Twisted pines and many questions

Strolling on snowshoes around the Lower Loop at Eaglecrest one gray, damp day, we found, as expected, that conditions forreading animal tracks were bad on the rain-packed snow. So we counted trees instead: we had noticed previously that some of the dead or dying pines in the meadows had very twisted trunks, mostly with an upward twist to the right. So this time, we counted the pines with right or left twists and also checked whatever dead hemlocks or spruces we encountered. This informal, unscientific survey produced a series of questions, largely unanswered.

As a curious naturalist, I find it great fun to generate focused questions, even if I can’t answer them. This essay is an example of how the process goes.

–Is there something particularly about pines that produces the markedly twisted trunks? The other conifers in the Juneau areaoccasionally show such marked twists (but seemingly fewer in proportion to the total population of those species) and we have the impression from other observations elsewhere that deciduous tree trunks don’t generally twist like these pines do.

–If the twists occur predominantly in pines (that casual observation should be verified, of course), perhaps there are intrinsic factors, such as differences in the cells that make the wood, that predispose pines to twist. The principal wood cells of conifers do differ from those of deciduous trees, but do pinesdiffer from other conifers? Or perhaps there are environmental factors, such as exposure to wind and snow, that contribute to twisting? We would need to find a good sample of pines that grew in more protected circumstances to examine that possibility.

–We noted that most of the twisted pines have right-twists. Along one section of the Lower Loop, Righties outnumbered Lefties more than fifty to one. However, a casual check along the CBJ Crow Hill trail found very few twisted pines and there were proportionately more Lefties there.

So now the questions can be asked: Is the predominance of Righties due to some factor of genetics (or very early development)? Is there some environmental difference between the two locations that contributes to the very different frequencies of different twists? Or is it an accident of genetics and who happened to colonize Crow Hill vs the Lower Loop?

–As luck would have it, on the return loop, we spotted a long-dead tree, probably a pine, that had broken off near the base,exposing a central core of straight-grained wood surrounded by many layers of twisted wood. Something apparently had changed as the tree grew—the older growth rings made straight wood but the later growth rings made twist. But what?

It can be frustrating to generate lots of questions for which we have no ready answers, but it is good fun to think about the complexities! Attentiveness to things around us as we walk andthinking about the things we observe adds richness to our strolls.

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Three winter surprises

Regular bird-watchers spotted an unusual bird in Auke Bay this winter—an American coot. Although range maps show occasional migrants in southern Yukon, at the present time the Auke Bay record is the most northern, according to ebird. Coots are members of the rail family, which includes the sora that is often found in the Pioneer Marsh in summer. Most coots breed farther south of here, but there are isolated breeding populations in east-central Alaska and southern Yukon; this individual is presumably doing its winter things and may migrate north later.

American coot (cleaning up the harbor?) Photo by Kerry Howard

Although they sometimes use salt or brackish water on migration, coots typically nest in freshwater marshes with fairly deep water and lots of tall vegetation. They eat mostly aquatic vegetation, but also take small animals, both invertebrates and vertebrates, at times. Food is gathered by dipping the head underwater or by diving, and usually brought to the surface for swallowing. They sometimes feed on carrion, or steal from ducks, or even snatch flies out of the air. They are strong swimmers; they don’t have fully webbed feet but they have toes with lobes on the sides that increase the size of the foot paddle. 

Coots are strongly territorial, vigorously defending a nesting territory again other coots, as well as ducks, grebes, and sometimes other birds. They are socially monogamous, but in some populations there seem to be floater females that lack a mate and a territory and these females sometimes dump their eggs in the nest of a mated pair. Nests are placed on floating platforms of vegetation, often anchored on the sides by tall cattails and reeds. Multiple platforms are built by each pair and used for courtship, and one is used for the nest. The nest itself is made of small bits of vegetation, making a smooth basket big enough to hold the eggs, although this tends to get trampled flat by the time chicks are present. The floating platform tends to sink, so the parents have to continually repair and augment the structure.

A normal clutch size is about eight to twelve eggs per nest; larger clutches are probably due to the activities of egg-dumpers.However, most of the dumped eggs do not produce chicks, because the nest-owners usually reject the excess eggs. Both parents incubate the eggs, the males mostly at night. Incubation takes a little over three weeks, and the eggs hatch over a span of about three days. Chicks can hop out of the nest and swim around just a few hours after hatching, calling loudly for food to be delivered. Long ago, when I was doing my thesis research in the marshes of eastern Washington, I was fascinated by the goofy appearance of those little chicks, as they swam around after the parents. They have thick black down feathers with stiff, curly, orange tips, a nearly bald head, with some bluish patchesabove the eyes, that’s fringed with red or orange frizzy feathers, and a mostly red bill. It turns out that the oddball coloring is important in stimulating the parents to deliver food. Young birds are chased out of the parent’s territory after about three months, to live on their own and mature at age one year.

Also appearing this winter is another critter that is rare around here: Fishers live in northern forests across North America, but only recently (since the mid 1990s) have they been recorded in Alaska and southern Yukon. These pioneers are thought to arrive via the Taku River valley. Fishers belong to the weasel family (Mustelidae), smaller than wolverines but larger than marten. They climb well, because (like squirrels) they can rotate their hind feet so the toes point back; they are active year-round. Like other members of this family, they are fierce predators, capturing mostly rodents, hares, and grouse, but also eating carrion, insects, and fruit—but not usually fish, despite their name. Fishers are very good at killing porcupines, biting the face and then flipping them over to rip open the belly. They also sometimes prey on marten and weasels, and research has shown that these smaller mustelids tend to avoid times of peak foraging by fishers.

Fisher. Trailcam photo courtesy Riley Woodford

Although males and females mature at age one year, most successful breeding starts at age two. Dens for mothers and kits are usually in cavities in big logs and trees. Kits are generally born in early spring, and females come into estrus and mate a few days later. Sperm meets eggs and a fertilized zygote is formed, but it does not develop very much right away; instead, it just rests in the uterus until late winter, when it is implanted in the uterine wall and active development begins. Litter size is commonly two or three kits, weighing less than two ounces each, which depend on mother’s milk for at least three months and may be weaned at four months. By early fall, they are about full grown; males usually weigh about twice as much as females.

Trailcam photo courtesy Jos Bakker

One more little surprise: a trail cam in the Dredge Lakes area has recorded significant beaver activity in the middle of winter, despite heaps of snow and some very low temperatures. Small trees have been chopped down and hauled away, presumably for food. We seldom see winter activity like this around here. Adult beavers typically live on stored fat reserves while remaining in the lodge in winter. However, kits keep growing through the winter months, and they need to eat. They usually feed on a cache of sticks in front of the lodge, but maybe this family didn’t make a big enough cache.

Toxic birds and bugs

Thousands of insect species have chemical protection against predators or parasites. These chemical compounds are often derived from plants (which made them for their own defense); for instance, herbivorous larvae sequester these compounds, so they and the ensuing adults are protected. Enemies may be deterred from attack by the smell or learn from experience to avoid insects that produce nausea or other unpleasant effects. Chemical protection provides clear advantages to survival and reproduction. A well-known example is provided by monarch butterflies: The larvae eat milkweed plants, taking in toxic cardiac glycosides; birds that try to eat the larvae (or the later adults) get sick and quickly learn to avoid such prey.

A less well-known and fascinating example is the colorful bella or rattlebox moth, whose larvae feed on poisonous seeds of a legume, storing the toxic alkaloids in their bodies. Predatory orb-weaving spiders and wolf spiders reject toxin-laden larvae and adults. Female moths transmit the toxins to their eggs. Male moths transmit the toxins along with sperm during copulation, and females mate many times, building up their supplies of the toxins. Thus, the females and their offspring gain better defenses. Males advertise their supply of the toxins (with an airborne pheromone) and females favor males with bigger protective chemical gifts to offer, somehow even giving precedence to their sperm over those of others. 

In contrast to the insects, very few birds are known to be toxic (at least to humans or other mammals). The European common quail (a subspecies of a widespread species) sometimes makes some human consumers ill, but only in fall when the birds are migrating south, possibly because of some seasonal food in the diet; other subspecies living in other regions are not usually considered to be toxic.

Bronze-wing pigeons in Australia attracted notice when introduced mammals (cats, foxes) died after eating them. The pigeons eat seeds, including those of a particular legume that contains toxins. I found no reports, however, of effects of pigeon-eating on native Australian animals (did they not eat pigeons, or were there no observations, or did they tolerate the toxins?).

The largely herbivorous spur-wing goose of Africa sometimes has poison in its body, perhaps from eating blister beetles, which contain the potent toxins cantharidin. These birds could be self-medicating by occasional beetle-eating, perhaps reducing intestinal worms and microbes. A contrast is seen with the great bustard of Eurasia, which is thought to self-medicate in this way, at least in some populations, although this bird is not reported to have toxic effects. As an interesting aside: In the mating season, male bustards eat more beetles than females, perhaps cleaning out their guts to demonstrate to females (which inspect the males’ rear ends) no diarrhea and a clean bill of health.

North American ruffed grouse sometimes made human consumers sick, but effects varied among individuals and were chiefly restricted to later winter and the eastern part of the North America in the 1800s and 1900s. These effects may have been due to winter diets that included mountain laurel, a species known to be toxic to sheep and whose honey is toxic to many consumers, even bees.

A small songbird called the red warbler, living in parts of Mexico, was long-ago reported to be unpalatable to humans; more recently certain toxic alkaloids have been identified from the feathers.

In all of these cases, the toxic effects are regional, seasonal, orvariable among consumers. It seems unlikely that the responsible compounds evolved because of their occasional effects on the particular consumers/predators; they might have some metabolic function, for example. In short, these toxic effects maybe incidental, from the point of view of the bird–they may not have evolved because of a protective function, in contrast to insects, and they may have some other function that provided an advantage that led to their evolution.

There are, however, a few known instances of direct deterrence or protection by avian toxins. Hoopoes in the Old World produce very smelly material from the uropygial (‘preen’) gland near the tail. Females spread this stuff over their feathers and their chicks, and the chicks produce it too. It is said to contain certain bacteria that destroy other bacteria that would damage the feathers.

The best-known cases of toxic birds are some species of pitohui and the ifrita of New Guinea. Touching these birds’ feathers and skin leads to tingling and numbing in humans (a fact well-known to the local natives), so eventually researchers discovered that the feathers are coated with material that contains alkaloids called batrachotoxins—highly potent poisons similar to those of the famous poison-arrow frogs. These birds may get the toxins from eating certain beetles, probably storing them in the skin and spreading them while preening the feathers; the toxins are also found in muscle tissues. There is evidence that the toxins reduce populations of ectoparasites such as lice and ticks, as well as various predators such as snakes, raptors, arboreal marsupial mammals, and humans. Levels of the toxins vary among species and among regions.

The subject of avian toxins is little-studied, so far. Many other birds are reported to be unpalatable or noxious in one way or another, and it seems likely that careful research may turn up more cases of both incidental and evolved chemical protection.

Surf, bird food, PSP

Surf’s up! In early January, high winds stirred the waters of Juneau, making boating an unpleasant if not downright dangerous proposition. The waves pounded the coastlines, roiling the waters next to the shores. Even moderate wave action at the shoreline is sometimes a good thing for hungry birds—the turbulence seems to wash out small invertebrates into open water where ducks can gobble them up, one little item at a time (https://vimeo.com/662110696). It also may loosen cobbles and gravels, making hidden invertebrates accessible to gulls and shorebirds that pick and probe (https://www.naturebob.com/gulls-taking-advantage-surf). Splashes and wetting might encourage upper intertidal mussels relax their tightly closed valves a bit, making it easier for oystercatchers to insert their long, thin bill and extract the soft parts. We see the birds doing these things, but I don’t know that anyone has actually measured the effects of wave action on the inverts…Maybe the birds know more than we do.

Black oystercatcher eating blue mussels. Photo by Bob Armstrong

The oystercatcher feeding on open mussels in the video was filmed in Tee Harbor in spring of 2019, at a time when the level of PSP in the mussels was already high and getting higher. Paralytic Shellfish Poisoning is caused by neurotoxins produced by microscopic algae that feeding molluscs filter from the sea water; certain algal species are especially known for their neurotoxins. The term is earned for the unpleasant and sometimes devastating effects on humans that ingest clams and mussels containing the toxins (and other animals that ate such molluscs). Also, I’ve read that heavy surf can break up the bodies of small planktonic and shoreline organisms, allowing the wind to carry body fragments and neurotoxins as aerosols. By impeding the transmission of nerve impulses, these toxins affect respiration, muscle contraction, and other essential functions. Micro-algae also produce other toxins, which affect digestive systems, memory, and other aspects of consumers.

What about non-human consumers, including the molluscs themselves? Some molluscs just stop feeding when exposed to toxic algae; others are sensitive to the toxins and suffer some negative physiological effects. But some develop resistance to the toxic effects when they are repeatedly exposed to the toxinsand accumulate them in their bodies, in some cases retaining the toxins for many months, passing them on to other consumers. When crabs eat molluscs, they can build up toxins in parts of their bodies too. So sea otters, which eat both molluscs and crabs, may suffer some of the negative consequences; but they can learn to reject prey with high levels of the toxins. Predatory snails (whelks) that feed on mussels and clams ingest the toxins too. And when small fishes (anchovies, sand lance, young salmonids, etc.) and crustaceans feed on the toxic algae in the plankton, and then become prey to other predators, the toxins can pass up the food chain, becoming more concentrated at each step. All around the world, massive die-offs of marine fish (e.g., sardines), mammals (e.g., whales, dolphins, sea lions, seals), and birds (e.g., cormorants, pelicans) have been attributed at least in part to PSP, wreaking havoc in marine communities. 

All those reactions and interactions begin with the neurotoxins in the algae. The toxins are produced all the time by the algae, but the reactions we notice happen more often when there are ‘blooms’ of algae; the blooms result from strong inputs of nutrients (such as nitrogen, iron, and phosphorous) stemming from spring run-off, outflow from melting glaciers, and drifting volcanic ash, which carry minerals dissolved and eroded from rocks and fields. Tides and ocean currents redistribute the nutrients along the coast. Those nutrients allow the algae to reproduce prodigiously, so they are then a super-abundant food source, readily available to consumers.

And that leaves the question of why the algae make those (and several other types of toxins) in the first place. How and why did all those varied compounds arise? So far, I have not found agood answer to that. However, I thought of three kinds of answers: 1) perhaps the compounds contribute to some essential metabolic process or they are produced just as a byproduct in the course of some metabolic, physiological processes that have some effect on growth or reproduction—the toxicity to other organisms is just incidental (from the point of view of the algae).In other words, their function is simply related to the internal workings of the algae. 2) The toxic compounds serve as a defense again would-be consumers, presumably small, planktonic critters (such as copepods) that would feel the direct effects of the toxins and be deterred from eating the algae. There is experimental evidence for this in some cases. In general, the advantage of deterrent or protective effects would be expected in the first level of consumers (the primary consumers); any indirect effects and consequences for secondary consumers higher in the food chain would probably be ‘collateral damage’–irrelevant to algal fitness and the evolution of the compounds. 3) Both #1 and #2 could happen. In other systems, researchers have found that something that arose for one function eventually evolved another function. Given the wide array of micro-algae involved and the variety of compounds that are toxic to many animals, it would not be surprising if all three kinds of answers turn out to be valid. Scientists have a big job ahead of them, to sort out all of this.

A hearty thanks to four fine folks at the NOAA lab who responded so promptly and helpfully to my queries.

Strolling on the snow

The deep snows this winter are too much for these little snowshoes we usually use here—one just postholes, and the enlarged feet have a hard time pulling up out of the hole. The old North Woods style of ‘shoe would be more suitable. But the little ‘shoes are what we have, so we tend to stick to the groomed trails, walking on the side of the trail as much as possible and avoiding disturbance of the classic tracks set by the groomer.

One day in late December, a friend and I strolled up Montana Creek, looking for signs of wildlife activity. But nary a track could be seen. Strange. Some distance up the trail, a bit of open water appeared, just a very narrow, intermittent channel. Friend wished for a dipper—and just on cue, one came around a curve, flitting downstream. It stopped briefly in each small opening in the ice but didn’t seem to find much to eat and eventually went farther downstream. But there wouldn’t be any open water there until it reached the Mendenhall River, so its explorations would have to continue. When streams are frozen, dippers often forage in intertidal zones.

The next week, we rambled around the Lower Loop at Eaglecrest, where critter-tracking is often rewarding. This day was no exception: there were weasel and porcupine trackways ranging widely; voles and shrews had scampered in and out of sheltered spots. Snowshoe hares had explored many places, usually under brush or low-hanging conifer branches, where the snow was not so deep.

There was not much sign of squirrel activity, just a few tramplings near some trees. I wonder if they were using tunnel systems under the deep snow—the squirrel that lives near my house seems to have long, well-used tunnels, which it often uses instead of traveling on the surface, popping up near what used to be a garden. I know that voles and shrews often scurry about below the snow, but they had appeared on the surface fairly commonly. So why not the squirrels– perhaps they weresnacking on things in their snow-buried middens??

Ptarmigan or grouse left their bipedal trackways, often in and around brushy thickets; they may have nibbled blueberry buds as they walked. One of these birds came up to a steep little bank on the edge of the trail and slid on its bum down the loose snow, to find its feet again at the bottom of the short slope.

I spent quite a lot of time in a spot where tracks were overlapping and complicated to sort out. Some were from hares, some from ptarmigan/grouse, but there were others also. Only a few of these others were clear enough to allow possible ID: maybe about an inch and a half wide, with five toes, one of them set back a little from the others.  Hmmm, quite possibly a marten! There was, however, no evidence of predation, so I can’t finish the story.

One critter that commonly leaves tracks near the Loop was missing from the records in the snow on this day: Deer tracks were conspicuous for their absence.

I was interested to see that the lower-most extension of the Loop, near the opening of the Treadwell Ditch trail, showed almost no sign of wildlife activity (just one vole track). I’d noticed this lack on other excursions up there. I have to wonder why so little activity is recorded there—the habitat is the same (to human eyes), so why is this part of the Loop apparently so un-used?

In early January, we walked up the Dan Moller trail, using the convenient snow-machine route, which was packed enough to walk without ‘shoes. Up through the meadows, looking for critter signs, but with little luck. The deep snow transformed the once-familiar landscape into unrecognizable terrain. A little imagination added to the fun; the heavy snows had laden the trees and stumps into wonderful shapes. One that caught my eye immediately was clearly an old woman, draped in her shawl, stooped over while mourning a dead companion at her feet.  Another was a small spruce whose top bore such a load of well-packed snow that it was bent into a full-curl ram’s horn. 

There’s no end to what you might find, if you go stravaiging around on our trails!

Birds underwater

Many kinds of bird regularly forage for prey underwater. These birds have a variety of ways of doing so and adaptations to match. Life in the water is very different from life in the air.

The first hurdle to overcome is simply getting there. Some species start from the water surface. A few are able to just sink below the surface by decreasing their buoyancy: small grebes and anhingas do this by compressing the plumage (thus pushing air out) and exhaling. Others tuck their heads and kick with their webbed or lobed feet (e.g., mergansers, goldeneyes, buffleheads, most cormorants, loons, and some grebes) or flip their wings (murres, long-tailed ducks, dippers). Those that surface-dive a lot (e.g., loons) typically have legs set well back on the body, making them awkward on land. 

Another way to get underwater is from above the surface.Dippers often dive into a stream from a rock or low-hanging branches not far from the water surface. Kingfishers may plungefrom several meters above the surface, folding the wings closer to the sides. Brown pelicans can dive from a height of twenty meters, extending the neck and angling the wings back, making a more streamlined shape. The grand champion divers may be seabirds called gannets and boobies; they can start a dive from almost a hundred meters up, turning the body into a sleek dart, with the neck well-extended and the wings held back close to the body. The dives can reach a speed of sixty mph; to protect the bird from the resulting high impact, the skull is reinforced and subcutaneous air sacs on the chest and sides cushion the jolt.(https://vimeo.com/319325491. By Bob Armstrong, in Loreto, Mexico.)

Belted kingfisher diving and rising with fish. Photo by Bob Armstrong

Most of these dives are quite shallow, but some species are adapted for deeper ventures, with heavier, stronger bones than other birds, to resist water pressure and decrease floatation. Gannets are quite deep divers, sometimes going on down to twenty meters. Loons may dive as deep as seventy-five meters and some of the murres and their relatives go down over a hundred meters; the common murre is said to be the deepest diver (sometimes down to 180 meters) in Alaska. Penguins often launch from ice-ledges; small ones make fairly shallow dives, but the emperor penguin can dive down more than five hundred meters!

The second hurdle to underwater foraging is locomotion in a medium that is denser than air. Most aquatic birds have webbed feet, often set far back on the body for good propulsion and steering; grebes have broadly lobed toes instead. But fancy feet are not always sufficient—some of these birds use their wings to swim in pursuit of prey. Gannets and cormorants can wing-it underwater; murres and puffins have narrow, stiff wings adapted to underwater ‘flight’ (without forsaking aerial flight); penguins swim with their flipper-like wings (and cannot fly) and steer with their webbed feet (some of them are very fast swimmers, clocked at over twenty mph).

Murre underwater. Photo by Bob Armstrong

Kingfishers and dippers don’t have webbed feet, so they have their own ways of moving in water. Kingfishers seem to rise buoyantly to the surface after a dive, wing-fluttering as they lift back into the air. Dippers have strong toes for clinging to rocks and walking even in fast currents, and they swim with their wings for short distances in pursuit of prey; they are the only songbird known to do so and do not have the same adaptions of bones and wings as other, more aquatic, birds do.

Plumages of birds that forage underwater are generally dense and well-waterproofed with oils from the preen gland. Penguinplumage has unusually many tiny filaments that hold air bubbles; when the bird swims, the bubbles are released, which decreases the density of water around the body, allowing faster swimming. Birds that decrease buoyancy by compressing the feathers might get a little of this effect, but penguin plumage can hold more bubbles and release them more gradually.

Diving birds hold their breath underwater, storing oxygen in their lungs. But they can also store extra oxygen in their muscles, in a compound called myoglobin–which, like hemoglobin, is a specialized protein with iron-containing compounds that hold oxygen. Species that engage in long dives and underwater pursuits have more myoglobin than those that spend shorter times without access to air. Emperor penguins can stay underwater for twelve minutes or more (for comparison, humans can normally manage to hold breath for less than two minutes).

Fall Colors

Photo by Mary Willson

Here in a rainforest, we don’t get the flamboyant displays of golden-leaved aspens or the flame-colored maples, although there may be some isolated cases of such brilliance dotted about our city streets. Our alpine zones are sometimes full of glorious color, but not all of us can get there. But we do love color. However, think not that we are deprived of these season visions; we have plenty of fall colors. They’re usually somewhat more subtle and on a smaller scale, but quite wonderful in their own way, when we bother to look. Attentiveness, as Robin Wall Kimmerer noted, is the key to seeing.

Here are a few examples of enjoyable displays of fall colors we’ve seen recently:

–on a hummock in a muskeg, a mat of sphagnum moss had turned partly red, still spangled with spots of gold and green. The mat was decorated with crimson leaves of cloudberry, a cluster of scarlet bunchberries, and bunchberry leaves in scarlet and green.

–the last stands of fireweed can be pink or red, or sometimes both of those colors grading into oranges and yellows and remnants of green.

–subalpine slopes are clothed in deer cabbage, offering a mosaic of yellow, golds, russets, and rich browns.

–high-bush cranberry shrubs often sport many colors—the whole bush may bear gorgeous red leaves. On others, each leaf can display every shade of red, orange, and yellow. Sometimes the whole show is high-lighted by those lovely red berries.

–the understory of the dark conifer forest is brightened by the broad, yellow leaves of devils club, even as they become dilapidated.

–cottonwood leaves often turn bronze or gold and flutter nicely in a breeze. How sad that the whole row of shapely young cottonwoods along Vanderbilt Hill Road has been destroyed.

–along one trail, I found a single salmonberry cane with every leaf a color-treat. An occasional leafy stem of goats-beard may be very red in the midst of others that are still green.

–in the forest edges, the heart-shaped leaves of mayflower turn yellow—or sometimes an unusual pattern of white with black lines.

–sometimes a single leaf displays a variety of color 

–and have you ever noticed that the upper sides of silverweed leaves can grade nicely from orange to yellows to tawny browns?

Summer leaves are green, because the cells contain lots of green chlorophyll that does the work of photosynthesis (making sugars). As days shorten and nights grow longer and cooler, chlorophyll gradually breaks down, exposing the yellow carotenoids that have been there all summer (absorbing light energy and transferring it to chlorophyll), concealed by the green. During those shortening days, some photosynthesis continues, but each leaf is gradually disconnected from the rest of the plant, so sugars are poorly transported to the rest of the plant and build up in the leaves. In bright light, they are built into colorful red-to-purple anthocyanins. A single leaf may sometimes be red on one half and yellow on the other, if one half was exposed to sunlight and the other was shaded.

That simplified explanation leaves many questions. Why build anthocyanins in a dying leaf?  Why do some species often produce lots of red leaves in fall, while other usually bear yellow leaves? Why do some of the typically yellow-leaved plants occasionally make red or orange leaves? Why do alder leaves just turn brown, with no bright colors? Readers can probably think of still more questions!

In any case, there is lots of color to enjoy, even in the rain.

Autumn Begins

On yet another gray, wet day, some friends went up the Eaglecrest Road in early September, frequently stepping off the road to make way for big equipment. Some headed for the Nest, while I and some others searched for the rare white-petalled variety of dwarf fireweed (a.k.a. river beauty). Sadly, it was done flowering—as was almost everything else. There were a few laggard monkshoods, yellow rattle-box, and groundsels, and I saw some delayed salmonberries just ripening. Deer cabbage leaves shone with yellows and golds. It was really autumn at Eaglecrest.

White fireweed. Photo by Kerry Howard

I was interested to hear reports of a Clark’s nutcracker in the area, and there were several bird-watchers on the road, hoping to spot it for themselves. This bird is normally found in montane conifer forests from central BC southward, but I’m told it occasionally ranges north to the southern Yukon and is very rarely seen in our coastal conifers.

Marsh felwort. Photo by David Bergeson

Looking back to our so-called summer: a trip to Crow Point and the Boy Scout beach in mid-August found the little gentian called marsh felwort in its usual place near the trail on flat, gravelly soils. Five pointed petals make bluish or lavender stars that usually appear in August. This little annual plant occurs widely in the northern hemisphere. In the spruce groves there were fairy rings of white mushrooms and a clump of giant purple mushrooms known as purple (or violet) corts. Corts belong to a multi-species complex in the genus Cortinarius and form mycorrhizal associations with the roots of spruces and other trees. Also, around one big spruce tree, I saw a palatial squirrel midden with numerous entrances, one of the most impressive middens I’ve even seen. A lot of spruce cones were demolished to make a pile that size.

Photo by Jennifer Shapland

Both brown and black bears frequent these meadows, and I recently saw tracks of both species. We often see bear diggings here. Usually the bears have been digging roots of Angelica lucida (‘seawatch’), occasionally also eating the lower stems and leaf stalks. But this time, there was one area where bears had concentrated on digging up beach lovage; dozens of holes were marked by the discarded reddish leaf stalks. When the roots of these perennial plants are eaten, presumably the population of those species is reduced, thus reducing their future availability as bear food—unless the plants set enough seed before the roots were eaten, and the seeds germinate well, to establish a new generation of those species in the area. Also, a few side shoots and root fragments survived the digs and can regenerate full plants, but would this be enough to replace those eaten?

Another August hike took us—squelching all the way—to Cropley Lake in hopes of finding a blue gentian in flower and the yellow fireweed. Success! Also known as yellow willowherb, it usually grows along damp creek-sides and in montane meadows. It looks very different from the common pink-flowered fireweed, which is now classified in a different genus altogether. We also enjoyed some stands of the deep, rich purple monkshood flowers. There were hundreds of fringed grass of Parnassus flowers; in a previous essay, I related the history of how it may have got its name.

Yellow fireweed. Photo by Anne Sutton

At the very end of August, I went with a friend to the first meadow on the Spaulding trail. All across this meadow, we found many small diggings in the moss, leaving no evidence of who made them or what might have been taken. We found the seed heads of the strange little wetland plant called Scheuchzeria (sometimes called pod-grass). Widespread in the northern hemisphere, it has is currently classified in its own taxonomic family, and I have found very little information about its ecology and behavior.

A brief stop on a log for a snack provided a lucky sight of two chickadees: After conversing with each other in a nearby pine (no doubt about the odd lumps on the log), one by one they came down to a fruiting skunk cabbage. On each visit, the bird plucked one seed off the club-shaped infructescence, leaving a little empty pit, and flew off, but quickly returned. Jays and other critters sample these seeds too, sometimes leaving big bare patches, but it was good to see these little guys in action.

Transplants in Southeast Alaska

Since the 1920s, mammals of fourteen species have been transplanted from one location (mostly but not always in Alaska) to another location in Southeast. Many of the official transplants were done with the hope of establishing viable populations of game species in new places, with the goal of providing more prey for humans. The processes of capturing and transporting the unwilling immigrants commonly resulted in high mortality, even before the animals were deposited in their new sites.

Many of the transplantations failed. An attempt to establish a moose population near the Chickamin River in the 1960s failed altogether; all the transplanted young moose died. At that time, officials declared it was too expensive to do a preliminary habitat assessment and thought it more practical to just dump the moose there and see what happened. A number of other transplant attempts over several decades are said to have failed: deer to the Taiya Valley, goats to Chichagof, mink to Strait Island, muskrats and marmot to Prince of Wales, wolf to Coronation Island, snowshoe hare to Admiralty and other islands. Ill-advised attempts in the 40s and 50s to establish populations of non-native raccoons failed.

Some transplants were successful, apparently without any serious preliminary assessments: the mountain goats now living on Baranof are descendants of the transplants in the 1920s, and marten were moved to Prince of Wales, Baranof, and Chichagof in the 1940s and 1950s. After a habitat assessment in Berners Bay, a number of young moose were deposited there in 1958 and 1960; they established themselves successfully and that local population has grown. It may be emigrants from that area that we observe near Cowee Creek, Herbert River, and the Mendenhall Glacier. The possible effects of moose browsing on the structure of the vegetation in Berners Bay are apparently not known; given the notable cropping of willows and other shrubs in Gustavus, one might wonder about the effects on nesting habitats for birds—especially in the light of research elsewhere documenting that over-browsing can drastically reduce bird habitat.

Elk (a non-native species) were brought to four islands in Southeast in the mid to late 1900s. The elk, from Oregon and Washington, were exchanged for mountain goats from Alaska. Only the 1987 introduction of elk to Etolin Island was successful, and elk eventually dispersed from there to nearby Zarembo and other islands. Some preliminary habitat assessments were made, but post-facto concern about possible competition with existing deer populations arose, so continued monitoring and perhaps management are necessary.

After marten were transplanted to the three big islands, red squirrels were often introduced as prey for marten. It later became clear that marten really prefer voles and it is unlikely that the squirrel transplants had much effect on the introduced marten populations. However, it is very likely that the squirrels are having a negative impact on nesting birds on those islands, because they prey on eggs and nestlings.

Collectively, these attempts to establish new populations of mammals are a very mixed bag. There was a high cost in mortality of animals (not to mention dollar costs of capture and transport), many transplant efforts failed, and there was little attention paid to possible consequences. The impetus for game translocations in Southeast may have abated somewhat, and as our ecological understanding has grown over the years, it seems likely that any further transplants would be done with greater concern not only for the animals themselves but also for proper preliminary assessments and the ecological consequences.

Several additional transplants were done in attempts to augment existing populations or to re-establish a previously resident population. However, the effect of adding new animals to an existing population (deer to Kupreanof in 1979, for example) is usually not known. A transplant effort in 1989 attempted to restore a much-reduced population of mountain goats on Mt Juneau, with the stated intent of improved wildlife viewing (!). All the transported goats initially moved away, but by the early 2000s, goats were again seen on the ridge, although no one seems to know if these animals are related to the transplants or from a natural population on nearby ridges.

Sea otters have been re-introduced to many places in Southeast at various times, to restore the natural population that was extirpated by human activity. These transplants are apparently successful and the population of sea otters in Southeast is growing. The consequences of sea otter presence are currently being studied by faculty and students of UAF.

The historical information in this essay derived from Tom Paul’s 2009 ‘Game Transplants in Alaska”, ADFG Technical Bulletin #4. In addition to the official transplantations, there have been an unknown number of unofficial and mostly unrecorded ones, done by private citizens.

Aquatic plants

Prompted by a discussion with another naturalist, I’ve been thinking about plants that grow in fresh or brackish waters and their unsung importance to animals. So this essay is about aquatic plants (collectively called macrophytes) such as pond lilies (Nuphar), milfoil (Myriophyllum), burreed (Sparganium) , buckbean (Menyanthes), pondweed (Potomogeton), water crowfoot (Ranunculus), ditch grass (Ruppia), arrowhead (Sagittaria), and some sedges (Carex) that play many ecological roles relative to animals. Therefore they also have numerous ramifying effects on many aspects of local ecosystems. Here are some examples.

Northern Milfoil. Photo by Bob Armstrong

These aquatic plants are eaten by animals. For example, Canada geese nibble the shoots of Lyngbye sedge out on the wetlands; later in the season they grub up the root, leaving characteristic divots. Sedge stands closer to the forest edge are grazed by bears, deer, and sometimes moose. Moose forage on buckbean and other aquatics (see this video by Bob Armstrong), which are reportedly very digestible forage plants and a good source of minerals. Geese, swans, and ducks graze on the leaves of milfoil, ditchgrass, burreed, ditch grass and other species too. Geese and ducks eat the seeds of sedge, milfoil, burreed, ditchgrass , and other species, in some cases passing undigested seeds through the digestive tract and thus dispersing the seeds. All of those animals are, at some point in their lives, potential prey for various predators.

Swans feeding on milfoil. Photo by Bob Armstrong

Beavers (and humans and muskrats) dig up and eat the nutritious tubers of arrowhead; beavers also eat the yellow pond lilies, buckbean, and soft leaves of several species. Beavers are habitat engineers, creating pond habitat for nesting birds and juvenile salmon. They are prey for carnivores such as wolves; a recent report concludes that wolves are able to plan ahead to set up ambushes for beavers, as well as just running them down on land.

Some of these macrophytes (e.g., water crowfoot, buckbean, arrowhead, pond lilies) produce flowers that are pollinated by insects. The visiting insects may obtain nectar or pollen as food, and they are prey for several kinds of birds.

Damselflies have evolved an unusual use for these plants: female damselflies insert their eggs in the leaves and stems of various aquatic plants, sometimes submerging themselves for several minutes. The emerging larvae are predators on other insects and are themselves (as both larvae and adults) prey for other insects, fish, birds, and frogs.

Macrophytes provide protective cover for small fish, such as sticklebacks and salmon fry, which in turn are prey for larger fish, birds (such as kingfishers and mergansers), otter, and mink. Similarly, toad tadpoles and some aquatic insects hang out in the watery ‘forests’ of pondweed or milfoil, temporarily hiding from predatory insects, fish, or birds.

In addition to providing food, cover, and egg-laying sites, the standing ‘forests’ of aquatic plants provide a handy substrate for dense coatings of algae. Photosynthesis of the algae produces oxygen that improves the breathability of the water. The algae are eaten by toad tadpoles and by herbivorous invertebrates such as snails, which in turn are prey for fish and birds.

These ecological connections are relevant to local ponds (such as Twin Lakes) that are sometimes managed to reduce the density of milfoil and other macrophytes. The species of milfoil in those ponds has been identified as a native species (northern milfoil, Myriophyllum sibiricum). A study of this species (and the invasive Eurasian milfoil, M. spicatum) in eastern North America showed that the native species generally supported more snails and other invertebrates than the invasive species. Those rich communities of invertebrates provide food for fish and waterfowl. Some of the waterfowl also graze directly on milfoil. Thus it becomes important to understand the ecological effects of reducing milfoil density in the lakes. How is the foraging of fish and birds changed? Also, perhaps reducing the density of the native milfoil facilitates invasion by the Eurasian species (widespread in North America and it might be in our area too), which supports poorer invertebrate communities. Furthermore, the invader can hybridize with the native species, changing its palatability or digestibility along with the associated composition of the algal community, with resultant effects on the animals that use milfoil. Hmmm, a potential research project awaiting attention…