August 10, 2022

The clouds are glowing lavender and gold as the sun climbs over the Big Belt Mountains this morning. The spring chorus of meadowlark song that floated across this pasture a few months ago has fallen quiet now. But in the distance, closer to Sevenmile Creek itself, over a hundred black-billed magpies are flocking, perching along the fenceline and gliding down into the grasses. 

My fellow birder and Last Chance Audubon Society volunteer, Stephen Turner, has joined me here this morning to renew a five-year-old tradition. Since 2017, Prickly Pear Land Trust has given us special permission to conduct bird surveys here, on their Sevenmile Creek property. It’s a beautiful 350 acres with a variety of habitats: pasture, grassland, and over a mile and a half of stream. It’s also the site of a major stream restoration project, and public access is currently restricted to occasional volunteer workdays and educational tours.

Restoring a degraded stream and the important habitats along it is no small task. Since the start, it’s been a community effort, led by Prickly Pear Land Trust, with many folks working together to bring this project to fruition. For the last five years, Stephen and I have been fortunate to be a part of this, making detailed observations of the birds here and learning how they respond to restoration.

Sevenmile Creek bird surveys

Each survey we do here is a close look at the birds. Which species are present today? How many of each? And what are they doing? Our route is always the same, starting in the pasture where we’re now standing and following the stream for over a mile through different restoration zones. We begin near sunrise and continue birding for as long as it takes to get a thorough picture of the birds here on our survey day. And because birds fly – some of them for thousands of miles – what we see is always changing. During the summer, these surveys can take a long time. Some of them have lasted for eight hours. And we’ve done a lot of them. Since we started in 2017, this morning marks our 187th survey.

Doesn’t it get boring to walk the same route again and again? Surprisingly, no. Each survey adds another layer to the stories this place has shared with us. The more we bird here, the richer our experience is. On every survey now, we walk past the place where a peregrine falcon caught and ate a magpie in 2017. We pass the section of stream where the bank swallows nested in 2019, the great horned owl’s favorite perches, and the pond where we found a migrant blackpoll warbler in the spring of 2020. Already, we’ve accumulated volumes of these stories. Every shrub along this creek holds bird sightings and memories.

Each season here has its general patterns – but still, no two days are the same. Just like a good TV series, each new episode paints a more interesting picture. So as we get ready to start our birding today, it’s with a sense of anticipation. What will we find this time?

The pasture 

The air is mild and still this morning, just cool enough for a light coat. We’re standing in the closely-grazed pasture where we begin our surveys. Sevenmile Creek is a distant band of darker vegetation to the north. Today, Stephen is recording the bird data. Already, he’s noted the weather and started his timer. We’re both wearing binoculars, and I’m carrying my camera. Our eyes and ears are ready. It’s time to get started. 

We don’t have to wait long. To our east, we hear the sharp “electrical sparks” call of an eastern kingbird from a Russian-olive. Below it, a large, elongate lump is perching. As we raise our binoculars, we can see rusty barring on its belly. It’s a long-tailed bird, larger than a robin, with a blocky head. This is a Cooper’s hawk: a stealthy, bird-hunting raptor. No wonder the kingbird is scolding it. 

Interpreting the patterns

Having five years of bird survey data is a huge help when it comes to understanding what we’re seeing today. Over these years, we’ve never found Cooper’s hawks nesting here. But they stop over regularly in the spring and fall, trying to ambush small songbirds as they migrate through. Wherever this hawk spent the summer, it seems that its migration has already begun.

It’s surprisingly early in the fall to see a Cooper’s hawk here, though. In past years, our earliest fall-migrating Cooper’s hawks have passed through Sevenmile Creek two weeks later than this. So is today’s raptor just an atypical one, starting its migration extra-early? Or could it be a Helena-area bird that nested somewhere else nearby and is wandering around the valley, not quite migrating in earnest yet? 

It’s hard to encounter a hawk like this one without wondering about it. Where has it come from? Where’s it going? What is its life like? Every bird we see here has a story. Through these surveys, we can see the general patterns of their lives. Take migration, for example: we can literally see it happening as birds show up one week and are gone the next. But what fascinates me most is what we’ll never know. This Cooper’s hawk experiences the world in ways that we just can’t. But by being here this morning, we can get a small glimpse.

Phoenix from the ashes

As we get closer to the stream itself, we move from the closely-cropped pasture to an ungrazed area. Here the smooth brome is knee-high. Hundreds of grasshoppers leap away from us as we walk. Dry grass seedheads drop off as we pass.

It’s hard to tell now, but almost the entire restoration site and its surroundings burned to the ground two years ago. It was a hot afternoon in early September of 2020. Strong winds pushed a wildfire through the dry grasses, leaving a blackened moonscape in their wake. And although the grassland has recovered quickly, the shrubs along the stream still bear the marks of the fire in their blackened, dead branches. There, too, new shoots have grown back impressively from the charred aftermath. But for the shrubs it’s been a major setback, and it will be a few more years before they recover fully.

The Cooper’s hawk is no longer in the Russian-olive. Where has it gone? We scan our surroundings and we manage to spot it again. Now it’s perching in a chokecherry along the creek, the branches killed in the 2020 fire. The same eastern kingbird has followed the hawk and is calling vigorously over its head. The raptor takes off, heading northeast, low. In the instant before it flies out of sight, we see the kingbird leap into flight and dive-bomb it.

More hawk drama

The hawk is hidden by shrubs for just a few seconds. Then it suddenly changes course and it’s back in the open, flying quickly upstream. Now there are two eastern kingbirds chasing it, calling explosively and diving repeatedly. After about a hundred yards, the kingbirds land in a dead alder. The Cooper’s hawk continues on. Why have the kingbirds stopped? Maybe they’re still defending a breeding territory, with fledged young nearby. 

Once in a great while, we can hear a western meadowlark singing faintly in the distance. A pair of far-off sandhill cranes start making their resounding calls.

By now we’ve seen six eastern kingbirds in this area. As we had suspected, it seems that they’re a family group with fledglings. We’re getting close to the stream now, so we turn west, walking up the drainage towards the continental divide. From here, our bird survey route will follow the creek.

As we get closer, the Cooper’s hawk flushes again. And the kingbirds have decided they’re not done with it yet! Two of them flutter into the air and chase it another 200 yards upstream, diving at it again and again. As the kingbirds finally peel off and the hawk lands, a small group of magpies take off with a harsh chatter of alarm. For a predator that hunts from ambush, this hawk isn’t having a good morning.

To our right, near the stream, we hear a Bullock’s oriole chattering. Then we see her (no black throat, so this is a female) flying into a dead alder. There she’s joined by a yellow warbler. These are two species that are closely associated with deciduous trees and shrubs, often along streams. Usually we see them in much denser cover than what this dead alder is offering. We’ve reached Sevenmile Creek.

Sevenmile Creek: the lush tangle

The restoration of the stream has progressed in phases, and now we’re standing in the most recent one. Five years ago, the creek was in bad shape here. It ran through a deep ravine – nine feet deep in places – where only a few shrubs were able to find a toehold. During spring’s high water, muddy runoff sluiced through this ravine. Without a floodplain where the waters could spread out and soak in, the torrent would tear at the crumbling banks that flanked the channel, carrying mud downstream. It wasn’t just a problem in terms of erosion and degraded habitat. The channel also acted like a high-pressure hose, funneling the energetic stream farther down into the Helena Valley, where it added to the risk of flooding in residential areas.

But thanks to restoration work, this channel has changed drastically in five years. In place of the old ravine, the stream now meanders gently across a new floodplain. When the contractors excavated this new channel, they filled in most of the old one. But cleverly, the design called for leaving several short sections of it open. These quickly filled with groundwater and became a string of small ponds, mimicking the habitats that beavers create along streams like this one. In just the past five years, right where we’re standing now, Sevenmile Creek has gone from a degraded ravine to a meandering stream, connected to a lush floodplain dotted with small ponds.

Replanting Sevenmile Creek

But all good things take time, and the restoration work in this section is only a year and a half old. If we look hard, we can spot the native shrubs that the contractors planted last spring, hiding here and there in their little tree protector cages. There are hundreds of them: chokecherries, silver buffaloberries, alders, snowberries, and more. In a few years, with luck, they’ll be providing shade and food for birds and fish. 

But right now, they’re hidden among the luxurious growth of shorter-lived plants that have responded to the spring rains that watered the soil disturbed by the excavators. The floodplain is rank this year with the growth of kochia (Kochia scoparia) and the piercing vanilla smell of white sweetclover (Melilotus alba) in bloom. Between the patches of kochia and sweetclover, there are swathes of intermediate wheatgrass (Agropyron intermedium), a perennial that will soon outcompete these early colonizers. 

Last spring, several volunteers helped me scatter seeds of a variety of native plants in this newly-restored floodplain. 2021 was a tough year for seedlings: the summer was hot and extremely dry. But among this year’s exuberance of weeds, we can see occasional clumps of Rocky Mountain beeplant (Cleome serrulata) and showy milkweed (Asclepias speciosa), two of the native plants we seeded. In spite of the drought, the planting project added to the habitat diversity here. With luck, these plants will continue to thrive. And perhaps in a few years, the milkweed plants will expand to become a large, monarch-supporting patch like the one I visited earlier this summer at West Mont Farm and Gardens.

Grasshoppers in the weeds

Now I notice a row of fat, two-striped grasshoppers (Melanoplus bivittatus) lined up on a mullein stem (Verbascum thapsus), where several Hunt’s bumblebees are flying from flower to flower. These grasshoppers are abundant today in the floodplain.

When I think of excellent bird habitat, this rank, weedy stand of kochia and sweetclover isn’t usually what I imagine. But in spite of that, it’s still structure and cover – and with all of these grasshoppers, there’s lots of food in here right now.

And the birds are unquestionably using this habitat today. Savannah and vesper sparrows are all over the floodplain. We can hear their lisping calls all around us and see them darting past. Once in a while, we manage to get a better look.

These two grassland-nesting sparrows can be hard to tell apart – especially at this time of year, when there are juveniles around. Both are streaky, well-camouflaged songbirds. But the vesper sparrows have a noticeable white eyering – plus white outer tail feathers, which they flash conspicuously as they fly. Savannah sparrows, on the other hand, lack the white tail feathers, and they often show a yellow smudge in front of their eye. 

Birds of the floodplain

Now that the eastern kingbirds have chased the Cooper’s hawk away, the kingbirds are chattering and foraging here. They leap into the air in pursuit of insects, then quickly return to their perches in the kochia and other weeds. 

Earlier this summer, we saw multitudes of red-winged blackbirds spread out across this habitat, singing from territorial perches near the ponds and the stream. That bustle of dozens of males spreading their red shoulder patches and singing konk-a-ree is gone today. Now the blackbirds are in a noisily chattering flock, mostly made up of streaky brown females and juveniles. As we continue upstream, they flush from the grasses and fly past us, making emphatic kak calls. 

We wade through the jungle of floodplain vegetation to the end of a small pond and peer over it, looking for ducks and shorebirds. But we don’t see any. A Savannah sparrow is foraging near the water’s edge. A common yellowthroat makes its rough chak call from the cattails. The growth of these cattails has been incredible – who would guess that these ponds only showed up here a year and a half ago?

The magpies are still talking from the fenceline, near the edge between the pasture and this enthusiastic, weedy floodplain jungle. Now about 60 of them take off and stream east in a scraggly line, passing in front of Mount Helena.

From swallows to cranes

We spot a couple of cliff swallows dipping low over the ponds, catching insects. A female mallard, wings tucked, glides in and lands with a splash. Moments before she lands, she’s already invisible among the rank floodplain growth. And what’s that massive bird flying downstream? We raise our binoculars and see the long, thin neck of a lone sandhill crane. It flaps on past us, its silhouette crossing the distant, smoky Elkhorn Mountains.

A few of the magpies are still perching nearby. It’s an astounding group that we’ve seen this morning, well over a hundred of them. It’s another sign of the season. This year’s magpie chicks have fledged, and several families with young have joined together to form this flock. 

One of these magpies is closer now, and I can see that its tail is short. This is probably one of the fledglings. 

The sun is two hours high now, and a few insects are beginning to sing. I recognize the distant, evocative trill of a four-spotted tree cricket (Oecanthus quadripunctatus). I’m still learning my singing insects: eventually I hope that I’ll be able to do a blog post on them.

The grassy floodplain

As we continue upstream, the floodplain gets grassier. There are still large stands of white sweetclover along the stream, but the dominant vegetation is now grasses, sedges, and Baltic rush (Juncus balticus). We’re approaching our first mature shrubs now: a row of chokecherries (Prunus virginiana) near the new stream channel. When we began watching this site in 2017, these chokecherries were already full-grown. They only burned partially in the fire two years ago, so their canopies are still relatively full. And today, the area around them is bursting with activity.

Along the stream, a yellow warbler is sallying forth over the water, catching insects and landing in the sweetclover clumps. A flock of nearly 40 red-winged blackbirds are perching in the chokecherries, constantly making their kak calls. A Bullock’s oriole lands in a young willow along the stream nearby, then flies to the chokecherries and gleans insects along the branches. 

More vesper sparrows and Savannah sparrows are perching in the chokecherry thicket. In the far end a small flock of house sparrows lands, vocalizing. We don’t see house sparrows here very often – usually they stay close to houses – but sometimes they wander over from the homes that border this site.

We watch a cedar waxwing flycatching along the stream, flapping above the gentle meanders of the channel and then landing in an alder. Another waxwing is doing the same thing farther away, taking advantage of the late summer insects. In the distance, we can hear the musical tinkle of horned larks as little groups fly over.

Striped birds and striped crickets

In the sweetclover, I notice a stripy, buffy and brown bird with a pointed bill. It’s almost the size of a red-winged blackbird, but this is something different: it’s a bobolink. These uncommon birds nest in lush hayfields and pastures, but now their nesting season is over. Today’s bird is solitary, although in the past we’ve seen small flocks stopping over here at this season. Bobolinks have an incredible migration, journeying as far south as Argentina for the winter. This is a special bird to see here.

Now we’re walking past another series of small ponds. These ones are older: this phase of the restoration happened four years ago, in 2018. The surrounding vegetation is still grassy, much more open than the dense tangle downstream. There’s no jungle of plants to wade through here.

Once again, we search for shorebirds, but we aren’t finding any around these ponds, either. This isn’t a total surprise: shorebirds like mudflats, and that’s a habitat we don’t have much of here. There are a few more red-winged blackbirds perching in the flooded willows and alders along the margins. We also spot a juvenile western kingbird, the first of the morning, perching here all by itself.

Bird activity is slowing down as the morning warms up. Still, we can hear another common yellowthroat making a chak call from the cattails. A few striped ground crickets (Allonemobius fasciatus) have begun singing from the moist soil near the pond edges.

Cottonwoods and new beginnings

Now we’re walking past an area where Prickly Pear Land Trust volunteers planted 400 cottonwoods, willows, and other native shrubs along the stream this spring, with funding from a Last Chance Audubon grant. Most of the plantings seem to be doing well so far, in spite of the dry summer. They’ve gotten their roots down to the water table. And recently, Prickly Pear Land Trust intern Olivia Jakabosky coordinated volunteers to install browse cages, protecting the tender plants from deer.

Mourning doves keep flying past us, going upstream in groups of two or four. By now, we’ve counted 37 of them. Most continue farther upstream, but one lands in a dead alder over one of the ponds.

Already, it’s clear that these ponds and the flooded shrubs around them are supporting a variety of birds. But these cottonwood seedlings in particular get me excited for the future. As they grow up into vigorous thickets – and then, eventually, into a canopy layer over the stream – it’s going to be neat to see how the birds respond. Cottonwood forests support so many species, from the yellow warblers that we’ve seen here today to least flycatchers, downy woodpeckers, and even western screech-owls.

Sevenmile Creek: the old channel

We’ve now passed by the intensively restored sections of the stream. We’re into an area where the creek is still in its old, down-cut channel. But in 2018, contractors excavated some inset floodplain areas here to provide a place for spring floodwaters to go. One of these is already growing up with a low, solid carpet of willow seedlings. Like the tiny cottonwoods we just passed, these willows are the future of bird habitat here.

There’s a willow flycatcher calling occasionally along the stream, sallying out to catch insects. Farther upstream, we can hear several more eastern kingbirds. Some of the mourning doves we saw in flight earlier are perching here. We listen to a gray catbird, the first of the morning, mewing from the thickets above us. 

The wing whir of mourning doves in flight accompanies us as we continue upstream. The thickets we’re walking past now pre-date the restoration work. Chokecherries, alders, and sandbar willows (Salix exigua) are the common shrubs along this narrow stream corridor. But although the habitat here is more mature than downstream, the future potential of the riparian vegetation in this section is much less. A decade from now, the shrubs of the restored sections may be ten times as extensive as these thickets.

Rapid regrowth

Nevertheless, this area tells us a story of resilience. Almost all of these chokecherries and alders were completely top-killed two years ago when the fire swept through. But the chokecherries have sprouted back from their underground rhizomes. Already, the new shoots are almost head-high in places. They’ve regained probably half of the biomass that they had before the fire. And it’s a similar story with the alders, which have sent new leaves forth from their trunks.

We walk past a shallow wetland area, filled with cattails, sweetclover, and rushes. Like all of the wetlands on this site, this one was created as part of the stream restoration work. Here, the birding gets busy again. Fifteen gray partridges leap into flight, displaying their rusty outer tail feathers as they whir off into the distance. And these aren’t the first partridges we’ve seen this morning – this flock brings our partridge count up to 45. Clearly, some partridge nests were successful here this year.

Goldfinches and lazuli buntings

Another mourning dove is sitting tight in a thinleaf alder along the stream, near a couple more eastern kingbirds. A goldfinch is perching in the top of another alder, making its cheerful potato-chip call. In the chokecherries on the other side of the wetland, we spot a male lazuli bunting. These buntings migrate early: today may be our last chance to see them here this year.

In the face of our increasingly hot and dry summers, it’s encouraging to see the resilience of these chokecherries and alders. Even as our weather gets more intense and chaotic, they’re still able to grow back after a fire burns them to the ground. Nevertheless, the fire has been a setback. None of the chokecherries are bearing fruit this year. We’ll have to wait at least another season before they flower in abundance and produce the bounty of fall fruits that have brought so many cedar waxwings and robins here in previous falls.

The color of a fledgling’s mouth

Our footsteps crunch loudly through the dry grasses. We’re at the tail end of the breeding season. Virtually nothing is singing. The vesper sparrows, mourning doves, gray partridges, and magpies are all flocking. Today we’ve been seeing a mix of local breeding birds and early migrants like the Cooper’s hawk. A month from now, most of these breeding birds will be gone, and hundreds of migrant songbirds will be stopping here.

I notice an eastern kingbird that still has a little bit of yellow around its mouth. This colorful skin tells us it’s a fledgling. When this baby bird opens its mouth to beg, its parents see a colorful yellow target. Feed me! Feed me! It’s a message conveyed by a bright yellow gape as well as by the young bird’s begging calls.

A band of convective clouds is moving over the continental divide, creeping slowly towards us. A few outlying cloud wisps cross over the sun, giving us a little bit of shade. The morning is getting hot now. We’re still seeing lots of mourning doves flushing ahead of us along the creek. And the vesper sparrows are everywhere.

Another sparrow in the thickets

Then we spot a chipping sparrow perching in a chokecherry. It has a longer tail and slimmer body than the vesper sparrows. It’s streaky below, even though adult chipping sparrows aren’t: this is a juvenile. It’s got a dark line running across the middle of the face and continuing ahead of the eye: a good field mark to look for on fall chipping sparrows.

The white clematis (Clematis ligusticifolia) is mostly past flowering down along the creek. Its graceful vines hang with silky white fruits, clambering over the alders and making a dense thicket. Clematis makes good cover for nesting birds. Nearby, there’s a small patch of giant goldenrod (Solidago gigantea) in bloom. We stop for a minute to admire the diversity of wasps, bees, moths, and flies visiting these flowers. 

Now we’re walking through an area where the alders burned hot in the fire. Like the alders downstream, they’re resprouting, but much more slowly and from near the base. It’s going to take these ones a while to recover. In the meanwhile, though, the goldenrod and cutleaf coneflower (Rudbeckia laciniata) are offering nectar for pollinators underneath them. And the chokecherries, farther away from the stream, are growing back faster, already forming a nice, clumpy thicket.

Of clouds and winged specks

The clouds are still hovering over the continental divide, ominous and blue. A strange formation is developing: a lumpy cloud raft, streaking out towards us from the larger cloud bank. The raft is made up of mamma clouds. The unusual sight lasts for several minutes, then gradually dissipates. A thin layer of clouds are still covering the sun, giving us some relief from the heat.

Then I notice a little speck circling against the gray. We raise our binoculars and see that it’s got very pointy wings. It’s so far away that it’s hard to see much more. Nevertheless, we can tell it’s a substantial-sized bird. It circles on a thermal, a tiny dot that almost disappears from sight as it rises higher. With those long, pointy wings, it’s definitely a falcon. I pull out my camera and play the game of hunting for this fast-flying speck among all of the clouds, trying to get photos. I manage to snap a couple as it gets higher and higher.

The photos are nothing incredible. But they’re enough to show us a well-defined, black hood on the side of the face: it’s a peregrine falcon.

There’s something awe-inspiring about these birds. Never a common sighting, they’re bird-hunting athletes, maneuvering across Helena’s skies as if a flight from horizon to horizon is nothing more than a walk to the mailbox. Any time I see a peregrine, I feel small, ground-bound, and awkward. A day with a peregrine falcon in it is a special one.

Another new sparrow

A small sparrow flits from a chokecherry to another perch ahead of us. At first I pass this one off as another vesper sparrow, but Stephen stops me: he didn’t see the characteristic white outer tail feathers when it flew. We take a closer look. We notice that this bird has a very large bill, a short neck, and a delicate row of streaks across the middle of the chest.

It’s a juvenile grasshopper sparrow. We can still see a little bit of pale yellow around the edges of its gape, where it begged for food. This is a good sighting for the Helena valley. These grassland-nesters are fairly common in eastern Montana, but around Helena they’re unusual. In fact, most of the grasshopper sparrow sightings in the valley have been here, at Sevenmile Creek.

A great blue heron flaps up from the shrubs beyond us, circles briefly, and then dives back down towards the stream. Three meadowlarks are perching about 40 yards past us now, in the top of one of the burned-over chokecherries. 

Retracing our steps

As we retrace our route back down the stream, a couple of turkey vultures are soaring overhead in an increasingly cloudy sky. The eastern kingbirds are still making their electrical-sparks calls from the regrowing shrubs. A yellow warbler sings occasionally from a thicket. 

The willow flycatcher is still where we left it, near the young willow growth in the inset floodplain area. Farther downstream, more mourning doves are perching in the alders.

The red-winged blackbird flock is calling from the floodplain as we pass back by the last big chokecherry thicket and reach the jungle of rank grasses and kochia that marks the most recent restoration work. A vesper sparrow is perching in the chokecherries with an insect in its beak. Evidently this one is still feeding fledglings.

From floodplain to grassland

We wade back through the lush growth of the floodplain. A violet-green swallow is darting nimbly overhead, catching insects in midair. It’s past noon now, and in spite of the cloud cover it’s gotten hot. The song of katydids fills the air, a lazy buzz and tick that seems to swell and contract around us.

We’re walking back across the grassland now. I’m taking a few notes when Stephen spots another raptor flying quickly north over us. It’s large, with pointed falcon wings like the peregrine that we saw earlier. But as we follow it with our binoculars, we can see that this one has dark wingpits and is brownish above. It’s a prairie falcon, another magnificent, cliff-nesting predator. And like the peregrines, prairie falcons incredible in the air, roaming widely as they hunt rodents and birds.

The birds and their stories

Even on this one day, we’ve seen so much here. Hundreds of birds, dozens and dozens of species. They tell a story of late summer fading into fall. Birdsong is quiet. Fledglings are on the wing. The birds are flocking up, finding grasshoppers and preparing for migration. Already, several of our local Sevenmile Creek breeders are gone for the year: Brewer’s blackbirds, spotted sandpipers, killdeer, and brown-headed cowbirds. Others are new arrivals from elsewhere, either migrants or drifters. Among these are the Cooper’s hawk, the chipping sparrows, and the grasshopper sparrow.

There’s so much that we can wonder and will never know about these birds. Where have they come from? Where are they going? What are their lives like? Some of it we can learn. But much of it will always be a mystery – stories that we can glimpse, perhaps, but never really know. 

What we do know is this: these birds bring this stream restoration project alive. To me, Sevenmile Creek is an inspiration. It’s an example of what we, as a community, can do when we work together to improve habitat.

Sevenmile Creek: a roadmap for restoration

Even though this project is young, it’s already easy to see that it’s been successful. Even now, the habitat here is supporting dozens of gray partridges, mourning doves, and vesper sparrows. There are meadowlarks and swallows. Sandhill cranes fly past while great blue herons land to forage. This is a place where eastern kingbirds flutter after insects and dive-bomb Cooper’s hawks.

But much more than that, this place is a roadmap for what is possible when we all work together to restore the landscape where we live. Already, these new ponds and wetlands are holding water and supporting wildlife through our increasingly hot summers. When spring runoff is high, there’s a safe place for floodwaters to go without damaging houses and farms. And in a few more years, there will be new cottonwoods and chokecherries shading this stream, keeping the water cool and supporting an even greater diversity of birds.

Some days, it seems like there’s a lot of bad news in the world. And on those days, it’s a joy to be able to go outside with a friend and watch our local birds as they transition from the nesting season to the first hints of migration. Through Sevenmile Creek’s birds, we have a window in on a continent of birds getting ready to move. And we have a clear picture of how restoring a stream can help more life thrive around us. It’s a gift to have this here.

The post Sevenmile Creek: restoring a stream and tracking its birds appeared first on Wild With Nature.

July 31, 2022

I’m standing along Helena, Montana’s Centennial Trail on this hot summer evening, contemplating a mystery. The mystery is a plant: Mentzelia decapetala, ten-petal blazingstar. Tightly closed, luminous white flowers rise above the toothy, sandpaper-textured leaves. Mentzelia plants, with their massive blooms and unique foliage, would be striking in any garden. But here they seem to be thriving without anyone’s care, a group of native plants in the middle of the city, growing along an abandoned railroad track. Like bold, living sculptures, they pose questions without offering obvious answers. I can’t help but wonder: what lies beneath their showy appearance? What’s the story of these plants’ lives?

When I do a quick Google Scholar search, I’m surprised to find that very little has been written about the ecology of Mentzelia decapetala. These plants are truly a mystery: I can think of so many questions. The leaves are so rough that they stick to my fingers and pant legs. Why such sticky foliage? The flowers are massive and showy, but right now they’re tightly closed. When do they open? Which insects pollinate them? Around Helena, these plants are closely associated with barren habitats: rockslides, sparsely vegetated slopes, abandoned railroad tracks. It seems incredible that they even survive – let alone thrive – in such harsh places.

Before I make any more field observations, I decide to do a more thorough search of the literature. And here and there, mostly in articles about related Mentzelia species, I find some tantalizing hints. These bits and pieces all seem to be pointing to what I had originally suspected: the story of this plant is a remarkable one. 

Mentzelia pumila, the death trap plant

Through my reading I learn that a close cousin, Mentzelia pumila, is also covered with clinging hairs. If we zoom in with a microscope, we can see that these hairs form a thorny forest of hooks and barbs, lying in wait to snag passing insects. It’s a death trap where these insects perish slowly, their wings or legs caught on tenacious hooks. According to scientists Thomas Eisner, Maria Eisner, and E. Richard Hoebeke, during their study the Mentzelia pumila plants “seemed invariably to have numbers of dead insects stuck to them.” It appears that these miniature, deadly forests of hairs can catch almost any type of insect that visits this plant. They did find one exception, though: the aphid Macrosiphum mentzeliae picks its way slowly through the hairs, avoiding the deadly barbs. Hidden among a dangerous, microscopic forest, this aphid manages to make a living feeding on Mentzelia pumila.

Why is Mentzelia pumila covered in these gnarly traps? It seems to be a defense against herbivores. But in their article, Eisner, Eisner, and Hoebeke suggest that this plant might also be passively hunting insects, benefiting from the additional nitrogen that their corpses might contribute to the soil nearby.

Fly killers, bee lovers

Could the clinging hairs of Mentzelia decapetala act similarly? Eventually, I unearth a hint that they may. It’s a brief mention in an 1879 journal, hiding under the antiquated name of Mentzelia ornata. (This name was historically used for M. decapetala.) Watching this American plant in a French garden, where it had been planted, an observer found flies visiting the foliage, apparently attracted to a fluid secreted by soft, glandular hairs among the stiff barbs. The flies would frequently find themselves caught by the barbs. They would either die there, trapped, or pull their heads off in their frantic efforts to escape. Flies, don’t land here! This plant is a death trap!

I also find an article about another related species, Mentzelia nuda. This one discusses pollination and suggests that, unlike the leaves, Mentzelia flowers can have a more positive relationship with insects. This study documents a variety of bees and several small flies visiting Mentzelia nuda blooms. Among these bees are two Mentzelia specialists, Perdita wootonae and Andrena mentzeliae. There are also various generalist bees, including the golden northern bumblebee (Bombus fervidus). Mentzelia nuda flowers produce nectar deep inside, among the dense stamens. And in this species, nectar production actually lasts for about 10 days after the petals fall, attracting ants to the developing fruits. The ants seem to defend the seeds against the beetles and moths that attack them, increasing seed production.

More from the literature: from flowering to dispersal

Mentzelia nuda flowers open in the late afternoon and close near sunset. Not so for our Mentzelia decapetala, according to the only study I can find that discusses pollination in this species. This study, from Nebraska, tells of flowers that open about an hour before sunset and close again near midnight.

In the Nebraska observations, honeybees and sphinx moths were the most common insects that visited Mentzelia decapetala flowers. The researchers also found bumblebees, grasshoppers, and a few other moths on the flowers.

This patchwork of information gives us a tantalizing sketch about the life of Mentzelia decapetala. It’s a plant of contradictions, finding a way to make a living in barren, dry habitats. A flower of the dusk and the night, it feeds bees and sphinx moths. The leaves, on the other hand, are a miniature forest of wicked, barbed spines: a graveyard for unwary insects. Another paper reports that the seeds are winged, scattered to new homes by the wind.

It’s a fascinating sketch of a plant, but it’s far from complete. And is this sketch even accurate for our local Mentzelia decapetala patches around Helena? It’s time to head out into the field and find out.

Into the field: afternoon at Devil’s Elbow

August 2, 2022

It’s a hot, windy mid-afternoon. I’m standing on a steep, shaley, southeast-facing slope near Devil’s Elbow Campground, baking in the summer heat. There are hundreds of Mentzelia decapetala plants here, growing up out of the hot shale. All of the flowers are tightly closed right now. So far, this matches with the Nebraska study: this plant definitely isn’t an afternoon bloomer.

I start searching the foliage, looking for insects. Will I find any of them trapped here, like the large numbers that have been found on Mentzelia pumila? At first glance, I’m not finding trapped insects. Instead, I find spots of a dark, viscous, sticky substance on the leaves. It looks like molasses. I taste a little bit. Surprisingly, it’s slightly sweet like molasses, too, though there’s a bitter aftertaste.

I’m amazed to find a Mentzelia plant that’s been browsed, the tips of its stems bitten off. This is a total surprise – what would eat these hairy, sandpapery plants? Could it be deer? As a gardener, I know that deer have an incredible ability to eat seemingly unpalatable vegetation. But I can’t imagine that even a deer would enjoy such an unpleasant-textured plant.

I find a stem with marks of an injury, and there’s this same blackish liquid congealed near the wound. This seems to confirm what I’ve already been starting to suspect: this black substance is Mentzelia sap.

Not far away, I find a few more stems that have been bitten off near their tops. Surprisingly, though, even though I’ve checked about a dozen plants, what I’m still not finding is any sign of trapped insects. I haven’t yet seen a single invertebrate stuck among the hairs, unlike what the literature records for this plant’s close relative, Mentzelia pumila.

Deadly hairs

And then, as soon as I think that, I find my first insect victim. It’s a tiny fly, about 2 millimeters long, black with red eyes. It’s slightly shriveled and very dead. Its legs are stuck among the forest of hairs, on a bract below a flower bud.

Now my search for tiny creatures becomes more productive. A medium-sized spider skitters from among the flower buds, untrapped and very much alive. Clearly some invertebrates are able to get around in spite of the hairs. And at least on this species of Mentzelia, it’s not just aphids.

Next I spot a small, soft-bodied fly. This one is another casualty, stuck to a drop of sap below a flower.

Unfazed weevils and a struggling moth

Now I notice a small, blackish weevil. Like the spider, it’s not trapped at all, crawling nimbly along the stems and across the flower buds. In my literature search, I found an article by Kathleen Keeler reporting the weevil Orthoris crotchi as a seed predator on Mentzelia nuda. Perhaps the weevil I’m seeing is Orthoris crotchi or something similar: a seed predator on Mentzelia decapetala.

As I part the leaves to check for insects, they catch on my fingers. It’s an interesting sensation for me, though clearly a deadly one for some insects. Others navigate the hairy forest unimpeded. I spot a second weevil on a flower bud, crawling quickly across.

Next I find a narrow-winged moth, perching on another flower bud. It’s still alive, but it struggles as I get photos: a leg is stuck among the barbed hairs. Why is it that the Mentzelia foliage is a death trap for some creatures and not for others?

I walk past several more plants whose tops have been browsed. I wonder if a mule deer in the neighborhood has a stomachache right now.

More creatures among the foliage

I keep checking more Mentzelia plants, especially focusing on the clusters of flowers and buds where I seem to be finding the most invertebrates. But the search has slowed down again. I’ve found a few more weevils, none of them stuck. Insect prey trapped here at this season seems sparse.

I spot a tiny spider, gray with black speckles on its abdomen, hiding among the flowers. It jumps onto my finger and then I release it back where I found it.

It’s still early in the bloom period here. Many plants only have green flower buds. Various others are within their flowering window, the bulky white petals wrapped tightly together in the afternoon heat. Only a few plants have immature fruits yet, their white petals fallen to the ground and the green capsules swelling with seeds.

Attracting ants?

I check the tops of these few developing fruit capsules. If this was Mentzelia nuda, I would expect (based on the literature) to find the tops of these fruits still producing nectar, attracting ants to protect them. The literature told me nothing about whether Mentzelia decapetala might attract ants in the same way, so it’s up to me to check.

So far, it seems that the answer is no. I’m not seeing any ants visiting these fruits, and the tops of the capsules appear dry rather than sticky. Unless I’m missing something, it seems that Mentzelia decapetala stops producing nectar when it stops flowering.

On the hairy margin of a developing Mentzelia fruit, I spot another medium-sized black fly. It’s upside down, shriveled, and dead. So far, flies seem to be the primary victims of this plant’s clinging hairs.

Then I spot another trapped moth, this one tan with black speckles, its wingspan as wide as my thumb. It’s stuck to the flower bracts. 

The sun will shine on this slope for hours longer today, but already the shale is blistering hot. It almost burns my bare leg as I kneel on it. 

Lessons in the heat of the day

I haven’t found a single open flower here this afternoon. The smooth, waxy white petals are clenched tightly, just like researchers reported in Nebraska.

This Mentzelia population is a mix of sizes and shapes. There are the tall, branching plants I’ve been checking for insects. Between them, low to the ground, there are smaller plants. So far, these ones are just rosettes of deeply toothed leaves. And scattered among these two forms, there are also the dead, bleached skeletons of plants from previous years.

This mixture of rosettes, flowering plants, and dead skeletons says “biennial” to me. And indeed, the Manual of Montana Vascular Plants reports this life cycle for our populations of Mentzelia decapetala. Biennial plants typically live for two years. In the first year, they start out as a low cluster of leaves. In the second year, they grow taller and flower – and then they die. But they live on through their seeds, which give rise to the next cohort of young plants.

It’s sweltering out here, and I’m ready for a break. But before I go, I find another flower with a small, midge-like fly trapped on it. I collect this one and bring it back so that I can take a closer look in the lab.

What have we learned out here? It seems that, at least at this season, trapped insects aren’t very common on these plants. Would this picture change later in the year? Or is Mentzelia decapetala just less of a fly-catcher than Mentzelia pumila? It’s impossible to tell without watching these plants over a longer time. But it’s clear that these hairs are an effective trap for some insects – especially soft-bodied moths and flies. 

From dawn to dusk: Mentzelia along the tracks

August 3, 2022

It’s almost an hour before sunrise, and I’m back among the Mentzelia decapetala plants along the Centennial Trail. At this hour, the flowers are all tightly closed. They glow softly in the blue-white glare of the streetlights.

Closed flowers in the afternoon, closed flowers before dawn. It matches with the Nebraska observations, the only published information I found on the flowering of Mentzelia decapetala. So far, it seems that Helena’s Mentzelia behave like Nebraska’s Mentzelia, opening shortly before sunset and closing sometime during the night.

Hairs under the microscope

Later in the day, I stop at Carroll College. I want to use a high-powered dissecting microscope to take a closer look at the Mentzelia leaf and flower that I collected the day before. Under the microscope, I can see that the plant’s protective hairs have tiny barbs along their entire length. The hairs seem to be longest and most prominent on the bracts that surround the flowers. This is also the region of the plant where I’ve found the most trapped moths and flies so far. Are the hairs a system of protection for the flowers, in particular? Each hair looks like a miniature, extremely narrow-crowned fir tree – or perhaps a weapon from a nightmare. As we’ve seen, for certain flies and moths, perhaps “nightmare weapon” is indeed the best description.

Strangely enough, the small fly that was trapped here yesterday has disappeared! Only a few leg fragments remain to tell me that I didn’t imagine the whole thing. Where has it gone? Frankly, I have no idea. My best guess is that another invertebrate – perhaps a spider – had been spending the day inside the Mentzelia flower. Stored in a plastic vial overnight, I imagine that this hypothetical predator emerged from the flower and ate the trapped fly.

Mentzelia in the evening

It’s 8:00 pm when I return to the Mentzelia patch along the Centennial Trail. The sun is sinking, but the evening is still hot: it’s 90°F right now, and the heat is made just slightly more bearable by a gentle westerly breeze. The Mentzelia flowers are beginning to open: striking, starlike white arrays with bouquets of glowing yellow stamens inside. I sniff one of them. It does have a fragrance, but the smell is delicate, just a little whiff of perfume.

Already, I’m noticing bees on these flowers. But unlike the Nebraska Mentzelia decapetala, which honeybees visited in the evening, the common visitors to Helena’s Mentzelia patch are all bumblebees.

A plethora of bumblebees

I’m carrying my insect net tonight. In short succession, I catch three bumblebees as they go from bloom to bloom. They seem to be focusing their efforts near the tips of the stamens, clambering about on them and apparently collecting pollen. 

I walk over to another large, bushy plant, growing right along the abandoned railroad spur line. This one is barely open yet, just the first few flowers beginning to unfurl. Here I spot another bumblebee. She hovers briefly near the closed flowers, just long enough to decide they aren’t worth bothering with right now, and then lands among the stamen bouquet of a barely-open bloom. 

I didn’t expect that I would be doing a repeat of last week’s bumblebee observations tonight! But I did bring a cooler of ice with me, so once again I’m netting every bee I can catch and cooling them down to identify them. 

Another bumblebee arrives at this Mentzelia plant and I net her as well. So far, every single bee I’ve seen tonight has a bold orange band across her abdomen. I’ll need to take a closer look and double-check, but it seems that these are all Hunt’s bumblebees (Bombus huntii) – the least picky flower visitors of the seven bumblebee species we found near Helena last week.

Life and death in the Mentzelia patch

It’s 8:20 now. I continue moving from plant to plant. Most of the flowers are still closed. And of the blooms that have opened, most have still only unfolded halfway. They’re white cups right now, not the white platters they’ll soon become. 

But they’re open enough for the bumblebees. I’ve caught seven individuals now, all with rusty-banded abdomens. And so far, bumblebees are the only flower visitors I’ve seen. I’ve noticed a few small, blackish weevils crawling on the outer surfaces of the flower buds – presumably the same weevil species I found during yesterday’s midafternoon visit to Devil’s Elbow. Now I spot a pair of these weevils mating on a Mentzelia leaf. Just like yesterday, they seem completely unfazed by the barbed hairs that cover the leaves.

Tonight I’m mostly focused on flower visitors, though I’m also trying to notice any insects trapped on the foliage. I’m not seeing many dead bugs: like the pattern I noticed at Devil’s Elbow, the trapped creatures seem few and far between. Nevertheless, I do notice a bee fly (family Bombyliidae) stuck to a flower bud, its wings extremely frayed. It’s been dead here for a while. 

It’s interesting to reflect on the dual nature of this plant. Its leaves can be deadly – but the weevils and the spiders seem to navigate them without trouble. Its flowers, on the other hand, seem relatively safe. I haven’t found a single trapped bumblebee anywhere. Unlike showy milkweed, whose flowers sometimes trap and kill honeybees, Mentzelia flowers seem to be trap-free for pollinators.

Approaching sunset

Like the plants at Devil’s Elbow, the Mentzelia here have just a few fruiting capsules developing so far. And again, the disks on top of these capsules are dry, without any sign that nectar is still available after the flowers have withered. There are no ants on these fruits – although I do notice a reddish ant trying to crawl into a tightly closed flower. The pattern I saw at Devil’s Elbow is getting reinforced: unlike Mentzelia nuda, it seems that Mentzelia decapetala does not attract ants to protect its maturing seeds.

It’s 8:30 now. The wind has died down and the sun is just a finger’s width above the western mountains. The evening light is becoming a rich golden. I walk over to a patch of plants on a rubble slope near the old railroad tracks. Here, the flowers are mostly open now. The bumblebees are staying very active. There are at least three just in this patch, each one diligently rummaging among the deep yellow anthers.

Bumblebee ID

Now I return to my cooler and check on the bumblebees. Am I right that they’re all Hunt’s bumblebees, or is there a surprise here? The bees I caught earliest are mostly chilled now, just twitching slightly. I run through the identification process with them. They all have moderately long cheeks, yellow hairs on the face, and bold yellow stripes across the thorax. I’ve done my due diligence now – and as I had suspected, these are Hunt’s bumblebees (Bombus huntii).

They all look similar, so I run through the identification process quickly, even managing to confirm the identity of those that have not yet cooled off fully. They’re all females, and all Hunt’s bumblebees. Most of them have very full pollen baskets, heaped high with a tawny yellow mixture of nectar and pollen. Now that I’ve confirmed their identities, I can let them all go. Freed from their vials, they shiver to raise their body temperature. Then one by one, they fly off into the fading light.

Hoverflies at sunset

Now it’s 8:40. The sun has just set behind the mountains. The Mentzelia flowers are fully open now. I notice a small hoverfly (family Syrphidae) perching on a Mentzelia stamen. It flies off as I approach. Several Hunt’s bumblebees are still active, their gentle buzzing barely audible against the background noise of traffic from Benton Avenue nearby.

I spot a larger hoverfly, also visiting the tip of a Mentzelia stamen. His abdomen is black with narrow, curved white markings. Like most hoverflies, this one is wary. He levitates above the flower before I can get a photo of him. He hovers a few feet away, controlling his position as carefully as a helicopter. I inch my insect net into position and swipe. I’m expecting he’ll dart away, evading the net – but surprisingly, I manage to catch him. I suspect he’s a white-bowed smoothwing (Scaeva affinis), a relatively large and distinctive hoverfly I’ve observed before around Helena. (And later, with a closer look, I’m able to confirm that I’m correct.) I only see this single individual, but it’s still a record of another species that is showing an interest in Mentzelia flowers. The white-bowed smoothwing is known to visit a variety of flowers; the larvae hunt aphids.

Mentzelia moths?

As the twilight fades, I’m starting to think about moths. So far, the Nebraska observations of Mentzelia decapetala seem to be a fairly good match for the patterns I’m seeing. There, the common flower visitors on these evening flowers were honeybees and sphinx moths. Here I’ve found Hunt’s bumblebees instead – a native species that, like honeybees, visits a wide range of flowers. Will I find sphinx moths, too?

By now, nearly all of the Mentzelia flowers have opened. I’m kneeling along the abandoned rail line, at the edge of an extensive patch of these white starbursts. Three Hunt’s bumblebees are still going from flower to flower here. It’s quite a way to spend an evening. I’m watching a Helena summer spectacle: one whose beauty I couldn’t really imagine until this week. Mentzelia decapetala pollination at sunset: it’s a striking contrast. I’m kneeling in a wasteland, a few feet from a car seat that someone has discarded, yet I’m in the midst of this patch of smooth white petals, exuberant yellow stamens, and sandpaper green leaves growing where no one cares about it. Still no moths, though.

Will any show up? I really have no idea. I alternate between kneeling at the edge of the patch and pacing among the plants. I’ll give the moths a bit more time.

By 9:10, the last of the bumblebees have finished their foraging for the evening. The blazingstar patch stands quiet, the luminous yellow and white flowers catching the fading light like beacons. Their scent seems stronger now, though it’s still just a delicate perfume.

I’m still waiting and wondering. Is this all for the night? Or is it just the beginning of the show?

White lines in the twilight

It’s 9:20 when I spot my first sphinx moth. It’s massive, larger than a hummingbird, far bigger than I had imagined. Its abdomen is as thick as my index finger, spotted with white. Its wings flash white and rosy as it moves soundlessly from flower to flower. I edge closer and sweep my net. Incredibly, I manage to catch it. The moth flutters in the net bag and I start walking towards my car to retrieve a butterfly observation cage. As I walk, I spot a second sphinx moth, similarly patterned, silently probing the glowing white flowers.

Watching the moth flutter in the butterfly cage I’ve retrieved, I immediately realize that its massive size isn’t the only striking thing about it. Its forewings are intricately patterned. There’s a broad, tan stripe running through the middle, intersected by narrower white veins. Occasionally I can catch a glimpse of the incredible, salmon-colored hind wing. It’s a white-lined sphinx (Hyles lineata). Looking it up, I read that the larvae of this widespread moth can feed on a variety of plants, including willowherb (Epilobium) and evening-primrose (Oenothera). And although it’s a common species, this is the first time I’ve seen one around Helena. No wonder. The adults are mostly active at twilight and after dark – times when I haven’t been out searching for them.

White flowers in the night

It’s 9:40 now. The last hint of the sun is a peachy glow to the northwest. I can see a number of tiny micro moths flying around the Mentzelia, but I can’t tell if they’re actually visiting the flowers. Another white-lined sphinx is flying around, quietly dipping its proboscis into the showy white blooms. In spite of its bulky body, it’s a fast, agile flier.

I’ve forgotten to bring a headlamp with me tonight. The flowers are still glowing, though, illuminated by the floodlights from the Batch athletic fields in the distance. But without a headlamp to help me, it’s getting difficult to see what’s visiting the flowers now. Are there other insects flitting from bloom to bloom in the night? Perhaps other moths, or nocturnal bees? It’s a question that will have to wait for another time.

But just as I turn to go, I spot another moth alighting among the stamens of a Mentzelia flower. This one is medium-sized: still substantial but maybe a quarter of the size of the white-lined sphinx. Before I can catch it for a closer look, it flutters off into the night.

There’s something I find captivating about this plant. For some insects, it’s a prickly killer, trapping small flies and moths with its miniature barbs. For others, like the weevils, it seems to be a home. And on these warm summer nights, it’s a spectacle that few people get to see: showy white flowers that open near sunset, attracting orange bumblebees and enormous sphinx moths. Among the discarded trash along this abandoned rail line, it’s nice to know that this kind of magic still exists.

Further reading

Brown, D.K. & Kaul, R.B. (1981). Floral structure and mechanism in Loasaceae. American Journal of Botany 68(3):361-372. Retrieved from http://www.jstor.com/stable/2442772

Eisner, T., Eisner, M., & Hoebeke, E.R. (1998). When defense backfires: detrimental effect of a plant’s protective trichomes on an insect beneficial to the plant. Proceedings of the National Academy of Sciences 95(8):4410-4414. Retrieved from https://www.pnas.org/doi/abs/10.1073/pnas.95.8.4410

Gray, A. (1879). The beheading of flies by Mentzelia ornata. Botanical Gazette 4(10):213-214. Retrieved from https://www.journals.uchicago.edu/doi/pdf/10.1086/325279

Keeler, K.H. (1981). Function of Mentzelia nuda (Loasaceae) postfloral nectaries in seed defense. American Journal of Botany 68(2):295-299. Retrieved from https://www.jstor.org/stable/2442861

Keeler, K.H. (1987). Survivorship and fecundity of the polycarpic perennial Mentzelia nuda (Loasaceae) in Nebraska Sandhills prairie. American Journal of Botany 74(6):785-791. Retrieved from https://www.jstor.org/stable/2443859

Lesica, P., Lavin, M. & Stickney, P.F. (2012). Manual of Montana vascular plants. Fort Worth, TX: BRIT Press. 

Schenk, J.J. (2013). Evolution of limited seed dispersal ability on gypsum islands. American Journal of Botany 100(9):1811-1822. Retrieved from https://bsapubs.onlinelibrary.wiley.com/doi/pdfdirect/10.3732/ajb.1300075

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