Beavers III. Preparing for lockdown: filling the freezer

[Thursday November 26th 2020 is American Thanksgiving, and I wanted this post to arrive in time for the day, which is why it is coming so fast on the heels of my last one.]

My lockdown preparations include filling the freezer, but obviously I didn’t have to design and manufacture my own freezer. Beavers basically do. In the summer, they eat fresh green plants, but these don’t store well. However, their digestive systems allow them to eat the nutritious cambium layer of woody plants and trees, which can be stored just fine; these two photos show an oak tree recently cut by a beaver, and the cut surfaces of the tree were oozing sap on an unexpectedly warm day:

So how do they store them? The pond will be frozen soon, and it won’t thaw till the spring unless global warming intervenes. The beavers prefer not to emerge to forage on land, where they are vulnerable, so they lay down a stash of small and smallish twigs and branches, in a sort of floating raft, which they gradually weight down with larger branches. When the ice forms, this larder will be accessible from under the ice, and should keep them going through the winter months. In this photo, you can see the growing food pantry stretching off to the right of the lodge:

and a slightly closer shot here:

If you look carefully, in the right foreground there are larger branches sticking up out of the water. Their bottom ends have been rammed into the muddy bottom to help hold the cache in place. A couple of days later I took another look. They had added some larger stuff on top, to help weight it down so that their favorite foods stay sunk beneath the ice.

All of this is done at night, so all year I have not seen them at work. On November 15th this one was swimming languidly around one lodge, admiring his work (the beaver is what looks like a floating log on the right!).

A good thing too, since overnight on November 18th the whole pond froze, and in places the ice was thick enough to bear my weight. And today, November 25th, it snowed a little, transforming the perfect cone of the lodge into a miniature Mt Fuji:

Winter is here, and it is time for Thanksgiving, and to remember how lucky those of us are who have food in our freezers, and are still well and alive in this wondrous world, in this time of Covid.

PS There are actually three lodges on my pond, all fairly near each other, and all seem to be under renovation, but only two have visible food stashes. I don’t know if this is one family that has decided they’d like separate bedrooms, or if they are unrelated but willing to tolerate neighbours. You can see all three in this photo, though one is far in the distance, between the other two:

PPS The dam needs regular maintenance too, but this one is in good shape, so they haven’t done much to it this year.

A beaver’s work is never done II

[The second part of the beaver’s labor of Hercules. One more part will follow, on their food preparations.]

Now that the beavers have got everything ready, the construction project can begin.

The lodge may be a new-build, or a renovation of a fixer-upper. This year, it was the latter. This one is out in the middle of the pond,

so I took my kayak out to get close enough for a good look.

There is no intricate weaving like a bird’s nest, but the beavers create a rough tepee, and a hole is left open at the top for air to escape.

Once the structure is in place, they add a layer of mud, plastered down carefully:

More branches and mud get added as they see fit. Sometimes they seem to get over-excited and build higher and higher, like this exuberant creation, the Sagrada Familia* of Western Maine:

If this was a new lodge, once they have created a giant heap they would excavate the inside from underwater, creating a chamber for the adults and, hopefully, their young, who will be born in mid-winter.

Because they are nocturnal, I rarely see them at work, but eight years ago I captured this shot of a beaver building his abode, on the same beaver pond:

Talk about D.I.Y. I think I’d rather get the builders in.

* Sagrada Familia is a cathedral in Barcelona designed by Gaudí, started in 1882, and scheduled to be finished in 2026! It is famous for its pseudo-Gothic over-the-top extravagance:

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A beaver’s work is never done I

[This is the first of two or maybe three posts, that together tell a saga.]

It is November, and I am now cocooning, planning a bathroom painting project, stocking the freezer, and knitting a Christmas stocking for my granddaughter. But a beaver’s version of settling in for the winter is much harder work.

They survive the cold months largely inside their lodge, built of sticks and mud, with an underwater entrance. This is much more work than choosing the right paint color. The supply chain logistics are formidable.

First you cut down your tree(s):

If necessary, you drag them cross-country, including down steep hills, to the water’s edge:

You cut off all the small branches (see later), but don’t waste all that nutritious cambium. Then you chew off all the outer layers from the trunks that are too big to use.

The middle-sized branches and slender trunks are cut into pieces small enough to manage:

Finally, you float everything useful down the canals that you’ve created through the rushes, to your distant lodge:

Once you have your raw materials in place, you have two tasks. Get the lodge watertight and cosy, and lay down food supplies for the winter. And that is the subject of my next post.

Tufty caterpillars

Winter is coming here, and things are quieting down.  I will take the opportunity from time to time to show you things from earlier this summer that for various reasons I never sent out.

The world of caterpillars is one that fascinates the inner child in all of us, ever since we read for ourselves or to our children and grandchildren Alice in Wonderland, and then  The Very Hungry Caterpillar by Eric Carle. Some of my favorites.

This is a Yellow-necked caterpillar, Dayana minister, in defensive posture, holding on only with its prolegs and curving up both ends of the body in a perfect yoga pose. *

Yellow-Necked Caterpillar

The true stars of the punk caterpillar world are the tussock moths. This is a White-marked Tussock moth:

White-marked tussock moth

A Definite Tussock mothWhite-marked Tussock Moth, Orgyia leucostigma

A Milkweed Tussock moth, looking just like a miniature schnauzer:

Milkweed tussock moth

A Pine Tussock moth

Pine tussock moth caterpillar

And two Hickory Tussock moths:

Hickory Tussock Moth caterpillar

Caterpillars have very cool feet; the one in the photo below is traveling at full speed, so the first pair of prolegs are in mid-air.*  Olympic gymnasts on the balance beam cannot compare.

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Not so endearingly, the spines (setae) of tussock moths can cause skin irritation. Each spine (seta) has a tiny poison sac at its base.

Diagram of urticating seta and associated venom gland of whitemarked tussock moth (Orgyia leucostigma).

Figure 25. Diagram of urticating seta and associated venom gland of whitemarked tussock moth (Orgyia leucostigma). Redrawn from Gilmer (1925) by Jane C. Medley, University of Florida.

* Caterpillars have six true legs, like the butterflies and moths that they will become, and several further sets of prolegs, stubby short plump appendages that support the rest of their long bodies.

Fine feathers make fine ducks

During all that child-rearing that you saw in my last post, the male was sometimes around, helping out, but by July 2nd his breeding plumage was largely gone, and he was changing into “eclipse” plumage, a rather wonderful term for a bird whose glory has faded now that he has his mate. (Although I am not sure I want my current natural hair color to be termed my “eclipse” phase.) The white neck markings remain all year.

Wood duck

By the middle of August, the birds have dispersed, and I found this solitary male, now in full eclipse plumage, but still with his distinctive red eye

Wood duck

The eclipse plumage is short-lived. As summer starts to wane, they prepare for a new season. Instead of waiting for spring, they set out to attract the females even before the migration starts. This September 7th photo of a scruffy and embarrassed-looking male shows the first glimpses of the return of the breeding plumage

On September 12th , his head is getting there, but the rest of him is still pretty drab.

But look at him on September 2oth: the head is transformed, but the body is not there yet

Finally by September 26th he and his friend look like this, and this new attire seems to be pulling the birds, (a 1960’s UK expression, for readers too young to know), since they were accompanied by two females, one of which is in this shot.

Just for comparison, here is his outfit on May 12th, so he still lacks a few final touches:

But on October 12th, he is returned to his former glory, floating on the autumnal reflections:

PS: The mechanics of molting are quite complex. Like many ducks, there are two molts each year, in spring and fall. In the spring, only the body feathers are replaced, removing the bright breeding plumage and producing the more discrete “eclipse” plumage. In the late summer to fall, first all the wing feathers are replaced, simultaneously, meaning that for about three weeks they cannot fly. Then, once they are mobile again and able to flee from predators, the body plumage is molted and the highly visible breeding plumage comes back in. They are now ready to attract females again and pair formation begins. Because they are helpless for part of this long molting process, they often fly to special secluded molting grounds in the far north, returning to the breeding ground once the process is complete. But some stay in situ, as my photos show.

PPS: I have told this story as if I have been following a single male through his plumage changes, but of course I cannot tell one male from another, so I am sure it is a series of different ducks!