Four wintery walks

sun and shadow and snowy tracks

The thermometer at my house read eleven degrees (F) after a clear, starry night; the sky looked clear, although the sun wasn’t really up yet. Juneau had recently enjoyed about six feet of lovely snow, but many of the trails had not yet been used much. In search of a well-packed trail, a friend and I headed for the Boy Scout beach trail.

All went smoothly until we reached the junction where the trail splits three ways, and none of the splits looked good. We chose to go right out onto the goose meadow and immediately found ourselves breaking trail and post-holing through deep, crusty wind-blown drifts. Even following in the footprints of my companion, I (weighing forty pounds more) plunged and lunged, knee-deep and more. However, a hundred yards or so farther on, walking became a pleasure again, because the low vegetation was almost clear of snow, thanks to some recent super-high tides that left a few scattered cakes of frozen foam and to the wind.

Post-holing again out to the beach by the iconic cottonwood tree, we decided not to face the stiff, cold north wind that was churning up waters out in Lynn Canal. So, instead of coming back on the big, exposed beach, we turned toward the camp buildings, found a log, and had a little picnic in the sun. As soon as we got out our thermoses and lunch bags, two importunate ravens landed on the beach right in front of us—they knew the drill! Of course, we obliged them, tossing out bits of sandwich that they promptly snapped up. But they eyed a fragment of a sugar-snap pea with great suspicion and avoided going close to it—no veggies for them! One of them chose to sit next to us on the log for a while.

On this day in mid-December, the morning sun barely cleared the horizon. On the upper beach, I noticed that every isolated pebble cast a shadow much longer than itself, making a grid of conspicuous black stripes that called attention to each pebble.

The Chilkats across the canal were spectacular: the low morning sun made sharp contrasts between the sun-bright south-facing slopes and the intensely blue-shadowed north slopes. Behind us, the trees on the hillsides were individually defined by the snow they carried and on the peaks the snow delineated the minor topographical features very nicely.

Few critters were visible on this walk. A seal cruised by, just offshore, and gulls fossicked about in the tidal wrack. A wren zipped rapidly from trailside to shelter under some roots; they are so tiny, I wonder how they stay warm on frigid winter days. No midges or spiders crept on the snow surface.  But there were tracks of mink along the river, red squirrels in the woods, ermine and vole at the edge of the meadow; one or two small birds (who?) had hopped and run in the beach rye lining the meadow trail. A low-flying raven (?) left the mark of one wing-tip in the loose surface snow.

The next day was mostly sunny and, again, very cold (seven degrees at my house in the morning). I opted for snowdrift-free walk on the dike trail. A few tracks of squirrels and maybe an ermine were the only natural history notes of the morning until I had almost finished the walk. And there in the stand of willows was a female pine grosbeak, busily nibbling buds. I frequently see these grosbeak in fall and winter, as they forage on high-bush cranberry, carefully extracting the seed and dropping the red fruit pulp—the opposite treatment from that of bohemian waxwings, who eat the fruit and excrete the seed.

A couple of days later, the cold remained (just six degrees here). I had an idea to try some of the lower meadows along the Eaglecrest Road, but roadside parking was hard to find and the thought of plowing through deep snow, even on snowshoes, was daunting. So, on up the road to the Lower Loop, nicely groomed and unoccupied. The sun couldn’t make it up over the peaks, but ‘shoeing was easy.

There was not a live critter in sight but there were plenty of signs of life. A porcupine was into long-distance travel, heading straight across the meadow, not stopping to forage. Ermine had cruised all over the meadows in circuitous routes, looking for a juicy morsel. Snowshoe hare tracks were abundant, mostly under sheltering conifer branches or going from one shelter to another. Grouse or ptarmigan had been active, inspecting salmonberry and blueberry bushes for tasty buds and sometimes staying long enough to trample the snow flat. Except for a few squirrel marks, the smaller folk had left no signs on the surfacebut were no doubt active below.

A day or two later, it was still very cold. A group of friends strolled the dike trail, enjoying the bright sunshine as the sun crept over the peaks. A dusting of fluffy snow lay atop a snow crust. Several voles (I think) had made sorties out into the grassy areas, circling back to the trees or to holes under grassy tussocks; we noted at least seven of these trackways, well separated from each other. Looking through the chain-link fence and across a ditch, we saw tracks on a big snow drift that looked like Two-toes—but how could a deer walk up that crusty snow on those thin legs, without punching through, when humans (on our side of the fence) generally ended up post-holing?

Here and there in August

meadows high and low, a snacking porcupine, and odd bear scat

Early in the month, a female mallard arrived on my pond with her late brood of three good-sized young ones, still wearing lots of down. A week later, they were well-feathered except for a distinguishing fuzzy patch of down on the rumps of the ‘kids’. At the end of the month, the kids were no longer fuzzy at all, but they still hung out with mom.

A trip with friends up to Cropley Lake in mid-August was a muddy one. But the meadows were studded with the flowers of swamp gentian and asters. Fish were rising in the lake; Dolly Varden are recorded to be resident in the lake, although a few might wash out downstream at high water. On the far side of the lake, we looked for the sky-blue broad-petaled gentian and found them on a gentle slope. The relatively rare yellow fireweed crowded a small drainage gully, a habitat it seems to like.

Broad-petaled gentian. Photo by David Bergeson

The next day, I cruised around Amalga Meadows near the Eagle Valley Center. The parking area was crammed with cars, but all the people from those cars were either up on the horse tram trail or at the new cabin. So I had the meadow to myself. The grasses were so tall that walking was not easy, except where a bear(?) had stomped through. Nagoon berries were ripe, hidden down in the tall grass, but bog cranberries were still green. The seeds of cotton grass were dispersing in long streamers from the seed-heads. Sweetgrass was seeding well. In part of the meadow, I had to watch my feet closely, so as not to step on the many tiny toadlets that scuttled to safety as they dispersed from their natal ponds.

Porcupine’s lunch. Photo by David Bergeson

Not long after that, I perched on a hillside on the way to Hilda meadows at Eaglecrest. There I watched a tiny red mite, not even a millimeter long, wander up and down over the petals of a swamp gentian, exploring the depths of the flower. From the perspective of such a wee beastie, even those small flowers have depth! Eventually it settled briefly in the deepest part of the flower, perhaps finding something usable there (?).

A walk up the Salmon Creek road with friends found that the some of the many self-heal plants, seen in bloom on a previous walk, were setting seed. By the side of the road, we found several quite handsome, large beetles with reddish-brown carapaces (I think I used to know a name for them). On the way up, we all simultaneously spotted a porcupine trundling along the side of the road ahead of us, and we stopped to watch it. Moving away from us at first, it turned around and began snacking on some roadside greenery. We tried to slither by, but it scuttled into the brush, just a little way, where it sat watching us and shaking its wet fur. We went on, and it came right back to its green lunch. As we came back down the road later, it was still there and made a repeat performance. That must have been a particularly nice meal, not to be abandoned. Near the water tower, we spotted two deer, looking smooth and sleek; one of them stayed to watch us pass by, ears up like flags.

The next day, I went with a friend to the junction of Eagle and Herbert rivers, a spot that has been fun to visit in other years. This time, however, the sketchy little trail was greatly overgrown—only suitable for those less than three feet high at the shoulder, and sometimes it disappeared entirely. On a spruce tree ahead of us, the trunk looked like it had lots of dark spots the size of a fifty-cent piece (remember those?); close-up, those spots turned out to be places where busy woodpeckers had flaked off bits of the scaly bark. Out at the point, otters had romped in the sand. Two ravens spotted us immediately but were too shy to come in for the (obviously expected) offerings we tossed out onto a sandy ledge. On the way back, we found several bear scats full of blueberry remnants and three strange, yellowish deposits composed of short chunks of plant stem and a few devils club seeds. These had presumably been deposited with a lot of fluid, because they were spread thinly and flat on the ground. I’d sure like to know what plant had been eaten and what occasioned those deposits.

Summer flowers

lesser lights shine just as bright

Most of us have favorites among the very showy flowers, such as the fireweeds, or white bog orchids, or columbine, or wild iris, or we look for uncommon species, such as frog orchids. These may be the stars of the show, but we may neglect some ‘lesser lights’ that are interesting in their own right. I’ve picked out just few of these here, simply because I’ve seen them recently on July walks.

In one of the meadows on the way up to Spaulding Meadow, the density of sundews is remarkable—there’s almost a carpet of round-leaf sundew (Drosera rotundifolia) over the mosses, and long-leaf sundew (a.k.a. great sundew, D. anglica) grows mostly on the muddy edges of pools. Sundews are insectivorous, supplementing what they can draw from their nutrient-poor habitat by digesting insects captured on the leaves (and they may have ways to avoid capturing potential pollinating insects). I noticed that very few of the sundews had produced flower buds at this time. Because flower (and eventually seed) production costs energy and nutrients, I wondered if these sundews were not capturing many insects to help fuel flower production. Was there a seasonal low in insect availability or maybe just not enough bugs to feed so many sundews or possibly (as found in one study) too much competition from spiders that want bugs too?  Or something else….??

Self-heal showing fringed lip and hood. Photo by Mary Willson

Along the road to the Salmon Creek powerhouse, the hiking group found common harebells and lots of a small, purple-flowered perennial plant called self-heal (Prunella vulgaris). It’s native across the northern hemisphere and introduced everywhere else. There are multiple flowers in each inflorescence. The flower has a fringed lower lip and an upper hood over the stamens and pistil, but in some cases the pistil extends out in front. Flowers with the pistil inside the hood tend to have bigger and fewer flowers, less pollen, less nectar, and lower visitation rates—and apparently less male function. Although the flowers may self-fertilize if few pollinators are available, they are primarily bee-pollinated.  I watched a bumblebee unsystematically visit nearly every flower on one inflorescence, poking its head deeply into some of them to get the nectar and passing quickly over others (perhaps the nectar had already been taken). 

Self-heal with bumblebee. Photo by Deana Barajas

Studies of self-heal in Japan have shown that the size of the flower in different ecological settings varies with average tongue length of the bumblebees in those settings: bigger flowers in areas with long-tongues bees. In other words, there are local adaptations of flower size to the abilities of the available bees. Other factors, such as altitude or robustness of the plant, did not account for the observed correlation. The size-match of tongue length and flower size affects both male (pollen removal) and female reproductive success (pollen receipt and seed set).

I’ve noticed a small goldenrod on the East Glacier trail near the cliff that sports purple mountain saxifrage in spring and offers a lookout toward what’s left of the glacier. Called northern goldenrod (Solidago multiradiata), it tends to favor rather dry areas in meadows, on rocky ridges, or gravel bars. The yellow flower heads occur in more or less flattened clusters. This plant is much shorter than the Canada goldenrod, which likes disturbed areas and bears its many flowers in large, tapered inflorescences. The small flowers of goldenrods are visited by butterflies, bees, and many other insects, but which ones are the good pollinators and which are just thieves?

Near that same cliff, I saw several common harebells (a.k.a. bluebells of Scotland; Campanula rotundifolia). Found in open areas, rocky or grassy, this perennial is seen in many places around Juneau. The flowers are purple-to-blue, borne singly on each branch, but some plants have several branches on their wiry stems and may have several flowers.

Photo by Bob Armstrong

Common harebell has a broad geographic range over Europe, where it originated, and North America. It survived the advances of the glaciers, which temporarily isolated populations in different areas. Harebells in many of these populations became polyploid, having two or more complete set of chromosomes, which is likely to affect many floral traits, perhaps in different ways in different populations (as found for other species), but this question has not been investigated for this species (as far as I have found). Despite its species’ name (rotundifolia), the round basal leaves disappear early, often before flowering, and the stem leaves are not round.

Harebells are pollinated mainly by bees. The flower is protandrous, meaning that when the flowers first open, they are male, with pollen ready to disperse. Later, when the receptive stigma is mature, the flowers are mostly female. The flowers are self-compatible (as found in experiments), at least in some populations, but self-pollination results in fewer seeds than cross-pollination; in the wild, protandry prevents most self-pollination. Bees collect only pollen from male-phase flowers, but they collect both pollen and nectar from female-phase flowers. Flower size can vary from place to place, and so would the size of the main pollinating insects.

Common harebells (and probably other harebells too) form mycorrhizal associations with several species of fungi. One study found that this association had no effect on seed size or number but led (unexpectedly) to decreased growth and flower production. However, the seedlings of mycorrhizal harebells grew better than those from parents that were experimentally prevented from having that association. So the advantage of the fungal connection appeared in the next generation. Interesting!

Perceptive readers may well generate lots of follow-up questions from these brief notes!


…and some excitement!

After hearing about the flocks of migrating songbirds out on the wetlands, I ambled out there and found longspurs and buntings, but I missed seeing the gray-crowned rosy-finches. So the next day, I went out there to look again. After a long lonely stroll, I finally spotted my birds—a flock of small dark birds accompanied by a couple of buntings swirled overhead and swept down into the grasses. Yes! Although they were barely visible as they scuttled about in the bent-down grasses, they were surely rosy-finches.

I don’t see them very often—they usually nest in rock alpine tundra, scree slopes, and cliffs above timberline. The breeding range extends from Montana northward through much of Alaska to the Aleutians and Bering Sea islands. There are subtle differences in plumage among birds that nest in the Interior, coastal areas, or the islands—differing amounts of gray on the head and darkness of body plumage. The Bering Sea nesters are bigger and darker than the others, with more extensive gray on the head, and they can nest at sea level on those barren islands. Years ago, an invasion of gyrfalcons nearly wiped out the rosy-finch population on the Pribilofs, but the population gradually recovered. The island populations have an earlier starting time and a longer breeding season than the birds in the mainland mountains, and they often nest on buildings there.

Rosy-finches are socially monogamous and (unlike longspurs) the males are very attentive to their mates. Males don’t hold big, multipurpose territories but defend their mates and nests. The female builds the nest, accompanied by her mate as she gathers material, and the male sometimes brings nesting material to her. He guards her well from other males during the egg-laying period when she is fertile. Females incubate clutches of three to five eggs for about two weeks and their mates bring food to them while they do so. Both parents feed the chicks for two or three weeks. The chicks can fly when they leave the nest but are tended for a while by their parents.

Rosy-finches (and other finches too) can carry food in a pair of buccal pouches, located under the tongue and extending back to the upper throat area. Both seeds and insects can be carried this way, to be delivered to mates and chicks. Like many other finches, including crossbills, rosy-finches are attracted to snow or soil on which some animal has urinated; they’ll also sometimes come to wave-washed beach logs. They are after salts and perhaps other minerals that are in short supply in many seeds. These birds aren’t the only ones: butterflies also gather on urinated soil for the same reason; we call that behavior ‘puddling’.

Meanwhile, back at the ranch: I looked out my windows one evening and saw an adult northern goshawk hopping along the bank of the pond, intent upon a female mallard that swam in a narrow channel between melting ice and the bank. All the other ducks were gone, leaving her to her fate. The goshawk jumped that mallard from the bank, then from the ice, then the bank again, or the ice, at least twenty times. Each time, she dove with a great flurry of wings and splashing water, leaving the hawk with wet feet and feathers. Back and forth she swam, quacking, in that narrow channel, always staying in the same ten-foot stretch. When I looked more closely, I could see why—she had (sensibly!) chosen a stretch that was semi-protected by branches that prevented aerial attacks and limited the hawk to pouncing from the sides of the channel. Eventually the hawk left, still hungry, but the duck continued to vocalize for some time as she gradually settled down and then departed. Whew!

Summer comes

in praise of the season

It’s official now. Never mind what the calendar says; the fireweed flower buds are emerging from tall, leafy stems, and that’s the seasonal clock that matters!

A trip up the tram in mid-June encountered lots of snow across the trail, becoming too much for me just a little way above the cross. Even so, on the lower part of the trail, narcissus anemones, yellow violets, and Cooley’s buttercups were showing off, along with an alp lily, a few pixie eyes, one deep purple Alaska violet, and a few others scattered about. Fox sparrows, juncos, robins, and Wilson’s warblers sang.

Just ten days later, the trail was almost clear of snow as far up as I could see, although I found one old ptarmigan burrow with the usual fecal deposits, beside the trail. Going just a few levels beyond the hang-gliders’ wind-sock, I noted about thirty kinds of flowers. Now the Alaska violets were in full swing; buttercups and anemones still flourished and were joined by northern geranium, spotted saxifrage, roseroot, moss campion, fine displays of villous (woolly) cinquefoil, and many others. A friend reported that the glaucous gentians were blooming nicely, higher on the ridge. What a difference those ten days made!

Alaska violet. Photo by Deana Barajas

At the very end of June, on a low tide, a friend and I wandered out to some of the dredge islands in the wetlands off the dike trail. Sculpins scuttled away in the nearly-dry channels. A few hot, sunny days had made the lichen carpets on the islands dry and crispy, but they still offered a tapestry of varied color and texture. Savanna sparrows sang from the grassy areas and shrubs along the edges, song sparrows from the thickets, hermit thrushes from the spruces. Beach rye was shedding pollen, cow parsnip’s big, white inflorescences were platforms for nectar-sipping flies, and an angelica inflorescence was totally covered by tiny flies doing the same. Willow seeds freed from their capsules were floating about, sometimes getting caught on branches, making fluffy clumps. Mayflower and dwarf dogwood plants had established in some places, but they were small, pale, and without flowers, quite unlike the ones growing in forest. The little plant called sheep sorrel (an introduced species gone feral) had opened some of its tiny reddish buds, and yellow rattle (or rattlebox) was flowering too.

There was, of course, the usual accumulation of trash—spent shotgun shells, plastic jugs, beer cans, and what not. We had a big yellow litter bag, so there is less of that now. As we picked up half of a damaged plastic jug, we panicked a colony of ants that had built their tunnels under that convenient roof; we did what we could to give them a new roof of natural materials. Ants arrive out there when a winged queen with fertilized eggs wafts over the channels and sets up shop wherever she can find a place. Ants seem to be so uncommon here, that I get a bit excited when I find some.

A few days later, three friends wandered out the Fish Creek trail and perched for lunch on a beached log. We were amused by a pan-handling squirrel that came up behind us, clearly expecting some snacks. It got some, of course. Out on the exposed tide flats, an eagle stood quietly, no food in-hand, doing nothing in particular, but a mischievous crow dove at it repeatedly, even striking it occasionally, for no apparent reason except devilment.

We walked around to the end of the ‘island’ and looked out over the tide flats. Suddenly, a gang of fifty or more crows rose up and flew toward the trees behind us, making a tremendous racket, sounding very angry. The crows converged on one spot at the edge of the trees, clearly focused on something down under elderberry bushes and sweeping spruce branches, hollering and swooping down at whatever it was. Fifty crows can make a terrific amount of noise!

So, of course, we had to watch. The sharpest observer among us finally spotted a bird (or, rather, part of one), barely visible under all the brush. At first, all I could see was a small patch of gray feathers, surrounded by green elderberry leaves. But on the other side of those green leaves, close to the ground, I finally could make out a bird head—a glaring eye and a red-stained beak. That bird didn’t move while the crows were furiously mobbing it—yelling bloody murder and crashing into the vegetation around it. After many minutes, though, the hidden bird moved a few feet and stood up; now we could see the front of it—a belly marked with some dark, horizontal bars.

Putting the visible pieces of the harassed bird together, we determined that it was a peregrine falcon, a deadly predator of other birds, although we couldn’t see if this one held any prey in its feet. But mysteries remained: How did the gang of crows out on the tide flats know it was there? Did they see it come in or did a lookout in the trees notify them? Had the falcon captured a small bird or even a young crow, which would set off all the crows’ alarm systems?

Eventually, the hubbub subsided, although the crows still kept watch from perches in the trees. The falcon remained almost invisible in the thick foliage. We didn’t stay to see what might happen when the falcon tried to leave its leafy cover.

Flower colors

musings on the palette of summer

Just before the summer solstice, a little group of friends walked out onto Cowee Meadow. Although it was raining in town, out there, the sun was shining. The meadows were a blaze of color: pink shooting stars, yellow buttercups, and blue lupines covered acres with floral glory. While those species were dominant in the meadows, we counted over sixty species of flowers on our walk (not counting grasses and sedges). We did include the irises, which were just starting to bloom; in another week or two, irises will be the main show.

Among all the blue lupines were three or four individuals with pink flowers, and we’ve sometimes seen very pale shooting stars. On the upper beach, there’s the usual blue-flowered oysterplant, with a few white-flowered individuals—and even one plant that apparently made both blue and white flowers. Rare white-flowered geraniums and beach peas are also reported among the usual purplish ones, and some chocolate lilies have yellow (instead of brown) flowers. That made us wonder about the fate of these mutants—do they get visited by insects or are they reproductive failures?

While cogitating about flower color, we also commented that white flowers seem to characterize more of our native, local flowering species than any other color, although many of those white flowers are small and inconspicuous. There’s a fair number of species with blue/purple, yellow, or pink flowers, but red, orange, and green flowers are rare. However, white may not predominate in our alpine zones–It might be interesting to compare the frequency distribution of floral colors in different habitats and contemplate possible relationships with the available pollinator fauna (or other factors).

A common white flower on the Cowee Meadow trail is dwarf dogwood (bunchberry). It’s so common and familiar that it often escapes notice! That ‘flower’ is really an inflorescence composed of four whitish bracts surrounding a tight central cluster of actual flowers. There were many other things to look at on that hike, so I didn’t take time to inspect those dogwood inflorescences closely.

Photo by Kerry Howard

However, a few days earlier, I had done so on the Eaglecrest Lower Loop—higher in elevation, so the dogwoods were then less advanced and I could observe the seasonal progression of floral development. Some dogwood inflorescences were just opening and the bracts were small and green; the floral buds in the center were dark and tightly closed over the male and female parts inside. On more advanced inflorescences, the bracts were bigger and greenish-white, while the floral buds were still dark and closed. Then the bracts get bigger and whiter, and by the time they are fully mature, the floral buds are starting to open, exposing the sex organs to visiting insects. The flowers ultimately can open by themselves, but studies have shown than an insect visit can trigger floral opening and an explosive release of pollen. In either case, stamens catapult pollen vertically for several centimeters at very high speed, onto an insect or into the breezes. The pollen grains are not sticky, so high-speed release is thought to be necessary for adhering the pollen to an insect. Whether by wind or by insect transport, pollination is only successful when pollen arrives from a different dogwood individual, because this species is self-incompatible. After pollen is ejected, the pollen-capturing surface of the stigma increases, ready to receive incoming pollen. However, fruit-set generally seems to be low.

Another white-flowered plant was blooming profusely in the meadow along the Lower Loop trail: three-leaf goldthread.  This flower looks nothing like the flower of the related fern-leaf goldthread that mostly grows in the forest. The flower is comprised of several white sepals surrounding the sex organs and five (sometimes six) tiny golden trumpets that are modified petals offering nectar to visiting insects. Although I saw no insects visiting a group of open flowers, I watched a small fly working assiduously for several minutes, trying to gain entry into an almost-open bud.

There must be good stories behind the evolution of flower colors and shapes; I wish I knew them!

Tree sparrows and bluebirds

…a scrapbook of spring bird stories

In the early part of April, there were sometimes two dozen mallards on my mostly-icy home pond. There was one male who was not fully ‘dressed’—while all the other males in the group had long since acquired their glossy green heads, rusty chests, and so on, this one was only part-way into the typical breeding dress. Was he just a very late hatchling last fall, lagging in maturation, or did he have a metabolic deficiency of some sort?

By late April, the mallard mob had dispersed, leaving one pair in charge of the now-ice-free pond. The male was seriously aggressive toward a visiting solo male, defending both his female and, perhaps, the seed-fall from the feeder hanging over the water.

Out at Eagle Beach, a mixed crowd of six species of waterfowl moved offshore, as a gamboling puppy approached along the water line. A scattering of American pipits foraged over the tideflats, readily distinguished from other small, brown songbirds by their characteristic gait—they walk and run, rather than hop. At the edge of a mown grassy area, I found a mixed flock of juncos, both Oregon and slate-colored, and American tree sparrows. They were all scouring the turf for food and flitting hastily to the surrounding brush when startled. I hadn’t seen a tree sparrow for ages, so this was fun.

Tree sparrows nest way up north, on open tundra with scattered shrubs and thickets of willow, birch, or alder. The nest is usually on the ground, and the female incubates the eggs for about twelve days. Nestlings are fed by both parents and stay in the nest only about nine days, then hopping out to follow the adults on foot. Tended by the parents, they begin to fly when they are about two weeks old. Tree sparrows feed on the ground and also by hopping up to grab seeds from the seed-heads of low-growing plants. In season, they also feed in trees, to eat small berries. This species has not been very thoroughly studied, so there are lots of details to discover.

Through much of April, there were reports of migrating mountain bluebirds on their way north, seen now here, now there, and in some other place. I tried several times in several places to find them, but they continued to elude me. Then, the day after finding the tree sparrows, I strolled out toward the Boy Scout beach. In addition to seeing a fox sparrow, two Townsend’s solitaires, some Bonaparte’s gulls, and a flock of snow geese, I encountered two friends who were intently watching a patch of dead cow parsnip stalks and a few little spruces. They had found a male bluebird, which was foraging in classic bluebird style: watching from an elevated perch, just a few meters above the ground, then dropping down to the ground to pick up an insect and flying back up to an observation perch. Later, I spotted a female bluebird in the same area, and she too was foraging in the traditional way. So, at last, I had found them.

Photo by Kerry Howard

Bluebirds have other foraging techniques too. Sometimes they hover a couple of meters above the ground to scan for bugs or occasionally chase bugs in the air. In the non-breeding season, they add seeds and fruits (of many species) to the diet. To augment calcium in the diet, egg-laying females may eat bits of egg shell or snail shell to help build the shells of developing eggs, and nesting females may feed shell bits to the chicks to help develop good bones.

Mountain bluebirds nest primarily in the mountains of Montana, Wyoming, and so forth, but some of them range more widely, coming in small numbers to northern B.C., Yukon, and interior Alaska. They are cavity nesters, loving old woodpecker holes but also nesting in cliff crevices, nest boxes, and sometimes other human structures. They favor habitats with short grass and scattered trees or snags offering nesting cavities. They are reported to arrive early on the nesting ground, probably because suitable cavities are limited in number, so the early arrivals get the best choices.

Male bluebirds are territorial, defending an area around potential nest sites, and females can then choose among them. Nests are built primarily by females, often guarded by their mates against potential predators and intrusions by other males. Females incubate for about two weeks, usually fed by their mates, and they brood the tiny hatchlings. Both parents feed the nestlings, which stay in the nest about three weeks, and the fledglings.

Mountain bluebirds are socially monogamous, meaning that they form pairs but both partners may go philandering–seeking occasional matings outside the pair bond. This arrangement turns out to be rather common among species that were once thought to be strictly monogamous. A bluebird pair bond typically lasts for a season, including replacement nests or second nests, but a pair does not necessarily stay together the following year.

That blue color that we love is not produced by pigments but by the micro-structure of the feather barbs; both UV and blue wavelengths are reflected. Males within a population differ in the amount and reflectance of their plumage. Now things get more intriguing: In two studies, done in two different geographical areas, brighter males were more likely to go philandering, engaging in more extra-pair copulations, than less-brightly colored males. Their brightness was not related to age or body condition. In one of those two studies, the more colorful males sired more of the chicks in their own nests and more extra-pair chicks. In the other study, the more colorful males were also early nesting and achieved more extra-pair copulations, but the paternity of chicks in their own nests was not enhanced, compared to less colorful males nesting later. Thus, in both cases, the payoff for bright coloration was greater numbers of offspring sired, and potentially greater evolutionary fitness, although the size of the payoff differed between the two areas.

Beaches and tideflats

sightings and discoveries in a sudden spring

Several sunny (!!) days in a row in mid April. I’ve now hacked most of the ice off my driveway and trimmed back the piles of snow on my terraces from two feet deep to a few inches. Mallards are thronging to my pond, which has ice only in the middle, with wide open channels around the edge. I hear juncos, ruby-crowned kinglets, varied thrushes, and nuthatches in my yard. Maybe it’s really spring!

All that sunny weather drew me out to soak up the sunshine. On Boy Scout beach, while a group of friends perched to have lunch, a beautiful, huge queen bumblebee checked us out—she particularly liked a certain blue/purple jacket, to the consternation of the human inside. Those bees just love that hue and come buzzing around, as if it were one huge flower. They usually figure things out fairly quickly and go away.

On another day, I visited Eagle Beach and found a partial skeleton near the high tide line—one forelimb and a body sans skull. The bones were quite well picked-over by scavengers. I was puzzled—they clearly didn’t’ come from a deer or a seal; otter and bear were quickly ruled out; so who was it? A little bony detective work on the internet later found a likely prospect—a small Steller sea lion. The clues were the short, stout bones of the forelimb, a curve at the back edge of the shoulder-blade, and the lack of well-developed flanges (neural spines) on the outer part of the vertebrae. That tentative ID was later confirmed by a photographer-friend who had seen the carcass. The forelimb was especially interesting—the upper arm bone (humerus) was very short (maybe five inches long); the two lower arm bones (ulna and radius) were not quite so short but quite thick. That morphology might be related to how they use their forelimbs on land, hoisting the heavy body over the ground.

A couple of days later, I walked the dike trail with a friend, and the place had really come alive. Ruby-crowned kinglets serenaded us all along the trail, helped by a song sparrow or two. Golden-crowned sparrows scratched around in the thickets for fallen seeds and occasional bugs. Four pipits explored a channel left dry by the low tide. Robins were scattered widely over the grassy tideflats, foraging, and scolding when disturbed. A male yellow-rumped warbler hawked for flying insects over a pond and a female flitted about in a semi-dry channel after bugs that apparently jumped around. Two shorebirds got away from me but a greater yellowlegs was poking around in some shallows. All that warm sun had made green shoots of several species begin to rise from the soil, and on the trees a few leaf and flower buds were ready to open.

The next day I walked Eagle Beach again. Things were very quiet until a northern harrier coursed over the flats, scattering a few small birds and provoking the geese into vociferous protests. Harriers often cruise the beaches at this time of year, no doubt hoping to nab migrating shorebirds. Although I’d missed (sadly) the migrating mountain bluebirds reported from several beach areas, I did score a minor coup—a Townsend’s solitaire was hanging out in the brush at the edge of the big meadow at Eagle Beach, making occasional forays into the open in pursuit of small flying insects. This species typically nests in the Interior, often in open forest habitats, placing its nests in cutbanks and steep rocky slopes; the nests are on the ground but usually have some overhanging rocks or stumps.

Townsend’s solitaire. Photo by Scott Ranger

A few more fine, sunny days, and there were blueberries in flower, skunk cabbages up and open for their female-phase flowers, a flock of snow geese on the wetlands, and reports of wood frogs chorusing in a pond over on Douglas. It’s happening!

February scrapbook

warm and bright observations in an icy world

Winter finally arrived sometime in early February, with good snow on the ground and very cool temperatures. I’ve lived here for three decades, so I’m quite well acquainted with Juneau’s local microclimates—it’s often warmer, wetter, and windier downtown than it is in the upper Valley where I live. But I recently saw what seemed to be an extreme case: as I drove Out the Road one morning, I left my house at a temperature of minus six degrees (F), then the car thermometer registered plus thirteen, dropped quickly to minus two, and rose again to plus fourteen degrees. That’s a twenty-degree span in fewer than twenty minutes. Extraordinary.

Along the way, I passed a place where a thin blanket of white mist lay over an estuary and shallow inlet. We often see this phenomenon in cold weather and sometimes call it ‘sea smoke’ or ‘steam’. But it’s not steam…steam is hot water vapor, and it’s not really smoke, either…not full of organic particles and carbon dioxide. Whatever the right name is, the cause is well-known. Liquid fresh water cannot be colder than thirty-two degrees (or it would become ice). So the surface of the estuary was warmer than the frigid air and water was evaporating. When that rising water vapor encountered the cold air, which holds less water than warm air does, it condensed into small droplets that hung over the water surface in thin mist.

I met a friend at the Point Bridget trailhead and we set off to see what we could find. The best find was the trail of an otter, bounding and sliding over flat ground and out onto the frozen beaver pond. Even on the flat, this otter was sliding as much as eight feet before gathering itself for another bound and slide. Wouldn’t that be fun to do! Blowing snow had drifted into some other tracks, but we found those of porcupine, moose, and a deer or small moose; red squirrels had made new highways under some of the trees.

A stiff breeze was churning Lynn Canal into a froth and big waves were roaring onto the beach where we look out at Lion’s Head. By the time we got there, it was afternoon and the wind was increasing, as it often does then. So the beach log where we often perch for lunch was not very hospitable. Even behind the beach berm, the wind was making the emergent tall grasses lie almost flat on the snow. So we found a windbreak in a sunny spot for a comfortable lunch.

Home again, with temperatures a relatively balmy plus sixteen degrees. The birds were active on the feeders, among them ‘my’ pair of red-breasted nuthatches. They brought two youngsters to the feeders one day last summer but they have apparently stayed on their territory for the winter. Each pair is socially monogamous; there apparently have been no studies of extra-pair matings (which are common in many other birds). Nuthatches defend their territories from other nuthatches; the male is especially vigorous in defense when the pair is excavating a nest in a dead tree. They also defend the nest cavity from red squirrels, which are potential predators of eggs and chicks.

Nuthatches have the odd habit of putting sticky conifer resin around the opening of the nest cavity. It is thought that this helps deter predators. One study found that more resin was placed around the nest entrance right after a face-off with a squirrel. Rarely, however, this tactic backfires, and one parent gets inextricably stuck in the resin and dies.

After the nest is built, females incubate five to eight eggs and the male brings her food. Incubation takes about twelve days and chicks stay in the nest for almost three weeks. Sometimes the male joins the female in the nest during incubation and brooding very small chicks. After the chicks fledge, the parents feed them for another two weeks and then the youngsters sometimes stay with the parents for many weeks, or they may become independent and disperse. Most nuthatches probably live only a few years; the maximum known lifespan is just over seven years.

Nuthatches forage by walking up and down and around tree trunks and big branches, especially in winter, presumably because dormant arthropods lurk in the crevices. They can walk head-first down a tree trunk and even walk upside down underneath a branch. They have a very short tail, not usable for bracing again the wood as woodpeckers and creepers do. Having a relatively long hind toe helps them scamper down and sideways. Outside of the winter season, they also forage on twigs and leaves, even on the ground sometimes, and occasionally catch insects out of the air.

Photo by Gwen Baluss

Captured food is often cached in holes and crevices, sometimes covered with bits of lichen or bark. A big item is wedged into a crack and then hacked into smaller bits (unlike chickadees, which hold such items in their feet). In fact, their English name may have originally been nut-hacker. At a seed feeder, nuthatches can be very choosy, carefully selecting the largest and heaviest items.

Little appears to be known about how they manage in extremely cold weather. They do join mixed-species foraging flocks in winter, along with chickadees, kinglets, and other small birds. Presumably their insulation is quite good, but they don’t seem to roost communally or have elevated metabolic rates then (as some other birds do). More questions to be answered!

Three fungal curiosities

a tree-swallower, a “bleeder,” and a “nest”

This essay is about an eclectic assortment of fungi, my choices being based entirely on happenstance and whim.

One September day on the Outer Point trail, we spotted a very large, yellowish patch on a tall alder snag. That patch covered most of one side of the snag; at a guess, it may have exceeded ten square feet. At first glance I thought it was a huge crustose lichen, but no, it was a fungus. On certain places on this expansive crust, there were small ridges like miniature conks, and on their undersides were numerous pores where spores would be produced. The crust has covered mosses and engulfed the stems of licorice ferns.

Photo by Jennifer Shapland

I went back to look at it about ten days later, and now the surface featured many shallow furrows that had turned brown. The furrows were four or five millimeters wide and several inches long, crisscrossing the flat surface of the big fungus. Were they the work of slugs or land snails, grazing their way along? No, there were no marks of the scraping radula or tongue. A few days later, another observer suggested that wind-bent branches hit the fungus. No, when I tried it, small branches striking the surface didn’t leave furrows like that. A few more days later, we finally noticed that all the furrows occurred between human knee height and head height. Then I found that I could mimic the furrows very well with the flat of a fingernail. So we—finally!– concluded that these furrows are just graffiti. Much less interesting than slug trails, but perhaps closer to truth. ‘Twas a shame to deface such a beautiful organism.

What is this magnificent, hall-of-fame specimen? It seems that nobody really knows! It might be X or maybe Y, or something else altogether. Several mycologists have been consulted, with no concrete results. A sample sent to a lab for DNA analysis might yield a solid answer.

A strange fungus sometimes seen near the visitor center, among other places, is called the bleeding tooth fungus (Hydnellum peckii). Its name is not about bleeding teeth; it’s a tooth-fungus (with spore-bearing ‘teeth’ instead of gills or pores) that seems to ‘bleed’. The immature cap is white, but sometimes there are little pools of red fluid on the surface. Another name, perhaps for the more squeamish observers, for this critter is strawberries and cream. As far as I can tell, nobody really knows why those pools form on the cap. The present idea is that it’s a way to get rid of excess moisture, as some other fungi and some plants do by exuding droplets of water. But why are the pools red? Is the color just an incidental by-product of some metabolic process?

Photo by Jos Bakker

This fungus is mycorrhizal, forming connections with the roots of conifers and exchanging nutrients. The cap turns dark as it matures and produces spores. The stalk is thick and short, so short that the cap is often semi-buried in moss and debris. That raises the question of how the spores get dispersed from under the cap.

Yet another curiosity is a bird’s nest fungus (Nidula candida), a decomposer living on dead wood and rotting vegetation that is quite common around here. It earned its name from its appearance: the mature, reproductive form features a small (roughly one cm) cup containing several little round (somewhat flattened) objects. So it resembles a miniature bird’s nest with eggs. The ‘eggs’ contain spores. The cap is ingeniously built so that a raindrop can splash the ‘eggs’ out of the cup to a distance of a meter or more. The ‘eggs’ of some bird’s nest fungi (but not ours) are ejected with long, sticky threads, which catch on vegetation as they fly off. Eventually the ‘eggs’ deteriorate, releasing the spores. The spores germinate, producing stands called hyphae; two hyphae of the right mating type can merge to develop a nest-like fruiting body. Splash-cup dispersal mechanisms are uncommon means of spreading offspring around, but they are known also from some plants.

Photo by David Bergeson