Autumn is here in earnest

the subtle fruits of a somber season

We pass the autumn equinox, and the days get ever shorter. They’ve been getting shorter ever since late June, but now we really begin to feel it. The fall rains are here, and when we look out our windows, we see gray gray gray. It’s seldom as bad as it might look, however, so it pays to get out and about.

In fact, I think that getting outdoors is an important part of living with short days and gray skies. Some folks flee the fall and winter by going south, but I have found several ways to enjoy staying here during those seasons. I try to get outdoors every day, talking a walk on one of our trails; maybe not a long walk, but I’m out in the fresh air, seeing something besides four walls. I sometimes play a game with myself: the challenge is to find at least one thing (preferably three things!) of esthetic or natural-history interest. Sometimes these things are connected: I like to recall the visiting musician who took a walk in the forest and found that the rich variety of green tones in the mosses and ferns reminded him of a piece he had just played; now every time he plays that piece, he’ll see the rainforest. I greatly enjoy the rich cultural life in town, especially the music; the visual and thespian arts are also alive and well, and various lecture series can be both instructive and entertaining. Also, I do best when I have a project or two to work on; it doesn’t much matter if it is writing or building bird houses—a project that engages what’s left of my aging mind.

When I’m out, there are actually several autumn things to look forward to. Great rafts of scoters gather in the coves and channels. It is fun to watch them do what I call ‘chain diving’—a whole line of scoters dives, one after the other, in the same spot; then they all come up, one at a time, a little farther away. I have not yet found anyone who can tell me exactly what they are doing or what food they might be finding or why they do it in that way.

Out on sandy, gravelly bars, there might be small flocks of shorebirds that spend the winter with us. Rock sandpipers and dunlins often hang out together. Adults in breeding plumage of both species have black belly patches, and some show the black blotches as winter goes on, so look closely to distinguish them. These shorebirds breed on the Arctic tundra of western and northern Alaska. Sometimes there are surfbirds on rocky reefs and points; they nest in alpine tundra of Alaska and the Yukon. I occasionally flush a solitary snipe, not only in the marshes and swamps where they might have nested but even along streams in the forest.

I look forward to spotting the first slate-colored juncos that arrive at the bird feeders; they come from the Interior to spend the winter with us. Oregon juncos live here all year but mix with the slatey ones in winter. At present, both kinds of juncos are classified as the same species but different subspecies or races.

Thinking about Oregon juncos reminds me to ask a question: these birds are distinguished from slate-colored juncos in part by a chestnut-brown back. Likewise, our chickadees have chestnut-backs that are lacking in the other North American chickadees. Is there a particular reason why chestnut backs are popular here? Is there something about rain forests that favors that plumage pigmentation?

Of course, the black-billed magpies come to us in the fall too. They temporarily monopolize bird feeders, tease the eagles, and sample leftover salmon carcasses. On a rare sunny day, the iridescence of their black feathers makes them quite spectacular.

Flowering season is over in fall, but you might spot a few late purple asters alongside the trail. Behind the Visitor Center at the glacier, there has been a very late blooming Romanzoffia sitchensis (the common name is Sitka mist-maiden). In the muskegs, look for tiny yellowish cups that might be mistaken for flowers. These are the seed heads of the swamp gentian. Each two-parted cup holds a little cluster of seeds; when a rain drop hits the cup, the seeds get splashed out and so dispersed. This ‘splash-cup’ dispersal is not common, but it is shared by the bird’s nest fungus.

Sept-11-Dan-Moller-11-Gentian-seed-pods-resize
Gentian seed pods

One of my favorite things to do is watch the coho arrive in local creeks. When they do, the bears—which have been waiting for them, ever since the sockeye run ended—get busy again in the streams, and that makes for great bear-watching. I think that many of our local bears really depend on coho to ‘top-up’ their fat deposits in preparation for hibernation. The amount of fat laid down in fall is important in determining how many cubs a female bear can feed while they are in the winter den and it is probably important for winter survival of juvenile, subordinate bears that are not yet expert foragers.

I don’t know all the factors that regulate the size of coho runs, but there is evidence that juvenile rearing habitat is one important factor that helps determine the size of a local coho population. Incoming adult salmon are commonly able to slither over or jump over most beaver dams, so dams seldom limit the spawners. However, juvenile coho rear in pools in streams and in beaver ponds, and research has shown that they grow really well in beaver ponds. Down in the Pacific Northwest, biologists have even re-introduced beavers to certain stream systems, so that their ponds will increase the available rearing habitat for salmon and help restore the diminished populations. Because salmon typically return to their natal stream when it is time to spawn, juvenile rearing success helps determine the size of the spawning run. Thus, when beaver dams are removed from streams where coho spawn (so that their ponds are drained), or when beavers are trapped out of a system and their dams (and ponds) are no longer maintained, and rearing habitat is thus reduced, there is reason to expect that the coho population of that stream will decrease. And that leads to the expectation that the bears living in the area would lay down less fat, possibly survive less well, and produce smaller litters of cubs.

To John Muir Cabin

late flowers and early arrivals

By sheer luck, a late October ramble on the Auke Nu trail to the John Muir cabin found us in partial sunshine. Some of the boardwalk was even rather dry, although most of it was still very wet and slippery. All the usual mudholes were still there, of course, and we can only hope that someday they will be filled with gravel. A major erosion channel is developing along the trail near the trailhead and a large spruce has tipped up its roots, exposing its very shallow root system.

A few dwarf dogwood and bog laurel flowers stubbornly persisted, but they waited in vain for a passing bee or fly to do the pollinating. Blueberries still hung on the bushes—we just don’t get enough migrating thrushes and wandering bears or other critters to clean out the berry crops and accomplish all the potential dispersal of seeds, especially in a year of bumper berry crops like this one.

The John Muir cabin has been nicely renovated. New floor, new table, new bunks upstairs and down, and a nifty spiral staircase to the loft. A door at the top of the stairs helps control heat distribution, and an escape hatch, with ladder, provides an emergency exit from the loft. New windows offer great vistas and ventilation if needed. There are lots of pegs for wet rain gear and grab bars for swinging into the upper bunk.

The wood stove now sits in the middle of the floor, with space around it for folks to move about. The propane heater works well. And there’s a brand new outhouse, complete with gravel walkway from the cabin. Pretty cushy!

October is the mating season for porcupines. The babies of last spring are still very small, but they are now on their own, chowing down on the remaining herbage before shifting to a winter diet of bark. So their mothers are ready to mate again. If you hear strange calls coming from up in the tree canopy, and you are pretty sure it’s not an unusually inventive raven, it might be a male porcupine announcing his availability to nearby females or perhaps a couple of males squabbling over mating privileges.

Winter arrivals from the Interior have been here since September. Slate-colored juncos now mix with our local Oregon juncos at feeders. Black-billed magpies call raucously, visit seed feeders, and are constantly on the lookout for something better. They are good scavengers, and salmon carcasses are high on the list of favorites. Just recently, I saw an eagle perched on a rock in the Mendenhall River with a dead coho at its feet. Hanging around, just out of the eagle’s reach, was a hopeful magpie, waiting to dart in for a morsel or two. No doubt there were a few more magpies lurking nearby.

Postscript on the Bear Creek Dam in Douglas:

Some weeks ago, I wrote about the early history of this dam. Here are some tidbits about later history there. The CBJ water department tells me the dam was decommissioned in 1985, when Douglas went onto the city water system. No one currently at the water department knew about early maintenance activities at the dam, but some Douglas residents remember that CBJ occasionally cleaned the walls of the reservoir when water was low. At low water, residents could hike up the canyon above the concrete dam and find an old log dam, presumably left from the abortive attempts to mine that area. When the reservoir was full, this was a popular spot for picnics and swimming in summer, and for skating in winter. Between the dam and 5th Street is an old viewing platform, reportedly sponsored by Gastineau School for access to the creek and class projects.

The dam is reported to be structurally sound still, and the CBJ water department goes up there once a month to make sure the tailrace is clear of obstruction, so water flows freely through the bottom of the dam.