Lawson meadows

wet-snow tracks and tiny treasures

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The meadows near Lawson Creek are a favorite destination for a Parks and Rec hike or just for exploring. You can now get there from the snowmobilers’ parking lot on Blueberry Hill, up to the Treadwell Ditch, then south on the Ditch Trail and over the new bridge at Lawson Creek. The upstream loop of the old Ditch Trail is now cut off by the new bridge, but you can go partway up the valley on the old Ditch Trail after crossing the bridge or hop right up into a chain of meadows that stretches up the valley.

Or you can start on Crow Hill, go up the CBJ trail to the Ditch and then, instead of going left on the Ditch Trail to Gastineau Meadows, go right. Rather than using the Ditch Trail here, I prefer to go up the little slope into the first big meadow. From there, you just continue around the slope and head up Lawson Valley through the chain of meadows.

Eventually, you run out of meadows and the forest takes over. Parks and Rec usually turns around at that point, has lunch, and heads back down. On a recent excursion, our lunchtime ‘café’ was sheltered from the rain by some tall, dense conifers, and we looked out our ‘window’ at the last meadow.

The snow was heavy and wet, and the skiers in the group found it fast going, making it back to the cars in record time. The snowshoers took a good bit longer. On this wet day, the muskegs on the CBJ trail were overflowing the trail in some places, creating deep slush but no problems for our passage. (Right now, as I write, it is hard to even think about rain and wet, what with low temperatures and howling winds that lift the snow into swirling clouds hundreds of feet tall. The mountain peaks are invisible.)

There were deer tracks in the lower meadows. The deer were sinking in pretty deeply and probably found it hard to move from one relatively snow-free, forested area to another. In winter, deer find their food under the trees, where the snow pack is less than in the open. There were also several sets of snowshoe hare tracks, partially covered by a little recent snow. Best of all was a set of porcupine tracks, small and close together, showing where a young one, now independent of its mother, had wandered around snacking on shrubs.

Two other wintry walks yielded a couple of tiny treasures that I’ll share:

Before the rains, during an earlier the deep-freeze, I found lots of silken threads dangling from branches. The silks were probably left by juvenile spiders, which use these threads to become airborne on a passing breeze. That’s how they disperse away from their mothers to begin their independent lives. On that day, each silk was covered with layers of tiny crystals of hoarfrost, which sparkled like holiday tinsel—only better!

The second little treasure, at the edge of the Mendenhall wetlands, was short-lived. I heard an unusual bird song nearby and soon spotted a magpie under some alders. The bird was fossicking about, occasionally pecking at the ground, and singing a very soft, sweet, delightful little song, all to itself. It sang for several minutes, and gradually went out of sight and hearing in the alder thicket. The bird seemed happy; I certainly was!

Eating lichens

feeding a diverse group of animals… including humans

Walking along the East Glacier trail one day, I noticed a scattering of gray lichen scraps on the snow next to a small tree trunk whose lichens were the source of the scraps. Some small creature had ripped off much of the lichen, leaving the bits on the snow. A narrow groove led away from the lichens to a small burrow that led down under the snow blanket. That made me think a shrew had been rooting around in the folds of the lichen for insects or spiders, but it was also possible that a small vole had been selectively feeding on the lichen itself.

A few days later, on the Spaulding Meadow trail, I was following some deer tracks, to see where they were going, when my more observant companion called my attention to where the tracks had come from.

There, not far from the trail, there was a noticeable browse line in the arboreal lichens (witches’ hair or Alectoria) hanging from the tree branches, and underneath there was a multitude of deer tracks. All the Alectoria lichens below a certain height, within reach of a foraging deer, were missing from that patch, although they could be found not far away where the deer had not walked.

These observations made me think about lichens as a food source for animals, and I have a very helpful local lichenologist to thank for some great references (as well as instruction on lichen identification). Some lichens are not very tasty, some are actually very poisonous, many have defensive chemicals to deter consumers, and yet a great many critters eat them, often quite selectively.

Somewhere in the world, lichens are eaten by certain snails and slugs, as well as certain kinds of mites and moth larvae; some of these consumers actually specialize on particular kinds of lichen. Although lichen-eating invertebrates have not been well studied in Alaska, we do have a local snail or slug that grazes on the outer layers of leafy lichens. (Recall that a lichen is a composite of a fungus and an alga or bacterium—and some lichens have all three components). Occasionally, if you look closely at the leafy lichens, you might see tiny white trails on the greenish or brownish lichen surface. These meandering trails reveal the white fungal layer below the outer layer, showing where a snail or slug has scraped off the nutritious outer layer that includes the algae or bacteria that also make food for the lichen.

We know a bit more about vertebrates that probably or actually do eat lichens in Alaska.

Caribou are surely the most well-known consumers of lichen all across the North. They use their hooves to dig craters in the snow so they can reach terrestrial lichens, particularly the shrubby, branching ones such as Cladina (reindeer lichens), Cetraria (Iceland lichens), and Stereocaulon (foam lichens), or leafy ones such as Peltigera (pelt lichens). Where there are trees and arboreal lichens, Alectoria (mentioned above) and Bryoria (horsehair lichens) are favorites. Caribou eat lichens all year long, but especially in fall and winter; in spring and summer they consume more willows and herbaceous plants. Apparently, their digestive enzymes change with the seasons, becoming better able to deal with lichens in winter. But lichens are mostly carbohydrate, with low values of protein, so caribou have to find some other source of protein or a means of coping with low levels of nitrogen.

reindeer-lichen-Pam
Reindeer lichen. Photo by Pam Bergeson

Some reports indicate that each caribou has to consume ten or twelve pounds of lichen per day, so a whole herd can make big inroads into lichen populations. Intensive caribou grazing can wipe out whole communities of such lichens, leaving only the low-growing or crust-like ones, and it can take decades for the lichen community to be restored. The most famous example concerns the introductions of reindeer (Eurasian caribou) to St Paul Island in the early 1900s. From just a few animals, the population grew by leaps and bounds, and they ate up virtually all the edible lichens, so their population crashed dramatically. They truly ate themselves out of house and home.

 

In Southeast, Sitka black-tailed deer eat arboreal lichens, as we observed, and so do moose. When mountain goats descend from the peaks into the forest in the winter, they eat arboreal and leafy lichens; in the alpine zone in summer, they may eat branching, terrestrial lichens.

 

There are several species of red-backed voles in western North America and two of them are known to eat both arboreal lichens and branching, terrestrial ones; I found no reports specifically for the species that occurs in Southeast, but it is likely that this species does also. Flying squirrels are important consumers of arboreal lichens (as well as using them to build nests).

 

All these lichen-eating animals are important parts of the ecosystems of Southeast, so it is useful it is useful to consider a few of the ecological interactions that ramify from this lichen base. Some lichens accumulate certain organic pollutants, which are then passed on up the food chain to caribou and deer, and thence to predators such as wolves and humans, where the pollutants become concentrated. Industrial pollution and extensive logging can devastate lichen communities, drastically decreasing the food supply for all of the many consumers. Loss of this important food supply has repercussions in many directions: for example, flying squirrels and voles also eat truffles and disperse the spores when they defecate; truffles are mycorrhizal, making nutrient exchanges with the roots of many trees and supporting healthy tree growth. Caribou, moose, and deer help support predator populations (predators that also prey on other species such as hares and salmon); the browsing of these herbivores can alter plant communities and affect the reproduction of shrubs such as willows and blueberries, which in turn affects bumblebees (that feed on willow and blueberry flowers and go on to pollinate many other kinds of flowers) and birds and bears (that eat blueberries and disperse the seeds).

 

Humans, too, have made extensive use of lichens as food. Indigenous people of the North ate partially digested lichen from caribou stomachs; this material was mixed with fish eggs to make what was considered to be a delicacy (presumably an acquired taste?). In some parts of the world, lichens have been fed to domestic animals, including pigs, dogs, sheep, and cattle, and humans themselves have used lichens as flavoring, thickener for soups, and emergency food.

 

Historically, the biblical manna from heaven, which is said to have sustained the migrating Hebrews in the desert, could have been one of the so-called vagrant lichens, which grow loosely on the ground and can be blown hither and yon by a wind. Many things have been called ‘manna’, including plant resins, honeydew from scale insects and aphids, and certain mushrooms, but vagrant lichens seem especially plausible as the biblical manna, because they would take up water (and expand) after a rain or morning dew, and they can accumulate in some density after a wind (and dew, rain, and wind are all mentioned in one biblical account or another, in association with the appearance of manna). Lichen-manna is quite edible (to humans, camels, and sheep in the Old World, as well as pronghorns in the Idaho high desert) and can be made into bread, but some reports say that it should be eaten in small quantities.

Although lichens seldom claim much of our attention, it should be clear from these considerations that they should not be neglected!

Benjamin and North Islands, part 2 of 2

profitable prowlings

One of the special treats of our little excursion to Benjamin and North islands was finding ourselves comfortable in shirtsleeves—no jacket needed, even when crawling out of our tents at six in the morning. How often is it that warm in Juneau!?

In addition to enjoying the marine wildlife, we wandered around on both islands, just exploring. We saw one young deer, with a beautiful summer coat of red, and lots of deer sign. Deer had cropped the leaves of false lily of the valley, occasional stems of twisted stalk, and most of the leaves from sapling crabapple trees. A little stand of skunk cabbage had been reduced to ragged nubbins. Fresh water seems to be in short supply, particularly on North Island, so we wondered how deer would get enough water.

We also found skeletal evidence of four long-dead deer, some apparently quite young, leading us to speculate about hard winters in these sites. Two lower jaw bones caused us to query ADFG when we returned. One of the mandibles we found had four cheek (grinding) teeth in place plus a fifth one just erupting at the back of the jaw. A mature deer lower jaw holds six cheek teeth (three premolars and three molars), and the full set is in place at an age of about two and a half years. The jaw with the just-erupting fifth cheek tooth had belonged to a young deer, perhaps nine to twelve months old, according to ADFG.

The ground, in some places, was riddled with small holes, just the right size for a red squirrel, but we saw no evidence of current squirrel activity: No busy little fussbudgets chattering at us, no middens of stripped spruce cones, and many of the holes had spider webs across the opening. This year, there are huge numbers of spruce cones still on the trees, so food supply for squirrels should be quite decent. We wondered, then, if there had been squirrels here in the past, but perhaps a year or two of poor cone crops had wiped them out.

Among the rocks on the uplifted beach meadows we startled several good-sized voles, which scooted quickly into handy crevices. How did they get to these islands? They can certainly swim well, but it’s a long distance, for a vole, from the mainland to the islands.

As we stood quietly in a beach meadow with a dense population of lupines, we heard tiny tapping sounds and soon discovered the source: Mature lupine pods were explosively twisting open in the hot sun and the dispersing seeds clattered softly down through the surrounding vegetation. At the upper beach fringe, a stand of cow parsnip presented heads of closely packed clusters of maturing seeds. We were fascinated to observe that each little cluster of seeds resembled a rose, carved in wood. So the whole head was, so to speak, a bouquet of wooden roses. Beautiful!

Some very sturdy, squat plants lined the top of one beach, and bore yellow daisy-like blooms. These beach grounsels, with large, spreading leaves, are very specific to this particular habitat type. Each yellow ‘flower’ is really an inflorescence composed of a ring of showy flowers around a disc of many, small, not-showy flowers, altogether forming the daisy-like composite inflorescence. We noticed that ants were visiting the central flowers, presumably sipping nectar. What an odd place to find ants, which don’t seem to be common in Southeast.

On the forest floor were numerous evidences of predation: Three piles of crow feathers (and feet), plus a regurgitated pellet with an intact crow foot. Four piles of gull feathers. Scattered plates of chitons. Sea urchin tests (a.k.a. shells). Some clam shells and small crab legs. Eagles and otters, and perhaps others, had found their dinners.

Other sightings:

  • A row of extremely contorted spruces on a raised terrace well inside the present forest edge. What could be their history?
  • A dogwood bush, normally shrub-sized, but in this instance sending a long branch or two far up along a spruce trunk, almost like a vine. Apparently its only chance to reach the light was to straggle upward, because the dense thicket of young spruce at the forest edge effectively blocked light from shrub-level.
  • An orchid with vanishingly small flowers (with the regrettable name of adder’s mouth), presumably pollinated by insects as tiny as no-see-ums. Could those miserable pests actually have a use?
  • Several specimens of slime mold, growing on fallen logs. One kind was white and spongy, the other was yellow and fuzzy-looking. Spending most of their lives as separate cells in the forest floor, upon some unknown signal the cells come together to form the visible mold, and reproduce.
  • A family of Pacific/winter wrens in a heap of wind-thrown trees, the young ones curious, the parents wary.

From our perspective, our prowlings were profitable. These little explorations are like treasure hunts in which the treasure is unknown ahead of time but recognizable when one sees it.

Advancing spring

returning migrants, early blossoms, and more

Ever so slowly, spring is creeping up on us. Although my terraced rock ‘gardens’ are still well-buried in snow (but less so, since I shoveled off a foot or two), the ice on my pond is perceptibly thinner. The seemingly endless sunny days (in Juneau?!?) are helping, but the night-time temperatures, at least at my house, are still freezing. The ice on Mendenhall Lake is quite thick—in the middle, but near the edge it is not reliable. There was much consternation on a recent Parks and Rec hike, when a new hiker ventured out on the ice and fell in. He swam through crumbling ice to shore, where he was quickly required to shed at least some of his soaked clothes and don borrowed raiment.

Some good things are happening. The hummingbirds are back, hovering around some folks’ feeders. There’s a dearth of flowers with nectar, so they must be eating mostly insects and spiders, plus the sugar syrup in the feeders. I’ve heard red-breasted sapsuckers squealing their nasal call, so they have returned. Robins are back again, too, in flocks on the beaches and, as singletons, clucking and fussing and starting to sing in treetops. Song sparrows are singing in the thickets near the shores. Just after Easter, I saw the first golden-crowned sparrow at my seed feeder, looking chubby but eating as fast as its bill could go.

Recent explorations around Eastertime turned up more signs of progress.

On the big rock peninsula across from the Visitor Center, we found the first purple mountain saxifrage in bloom, with lots more to come. Out near Nugget Falls, crevices in the cliffs held the first green fronds of the rusty cliff fern and parsley fern. Nearby, a single flower of purple mountain saxifrage peeked out of its leafy clump. Elsewhere, skunk cabbage is up, in places, and should soon be swarming with the little brown beetles that come there to mate, and incidentally pollinate the flowers.

The goats around the glacier are still foraging at low elevations, but they seem to be slowly working their way up to their summer grounds. Hooters are sounding off on the hillsides. We are starting to see queen bumblebees zooming around, gathering food for their first brood of larvae. Willow catkins are a good source of pollen for the bees.

A trip to the Boy Scout beach area yielded a broad expanse where geese had grubbed for roots and shoots. There were also some mysterious craters in one area, some of them at least a foot deep. Could they be evidence of early prowlings of a brown bear? That’s a question, because a keen local naturalist has suggested that brown bears may dig deeper holes than black bears, when they’re after roots.

Over on Douglas, the snow was still impressively deep. The Dan Moller cabin was still buried at Eastertime; a very narrow defile led down to the outhouse door. A little meander over some mid-elevation muskegs (on snowshoes) showed us that deer had been regularly moving from one tree well to another. Snow at the tree bases had melted had melted, exposing several feet of actual vegetation-covered ground (several feet down!). We guessed that the deer were foraging on dwarf dogwood and trailing raspberry leaves, and perhaps lichens as well, with snacks of blueberry twigs in between.

Wild crabapple trees grew at the edge of several small muskegs. They provided us with a nice puzzle. The bigger, older trunks had cracked, scaly bark, and almost every one had been visited by some creature that scaled off flakes of bark, exposing the lighter-colored wood or new bark beneath. And most of those light-colored patches were dotted with up to four tiny, conical pits. Our best guess was that a three-toed woodpecker had been foraging, whacking off the bark scales in search of whatever small invertebrates might be hiding there. Indeed, two days later, I saw one of those birds in the same general area, drumming on a dead spruce. But what are those little pits? Could they be marks where a woodpecker’s sharp bill had stabbed at a bug startled by the sudden removal of its bark shelter?

A walk out to Bridget Point involved lots of post-holing and some wading in the little canal that forms on the trail in the lowlands. A woodpecker was drumming, which led to a big discussion about how to tell the drumming patterns of different species apart. It clearly was not a sapsucker, but distinguishing several other species proved to be dicey, even with the aid of helpful programs on convenient hand-held electronics. There were rewards in seeing a northern shrike perched atop a spruce, hearing a pygmy owl calling, and glimpsing a few of the first ruby-crowned kinglets. I didn’t hear them sing, however, until the next day, when spring could then ‘officially’ begin.