End of summer

low water, autumn flowers, mountain fish, and alder eaters

It’s really fall, now—the autumnal equinox has passed, and we’ve all noted the rapidly shortening days. The fireweed leaves are mostly reddish and the seed pods have shed their offspring to the winds. A friend observed that the curly valves of the pods looked like the plants had been given perms—all by the same hairdresser.

Late summer, and the long drought reduced my home pond to little more than a mud puddle. Even so, two broods of mallards visit every day, no doubt drawn by the seed spilled from the feeder that hangs over the erstwhile pond. The young ones are well-feathered and nearly as big as their mothers. The hordes of pine siskins that monopolize the feeder are very messy and lots of seeds fall down where the ducks gobble them up. The two duck families don’t mix at all and typically push each other around.

There weren’t many fish in the pond earlier in the season—just a few juvenile salmon and some sticklebacks. They probably weren’t doing very well in the shallow, warm, and turbid water. I watched a mallard grab a young salmon from the shore and walk off with it before gulping it down. Fish-eating by mallards is not as odd as it might seem: when I worked at the hooligan run in Berners Bay, I often saw ducks eating dead or moribund hooligan.

Late summer, and at low elevations the fireweed is finished blooming. Purple asters are now on show in many places. In some of the meadows near Eagle River there have been nice displays of long-blooming grass-of-Parnassus and—a special treat—some lovely stands of felwort with its small, blue, star-shaped flowers, just starting to bloom. Felwort always seems to bloom late in the summer, when most other flowers are done. It’s something I look forward to.

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Felwort. Photo by David Bergeson

All summer long, I’ve had a pot full of the little pansies called johnny jump-ups near my door. One day in July, I came out that door and said “I’ve been robbed!” The two deer that mutilated the fireweed in the front yard, nibbling the upper leaves down to ragged stumps, had come round and mowed down my little johnnies to a height of about three inches. No flowers left. Well, I nursed those plants back to something like their sprightly selves and they again flowered briskly. But the deer came back and this time they left only one-inch stubs. After some considerable time for recuperation, now the johnnies are trying again, but there are many few flowers this time.

One August day I watched a young buck demolishing more fireweed in front of the house. He slowly wandered along the edge of the drying pond where I have some poorly tended terraces. As I watched, he started chomping on the Canterbury bells. That was just too much. I eased my way slowly toward him and when he finally noticed me (he being much too busy eating!), he went the other way, with determined sedateness and his dignity intact, and so disappeared into the woods. But I reckon the deer are not done with my flowers!

Up at Cropley Lake the fish were rising. These are resident Dolly Varden that mature at a small size, much smaller than the sea-run dollies. There are also resident dollies in the creek that flows from the lake, but I’ve been told that the population in the lake is probably quite separate from the one in the creek, with little or no genetic mixing. The lake population is thought to have been there a long time.

In mid-August, on North Douglas, I happened to notice an alder shrub whose leaves had been reduced to skeletons. Some critter had eaten the blades and left just the veins. A closer look found some of the perpetrators—a cluster of fuzzy white caterpillars. These turned out to be woolly alder sawfly larvae. Later, driving out the road, I noticed other alder stands that were nearly leafless.

In consultation with the helpful FSL entomologist, Liz Graham, I learned that there are at least three kinds of sawflies working on alder leaves. The striped alder sawfly is a native species. The woolly alder sawfly and the green alder sawfly are not native here, although the woolly one seems to be naturalized and the green one has been in this area for several years. Heavy sawfly infestations are patchily distributed, nothing like the widespread swaths of browned hemlocks, whose previous-years’ needles are being decimated by the hemlock sawfly this summer.

Sawflies are not true flies; they are related to bees and wasps. They get the first part of their common name from the long, serrated tube through which females deposit their eggs. I’ve read that the three species deposit eggs in somewhat different parts of the leaf: woolly ones on the underside of the leaf and in the midrib, green ones on the upper leaf surface, and striped ones along the leaf petiole. The eggs take one or two weeks to hatch. The green alder sawfly burrows into bark and wood when it is ready to pupate, but the other two species pupate in the soil; the adults emerge the following year. It takes more than one year of defoliation to kill an alder, but defoliation by the insects means that there is less nitrogen from decaying leaves put into the soil. The nitrogen-fixing bacteria that live in alder roots put lots of nitrogen into the plant, and this gets recycled back to the soil when the leaves decay. I wonder about possible ecological consequences of breaking that nitrogen-recycling pattern.

Three little stories

Otters on the ice, fish at an upwelling, and an unusual feeder visitor

Here are three small stories, two from the field and one from home, two that were simply fun and one that leaves some questions.

One day in early February, I put on snowshoes with the intention of poking around in some meadows out the road. There was not a lot of snow, but the ‘shoes sometimes make it easier to walk over snow-covered grassy humps and bumps. And off I went, seeing a few tracks of mink, shrew, mouse, and weasel. A porcupine had wandered from the meadow down to the ice-covered creek and up the other side. Its trail intersected another trail, made by a river otter that had come upstream on the ice. In fact, there were two and possibly three otters, weaving in and out over the ice and finally coming up the bank. They went over a short stretch of meadow, under some trees, and down to a tiny, frozen slough. I decided to follow this trail as it went along the slough. The frozen channel got gradually wider, but I found one place where the ice was broken, perhaps by the otters. The edge of the opening was packed flat by otter feet, so it was clear that they had spent some time by this hole in the ice. What could they have found there? The trail continued down the icy slough, eventually joining the main creek again where there was some open water and a good chance of finding small fish. The total journey from creek-leaving to creek-joining was maybe half a mile. I think that these hunters knew where they were going and were just checking out another part of their home range.

I was having so much fun that I didn’t pay attention to my feet. When I finally happened to look down at my feet, I was surprised to see that I’d thrown a ‘shoe. So I back-tracked to retrieve that lost one, almost all the way back to where I’d picked up the otters’ trail. Having fun seems to be distracting!

One day in the middle of February, I wandered out into the Dredge lakes area, following a tip from a friend. After threading my way through a noisy passel of school kids, I went straight to one corner of Moose Lake. This is where we often see migrating trumpeter swans in fall, but this time I was looking for some patches of open water. I found them, under some snow-laden alder branches. The surface of the water was roiling periodically, so I knew something was going on in there. Peering closely into the dark water, I saw them: several big Dolly Varden moving slowly about in the shallows. I could pick out the white borders of their pectoral and pelvic fins, which are a good field mark. There was another big fish in the same bit of open water, a fish with no white on the fins and black speckles all over the body…probably a cutthroat trout. Dollies and cutthroats are known to overwinter in Mendenhall Lake and some of the accessible ponds in this area, where they hang out but feed little in the cold water. Why would they be in this spot? This area also sometimes hosts spawning coho in fall, so there is something special about it—and that’s the upwellings, where ground water burbles up through the sediments, bringing oxygen with it. Those fish are probably there to take advantage of the oxygenated water, which can be in short supply in some of these small ponds. As I watched, a dipper zipped out from just under the snowy bank and disappeared under the arching branches.

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Dolly Varden. Photo by Bob Armstrong

On the way back to the trailhead, I started to duck under some low-hanging alder branches and saw something flit to the side. So I quickly looked up and saw a redpoll, perched not eighteen inches from my face. On the branch I had ducked under was a cluster of alder cones, a favorite food of redpolls. This bird scolded me roundly, so I apologized and moved on, while the bird went straight back to ‘his’ cones. I only saw one redpoll just then, but shortly later and not far away, I saw a whole flock of them at the seed feeders on my deck, cleaning up the millet seeds. Redpolls seem to show up around here sometime in February, most every year, making me wonder what they were doing in the earlier part of winter.

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Common redpoll on alder cones. Photo by Bob Armstrong

My suet feeder at home normally attracts chickadees and juncos. But sometime in January I noticed other visitors. There were two very small birds that spent several minutes clinging to the wire-mesh suet holder and pecking at the suet. I was astonished to see that these were golden-crowned kinglets, birds that customarily feed on dormant bugs and spider eggs among the conifer needles. This was not a ‘one-off’ visit; they returned several times over the next few weeks (maybe more often than I noticed, given that I don’t spend the whole day watching from my windows).

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Photo by Mark Schwann

This observation seems so unusual to me that I asked one of Juneau’s ace birders about it. I was told that, indeed, golden-crowned kinglets had occasionally visited their suet feeder too. Further inquiry via the internet revealed that this feeding behavior by golden-crowned kinglets has been reported, but very rarely, in Michigan and Tennessee, for instance.

Golden-crowned kinglets are so small (about six grams) that they lose heat rapidly (having a high surface-to-volume ratio), but they can’t store much fat. So they have to eat a lot each day, moving continuously through the foliage in search of tiny, sparse prey. They may save some energy at night by lowering their metabolism a bit and by huddling up together in sheltered spots, but the risk of going hungry and perhaps starving is significant. Given the high demand for energy, why don’t they visit suet feeders more often? And what got these few birds started on suet-feeding in the first place?

Around Cropley Lake

“Elysian fields” of Eaglecrest

Ambling up from Eaglecrest to Cropley Lake at the end of July, we passed from summer back into spring. Near the lodge, the tall blueberries were ripe, attracting batteries of pickers with buckets. Just a few hundred feet higher, the low-growing bog blueberries sported their tightly closed pink buds. By the lake, flowers were still blooming while at the lower elevations, the same species had set seed. The tiny white gentian, however, dotted the meadows almost everywhere.

We found several stands of the pretty shrub called copperbush. It’s related to blueberries, but you wouldn’t know it from appearances. The flowers look entirely different: they have spreading, coppery petals instead of the pendant, pinkish-white bells of the blueberries, and the fruit is a dry capsule, not a succulent berry.

I don’t know how long Cropley Lake has been there; a small pond may have occupied the bowl originally. One drainage was blocked by a dike, decades ago, judging by the size of the spruce trees on its crest. A dam was built across another drainage, and the overflow from the dam feeds a small pool, which drains down-valley to help create Fish Creek.

We sat on the boulders just below the dam, watching the miniature Dolly Varden foraging on surface insects. They ranged in size from four to eight inches or so. Many of them had colorful orange fins, and we guessed that these were males. They could be mature individuals, despite their diminutive size.

The resident Dolly Varden in Cropley lake were undoubtedly introduced by humans many years ago. Resident Dolly Varden, which live their whole lives in fresh water, mature at a small size. A tiny female may produce only a few dozen eggs. If some of their offspring get washed downstream to the sea, they may survive and adopt an anadromous life style: growing to a large body size and re-entering fresh water to spawn. But return to Cropley Lake can’t happen; there is at least one barrier falls.

The dollies we saw in the pond below the dam may be in for a hard time, come winter. The pond must often freeze right down to the bottom, or nearly so. In past springs, I’ve sometimes seen several dead dollies here, with no living individuals in sight.

On the other side of Cropley Lake, we found a stand of creamy-flowered plants growing near a seep. They looked rather like fireweed, except for the flowers. I think I once knew them, but–as with so many things—the knowledge had faded. However, our handy plant guide told us that they are indeed yellow fireweed, more of a habitat specialist than our common pink species.

I was pleased to find numerous butterwort plants, a.k.a. bog violet. The purple flower is vaguely violet-like, but the nectar spur at the back of the flower is much longer and the face of the flower is distinguishable upon close inspection. Butterworts are insectivorous plants; their flat yellowish leaves are sticky traps for insects, which are then digested by the plant. The insects are a good source of nitrogen for plants growing in boggy, nutrient-poor soils.

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Butterwort. Photo by Bob Armstrong

We also inspected the stems of the little iris relative with the ponderous name of sticky false asphodel. The flower stem is covered with sticky hairs that trap miniscule insects. Some years ago, we did experiments to see if this plant could be insectivorous, putting chemically labeled fruit flies on the sticky stem and then testing for presence of the label in the plant’s seeds and roots. No luck. There may be another function of the sticky hairs that remains to be discovered.

For those interested in the names of things: the true asphodel is an Old World lily (not an iris) and it was the flower of the Elysian Fields in Homer’s Odyssey. These fields were the meadows where dwelt the souls of the dead. (The name ‘asphodel’ was also strangely corrupted into ‘daffodil’, a totally different plant.) The famous Parisian avenue called Champs Élysées means Elysian Fields, presumably referring to the gardens that once flanked it and not to a collection of dead souls!

An early autumn

Leaves and flowers, fish, mammals, and birds in transition

Fall came to Juneau in mid August. Cottonwood trees began dropping yellow leaves and alder leaves browned and shriveled. The air felt different, and it smelled different, too. On fine, sunny days, clouds of fireweed seeds, floating on their white parachutes, filled the air and collected in windrows on the shores. Mushrooms appeared all over the forest, as if from nowhere.

The grasses and sedges in the coastal meadows slowly changed from green to yellow and gold. Although the splendid pink flowers of fireweed were gone, the stems, leaves, and pods still filled fields with pink and red.

At mid elevations, a few fireweed stalks still bore flowers and some had, in fact, just started to bloom. But the deer cabbage leaves already showed yellow and orange and russet. As the rains increased, the once-fluffy heads of cottongrass drooped dismally, like small mop-heads. But there seems to be a bumper crop of highbush cranberries, glowing brilliant, translucent red (slightly less ‘bumper’ now, after my visit…).

Flocks of robins scoured the roadsides for grubs and worms. In Sheep Creek valley, robins, varied thrushes, and whole families of fox sparrows foraged on elderberries. Near Steep Creek, dozens of warblers flitted from bush to bush. Most were yellow-rumped warblers in immature plumage, but the flocks included several ruby-crowned kinglets and occasional Townsend’s warblers and orange-crowned warblers. I was interested to observe the reactions of the crowds of visitors who waited, mostly impatiently, for a bear to appear. Almost none appeared to notice the many warblers that flew back and forth across the creek and gleaned bugs from the shrubs.

If the bears were occupied elsewhere, many folks enjoyed watching porcupines—studies in slow motion. There were several small ones (known as porcupettes), born last spring, that frequented the Steep Creek area. They were now largely independent of their mothers, foraging on their own and growing perceptibly from week to week. Sometimes one would spend several days in a single cottonwood, taking long naps in between sessions of shredding and skeletonized the leaves. We watched one chomping on willow leaves for a while and then wandering to the creekside, where it avidly consumed dwarf fireweed and then drank from the creek.

The sockeye run in Steep Creek dwindled dramatically during the last two weeks of August. The few remaining pairs of salmon were attended by lots of Dolly Varden, which eagerly line up behind a spawning pair. Dollies, young coho, and sculpin all love to gobble up loose salmon eggs.

Foraging bears left partly eaten salmon carcasses on the streambanks, and it wasn’t long before the flies found them. Soon some carcasses were squirming with hundreds, maybe thousands, of fly larvae (maggots). I was initially surprised to see a bear lick up a pile of maggots and then show one of her cubs the tasty little morsels remaining from her snack. On second thought, however, there should have been no surprise, because bears eat grubs and ants and bee larva when they can. But this was the first time I observed bears eating maggots instead of salmon.

A family of well-grown mallards, still accompanied by mama, foraged regularly in the creek. They scarfed up unburied salmon eggs, enjoyed a snack of maggots on old carcasses, and enthusiastically ate fresh salmon meat when a bear abandoned its catch.