Winter wanderings

In early January, the ice on the ponds in the Dredge Lake area was good and solid, although there were isolated spots of open water where upwellings slowed the formation of ice. I traipsed around some of the trails and ponds, finding tracks of shrews, hares, and a mouse. Otters had slid over a beaver dam and then up a frozen slough, no doubt hoping to find a fish or two.

One day in mid-January, a friend and I explored a frozen pond, walking on snowshoes to spread out our weight, in case of a spot of weak ice. A little snow was falling, so it was a beautiful walk.

Beavers had made a small food cache near their lodge, including some hemlock branches. There were lots of spider webs and long, trailing silk threads used by airborne spiders. We wondered if any critters, in addition to some spiders, eat that silk to recycle the protein.

Around the bases of several trees at the edge of the pond, we noted the tracks of a small bird, probably a junco. It had apparently inspected each tree base quite closely, possibly picking insects from the spider webs that curtaining the gaps between the upper roots or searching for stray seeds.

A vole had crept out of one bank of a frozen rivulet, crossed he ice, and scuttled back to where it came from. My companion had observed such behavior in other places when the animal was seen to be a red-backed vole, so we assigned that perpetrator to those tracks. Deer tracks crisscrossed the pond ice, and deer had been feeding on the witches’ hair lichens that grew on small trees at the pond edge. My sharp-eared companion heard a brown creeper, which we soon saw as it hitched its way up a spruce trunk.

Many of the alders in this area had neither cones from last summer nor any male catkins for next spring. This was unlike other alder stands we’d seen, so we wondered why this stand was evidently reproducing very poorly. Perhaps the high level of water in the pond was too much for them.

We also noticed that here and in some other places the alders had retained many of their dried and shriveled leaves, instead of letting them drop to the ground. Blueberry shrubs sometimes do this too. In other regions, oaks, beeches, and other trees also retain many of their dead leaves throughout the winter. The term for retention of withered old flowers or leaves is ‘marcescence’. Marcescent leaves have attracted a good deal of speculation about why these plants do this, such as deterring deer and moose browsing, trapping snow for release of moisture in spring, or delaying decomposition until spring, when nutrients are most needed for growth. However, apparently very little investigation has explored those ideas. In some cases, particularly when marcescence is occasional and not regular, the retention of dead leaves may just happen incidentally because the weather suddenly changed in a way that prevented the usual mechanism of leaf-drop (formation of the cut-off or abscission layer at the base of the leaf).

A few days later, along the Auke Lake trail, (and later in other places) we noticed that many of the blueberry bushes had small galls on the twigs, often at the bases of marcescent leaves. The galls are really quite small, and I have to wonder how many times I have walked past them without noticing. They do seem to be more conspicuous against a snowy background…Some blueberry galls are made by midges or wasps, but these did not fit the descriptions of such galls, so the makers of these galls remain to be determined.

Toward the end of January, I went with a friend on the Pt. Bridget trail. Near the trailhead, we found a place where a weasel (I think) had fossicked about in the mud at the bottom of a hole in the snow, and come up to leave a string of its small, muddy footprints on the snow, before diving back down under the deep snow in a new spot. Somewhat to my surprise, the lower branch of the trail, along the edge of the big beaver meadow, was quite passable, provided one didn’t mind a couple of inches of water here and there. A moose had used the trail too, taking advantage of a deeply trenched part of the path—and a small wooden bridge—to avoid some of the post-holing that was required in the rest of the meadow. The bible-camp horses had left ample evidence of time spent on this side of Cowee Creek, on the beach fringe as well as in sheltered places under the conifers. Pawing away the snow and stirring the long, dead grasses, they also had clearly been looking for precocious green shoots under the snow…and had found a few.

As we left the area near the cabin, my companion spotted an owl, probably a short-eared owl, as it swooped down to some bare ground next to a tidal slough (the tide was out). It was probably trying to catch an unwary rodent, but we could not be sure it was successful. It soon flew up into the nearby trees, changed perches, and eventually took off across the wide meadows, screened from clear view by tall spruces.

A day or two later, when Plan A for a beach-walk was foiled by ferocious north winds on Lynn Canal, another friend and I eventually found a sheltered beach near Amalga Harbor. Moving slowly and quietly, we managed to share the beach with a trio of common mergansers that paddled slowly along the tide line. Then they all hauled out and snuggled up in a close-packed row to sun themselves.

I have learned a new word for verbal bric a brac like that found in this essay: bricolage. ‘Tis a very useful word for assortments of diverse things brought together in some more or less unifying way. There may be more bricolages here in the future.

Tracks in December

tracings of life in an unusually warm winter

A warm, very wet spell in early December made the lichens and mosses all perky and colorful. Beavers left their distinctive foot marks in a thin dusting of snow and swam out around their winter caches of twigs, tail-slapping when we passed by. In a ‘real’ winter, they would be tucked up into their lodges, snoozing a lot, talking quietly with their offspring, and occasionally nibbling a twig from the cache. The kits of the year, however, would be chewing twigs all winter long, as they continue to grow. Bears were out and about too, mom and cub leaving their tracks near Dredge Lake, instead of entering into serious hibernation. That entails a profound reduction of metabolic rate, shutting down digestive processes, and very little activity inside the den, quite a contrast with beavers.

Then, in mid-December came a lovely and welcome snowfall, just a few inches at sea level. It wouldn’t last, of course, in this time of warming climate, so I dug up my snowshoes and headed to Eaglecrest. There the snow was maybe a foot or so deep and just right for poking around on a day when the lifts weren’t running. Snow was falling thick and fast, quickly covering any little tracks of mouse or shrew. But under the trees were prints of snowshoe hares. A small-footed canine creature had run across a wide open area, leaving a long, straight line of well-spaced prints. There was no evidence of any human anywhere nearby, so I guessed that a coyote had raced along. But very few critters made themselves visible—a porcupine that seemed to think that if it could not see me, then I could not see it; and one flying insect, probably a stonefly. Nary a bird to be heard or seen not even a hopeful, attendant raven.

A couple of days later, a nice little cold snap meant that even at sea level, there remained a few inches of snow cover. I went out the road to some meadows, where I plonked along on snowshoes—a convenient way to deal with snowy humps of frozen grass. Oddly, there were no shrew tunnels to be seen, nor any squirrel tracks, and again not a bird could be found.

But otters had been quite busy. They had fossicked along a tiny rivulet, trampling some spots quite flat; there were more than one of them, apparently, so perhaps a family of mom and well-grown pups. I lost their trail when it went under the trees where there was no snow. However, a few minutes later, I encountered their characteristic slide marks where they had crossed a snowy, open area, pushing off strongly with the hind legs and gliding smoothly even over flat ground. This is probably more fun than stomping around on snowshoes! A bit farther on, otters had come up out of a tiny stream and snuffled all around the nearly buried ends of several low, trailing spruce branches. What was going on there, I wonder.

Some days later, I looked for tracks in another meadow out the road, but there had been little recent activity. A couple of squirrels had explored the meadow edges, out of the trees and back again, diving under humps of bent-over grasses. Before the last little snowfall, porcupines had trundled over the meadow in several places, on their usual meanderings. They seem to travel quite extensively, perhaps in search of just the right twig to nibble (?). Along a small creek, some critter had burrowed into the bank in several spots—possibly an otter.

Surprisingly, there were no little shrew-size grooves on the surface of the snow, no tiny holes where a shrew dove under the white blanket. Yet this was a meadow that, in previous years, had been laced with trackways of shrews. One shrew had even taken a dive off a vertical mudbank and gone skittering over a gravel bar in a creek. But where are all those shrews now?

A fluttering on the creek-bank caught my eye and eventually turned into a dipper. This bird was foraging along the water’s edge but apparently found little of interest, because it soon took off, upstream. That was the only living animal to be seen, except for one red squirrel crossing the creek on a broken-branch bridge.

Later that day, on another stream, I checked a long-occupied beaver lodge. There were no signs of recent beaver activity here, although the lodge may be currently occupied. However, other woodland folks were interested in the place: porcupines and mink had visited on more than one occasion in recent days. Was this perhaps a multi-species condo? It wouldn’t be the first time that happened.

The slanting light of midwinter that stabs one blindingly in the eye at certain times of day on Egan Drive, did some beautiful things out by the meadows. Some conifer-clad hilltops were brilliantly lit, contrasting with darker slopes below. Light mists collected in the valleys caught the light rays and turned golden. Overhead, some dark clouds gathered amid some white fluffy ones, but bright rays came through the many unclouded areas, where blue sky was a cheery sight.

September leaf colors

bright highlights in an evergreen landscape

fall-color-by-bob-armstrong
Photo by Bob Armstrong

Juneau ‘leaf-peepers’ don’t have to travel to the upper Midwest or New England for a view of lovely fall colors. This fall there is a pretty good show right here. Although the somber greens of the conifers dominate the landscape, a good color spectrum from yellow to orange to red and pink and even purple can easily be seen.

Returning to the Valley from a hike out the road on a drizzly day when the clouds sat low on top of Benjamin Island, I saw several places along the highway where the golden-yellow leaves of cottonwood seemed to light up the whole area. Patches of fireweed provided flaming scarlet mixed with other shades of red. Across the highway from the Methodist camp, the roadside shrubs and small trees made a splendid pastel expanse of glowing yellows and pinks. Dogwood shrubs sometimes offered a spectacular array of reds and the broad yellow and gold leaves of devil’s club brighten the understory. Highbush cranberry can do it all–yellow, orange, bright red, pink—sometimes even on a single leaf. Closer to the ground, dwarf dogwood and low-bush blueberries do the reds and purples.

The visual color show happens when the leaves of deciduous plants senesce (deteriorate with age) in the fall. The vascular connection between leaf and stem is gradually closed, shutting off the supply of water and nutrients to the leaf and slowing the passage of materials from the leaf to the rest of the plant. Photosynthesis slows and the green pigment (chlorophyll) that does the work of making carbon dioxide and water into carbohydrates breaks down. As it breaks down, leaves lose the green color and the yellow and orange pigments are exposed; they were there all along, capturing light energy and passing it on to chlorophyll for photosynthesis. Chlorophyll is broken down by complex processes that are still being elucidated, but apparently some of the break-down products are still photo-reactive and perhaps potentially damaging, unless quickly de-activated or protected in some way. Meanwhile, the plant retrieves any remaining carbohydrates and nitrogen-containing products of breakdown before the vascular connection closes completely and the leaf drops.

What about the red colors in fall foliage? In most plants, they come from anthocyanins, synthesized toward the end of the season during leaf senescence, using some of the carbohydrates made by the leaf. Anthocyanins account for the reds, pinks, and purples—the hue depending on acidity within the leaf, which depends, in turn, at least partly on the accumulation of carbon dioxide in the leaf when photosynthesis is slowed. It is thought that warm sunny days and cool nights in fall favor the development of red foliage, so our unusually nice September weather might have contributed to the color show this year. I think we can see this effect sometimes in a single highbush cranberry shrub: the side of the bush exposed to light and dropping temperatures at the edge of the woods can be far more colorful than the other side of the same bush that is more protected under the tree canopy.

The functions of anthocyanins have been a subject of much discussion in the literature, but it appears that in autumn leaves they may have a protective function, defending the last days of photosynthesis and protecting from the possibly unstable, over-reactive products of chlorophyll breakdown from too much sun. There may be other physiological functions as well, still to be described.

Many questions remain. For instance: Why do some plants produce only yellow autumn leaves and not red ones? Do they have some other way of accomplishing whatever the anthocyanins do? An interesting comparison comes from quaking aspen, a relative of cottonwoods, in which some clones do make red or orange leaves. Also, willows usually make yellow leaves, but occasional some willow trees make lots of red leaves. Do they all have that capacity but just aren’t triggered to make red, or do only some willow trees have the capacity? And there are the alders, whose leaves invariably just turn brown. And a fundamental question: How does a plant decide when to shut down photosynthesis—there are easily observable differences among individuals of the same species, some retaining green leaves much longer than others. Stress from drought or insect attack might encourage a particular plant to shut down for the season, but what, specifically, are the mechanisms of this response?

Then there are the ferns, for which I have found little information about fall colors. But there is considerable observable variation. On one walk, there were wood ferns with whitish fronds, bracken with dark or light coppery fronds, and lady ferns all black, while in another area, lady ferns were tawny.

There’s no end to natural history questions; one answer just leads to another question! What fun! If we knew it all, there would be nothing left to provide surprises and discoveries.

September

delights of a season of slowdown

In September, the natural world slows down. The days get shorter and shorter, bird song diminishes to next to nothing, marmots are hibernating and the bears soon will be. Most of the wildflowers are done blooming, although a walk above the tram in the middle of the month revealed the last few flowers of six species. And the alpine zone is where we find our best fall colors: various shades of red on dwarf dogwood, avens, and lowbush blueberries, gold and russet on deer cabbage.

Nevertheless, on one day in mid-September, I enjoyed sightings of two kinds of critters that I don’t see very often.

Rusty-Blackbirds-by-bob-armstrong
Photo by Bob Armstrong

There were three rusty blackbirds on the shore of Mendenhall Lake, foraging over the wet sand and in the shallows. Rusties breed all across the boreal forest of North America and winter chiefly in the southeastern states. Even though Southeast Alaska is hardly on a direct route to the usual wintering area, I see them during the spring and fall migration seasons, sometimes by the ponds in the Dredge Lake area, occasionally elsewhere, but always in small numbers. Sadly, those numbers are likely to get even smaller: the number of rusty blackbirds has dropped dramatically in recent years, probably for several (undetermined) reasons.

Rusty blackbirds in Alaska often nest in wetlands and near ponds in dense, small black spruces, where nesting success is good, or in willow shrubs, with less success. Unlike their marsh-nesting relatives (such as red-winged blackbirds), they are usually monogamous. But similar to the other blackbirds, females do the tasks of incubating eggs and brooding young chicks. Blackbird males pitch in to help feed the chicks (but polygamous males commonly help mostly at the nest of a primary female; secondary females get less help).

In the nesting season, rusty blackbirds feed mostly on aquatic insects, including dragon and damselflies. During the rest of the year, the diet also includes seeds of many kinds and fruit. I was fascinated to learn that rusties sometimes kill and eat other birds.

The other critter I don’t see very often was Milbert’s tortoiseshell, a beautiful butterfly whose deep brown wings are banded with orange and yellow and adorned with red spots on the leading edge. All the color is on the dorsal surface, visible when the wings are spread. The ventral surface of the wings, visible on the folded wings, is more camouflaged, looking perhaps like dead leaves or bark. The one I saw was foraging on yarrow flowers—the only flower still in bloom in that area.

This butterfly overwinters as an adult, tucking into crevices in houses or trees, and emerging again in early spring. Batches of eggs are laid on nettles, which are the chief food of the caterpillars. (We could use more of them on the lower reaches of the Granite Basin trail!) Young caterpillars often forage in groups, but older ones are more solitary. They pupate in a folded leaf. When they metamorphose to the adult stage, they forage on nectar of many flowers, as well as sap and rotting fruit. In parts of North America, there may be two broods of caterpillars each year, but I doubt that there is more than one per year in Alaska. The one I saw was surely getting ready to hibernate, filling up the tanks, as it were, to last through the winter.

Addendum: As I strolled down to the beach below the pavilion near the visitor center, I stopped to watch the bear called Nicky and her little cubs. They trotted along the lowest pond on Steep Creek, where a few coho were jumping, waiting for enough water to allow them to ascend the creek. I don’t get to see Nicky very often either, so this was a happy sighting. The cubs looked pretty healthy but still very small…they will need their mom to catch some of those coho, so they can get fat enough to last the winter. But even Nicky, an expert fisher, can’t catch very many until there is enough rain to raise the water levels so the fish can get up into the stream itself. I have to hope for rain!

July Fun

a ridgetop celebration, an orchid search, and a visit from a black bear

Two Parks and Rec hiking friends share a landmark birthday this year and decided to celebrate with a summertime party on Juneau Ridge. Some of the hikers have better legs than others, and they walked up the steep trail, while those with legs that have seen better days took the easy way up, thanks to Temsco and Coastal helicopters. On a beautiful day in July, the party gathered at the top of the trail and celebrated with lots of cookies, cake, smoked salmon, fruit, and chocolate.

We milled around, chatting and eating and enjoying the brilliant sunshine and long-distance views up and down the channel. The area at the top of the trail gets a lot of traffic because it provides several suitable spots for helicopter landings, as well as a resting place for up-coming hikers. So the end of the ridge is heavily trampled. Nevertheless, in between the rocks and rubble and tramplings, my casual survey found thirteen kinds of wildflowers in bloom. Admittedly, they were not tall or lush on this storm-ravaged and sun-parched ridge-top; they were small–but sturdy and tenacious. I particularly remember one little monkshood plant standing all of four inches tall, bearing a single perfect flower of intense purple.

Looking down from the ridge, we could see several lovely, clear ponds on the sides of the hill. I don’t know what invertebrates might live in those ponds, but two shorebirds that came to visit did not stay long…

Party over, some hikers trekked along the ridge to Granite Basin, thence to the Perseverance trail, some went down the steep side of the mountain to the trailhead, and still others floated down in the friendly helicopters.

The next day, I ventured partway up Ben Stewart on a miserable trail that is nothing but mud, rocks, and roots. Parks and Rec hikers were headed for the top, but my goal was just the beautiful valley to the north of the peaks. There was lots of cotton ‘grass’ (really a sedge), some butterworts (one of our insectivorous plants), and leatherleaf saxifrage in the meadow, bordered by stands of copperbush and small conifers. A little creek meanders across the valley floor. On other visits in previous years, the creek had attracted dippers and hermit thrushes. This time, two shorebirds sailed in, poked around a bit, and took off—rising higher and higher until disappearing over the treetops. A fuzzy photo enabled one of our local ace birders to say that these were solitary sandpipers.

A couple of days before the big party, a little group of friends strolled up Gold Ridge from the tram. Among other things, we were looking for frog orchids, which had been easily found the previous week. But this time, we found only one in bloom. Some taxonomist presumably thought that the flower looked a bit like a frog, although that takes considerable imagination. I would love to know who pollinates these small green flowers (it’s not frogs!).

On the way down from the crest of the ridge, we spotted a ptarmigan family with chicks, so we all stopped to watch. The whole family—papa, mama, and about eight chicks—puttered along down the trail nipping at bugs(?) on the vegetation. After a few minutes, the male and some of the chicks scuttled off to one side and down a bit, and we heard him ‘growl’ a few times. Meanwhile, mama and the rest of the brood leisurely took the next switchback for several yards before finally stepping off and down, presumably to bring the family back together again.

These were willow ptarmigan, the only grouse-like bird in North America in which fathers get involved with parental care. I have to wonder how it happened that only this one species evolved this behavior! This male had molted out of his reddish upper-body plumage and only traces of red remained; otherwise he was in good camouflage plumage.

Earlier in July, I walked with a friend along the bluff trail on the west side of Douglas. We spotted a young red-breasted sapsucker just over the edge of the bluff, tapping on a tree. Creeping closer to get a better look, we could see it was making sap wells in the bark of an alder. Not a very orderly array of wells, but perhaps that happens with more practice. (That’s how this woodpecker got its name, of course; it makes holes in the bark and the sap oozes out, so the sapsucker can lick it up with its brushy tongue.) I also spotted a brown creeper, hitching its way up a tree trunk, but it flitted to another tree and totally disappeared—something that brown creepers do very well..

Back at home, I had a little excitement too. I chanced to look out a downstairs window and saw a large black back trotting along under the deck. A juvenile black bear, probably recently kicked out by its mother, was prowling the neighborhood. This one stood up to sniff the bird feeders that are hung well out of reach and, tried twice to climb the corner of the house to reach the deck (a noisy process). Then it came to the window in front of my computer and left messy paw prints all over the glass as it peered in at me.

From there, it went down to the pond and scared the brood of mallards that was foraging there, crossed the creek below the pond, and headed for the campground. What fun!

Sheep Creek Valley

nest-building, a song chorus, and a wildflower show

In early June, Parks & Rec hikers went up the Sheep Creek trail on a day of fitful rain showers and intermittent sunshine. This is a favorite trail, but it was clear that the trail could use some work! The uphill portion of the trail is seriously eroded by water coursing down the trail. The long traverse below the road is cut by deep erosional gullies and the edge of the trail is collapsing in spots. Along this stretch, cow parsnip overhangs and obscures the trail. Once in the valley proper, the going is easier, although several wind-shattered cottonwoods and sagging willows lie across the trail and there are more erosion cuts. Some of these things are easily fixed, while others are significantly more challenging.

This was a good time to go up into the valley, because it is rich in nesting, singing songbirds. Even though the P&R summer hikes begin well after the early-morning chorus of bird song (and my hearing is not as good as it once was), I identified the songs of twelve songbird species, plus hooters on the hillsides. One species, in particular, was a treat: Swainson’s thrushes commonly nest up there but they arrive later than the others; I don’t usually hear them until June. By that time, robins and fox sparrows are feeding chicks and juncos have fledglings.

swainson's-thrush-by-bob-armstrong
Swainson’s thrush with nest material. Photo by Bob Armstrong

Swainson’s thrushes nest all across northern North America and down along the Rockies. They spend the winter mostly in southern Central America and northern South America, although some go as far as northern Argentina. When they at last arrive here in spring, the female builds a nest, usually in the understory, lays her eggs and incubates them, while the male sings. But both parents tend the chicks. Hearing the song of that species is certainly a treat for me, but my favorite remains the ruby-crowned kinglet’s cheering carols from the canopy.

Right next to the trail we found a very large scat of a carnivore, full of fur and bones, artistically arranged. A wolf (or possibly a bear) had dined well, probably on marmot.

On this hike, some of the wild flowers were appearing—lots of buttercups, some chocolate lilies and miner’s lettuce, three kinds of violets, a few enchanter’s nightshade. Occasional salmonberry canes bore flowers, but there were wide stands of dead canes, some of which showed no evidence (?yet) of new canes coming up at the bases of the old ones. Does that bode ill for salmonberry production up here this year?

A special floral sighting was a clump of some kind of saxifrage, growing on boulder. We’d seen this on previous hikes too and noted the leaves with three sharp terminal teeth. That made identification simple—the three-toothed saxifrage. The leaf margins have scattered hairs, a feature that led us astray for a while, but consultation with real botanists eliminated the confusion and confirmed the name. This species is not common in our area, but it seems to be the only saxifrage here with three-toothed leaves. The white petals have reddish spots on them (so does another species, but that one has different leaves). It’s fun to try to figure out such things and learn new species; now if I can just remember all the distinguishing features…

Of course, having the right name is just a small part of any story! Many questions lie in wait for curious naturalists. What insects pollinate this plant? What is the function of the spots on the petals? Do the marginal hairs on the leaf deter some herbivores? Does this plant typically grow on rocks? And so on. That’s where the real interest and fun lie!

Just for fun of a different sort, on a completely different topic: I put up a peanut butter feeder on my deck this spring. A simple thing, it consists of a small block of wood with pits (for peanut butter) drilled into both sides of it. This dangles on a hook where I can see it easily, while lazing in my big comfortable chair. The chickadees found it almost immediately and visit it regularly. Did they know that this funny-looking thing might have food or are they just curious? Once there, one experimental peck would tell them there were goodies to be had, worth coming back for. For several weeks, I saw only chickadees there. Then the juncos began to come. Maybe they saw that the chickadees were making repeat visits and decided to check it out. They are considerably larger and much less acrobatic than chickadees, but they somewhat clumsily began to perch on top and reach down to the peanut-butter-laden holes. As time went on, they became more adept and more skillful at extracting several nice bites before losing their balance and fluttering down. Clearly they were learning how to exploit a new resource!

Occasionally other birds came too; a hairy woodpecker clung to the side of the feeder and reached quite easily over to the food source. A Steller’s jay sat on the deck railing, scoped out the situation, and flew straight at one of the gobs of peanut butter, snatching out a good mouthful on its way back to the railing. That worked, so it repeated the maneuver a couple of times. But it has not been seen again.