Visiting the wetlands

toad ponds, goose foods, and owl pellets

Instead of the more usual approaches via the dike trail or Industrial Boulevard, we went in via the public access off the Mendenhall Peninsula Road–down the slope through the bear-clawed alders, past the deer-nipped skunk cabbages, across a swamp. Under some sprawling roots we found a heap of mallard feathers, where some ground-predator had enjoyed a meal. Off toward the end of the peninsula lie several shallow ponds, where toad tadpoles could be found in summer, but I don’t know if toads still use those ponds.

Finally out on terra firma again, the beach rye was barely beginning to send up green shoots. We could hear Canada geese talking to each other in several portions of the wetland. Where the beach rye thinned out, and especially in patches of some smaller vegetation, there were thousands of shallow divots in the damp soil, along with lots of evidence of goose digestion. We watched a flock of foraging geese for a while, observing that their head motions indicated digging and clipping. Of course, we had to see if we could determine what they’d been grubbing up!

goose-dig-kh
Photo by Katherine Hocker

Near many of the divots we found discarded lumpy rootstocks (if that’s the right word) that often bore a thin green shoot; the tap root was cut off. A few of these green shoots had matured enough that we could discern the shape of the developing leaf, which suggested to us that this favored plant was silverweed. We then sought some intact silverweeds and grubbed them up (my fingernails may never be the same again). Oh yes! It’s silverweed. I tried to pull up some of the taproots and discovered that they are very reluctant to come out of the ground, but the geese can break them off. In the bottoms of the divots we could often see the snapped-off lower part of a tap root, and by looking at the intact plants, we could see that the geese were selectively feeding on the upper part of the taproot, just below the lumpy rootstock.

Our education continued when we consulted Pojar’s book of regional plants. Indigenous people have long used silverweed for food and medicine. In some cultures, the tap root (cooked) was eaten by high-ranking men and the lumpy rootstock was given to commoners. So the high-grading geese knew what they were doing, so to speak, but I have to wonder why they so often rejected the lumpy part. According to other sources, silverweed is also known as goose-wort (even its scientific name indicates association with geese!), because it is a favored food, and we were merely late-learners. A residual question lingered: could the discarded rootstocks take hold and regenerate the plant?

The geese offered us another puzzle too, but this one remains unsolved. Many of the goose feces that were scattered on the ground had a strange look, with lots of short, thin, red bits. So I picked up a few and broke them open. They were full of mashed up green material (no surprise there) and the little red pieces. With the help of a hand lens, we could clearly see that these scats were chockful of moss! The red bits were stems, some still bearing their moss-leaves. Who knew that geese eat moss—and in some quantity!

There were many other treasures to be found by curious naturalists. Feathers of a short-eared owl—taken by an eagle or shot by a human and later scavenged? Feathers of an immature glaucous-winged gull (this took some searching on the internet). Several owl pellets composed of vole bones and fur. Vole tunnels and runways and digging sites, usually deeper than those of geese. Porcupine scat on top of a stump; this is an odd place for porcupines to visit, but we do sometimes see them wandering about in the wetlands. Some of the stray white-to-tan hairs we found could have come from porcupines.

A few days later I returned to this area, this time focusing mostly on the wonderful miniature gardens growing on the old, stranded logs and rootwads. A weather-beaten blueberry shrub, a couple of thriving currant bushes, and a venerable elderberry bush had sent down roots. The diversity of mosses, lichens, fungi, and even slime molds on the old wood was impressive, considering that they are totally exposed to desiccating winds and (sometimes) sun, salt spray, sleet, and pounding rain. I have to wonder how this community of diminutives might differ from that on similar logs and rootwads under the forest canopy; to do this comparison using rigorous science would be very difficult (because of the many different microhabitats on the gnarly rootwads), but a more casual approach could be instructive.

Spring?

… it may be creeping up on us!

The days grow longer and we all start wishing that spring would be here NOW! Indeed, spring is slowly, slowly springing. Perhaps it got a bit confused by the lack of a real winter? Or perhaps we are just a tad over-eager.

There are, in fact, a few signs that the new season is upon us. The flocks of varied thrushes that fossicked about on the beach fringes have dispersed, and we now hear the familiar song from many points in the forest, as they set up their breeding territories. Song sparrows are singing, too, a trifle rustily, but soon to be in good voice. Steller’s jays are now seen commonly in pairs, and their calls are more varied than in winter, or so it seems. Hooters (sooty grouse) are heard again on the hillsides. The robins are back, but I have yet to hear their song.

The red-breasted sapsuckers are here, checking out snags and light posts, tapping on trees and houses. Canada geese are busily grubbing up sedges from the wetlands, picking off the sharp, protective tips of the new shoots and biting off the nutritious new growth. Various reports come in: I heard a ruby-crowned kinglet, saw an early hummer, heard a junco sing.

As the ice melts on my home pond, mallards again arrive, drifting in the bit of open water at the outlet, marching across the ice, scavenging spilled bird seed. Even though the millions (apparently) of pine siskins seem to prefer feeding on the massive spruce seed crop and the alder seeds, some of them visit the feeder hanging over the pond and messily select certain sunflower seeds, dropping hundreds onto the pond. Squirrels and mice, as well as the mallards, make good use of the rejects. And, I happily see ‘my’ nuthatches again, after a long seasonal absence.

The most exciting sighting in the bird way was a small flock of rusty blackbirds in the Dredge Lake area. As usual in my limited experience with them, they were poking about in a shallow, brushy pond. But I didn’t get to watch them for long; they soon moved deeper into the thickets. I don’t see them very often as they migrate through here to the north country. Unfortunately, their population has declined dramatically in recent decades, for unknown reasons, so they are getting harder and harder to see.

Rusty-Blackbird,-female,-by-Bob-Armstrong
Female rusty blackbird. Photo by Bob Armstrong

The plant world, too, is showing feeble signs of spring. Elderberry buds grow fat and shoots of cow parsnip peek up above the leaf litter. In some places, felt-leaf willow has borne fuzzy catkins for a week or two already. Blueberry shoots are ready to go, just waiting for the right moment. The first shoots of skunk cabbage to emerge from the muck were eagerly cropped by deer.

Mountain goats are back on the ledges near Nugget Falls. Beavers never really quit working this ‘winter’ but got busy every time the temperatures rose and the ice weakened. Bears, probably especially juveniles or males, have begun to emerge from winter dens: moms with cubs presumably wait somewhat longer, so the new cubs are strong enough to follow mom around the forest.

I can’t claim that spring has sprung, but it may be creeping up on us, all the same!

Canada geese

many subspecies, habitats, and sizes

A favorite sign of spring is a flight of Canada geese, winging northward in the familiar V- formation, talking to each other as they go. I hear them coming, tip my head back, and wait—and then there they come. Gradually the melodic calls fade away in the distance. There’s nothing quite like it!

A migrating flock of Canadas is a very familiar sight for many people. So perhaps it is not very surprising to hear someone say, as we are driving down Egan over Lemon Creek, “Oh look, the geese are back!!” But the geese seen there and elsewhere on the wetlands in winter and early spring are not migrants. They can be found somewhere on the wetlands at any time during the winter; an estimated five or six hundred Canadas spend the winter with us.

Vancouver-Canada-Geese-in-flight-by-bob-armstrong
Vancouver Canada Geese in flight. Photo by Bob Armstrong

These geese belong to a coastal subspecies, whose geographic range roughly coincides with the coastal rainforest. They are considered to be non-migratory, although these birds may make short-distance movements at certain seasons.

Of course, we have some migratory Canadas too, in season. One subspecies nests chiefly on the Copper River Delta, and passes through here, to and from its wintering grounds a little farther south. Another subspecies nests in the Interior, and part of that population winters in California, coming by us in spring and fall. In addition, there is the small Cackling Goose, which looks like a miniature Canada Goose but is now considered to be a different species; it can occasionally be seen here as it flies between western Alaska and California.

The entire species we know as Canada goose is widespread in North America. It is divided into several (or many, according to some researchers) subspecies. The birds of some subspecies are very large; for example the one that uses the Mississippi flyway averages maybe 4500g (almost ten pounds). The Cackling Goose is quite small, averaging roughly 1600g. Our resident birds, known as the Vancouver Canada goose, are intermediate in size, averaging over 3000g.

The Vancouver Canada geese nest in rather dense rainforest, unlike most other subspecies, which typically use open habitats near water. Vancouver Canadas usually place their nests on the ground (as do other subspecies), but sometimes the nests are on snags or in trees, as much as 15 m above the ground. Some nests are in muskegs, and many nests are relatively close to muskegs and small pools of standing water. Nests are not necessarily close to ponds or lakes.

Male and female form a long-term pair bond, spending their lives together. During the month-long incubation period, when the female is incubating, the male commonly perches high in nearby trees, standing guard. Clutch sizes vary greatly, but often there are three to five eggs; older females usually lay larger clutches and larger eggs than young females.

Broods of Vancouver Canada geese use dense understory as escape habitat when threatened by potential predators. This is quite different from other subspecies, whose nests are commonly close to water and whose broods typically flee to open water. As the rainforest goslings grow, they are found more often in open habitats, not necessarily near the nest site. They often band together with other broods in crèches, which are thought to reduce the risk of aerial predation. Young birds stay with their parents though the winter.

Nest success can vary enormously, depending on weather and predator activity. For the rainforest subspecies, and for the species as a whole, as few as 25% of nests may be successful in producing goslings, but in good conditions, sometimes over 80% of nests are successful. Cold, wet weather is deleterious to nest success, and areas with many predators (for example, foxes, coyotes, ravens, mink, bears) may lose most of the nests. The age of the female also matters: older females are generally more successful than younger ones.

Although the geese may mature at an age of two years, some do not mature until they are three years old. If they are lucky, they may reproduce for several years.

After the nesting season, in late summer, Canada Geese molt their worn flight feathers, so for three or four weeks they cannot fly. In preparation for molting, Vancouvers typically move relatively short distances to selected, protected bays and inlets, where foraging is good. There they grow their new flight feathers in relative peace. Wachusett Inlet in Glacier Bay is one of molting sites; if you kayak into this inlet just after molting time, the water surface is covered with goose feathers.

Canada Geese are herbivores, grazing on many kinds of plants in the course of a year. The Vancouver Canada Goose likes skunk cabbage leaves in the nesting season; one can often see the bite marks on the standing leaves. They also eat blueberries, lingonberries, and crowberries in season. In late winter and early spring, the Vancouvers often forage on the roots and young shoots of sedges in the wetland. Most goose foods are not highly digestible or high quality, and the digestive processes of geese are reported to be moderately inefficient, so geese need to eat a lot. There are reports that they may sometimes snack on small clams and worms, drifting salmon eggs, and even dead salmon.

The need to eat large quantities of vegetation means that geese spend a lot of time just eating. A group of foraging geese usually has one or two individuals standing upright, as sentinels, to warn of approaching danger. If wandering people or dogs come too close, the flock will take off and seek a less disturbed foraging area. Flight is expensive, and the more the birds are disturbed, the more food they need to pay the costs of flight. So frequent disturbance makes it hard for them to get enough food.

During the hunting season on the Mendenhall Wetlands, geese become very wary and easily disturbed. In fact, observers have noticed that geese (and ducks) often leave the wetlands during the day and fly to Auke Lake, in order to avoid the hunters. They come back to the wetlands at night to forage. Unfortunately, these daily flights cross the paths of approaching airplanes—not good for either goose or plane!