A frustrated avian predator

a tale of predators and scavengers

The second week of April began quietly, with a few snow flurries and early-morning new ice on my home pond. The ice was gone by midmorning and on the ninth, the first mallards arrived. Males and females, they swam in the narrow open channel between the ice and the bank or loafed on the ice platform in the center of the pond. And they came every day thereafter.

Seeds on the deck railing attracted the usual juncos, chickadees, and nuthatches. But one day a raven came. It marched the full length of the railing, snapping up seeds of all sizes, one at a time. Reaching the end of the line of seeds, it turned around and did the same in the other direction, until its crop began to bulge. Raven visitations have been extremely rare this winter, and I wonder what prompted this one to come.

One evening, I glanced out my front window and saw a hawk sitting on a dark lump on the pond ice. A juvenile northern goshawk had killed a male mallard, and a few fluffy feathers were strewn about. The hawk had one foot clamped on the duck’s bill, with the other one on the body. As the hawk pecked at the duck’s head, getting small tidbits (the mallard was past caring), it frequently looked all around, as if to check for possible thieves. Then the hawk tore off some body feathers and took a couple of bites, grabbed the duck’s head with one foot and flapped laboriously over to a nearby snowy bank, the prey dangling limply and precariously just above the water surface.The duck probably weighed about as much as the predator, so this was quite a load (although goshawks are known to take prey more than twice their own body mass).

A very damp juvenile goshawk tries to drip-dry on its perch. Photo by Mark Schwann

Once on the bank, the hawk changed its foothold from head to wing, but the prey slid down the steep little bank into the pond and floated immediately under a ledge of snow that stuck out from the bank. Now the hawk had a problem: from the bank above the duck, all it could grab was a wing, while the body was lodged under the ledge. The hawk tried several times to haul the body up over the ledge and onto the bank, taking intermittent rests in nearby trees. By now, it was starting to get dark, and the frustrated, slightly bedraggled hawk took off for a nighttime perch somewhere else. Apparently, the hawk never figured out that if it pulled the wing toward the ice, the body would come out from under the snow ledge and be available. Alas, no photo of all this action was possible without disturbing the process.

Meanwhile, although a squirrel scolded continuously, avian activity on the deck railing continued as usual, with the addition of a face-off between a nuthatch and a junco, which was won by the nuthatch. Ten minutes after the hawk left, other mallards came back to the pond where they’d spent most of the day.

By six-thirty the next morning, there was no sign of the dead mallard in the pond and no new scuffle marks in the snow on the bank. There were muddy footprints, probably of a dog, crossing the ice platform, but at some distance from the place where the duck was last seen. Hmmm, did the hawk come back and figure out what to do or did somebody else appropriate the prey? That all left a frustrated observer too!

Ah, but late that afternoon, I looked out my window again. And there was a river otter, munching away at the carcass on the ice platform, not far from where the hawk had struggled with it. The otter tore big gouts of muscle from the keeled sternum and stripped the long bones bare, mauling the carcass in all directions to expose more edible tissues. By the time the otter went for a cleansing swim, there was just a messy pile of feathers, guts, and bloody bones. None of that disturbed the mallards loafing at the other end of the ice platform!

After the otter swam around the pond (which did scare the loafing ducks) and departed, an eagle arrived. It found a few bitsleft by the otter, gobbled up the intestine, tore the tough gizzard into chunks, and flew off with the bones of the pectoral girdle and parts of two wings in its talons. A raven arrived in the evening, but too late! Only loose feathers and bloody ice were left. And so the duck’s death profited three other critters. A fitting end to the story!

This nesting female goshawk in juvenile plumage attacked the photographer, giving him a good clout on the head with her fists. Photo by Bob Armstrong

Note: The bird I watched was probably a year old (possibly two): its plumage was very dark brown with no sign of transition to adult plumage. Goshawks sometimes start breeding when they are only a year old and still in juvenile plumage, perhaps chiefly in low-density populations where competition for territories is not intense, but tend to have low reproductive success. Some reports indicate that individuals that don’t initiate breeding until age three or four tend to have better nesting success. Foraging experience probably contributes to success at nesting (and having an experienced mate to share chick-feeding duties might help compensate for inexperience in one member of a pair), but many factors, including prey density, prey species, and habitat quality, influence nesting success. Detailed studies are few.

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On tanagers and silverweed

backyard notes, a colorful bird, and a wetland plant

My home pond has been rather quiet lately. Two or three unemployed male mallards loaf around companionably while their females are egg-sitting. Sometimes just one male is there, a female (a late-nester or re-nester) visits briefly, and they forage side by side. But if she comes when two or three males are there already, all companionability disappears and there are serious battles between males. On a sunny (!) day after many days of rain, little fish were rising to the surface; a roving kingfisher swooped down to take one away. Up in the trees, the big treat was seeing a juvenile junco and a juvenile nuthatch, well-feathered, flying, fully competent, but each one still being fed by an attending parent. And out my kitchen window, I saw two really tiny squirrels, frisking about on the tree trunks.

A lucky friend stepped out of her door one day and saw an unusually colorful bird—a male western tanager. The fairly gaudy yellow and black body is topped by a head that’s red or red-orange. I haven’t done a proper analysis but it seems to me that we have fewer really colorful birds than does the eastern deciduous forest, with its grosbeaks, orioles, cardinals, and (yes) tanagers. Western tanagers are not common here. Years ago, my field crew and I were thrilled to find a nest in a thicket at the head of one of the small bays on the west side of Glacier Bay (if I recall correctly).

Photo by Kerry Howard

We live near the northern limit of the western tanager range. They nest all over the mountain west and winter in Mexico and Central America, feeding on insects and fruit. On the nesting ground, they are territorial; both male and female chase away intruders. First-year males can breed but are subordinate to older males, so they don’t get first choices of where to set up a territory. Pairs are socially monogamous; extra-pair activity is little studied. Females build their cup-shaped nests (twiggy on the outside, lined with grass, hair, rootlets, etc.) often on a conifer branch but sometimes in deciduous trees. Males accompany their mates during nest-building and egg-laying, presumably as a guard against possible philanderers. A clutch of three to five eggs is incubated for almost two weeks by the female, who may sometimes be fed by the male. Chicks stay in the nest about eleven days, fed by both parents. Very young chicks are fed mashed up bugs regurgitated by the mother, while the male apparently brings in small whole insects; older chicks get bigger insects. There is usually just one brood per season.

The red, orange, and yellow colors come from carotenoid pigments. This tanager makes its red plumage pigment directly, probably from insects in the diet, in contrast to other North American tanagers, which make their red plumage by converting yellow pigments that are also derived from their food. The intensity of the red on the head varies, perhaps as a result of differences in insects eaten. It is apparently not known if females choose their males in part on the basis of coloration. Many other studies of western tanager life history are reported to be under way, so stay tuned.

Out on the upper tide flats, we commonly see a plant called silverweed. The common name derives from the silky white hairs that cover the underside of the leaves. I found no information on possible functions of those hairs, although it seems possible that they might retard evaporative water loss by protecting the leaf surface. Be that as it may, silvery leaves upturned by the wind made a field of pink shooting stars even more spectacular.

Silverweed flowers are yellow; they may or may not be self-fertile (depending on what source you read). The flower has nectar and is visited by bees, flies, and beetles. It also has stolons or runners that spread out over the ground, and new plants can grow from nodes on the runners.

The Latin name for silverweed is either Potentilla anserina or Argentina anserina—the proper genus is debated. My interest was caught by the diverse explanations for the long-standing species name ‘anserina’. ‘Anser’ means goose in Latin. One suggested reason for relating the plant to geese that the leaves may have reminded someone of a goose’s foot marks. This strikes me as ludicrous, because I see no resemblance whatsoever. Another explanation is that by growing in rock crevices, the plant is safe from grazing geese (graylag geese in Europe). This notion wouldn’t apply here, because the plant grows mainly on flat sediments that offer no protection from geese. The third explanation is that the plant was used (in Europe) to feed geese. This is getting closer to something real—on our upper intertidal meadows, Canada geese regularly dig up and eat the roots. So we find small pits scattered over the flats where goose bills have grubbed up the roots. One final note: near the mouth of Fish Creek, a group of strolling friends found several spots where the ground was littered with dozens of fresh, bright green spruce tips. We had no good way to account for that–a natural phenomenon, maybe wind, or just kid stuff?

Tree sparrows and bluebirds

…a scrapbook of spring bird stories

In the early part of April, there were sometimes two dozen mallards on my mostly-icy home pond. There was one male who was not fully ‘dressed’—while all the other males in the group had long since acquired their glossy green heads, rusty chests, and so on, this one was only part-way into the typical breeding dress. Was he just a very late hatchling last fall, lagging in maturation, or did he have a metabolic deficiency of some sort?

By late April, the mallard mob had dispersed, leaving one pair in charge of the now-ice-free pond. The male was seriously aggressive toward a visiting solo male, defending both his female and, perhaps, the seed-fall from the feeder hanging over the water.

Out at Eagle Beach, a mixed crowd of six species of waterfowl moved offshore, as a gamboling puppy approached along the water line. A scattering of American pipits foraged over the tideflats, readily distinguished from other small, brown songbirds by their characteristic gait—they walk and run, rather than hop. At the edge of a mown grassy area, I found a mixed flock of juncos, both Oregon and slate-colored, and American tree sparrows. They were all scouring the turf for food and flitting hastily to the surrounding brush when startled. I hadn’t seen a tree sparrow for ages, so this was fun.

Tree sparrows nest way up north, on open tundra with scattered shrubs and thickets of willow, birch, or alder. The nest is usually on the ground, and the female incubates the eggs for about twelve days. Nestlings are fed by both parents and stay in the nest only about nine days, then hopping out to follow the adults on foot. Tended by the parents, they begin to fly when they are about two weeks old. Tree sparrows feed on the ground and also by hopping up to grab seeds from the seed-heads of low-growing plants. In season, they also feed in trees, to eat small berries. This species has not been very thoroughly studied, so there are lots of details to discover.

Through much of April, there were reports of migrating mountain bluebirds on their way north, seen now here, now there, and in some other place. I tried several times in several places to find them, but they continued to elude me. Then, the day after finding the tree sparrows, I strolled out toward the Boy Scout beach. In addition to seeing a fox sparrow, two Townsend’s solitaires, some Bonaparte’s gulls, and a flock of snow geese, I encountered two friends who were intently watching a patch of dead cow parsnip stalks and a few little spruces. They had found a male bluebird, which was foraging in classic bluebird style: watching from an elevated perch, just a few meters above the ground, then dropping down to the ground to pick up an insect and flying back up to an observation perch. Later, I spotted a female bluebird in the same area, and she too was foraging in the traditional way. So, at last, I had found them.

Photo by Kerry Howard

Bluebirds have other foraging techniques too. Sometimes they hover a couple of meters above the ground to scan for bugs or occasionally chase bugs in the air. In the non-breeding season, they add seeds and fruits (of many species) to the diet. To augment calcium in the diet, egg-laying females may eat bits of egg shell or snail shell to help build the shells of developing eggs, and nesting females may feed shell bits to the chicks to help develop good bones.

Mountain bluebirds nest primarily in the mountains of Montana, Wyoming, and so forth, but some of them range more widely, coming in small numbers to northern B.C., Yukon, and interior Alaska. They are cavity nesters, loving old woodpecker holes but also nesting in cliff crevices, nest boxes, and sometimes other human structures. They favor habitats with short grass and scattered trees or snags offering nesting cavities. They are reported to arrive early on the nesting ground, probably because suitable cavities are limited in number, so the early arrivals get the best choices.

Male bluebirds are territorial, defending an area around potential nest sites, and females can then choose among them. Nests are built primarily by females, often guarded by their mates against potential predators and intrusions by other males. Females incubate for about two weeks, usually fed by their mates, and they brood the tiny hatchlings. Both parents feed the nestlings, which stay in the nest about three weeks, and the fledglings.

Mountain bluebirds are socially monogamous, meaning that they form pairs but both partners may go philandering–seeking occasional matings outside the pair bond. This arrangement turns out to be rather common among species that were once thought to be strictly monogamous. A bluebird pair bond typically lasts for a season, including replacement nests or second nests, but a pair does not necessarily stay together the following year.

That blue color that we love is not produced by pigments but by the micro-structure of the feather barbs; both UV and blue wavelengths are reflected. Males within a population differ in the amount and reflectance of their plumage. Now things get more intriguing: In two studies, done in two different geographical areas, brighter males were more likely to go philandering, engaging in more extra-pair copulations, than less-brightly colored males. Their brightness was not related to age or body condition. In one of those two studies, the more colorful males sired more of the chicks in their own nests and more extra-pair chicks. In the other study, the more colorful males were also early nesting and achieved more extra-pair copulations, but the paternity of chicks in their own nests was not enhanced, compared to less colorful males nesting later. Thus, in both cases, the payoff for bright coloration was greater numbers of offspring sired, and potentially greater evolutionary fitness, although the size of the payoff differed between the two areas.

Watching young animals

a bear family, ducks at war, a porcupine child, and flocks of young birds

The first part of July gave me some very nice opportunities to observe young critters just learning to make their way in the world.

Above the tram in Bear Valley, we watched a bear family foraging on green herbage. Mama was all business, but the cubs were more interested in playing. The two larger ones wrestled and rolled, boxed and bumped, flattening the vegetation after mama had forged ahead. Cub number three was a little smaller than its siblings but eventually trotted out of the thickets to follow the rest.

The forest at the top of the tram gave us a close-up look at a mixed-species flock of birds. First we saw a nuthatch, then a chickadee and a couple of siskins, and then the trees were full of a family of golden-crowned kinglets, including numerous fledglings. Accompanying this gang were two brown creepers, hitching up the tree trunks and acrobatically working along on the underside of branches. The entire flock foraged in plain sight for at least five minutes. Mixed-species flocks are thought to be advantageous to the participants, especially in keeping multiple eyes on the lookout for predators, but all the fluttering activity may also stir up insect prey.

On my home pond, we’ve had the duck wars. Three female mallards have brought broods of ducklings to forage along the pond margins and rest in the weeds on shore. Three broods, all of different ages, and the female with the oldest ducklings tended to rule the waters. She often chased all the others, sometimes very aggressively. Her ducklings were quite well feathered in mid July, and those of the next oldest brood were just beginning to show real feathers amidst the down. Then calamity struck—I heard a female quacking loudly and persistently, and I looked out to see that her brood had just been reduced from four to three. With the remaining ducklings closely huddled around her, she fussed continually for at least two hours, and I finally went out—to discover a sorry little pile of down under the trees on the far bank. I suspect a goshawk had found its lunch. The female went on fussing for another hour or more before accepting the new reality.

A friend and I were scrambling along the bank of one of the tributaries of Fish Creek one day. As the valley narrowed down to a canyon, we practically stumbled over a female porcupine with her offspring. Mama quickly hid her head under a log, leaving her spiny back bristling in our direction. Baby, on the other hand, fiddled around a few minutes, then clambered over a stick and slowly made its way between two tree roots. There if finally did the right thing (for a porcupine) and wedged its head into the fork between the roots and erected its defensive spines over the only exposed part of its little body. This little guy was a tad slow off the mark: baby porcupines can execute the typical defensive maneuvers almost immediately after birth. And this one had had weeks to practice. We left them in peace, of course.

Another friend and I led a guided hike up Gold Ridge on a nice but rather foggy day. There were some spectacular flower shows, and an assortment of marmots, including a young one just poking its head above the flowers. We also had a treat, in the form of a juvenile golden-crowned sparrow. The juvenile looked nothing like its nearby parent except in general shape; it had no strong black and gold crown stripes, but it did have conspicuous almost-golden spangles all over its back. This observation was special, because we’d never before seen a juvenile so close-up, even though this bird nests up there regularly.

We saw one female sooty grouse, with some wee chicks hidden in the low vegetation, and one rock ptarmigan, which might have been guarding an invisible brood. But both grouse and ptarmigan seem to be much less common on the ridge than they were just a few years ago.

gray-crowned-rosy-finch-feeding-Bob
Gray-crowned rosy finch adult. Photo by Bob Armstrong

On top of Gold Ridge, we hoped to find gray-crowned rosy finches that nest in the cliffs up there. And, in between swirls of fog, there they were. Adults were feeding fledglings at the edge of a remnant snow bank. The fog made it difficult to see plumage colors, and all the birds just looked black, but eventually we could discern some pattern and distinguish parent from chick. The juveniles were plump, active, and fully capable of doing their own foraging, but –in the way of all young songbirds—they wanted their parents to deliver.

The end of August

a cheery end to a dismal month

A rather dismal August finally dripped to a finish. The sodden ground could hold no more water, so the streams were raging torrents and trails were squishy. The lovely long days of summer were just a memory, as day-lengths shortened rapidly. The fall season in Juneau can be pretty gloomy, but instead of pouting and whining (well, mostly instead), I found some cheering things to see.

Out near the glacier, a very late brood of barn swallows lined the edge of their nest with five widely gaping beaks every time a parent bird arrived. Each time, one lucky nestling would get a bug or two from a busy adult; feeding five big chicks took a lot of work. But all five chicks fledged a day later and were lined up on a fence railing, awaiting food deliveries.

On my home pond, there was another late brood, this one of mallards. A female appeared, trailed by two large offspring that were getting their real feathers. All that was left of the babyish down was a small poof on the rump. These two, about half the size of the female, were the remainder of a brood of five or six ducklings, but both of them, with mama, appeared for many days and finally looked just like her in both size and plumage.

The star of the show near the Visitor Center was a young porcupine, recently abandoned by its mother. That’s normal for this time in the porcupine year. Junior could be seen by numerous enchanted visitors, as it steadily gobbled alder leaves right next to the trail. For variety, it nibbled on some cottonwood leaves or climbed up a willow to demolish more leaves. Its right front leg seemed to be sore and was seldom used, but that didn’t deter the little guy from climbing trees and roaming around the area in search of green delicacies.

A whale-watching tour near Shelter Island found several humpbacks, and soon we were surrounded by them. The adults were placidly diving and coasting along, while a calf was showing off. It breached many time, it lunged repeatedly, and it rolled again and again. Its youthful exuberance entertained us well.

Mixed flocks of migrant songbirds flitted through the shrubbery in several places. Yellow-rumped warblers, ruby-crowned kinglets, Wilson’s warblers, and probably others searched for insects in the foliage. A friend watched an orange-crowned warbler probing both ends of a rolled-up cottonwood leaf in hopes of extracting the caterpillar within. Those masters of fast, erratic flight, the dragonflies, were no match for the wily olive-sided flycatchers, which perched in dead treetops and nabbed the big ‘darner’ dragonflies as they hunted small insects over a creek.

Those of us who hang out near Steep Creek and the glacier were pleased to see an old ‘friend’ appear, strolling on the beach (or what beach there was, given the high waters). This was Na Tláa, the Clan Mother, a.k.a. the grandma bear, who is about twenty-three years old and has not had cubs for several years. She was not very plump and, long after other local bears had their new coats, she was still molting; her back was covered with long, bleached-out, reddish fur, while the rest of her showed shiny black new fur. This old bear foraged on this and that in the vegetation, caught a fish and ate it, looked at more fish in the ex-beaver pond, and eventually wandered on down the lakeshore.

High on the list of fun stuff was an encounter on the Perseverance Trail on the very last day of August. Two friends and I were coming down the trail, just below the Horn (where two benches provide a view of Snowslide Gulch). Some distance ahead of us there appeared a large black lump, followed by two smaller black lumps, moving slowly up the trail. Ooooops! What now?! Steep cliff up on our right, steep cliff down on our left, and nowhere to go but back. So we quietly backed up a hundred yards or so to the Horn, intercepted two other down-hikers, and waited. And there they came, mom and two cubs.

I suggested that we all go up on the little rubble slope on the inside of the curve, to allow the bruins plenty of room between us and the railing. Bad idea! Mom took one look at us and turned around, heading back down the trail. But she hesitated and looked back, as if she really wanted to continue upward. So we all scuttled into a corner of the fence behind the benches. Ah! Much better! The family turned back uphill and sauntered past us—Mom completely calm and owning the trail, the kids a bit skittish. So on they marched, right up the trail. There had been clear signs that some bears had used the trail above, bears that had been eating loads of stink currants. Nevertheless, we hoped they’d find a good place to leave the trail, so as not to be bothered by other hikers.

She was presumably a Town Bear, because she had an ear tag. This female bear was very well-behaved, from our perspective. And we had respected her space. A good encounter!

Drama on the home pond

aerial attacks on fuzzy chicks

A great ruckus arose on my pond, one afternoon in early June, while I was leisurely scribbling, comfortable in my big easy chair: agitated high-decibel quacking of mallard. Of course, I leaped out of my chair to see what was happening, just in time to see an eagle swoop up from the pond into a spruce tree, dropping a couple of feathers as it landed.

Quickly, I checked the surface of the pond—a female mallard had been bringing her brood of ten tiny ducklings (not much bigger than my fist) to the pond to forage. There was a special place on the far side of the pond, right next to a tuft of weeds, where she would call them to come and rest under her wings. Having watched this family for a few days, of course they were ‘my’ ducks and I didn’t want them to become an eagle snack.

I immediately counted the little ones—no easy task, because they were scooting all over the pond, in and out of cover. But finally, all were accounted for. Mama mallard went on quacking, about one quack per second, for the next two hours. Upon consideration, I guessed that the eagle’s failed attempt had been on the female herself; a duckling would hardly have made one mouthful.

That eagle sat in the tree for over an hour, all of its attention clearly focused very intently on the duck family. It was not distracted by a bunch of juncos flitting about in the tree or around the seed feeder, or by me going out on the deck. A hummingbird close by its head warranted only a sidelong glance. Twice in that long span of time, the eagle thrust forward its head and started to lift its wings, as if to launch a new attack. But then it settled down again, one foot tucked up under its feathery skirts.

Meanwhile, the little ducklings often ventured out from the shelter of overhanging alders to forage. They were adept at diving and scuttled over the pond surface in all directions. Mama duck managed to call them back periodically, only to have them scoot out again. But she herself seldom went far from those protective alder branches.

After more than an hour, the eagle did some intensive preening and took off, but the female duck went on quacking, loudly and constantly. All the ducklings scattered over the pond, foraging actively, while mama continued to fuss. About thirty-five minutes later, back came the eagle and made another pass. Failed again and went to perch in the spruce tree. This time, however, it was very inattentive, fidgeting and looking all around, and it flew away after about five minutes. Needless to say, during all this activity, I got no writing done at all.

The departure of the eagle was a relief for both me and the female duck, although she went on protesting for another hour. The little ones were, naturally, oblivious of the threat, responding only to the need for food and (sometimes) the instructions of their mother.

Several days later, all the little ducklings were still accounted for. They were bigger now, maybe almost twice as big as before. Mama duck had more trouble fitting them all under her wings when they rested. In addition, on the pond was a solo female, who probably lost her eggs to a predator, but who was assiduously attended by a male that was still nattily dressed in breeding plumage. So perhaps she will have another chance to rear a brood.

This was the first time I’d ever seen an eagle at my pond, in all the twenty-five or more years of watching. There has been the occasional pygmy owl, and several goshawks. All the ‘gos’ were in brown plumage, i.e. not that of an adult male. Some of their attacks were successful. Of course, I have to wonder what predatory events I might have missed, while otherwise occupied.

Another day, another place: the day after the eagle threat, Parks and Rec hikers went to Cowee Meadows. We always go there in June (some of us go twice) to revel in the wildflower show. This is the fantastic meadow where we have, several times, recorded over seventy (!) species of flower in bloom in June. This time, we didn’t count them. Nevertheless, we enjoyed a good showing of lupine and buttercups; shooting stars were still splendid and the wild irises were just starting to open. More will come, later.

Some welcome news is that the state park crews have been working on the muddy, root-y parts of the trail, making it easier and safer for walking. They were at work on this day and we all said a big thank you. Yay, State Parks!

Bird stories

nest-builders, scat-shifters, and spring singers

One day in late April, two friends and I scrambled up a steep stream-side slope to a perch on a cliff below a waterfall. We hoped to locate a nest of American dippers, which have nested in this spot for many years. Although a dipper sat near the pool below the falls, it eventually just flew up over the falls, and we were no wiser about a possible nest location.

However, as we surveyed the pool and falls, another bird was busy, attending to a clump of moss on a spruce branch above us. A male Pacific wren (formerly known as the winter wren) zipped back and forth, carrying twiglets to that mossy clump, which was obviously intended to become a nest. Male wrens commonly build more than one nest, which are inspected by females during the courtship process. When a female selects one of these male-built nests, she adds a little threshold to the entrance, claiming that nest as her own. If a male builds several good nests, he may attract two or even three females who will raise his chicks.

arnie-dipper1
American dipper. Photo by Arnie Hanger

This nest- building male became disturbed at our presence, fidgeting about while peering at us and then finding an elevated perch from which he sang loudly, as if to make sure we knew we were not welcome (songs are how songbirds advertise ownership of their territories). Birds really do not like to be observed when nest-building—egg- and chick-predators such as Steller’s jays are always on the watch for tasty morsels, and the busy activity of a bird carrying nesting material gives away a prospective nest for the jay or other predator to raid.

We go the male’s message and backed away a little. Although he was still nervous, he resumed carrying small twigs and fibers to the growing nest in the ball of moss. Suddenly, the entire bottom of the nest ball fell out! Apparently, the scrawny twigs of the spruce branch weren’t sufficiently substantial to support the structure or all the in-and-out visits of the builder. The wren vanished into the forest.

A couple of weeks later, I returned to this site. Now the tattered remains of the wren’s nest were tipped catty-wompus, barely clinging to the frail spruce twigs. The wren had clearly abandoned this effort and decided to build elsewhere. I could hear him singing, a little deeper into the woods.

On this visit, however, I did see the dippers in action. They were not building in their traditional site in the cliff beside the falls, but under a mid-stream log, instead. These dippers were a bit late in getting started; dippers on some other streams were already incubating clutches of eggs, the incubating females sometimes fed by the male.

In the middle of May, Gold Ridge still had lots of snow, attracting brave or foolhardy skiers up the trail. Ravens were soaring and cavorting, as usual, over the end of the ridge, sometimes peeling away from the group to roll and tumble acrobatically or to chase a passing eagle.

Two ravens perched on a rock outcrop. Both birds picked up something lumpy and white and moved behind another outcrop just uphill. They came back to the first outcrop without the white lumps and picked up two more. They flew downhill a little way, and there they deposited these objects, carefully placing them in nooks and crevices of the rock. Then they flew away.

This time I could see where the white lumps were placed, so of course I went to look. The lumps were the old scats of a wolf and perhaps a bear, all dry and winter-whitened. What in the world did these ravens want with these old scats? Were they playing some kind of game?

Robins and fox sparrows were singing all over the shrubby slopes above the tram. Above the cross, snow still covered much of the ground, and ptarmigan had left the digested remains of their dinners in the places where they had burrowed under the snow in winter. A flock of pipits flew in and began to forage for insects and perhaps a few seeds in the snow-free patches. Pipits look more slender than sparrows and they typically walk and run instead of hop. They sometimes nest high in the alpine tundra on the ridges.

On my home pond, the mallard battles are over. As many as four males hang out amicably, eating seeds that drop from the hanging feeder and sleeping next to each other. No need to fight now; all the females are incubating clutches of fertilized eggs. This is a big contrast to early-season relationships, when each male fiercely defended his female from the attentions of other males. That doesn’t always work, by the way—the interlopers are sometimes successful. Meanwhile, up on Gold Creek, a pair of harlequin ducks was consorting and foraging. She will nest up there somewhere, and when the clutch of eggs is complete, she will incubate them and he will go back out to sea to lollygag with his chums on some rocky point. That’s the way of it, with ducks!

Early October

gray, rainy days, some expected seasonal changes, and a few little surprises

The mallards on my home pond gradually molted into their breeding plumage, so I could now distinguish males from females, in most cases. Some males were already in good feather for breeding, while others lagged behind, sometimes way behind. So some of those brown ducks were just getting a few green feathers on top of their heads, and it would be a while before they caught up with the rest of the males.

Most of the cottonwoods were nearly leafless (and I would soon have to clean my rain gutters), although the alders were still leafy. A little stroll through Eaglecrest meadows gave us not only some tasty alpine blueberries but a few floral surprises: we found a single blooming bunchberry flower amid thousands of others bearing ripe fruits. One late-blooming pink bog laurel flower stood out against a background of mostly green. There was even a lonely shooting star, which commonly blooms in spring. These solitary flowers had gotten their hormonal signals crossed and had no hope of pollination at that late date.

Fall is mushroom season, and they were in full exhibit out around the Eagle Beach area. Big moss clumps growing way up on the side of a cottonwood tree sported great tufts of white ‘toadstools’ (but no toads, up there). Alder stumps were covered with crowds of brown mushrooms (I fear I’m sadly ignorant about mushroom ID). Tough little bright orange fungi poked through the packed gravel on the trail. Purple coral fungi (I do know that one) were common in the forest, growing in groups of slender, pale purple ‘fingers’.

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Amanitas. Photo by David Bergeson

Beautiful, but poisonous, fly amanitas (or fly agarics) spanned all age classes from bumps newly emerging from the ground to decrepit and no-longer-beautiful old age. The cap comes in various colors: often red, but sometimes orange or yellowish. The ‘fly’ part of the name may come from an Old World custom of putting pieces of this widely distributed mushroom in a dish of milk; this apparently attracts and traps flies. Despite their well-known toxicity, many of the mature amanitas had nibble marks around the edges, where squirrels or mice had snacked. Amanitas are important components of the plant community, because they form mutualistic associations with many trees, providing nutrients to their partners and sometimes serving as links for transport of nutrients and defensive compounds between trees.

There was plenty of bear sign: tracks in the mud, a few scats with undigested high-bush cranberries mixed with vegetation fibers, and numerous shallow digs. Some of these digs had turned up clumps of the white nodules of rice root (a.k.a. chocolate lily), but these remained uneaten. Instead, the bears may have been after angelica roots, but that’s a guess, because there were few identifiable remains. Small brown slugs festooned themselves over the digs, enjoying the decaying leftovers.

We found two of the small brown slugs engaged in some sort of sexual activity. They circled each other, with penises erect, for many minutes. We went off to look at something else briefly, and when we returned, they had each gone their own way. So we don’t know if they were just thinking about mating, or if they were engaged in some post-mating display, or what. Slugs are hermaphroditic, meaning both male and female (Hermes was the Greek god of travelers and the handsome messenger of Zeus; Aphrodite was the goddess of fertility and love), and mating is generally reciprocal. After mating, slugs of some species chew off their mate’s penis, but there are many kinds of slugs, and I don’t know if that curious habit applies to these. One might well speculate about how this habit came about!

As the temperatures dropped below freezing around the high mountain peaks, the water levels of our glacial rivers dropped markedly, leaving sloughs and sandbars and exposing interstadial wood from forests that grew in the valleys before the Little Ice Age glaciers demolished them. We surprised a dense gang of gulls and six or eight ravens gorging themselves on stranded salmon carcasses in a slough beside the main river. Farther upstream, a broad sand bar had hosted a wolf party that apparently involved some dancing. One of the cavorting group had left enormous tracks in the sand, some of the largest we’d ever seen. What fun!

Bits and pieces

observations of mallard chicks, mosses, and the raven-eagle interface

Sometimes my local peregrinations don’t yield a suggestion for an essay on just one thing. Instead, I get a little scrapbook of unrelated vignettes on various topics. Here is one such scrapbook:

A friend and I were watching a brood of young mallard ducklings on one of the Dredge Lakes. No attendant female was evident for quite some time. Then in flew a female, calling as she descended. Every duckling immediately perked up and, in a bunch, they all rushed over to her, peeping all the way, as if to say, Mama, where were you? We missed you!

This same mallard family was peacefully foraging along the shore a few days later. We heard a sudden ruckus, as the female was loudly protesting something. We peered through the brush and saw a bald eagle swooping down over the ducklings. At each pass, the fuzzy youngsters dove frantically beneath the surface of the pond. The buoyant ducklings popped back up to the surface as soon as the eagle went by. One, two, three passes, and the empty-fisted eagle retired to a tall spruce to rest and reconnoiter. After a few minutes, the eagle tried again, three or four passes, with no luck. Then it gave up. These mallard ducklings were more fortunate than merganser families that can often be seen in Mendenhall Lake. Sometimes eagles wipe out entire broods of unlucky mergansers.

I always enjoy watching ravens in the grocery store parking lots. Perched up on the lamp-posts or along the edge of the roof, they flirt and gossip and groom and wait for a likely-looking pickup truck that might have something interesting and edible in the back. This strategy must pay off fairly often, because the birds keep on watching and investigating. One raven was seen near a local thrift store, where food was not likely to be discovered. But this hopeful (or desperate?) bird was hopping into the open trunk of a car that was merely delivering donations to the store. No rewards there!

Recently I watched a raven, yelling and fussing, chasing an eagle for several minutes. I did not see the outcome of that encounter, but a friend saw a similar interaction, with a visually pleasing (to the observer) outcome. In this case, when the chase was over and the eagle departed, the raven indulged in several barrel rolls and half-twists, in which it was soon joined by another raven, probably its mate. I have to think that the aerobatics were a kind of celebration. Ravens are known to raid eagle nests for the eggs, and now I wonder if eagles reciprocate, trying to snatch raven chicks, causing parental ravens to defend their broods. After all, they were recorded, a few years ago, grabbing heron chicks from the nest.

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An uneasy truce? Photo by Jos Bakker

I was reminded, just the other day, of some very interesting and pretty mosses. Most mosses produce dry spores in small capsules that open to let the breezes waft away the spores, to land more or less at random. But some mosses disperse their spores differently, in a way that greatly improves the chances of a spore landing on a patchily distributed substrate that is suitable for germination and growth. These specialized mosses produce sticky spores that do not fly on the wind. Instead, these mosses produce scents from the expanded base of the spore capsule, and the aroma of carrion and decay attracts certain flies that commonly feed on dung or, in some cases, rotting flesh and bones, usually of mammals but sometimes of birds. The flies land, the spores stick to them, and the flies carry the spores to another dung pile, which provides the necessary conditions for the germination of the spores. I’m told that some of these mosses carry specialization one more step: some depend on herbivore dung while others focus on carnivore scat. Making sure that the spores arrive in a good spot is a nifty way to increase the success of your offspring!

Finally, here’s a little mystery. I have observed that robins rototill moss beds, in search of small invertebrates. Ravens and crows sometimes pluck hundreds of tufts of grass and moss from broad reaches of lawns. Mallards grub up square yards of moss and debris, in search of spilled seeds from a bird feeder in early spring. And bears rototill more deeply, in their quest for the roots and stem bases of northern ground cone. But deep in the forest this spring, a friend and I found many places where some creature had scuffled up big patches of leaf litter. Most of these places seemed to be where snow had stayed a bit late and few green shoots were present. This is not good habitat for robins or mallards, and the scuffled places seemed too shallow for bears. The question is Who did it and what were they searching for?

Birds at my feeders

musings on chickadees, ducks, and mallards

A gang of four Steller’s Jays regularly attends my seed-feeding stations. As soon as I go out on the deck to replenish the seed supply, they are there. One of them lets out a loud, raucous call, and then the rest come piling in, scarfing up the biggest and best seeds. After they’ve picked out the peanuts and sunflower seeds, they may take some of the little, round millet seeds, but these are usually left for the juncos.

The jays have even figured out how to raid the cylindrical feeders that I hang over my pond on a pulley system. They aren’t very graceful about it and they have to flutter their wings a lot just to stay in position, but they get enough sunflower seeds to make the level in the feeder go down rather quickly. The chickadees and nuthatches have to work around the big jays. Nevertheless, the little birds seem to do very well; there is a constant flurry of at least six chickadees whisking between the feeders and the nearby spruce trees. Whatever they reject, as they sort through the sizes and shapes of the seeds, drops down into the pond, where a gathering of mallards squabbles over each fallen seed.

Although the raucous blue rascals rather hog the show at times, they can be useful as well. One day they all worked together to harass a sharp-shinned hawk that was looking for lunch, with its eyes on all the birds congregated at the feeders. The jays swooped at it, squawking and shrieking, so all the birds knew it was there and were very wary. Eventually the still-hungry hawk gave up and left.

Jays aren’t always the ‘top dog’, however. At my feeders, when the resident squirrel approaches, on its regular rounds, the birds all move to another feeder temporarily.

Some squirrels have to work harder: A friend has observed another squirrel regularly checking seed feeders on the deck. It hasn’t quite figured out how to extract the seeds from most of them. Nevertheless, it energetically chases away the jays and other birds that come there to feed, spending a considerable amount of energy without gaining any food.

In addition to their other tricks, jays are accomplished vocal mimics, and they use this ability cleverly. They can mimic crows, red-tailed hawks, eagles, and goshawks, for example, and do it well enough to fool expert bird-watchers. A jay giving one of the predator calls generally causes other nearby birds to scatter. That potentially leaves the deceitful jay with sole possession of a food source, such as a seed feeder. A sneaky way to compete for food!

Jays also mimic marmots. Why in the world would they do that?? Marmots are not competitors for food, to be startled into fleeing. Could it be that jays simply entertain themselves, giving that active brain something more to do?

On the morning after the first hard frost, my pond had a sturdy film of ice. So the ducks were out of luck, in terms of a refuge from shooters on the wetlands. And I thought that they would all stay away from the frozen pond. But one persistent male mallard thought otherwise: he skittered and skated over the ice, snapping up spilled sunflower seeds. He had the place all to himself. A few days later, a light snow had coated the ice, and duck footprints were concentrated under the hanging feeders. Then I noticed that a female mallard had trudged up from the creek and over the ice to gobble up sunflower seeds. Relations between male and female seemed to be amicable, but occasionally the male selfishly chased the female away from the best clump of seeds.

A few days later, I glanced out my window at deck railings covered with snow and spruce branches weighted down by great clumps of snow. The pond was now frozen, so the heron that stalked the shallows a few days before was gone, and so were the opportunistic mallards. All the smaller birds were still here, including the rowdy jays.

It was very cold, so that was a nice time to remember some of those all-too-rare sunny days of summer. In the accompanying photo, two jays are enjoying a salubrious sunbath. I wonder if jays use any brain space in remembering such things when the weather turns icky!