the high country of North America. It is thought that migration in September and October follows the mountains, but the return in April, when insects are still scarce at higher elevations, passes through lowlands and valleys.
In breeding season, owls are typically found in pine/oak woodlands, but they will utilize aspen and fir in northern states. In southern Arizona’s sky islands, they may occur in lower montane canyons with Elf Owls. Flams are monogamous. Males return before females, typically to the previous year’s territory, though nest sites are generally not reused.
Favored sites are old woodpecker holes in pines or natural cavities in dead snags in the oak understory. Reproductive rates for Flams are lower than other owls — two to three eggs per clutch — but breeding success rates are high for such a small bird. Squirrels prey on nests; avian predators on adults are the usual suspects: owls and accipiters.
As recently as 1980, the Flammulated Owl was characterized as “rare and local.” What, you don’t believe anything has changed? Take heart. The first half-dozen times my wife and I went looking for Flams, we heard and saw zero. On our seventh try we were successful... sort of. After getting a response to our calls, we spent half an hour trying to locate the owl amid tall pines when a bear interrupted our efforts. We didn’t see our first Flam that night.
But don’t fret. Sometimes Flams find you. The following July, we were camping in the Bradshaw Mountains of central Arizona, and Flammulated Owls were the furthest thing from our minds. It was 10 p.m. The pines were dripping after a crackling monsoon thunderstorm. Green beetles with cream antennae were pinging off our lantern, and shadows of branches played through the light. Suddenly, one of the shadows became shape and intersected a beetle’s flight on silent wings. My flashlight beam followed the wraith to a horizontal bough, where it landed. Flam!
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Eye-opening facts
Researchers continue to learn about the Flammulated Owl. Recent discoveries:
Monogamy: Extra-pair copulation, in which a bird “cheats” on its mate, was documented in the species 15 years ago — a first for all owl species. But new DNA analysis shows that males rarely successfully fertilize females other than their own mates. The intense role that males play in parental care may account for this so-called genetic monogamy.
Lifespan: Banding results from Colorado indicate that male owls can live at least 14 years, females at least 8 years.
Dispersal: Adult Flams tend to return to the same site each year, and they maintain pair bonds for up to four years. But few young owls return to their hatch site to nest as adults. Instead, they disperse to find their own nesting sites. Their dispersal appears to contribute to healthy gene flow within the species’ “highly interconnected metapopulation.”
Nest holes: Flams typically nest in old woodpecker holes. Owls in New Mexico prefer Northern Flicker cavities over those of Acorn Woodpeckers. In northern parts of its range, the owl relies on Pileated Woodpecker holes.
Nest boxes: In a Utah forest with no pines, Flammulated Owls consistently nested in nest boxes. A five-year study documented 34 nests, 22 of which produced fledglings.
Watch List: Partners in Flight lists the owl as one of the 100 birds on its “Watch List” and estimates its global population at 37,000. Because no trend data exists for the species, the group considers the number a “guesstimate of very low precision.”
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Closer than ever
Smaller, lower, and closer than we had ever imagined, the owl plied its trade around our campsite for half an hour, oblivious to our presence. We learned a lot about Flams that night. If you’re really close, you’ll realize the call is actually two-noted: boo-BOOT.
Prey is located visually and captured on the wing in beak or claw or hover-gleaned from pine needles and branch tips. Flam wings, like those of our daytime flycatchers, are relatively long and pointed, which facilitates hovering but limits maneuverability. This, in turn, would seem to account for Flam’s preference for open forest.
Here’s more hope: Since that night we’ve encountered several Flams, all when we were actually looking for them. Doesn’t it always seem that once you’ve found an elusive species you intuitively know better how and where to look? Remember, this is “perhaps the most common raptor of the montane pine forests of the western United States.”
Know also that research indicates Flams are more plentiful in wet weather cycles. More insects, more Flams. This is important information for you non-believers. The 10-year drought in the West appears to be over, meaning Flams should be easier to find now than in recent years.
Raise your hand if you’ll be out there looking.
That’s what I thought.
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