Discovery can be intentional, and then it can be complete serendipity. On a brisk, breezy day in early January, I took my labs Pearl and Grizz for a hike on a large public tract of grasslands and wetlands a few miles from my home in northwest Montana’s Mission Valley. Winter (until recently) had been unseasonably mild, and though all the ponds and cattail sloughs were frozen, the ground was virtually snow-free.
One of several Waterfowl Production Areas managed by Montana Fish, Wildlife & Parks in western Montana. This crucial wildlife habitat is contained within the Flathead Indian Reservation.
Not too long into our hike, the more dependable of my pointing labs, Grizz, stuck a classic pointing pose. I approached his mark cautiously to see what attracted his nose and eye. From a dense thatch of sedge, a large, tawny bird with pointed wings burst from the ground and lifted gracefully away with “moth-like” flight. A Short-eared Owl! Five seconds later, a second and third bird lifted off from nearby ground roosts. I managed to snap a couple photos. From my peripheral vision, I spotted another 2-3 take flight to the south. I was as flustered as Pearl, my year-old lab, who has not yet honed the finer skills of pointing. Had we stumbled onto a communal winter roost of Short-eared Owls?
A Short-eared Owl flushes from its daytime roost in thick sedge habitat seen in the foreground.
Another Short-eared owl flies from its roost. The flight pattern is described as deep, slow, with moth-like rowing wingbeats. I would also call it “bat-like” or “buoyant.”
I marched the dogs back to the truck and hiked back to the spot we flushed the owls to do a bit of sleuthing. In a low spot of sedge between islands of cattails I found an area of smallish depressions with concentrated bird poop, owl pellets (mass of undigested parts of a bird's food which are regurgitated), and loose feathers — all the components of a ground roost.
A roost site containing copious fresh droppings, pellets, and shed downy feathers.
Close-up of a fresh Short-eared Owl pellet, closely resembling the original vole!
A delicate contour feather of a Short-eared Owl.
While hiking to another roosty-looking sedge patch, I flushed a single owl, which landed a ways out but within camera zoom distance. Not wanting to disturb the owls any further, I hiked back to the truck across a sparse grassy field thinking owls wouldn’t be roosting there, but bumped into a few more. Given the dozen owls I observed during my hike and the large acreage of the grassland-wetland complex, I guessed there were 30+ Short-eared Owls at this site.
Notice how beautifully camouflaged the owl is with the cured cattail, sedge, and grass vegetation.
A distant glimpse of the grassland ghost.
I’d collected a couple of pellets from the roost, curious at what the owls were feeding on. Pellet dissection and a skull key revealed the owls were feeding on voles, likely the Meadow Vole (Microtus pennsylvanicus) most common to moist, grassy habitats of the Mission Valley.
Fresh Short-eared Owl pellets, about 2-¼ inches in length.
One of the pellets teased apart to reveal the skeletal remains of two voles.
I returned to the site a few times at dusk, watching from the parking area to see the owls leave their roosts. I would see one or two, but not the numbers I saw on January 2nd. Then, just as serendipitously, my partner and I were birding about a mile north of our home this past Thursday and came across a congregation of at least 20 Short-eareds. They were working over some snowy ag fields and roadsides for voles, which brought them within range for observation and photography.
Three amigos watching a 4th amigo fly to the south.
A dusk assemblage of Short-eared Owls.
We see you, but you can’t see us.
Short-eared Owl displaying its namesake short, inconspicuous ear tufts.
The Short-eareds were joined on their hunting grounds by 3 or 4 Northern Harriers. The harriers were quite aggressive towards the Short-eareds and among themselves. I observed an altercation between a harrier and owl resulting in the theft of the owl’s prey item by the harrier – very similar to this amazing action photo captured by Choruser & Bucketeer Jeff Graham in western Washington.
Northern Harrier (on the far left) food and habitat preferences overlap with Short-eared Owls on both breeding and wintering ranges. Harriers routinely practice “kleptoparasitism” on the owl.
I was surprised to see an owl that typically lives, roosts, and nests in open terrain using spruce trees for winter perching and roosting. But it was cold and windy on Thursday, and the dense spruce likely offered protection from the wintry elements as well as a safe space to catch a few winks. Reading up on their winter roosting ecology, as little as 2 inches of snow will cause Short-eared Owls to move to nearby conifers for roosting, and heavy snowfall can result in them abandoning winter roost sites altogether.
This Short-eared Owl (a recognizable whitish-morph) was ‘King of the Hill’ of this spruce.
I was also surprised at the notion of a Short-eared Owl winter colony of so many individuals. I was vaguely aware of communal winter roosts of modest numbers (<10 individuals) in the Midwest and Eastern U.S., but my impression was of much lower densities in the west. I’d surveyed for Short-eareds in Idaho in 2007 and surveyed two grids in 2014-2015 for the Western Asio flammeus Landscape Study, but these efforts were focused on breeding ecology and so few nesting pairs were documented. So witnessing a winter roost of 30+ Short-eared Owls was astonishing in an intensely good way!
A stiff, freezing wind ruffles some feathers.
A dead vole in the clutches of a Short-eared Owl. Notice the beautiful creamy color of the owl’s feet.
Look at the beautiful gift I just horked up for you! You’re welcome. Looking at the tufts and facial feathers, this owl has the look of a 1st year bird.
Short-eared Owl catching a few winks before dinner time.
I am encouraged, too, by a note in the Cornell Lab of Ornithology’s account of the Short-eared Owl that “when food is plentiful, winter areas often become breeding areas.” There is a glut of voles and field mice in the Mission Valley – more than I’ve seen anywhere in my life. The Short-eareds Owls are welcome to partake of the rodent bounty and nest safely in our back 40 with our deepest gratitude.
For further reading:
Audubon: Short-eared Owl
The Owl Pages: Short-eared Owl
Owl Research Institute: Short-eared Owl Conservation / Owl Research Institute: Short-eared Owl
Thanks to Grizz and Pearl for pointing me to an amazing moment in nature, one I won’t soon forget!
Good dogs.