Sunday, November 6, 2011

October 18 to 25, 2011

October 18 a blustery morning and we hoped to time our arriving at our land just as the sun broke out in the late morning. Not quite. While it was too wet for me to saw firewood, I could move it, and, of course, I could take a look around. As I walked down the road, I checked the Deep Pond to see how the beaver responded to the relatively heavy rain we had last night. The pond was definitely higher and the beaver heaved up more than the usual amount of mud on the dam.

This bit of work deserved some close-up photos,

And coming back along the dam, I took a photo from the other side of the old gap in the dam.

The question is, how long will the beaver rely on mud and stalks? It doesn’t have to go up on land and cut a tree to get logs. There are probably plenty of old ones on the bottom of the pond, and it has already pushed up one that was nearby. Because the water is higher, it is not as easy walking along the dam. I managed to get over far enough to see another stretch of mud work.

Of course, the beaver might be right. In a dam like this which supplements the bank of a man-made pond (not by me), stalks and mud might do the trick and best stabilize the bank.

Many call beavers “engineers” but I’ve never heard of any human engineers doing an analysis of the beavers’ various dam management techniques. Photographs of their work make beavers out to be artists. I couldn’t conveniently go farther along the dam but I took a photo of the next area of work, and I think it is the first time the beaver addressed that area.

Perhaps sensing that the leaky parts of the dam are under control, the beaver is starting to push mud up all along the dam, which beavers commonly do and which can make beaver dams rather large ripples in otherwise flat terrain. Meanwhile there is much less vegetation behind the dam

And much less in the pond.

However, with higher water vegetation is flooded over. In the summer it grows up to the surface, but growing season is over. The best measure of how many lilies the beaver ate will be next year when we see how many remain but here is how the pond looked back on August 8th.

The one advantage of having the vegetation thinned out is that it is easier to study what the beaver leaves behind. Today, I saw bit of lily rhizome that the beaver usually eats in toto.

And closer to shore, I saw all the stringy parts of the rhizome the beaver doesn’t relish.

I also sat in the chair by the dam for a half hour or so. When the sun was out the red dragonflies flitted on and off me, and soon enough nine were stuck on me, including two pairs of dragonflies.

When the clouds moved in, it suddenly felt chilly. Most of the dragonflies on me hunkered down and stayed. When I had to get up, I shook my arm gently, and most left. But one pair stuck to my jacket. I blew on them gently and the one in front seemed to get ready to go, but the one behind seemed dead to the world, with its head bowed down. It crossed my mind that a dragonfly tail was not that heavy and that maybe the rear dragonfly was dead. Its tail looked pale. If it was dead, what would happen next? I moved my arm and the rear dragonfly stirred. When I stood up the pair flew off. Then I saw another dragonfly pair on the other chair we have down there. The front dragonfly looked lively but the one behind was quite dead, ghostly pale.

The dead fly’s legs were clutching the tail of the live fly. I should have made a closer study of this. But I think what I saw is apparent. The dragonfly body is light and its wings are strong. Not sure why this dragonfly was saddled with this strange memento mori. One of the dragonflies that landed on me brought a meal with it, a tiny flying insect, I would have never noticed. It was no bigger than a blackfly yet had shell like wings. Perhaps it was a tiny ladybug. I wasn’t sure what the dragonfly kept trying to chew, some part of the body not wings. When the dragonfly flew off the little bug stayed on its back, legs wriggling and one wing twitching. A gust of wind blew it off my pant leg. Going up the road, I noticed a large nest in the tangles of one of the many grape vines hanging over the side of the road.

As more leaves fall down, we’ll be seeing many more nests.

October 19 we went up and over the ridge on Antler Trail and whenever we went through any brush one or both of us picked up some deer ticks on our pants. When we got down to the little causeway on the South Bay trial we saw a white throated sparrow and some kinglets in the bushes. Our hike on the trail around South Bay was uneventful, no ticks and no otter scats. We went up to the Audubon Pond embankment and saw that the beavers had cut down two trees at the east end of the embankment. I think I had seen one a few weeks ago. The other had been gnawed a bit but not cut down.

Now the beavers had it down, branches trimmed, segments seemingly measured out and at least one log cut off and taken away.

I didn’t see any other work in that corner of the pond. The pond itself looked quite full with water going down the big drain pipe but the pond below had been destroyed. For some reason the people running the park opened the dam below and carted away all the mud the beavers pushed up to make the dam and spread the dirt in the flatter area below the dam.

I’m not sure why they did this. The beavers can make the dam again, but I’m glad they didn’t put a pipe through the dam. There was some gnawing on another large tree and a tree a bit smaller had been cut down since I was last here.

There are power lines about 50 yards downstream so perhaps they simply want to persuade the beavers to quit the valley. Anyway, on the Audubon Pond side of the embankment the beavers are amassing a cache of branches outside their new bank lodge for their winter dining,

And they seem to be better fortifying the burrow into the bank which evidently goes under a juniper bush. I remember coyotes once rolled in the snow here and it is possible they were attracted to the spot because they dug into the burrow below when muskrats used it. Now the beavers may be patching those hole, not that I ever saw any holes, but I didn’t really look. The beavers have brought mud and logs up on the bank there.

Glancing over toward the west shore of the pond, I could see that the beavers cut down some trees there, but I wanted to check the otter latrine above the entrance to South Bay first. It looked about the same as last time but today I saw a patch of grass with three scats,

Here is a photo of one of the black scaly scats,

And a small loose brownish scat.

I share the photos to show how different these scats are from the ones I saw at the East Trail Pond, which doesn’t necessarily prove that they came from different otters. An otter could get from the East Trail Pond to this slope over looking the entrance to South Bay faster than I can but in my mind at least, I see more otters -- a family of 3 or 4 in the interior of the island, 1 or 2 adults working the bays, maybe just one given the lack of scratching in this latrine.

Then I went back up the trail and walked around Audubon Pond. On the south end of the west shore of the pond the beavers cut down a shag-bark hickory.

At this relatively small size the trunks of the tree don’t look too shaggy. This is just the size the beavers like to cut down.

I think their cutting hickory is more a sign of their desperation than of their enterprise. However, these beavers have been cutting hickories here now and then for the last two years. When beavers left this pond in 2001, one theory I had was that they couldn’t bring themselves to cut the many hickories, but I had a competing theory. An adult beaver died here, likely of disease, I found it a few yards from a hole in the ice in the middle of winter, and that may have prompted the other beavers in the family to leave. Anyway, as I expect I shall see, beavers don’t get as much out of hickory as they do from other hardwoods like red and white oak and as of now no branches have been trimmed, no bark eaten. There are groups of sizeable trees out on a grassy point a bit farther up the shore, and the beavers cut the smallest down and began some low girdling on a pair of larger ones.

The beavers are continuing to cut trees in the woods west of the pond

and segmented one 20 foot tree right in the middle.

While I always enjoy photographing the beavers’ tree work, I no longer pay enough heed to the species of tree and I never measure the extent of their branch trimming and log cutting. It would seem obvious that the species of tree makes a big different to beavers but as beavers shop for trees the size and location of the tree may be more important. I rarely see beavers clear out one species of tree even though they are capable of it but I have seen them clear out trees of a certain range in diameter. As for how much of the tree they use, that suggests a moral imperative I don’t think we should impose on beavers. By looking at lodges and dams, one can see the size of logs that beavers use. Hefty logs 20 feet long and 100 feet from the pond will not be used. It is typical for beavers not to come back and segment long logs one finds lying in the woods. Beavers move on to another project and often don’t return to old ones so if one log is cut and 5 are left behind, so be it. Statistics describing foraging push science into economics which is a totally human misadventure designed to shape more than explain human behavior. A cursory glance a civilization should convince anyone that humans are far more wasteful than humans, and increasingly so, yet our own measure of our productivity and efficiency just keeps getting better. That long aside said, the beavers also began gnawing a smaller maple,

And I think they will soon come back to this and at least cut the tree down. However there is as yet no well beaten path to this area. I also wasn’t paying that particular attention to the beaver work because I was hoping to see fresh otter scats here, and hoping that by its texture I could get a better feel for whether the interior otters or the bay otters came here. There were no scats in their sometimes latrines along the west shore and by the bank lodge there. And I didn’t see any on my way out to the bench on the north shore or on the bench where the otters often can’t resist to poop. No signs of beavers being around there either. Then as I walked back from the bench I saw two otter scats in the grass

just back from the bench.

The scats were neither like the ones I just saw along South Bay nor the ones I saw two days ago above the East Trail Pond. But they were more like the former, perhaps a few days older. Otter pups seem to find this pond very congenial and from what I’ve seen of their behavior here over the years gives them good training in catching bigger fish without having to deal with the much wider scope of the bays and river. (That said, it’s been a couple of years since I’ve seen signs suggesting pups have been here and several years since I’ve seen pups here.) So I headed toward the East Trail Pond via where I had seen otter scats by Meander Pond last year and scats between Meander Pond and Thicket Pond last year and this summer. I first went on the Short-cut Trail which brought me below the dam of what I used to call Short-cut Trail Pond which is now a huge meadow.

Here is how it looked in the winter of 2000, before otters put a hole in the dam which the beavers there did not repair.

I didn’t see any otter scats near Meander Pond dam nor at the end of the canal south from the pond where the otters latrined a couple of times last year.

However when I went over to the old trail, used by many animals including me, coming up from the Meander Pond canal pointing east toward Thicket Pond. I saw a series of grass piles that had the elan of the scent mounds I saw at the East Trail pond two days ago, though the material, dead grass, was different than the moss and pine straw mounded at the East Trail Pond.

The photo above gives no hint of what I saw. A close-up of the scent mound closest to the canal gives a better idea.

I strained to find some scat and did find a little squirt on the edge of that pile of grass.

Walking slowly up the trail to Thicket Pond, I didn’t see any scats by the other grass piles. There was some scratching down to dirt and then farther up away from this recent otter activity, I saw some older otter scats, that I had not seen before.

But up at Thicket Pond, the grass closed over the trail and I didn’t see any scats.

I am beginning to think that Meander Pond marks the western edge of the home range of these otters, and that Meander Pond last year and Thicket Pond this year served as natal ponds for otter pups. I will never be able to prove that and I am not entirely comfortable with the idea. I like to think of otters as being bolder even at that period when for mother and pups seclusion is necessary. But if I am right, it shows how adaptable otters are, adjusting to so many of the ponds on this end of the island turning in the meadows -- in part because otters put holes in dam during the winter. I have never seen fish in Meander Pond and Thicket Pond. However they are flush with frogs and I assume larvae and insects. I ignored the beaver work at the East Trail Pond (I had a few more miles to go beyond that and it was threatening to rain) and checked the otter latrine on the north shore of that pond. I didn’t see any new scats or scent mounds. There was a lump of moss in the rolling area that wasn’t there two days ago.

I’ll attribute that to gravity. I still scanned the pond for otters -- there were 8 wood ducks in the pond who flew off when I arrived. I took a photo of the lodge, which certainly looked like a comfortable place for otters to rest.

Not that there was any visual evidence seen from afar that they did. Otters generally level a small space or two on the lodge, and maybe even pad it with vegetation. To cross the old middle of East Trail Pond, now all meadow, I used remnants of the old boardwalk that was once part of the East Trail. I didn’t see any otter nor beaver signs along it. I checked likely otter latrines around the pool of duckweed covered water behind the old East Trail Pond dam.

There were no signs that otters had been there. I also checked the foot of the ridge that was the major latrine here. The otters used to go up the ridge as a short cut to Otter Hole Pond.

What a network of fish filled beaver ponds the otters once had! I crossed the Second Swamp Pond dam where the otters latrined even as that pond almost drained away a two summers ago. The grass was greener where the otters latrined, but high grass everywhere along the dam showed that no otters had rolled there in some time.

I have not been here in many weeks and was surprised at how much the dam had deteriorated. The runoff from the recent rain made a four foot wide stream where early this year I could still easily cross. I was lucky enough to find a couple half sunken logs to dance across so my boots didn’t get that wet. When I got up to the Lost Swamp Pond I was immediately struck by the grayish brown silty cast of the water almost everywhere in the pond.

It looked like a huge flock of geese had foraged through the whole pond. Then I worried that there was some human activity up pond bringing silt down into the pond. So after seeing no new otter scats in the latrine next to the dam. I went around the west end of the pond so I could get a view up into the private land from where the creek feeding this pond comes. Nothing untoward up there, but only the usual small flock of geese. At the mossy cove latrine, I did see some new otter scats.

That would usually prompt me to linger so I could watch the pond and think about what otters might have been up to here, but it started to rain. I pressed on to the Big Pond and as I crossed along the dam in a driving and rather cold rain, I saw three large flocks of geese almost filling the pond. As I hurried along the dam, I heard them discussing what to do and before I got to the south end of the dam, the majority honked "go", and I stopped and watched about 200 geese fly into that same driving cold rain that was wilting me. Good hike.

October 21 when we got to our land in the morning we walked down the road to White Swamp and saw that a beaver is back cutting willow branches.

The water near the road was muddy but no signs that the beaver has done anything with the heave of mud and grass out in the pond, which I am not sure if a beaver or muskrat fashioned.

We’ve had enough rain for a small pond across the road to flood a good portion of the surrounding pasture due to a narrow culvert under the road. We saw a turtle walking across the road going from the swamp to the flooded pond. We got to it in time, and the Blanding’s turtle retreated into its shell. We checked its bottom and saw that it was a male.

We only noticed the two blobs under the shell after we looked at the photo. I think they are leeches. The turtle was not happy with this rude treatment, but it didn’t have far to go to get to the safety of water.

The beaver in the Deep Pond has reacted to the rain by building up the dam with old poplar logs that it brought up from the bottom.

A couple years ago I cut some poplar up near our garden, cut them into sizable logs and threw them in the pond near the dam for the two beavers then in the pond. Judging from how much water I had to bail out of my boat docked on the island, we just had from 2 to 3 inches of rain. I went down to the old beaver development to see if the ponds filled up there. The Last Pool had enough water to show the two channels the beavers had through the pond.

The canal going down to Boundary Pond was full where the beaver had dredged down two feet,

and where the dredging had not been as deep, there was once again a semblance of a pond.

The “hut” that I think a beaver fashioned in the middle of that area looks ready to use, though I never saw a beaver use it. Seeing it almost covered with water now, I still have trouble figuring a how a beaver used it. There must be a pocket of air at least if not a platform to sleep on up under those sticks toward the back of the “hut.”

I saw what looked a bit of wet muck toward the back of the hut, and while I am not sure how it got there, I saw no signs that a beaver pushed it up there. There was more water in Boundary Pond. The water expanding into pools in the upper end of the pond looked like air filling old lungs.

The lower pond had resumed its old shape. If beavers repaired the dam, more rain would back the water up over the grassy area I’ve been nosing over the last few months looking for rare plants.

I had to go up on the ridge in order to get a look at the lodge and dam. Because of this watery inflation, the duck weed has broken apart into several green continents revolving around lodge.

I took two photos of the dam. The first shows how high the water is on it, and it is easy to see that for all my enthusiasm for the influx of water, the pond lacks two feet at least before it can assume its maximum extent and depth.

The second photo shows that the only water leaking through the dam flows out at the center down into the old channel through the valley.

I walked across the dam and heard the water gushing out there. No sense taking a photo as there is no visual explanation for why the water is flowing there. In leaks in other dams, I’ve often felt that I could repair it if I jumped into the water and put both hands to work. (I’ve only tried to repair a dam once, and made a botch of it.) But this leak is mysterious to me. Leslie thinks water is running out along a root, but why would that develop right after the beavers left? The mass of logs and branches the beaver pushed over the dam makes it impossible to look for any hole from that direction. And unlike mud, the humus or forest litter packed behind the dam tells no tales. A small animal might have burrowed into the dam and leave no impression. I suppose I will eventually prod the area where the leak is. I’m reluctant to do it because it may only make the leak worse. I’m hoping that vegetation in the pond, some of that duckweed for example, might plug the hole. I walked up the east side of the pond, under the girdled hemlocks. I didn’t see the need to take more photos of the pond. But I couldn‘t resist a photo of a mossy mound forming on top of a rotting log.

There was not much water around the north side of the lodge, and with the pile of stripped logs there left by the beavers that part of this pond would need some work before it could accommodate beavers again.

There is a steady stream of water coming down the valley and into the pond.

The water flows through the pond in a channel where beavers could easily swim.

Seeing the pond regain a semblance of life and yet remain beaver-less did not depress me as much as I feared it would. It seems to offer hope for the spring especially if that hole in the dam stopped up as mysteriously as it opened.

October 23 - 25 between the raindrops I confined my nature observations to keeping tabs of the beaver’s work on the Deep Pond dam. As well as pushing up some old poplar logs, the beaver is lacing the dam with vegetation.

The last time I checked there was a good bit of water flowing through the dam despite the beaver’s repairs. Now the flow was minimal and I could easily walk below the dam and check the next part of the dam the beaver had started to refurbish. Here the beaver seemed to push everything including the kitchen sink, which is to say that I’ve never seen a juniper branch pushed up on a dam.

Beavers generally use branches and logs without leaves. Live junipers always are thick with green needles. The beaver pushed the branch up just like beavers push up any branch with the crown facing the pond.

On the 25th the sunshine returned. When I checked the dam, I saw that after pushing up all that vegetation, the beavers mortared over a neater layer of mud. However, the juniper had not been covered with mud.

To jump ahead a bit, by the 27th, the beaver had just about covered the juniper with mud.

And the popular logs in the first gap were almost mudded over, and more vegetation pushed up there.

Meanwhile back on that sunny day, the 25th, the little red dragonflies seemed to appreciate the sun more than we did and I hated walking over the poplar log behind the dam where they were all lined up.

Through rain and shine, we kept walking up and down the road at our land, and I noticed that a beaver came back to take another bite off a willow that it had first cut a few days ago.

However, I didn’t see much muddy water or other signs that beavers continue to forage there.

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