Wednesday, November 8, 2017

Chapter Two

Swamp Diplomacy?

Water flowing through a hole in a beaver dam   

In 1999 after five years of watching beavers and otters, I began sharing my experiences on the web and learning from others. A zoo curator getting her Ph. D. alerted me to the 1988 scientific paper I've already mentioned that recognized that otters commonly breach beaver dams. That paper suggested the otters' selfish motive that prompted their own sneaky amendment to the hydrological-beaver paradigm.


A half-eaten bullhead left on the shore of the Lost Swamp Pond

In the Journal of Mammalogy paper "River Otters as Agents of Water Loss from Beaver Ponds," the University of Calgary scientists who were so respectful of the beaver paradigm suggested that otters breach dams to make it easier to enter iced over ponds in the winter. Once under the ice with water flowing out through the dam, otters find "an increased area for effective foraging because of more extensive air cavities under the ice and an enhanced prey density because of decreased water volume." Plus fish attracted by the current might swim upstream through the hole.

That few wildlife biologists seemed to pay any attention to that 1988 paper shouldn't surprise. The recovery from three centuries of unremitting  trapping (except during wars) had just begun leading to a focus on the benefits of beaver dams. The ecological benefits of the beavers' wetland "engineering" was just taking hold and the hydological-beaver paradigm promising flood prevention and drought mitigation was in the offing. Otters were seldom seen.

I soon based a web page on that paper illustrated with my photos of the hole the otters made. However, I didn't make as much of my next surprise in the swamps: in March 1998 there wasn't a gapping hole in Otter Hole Pond dam even though otters were in and around the pond as much as they were in 1996 and 1997. 

I'm still thinking about why otters spared the dam in 1998. To say that they didn't all but drain the pond because there were not enough fish in the pond doesn't make sense to me. That's the point of making the hole, to make finding fish easier.

But does this make sense: in October 1997 I saw beavers in Otter Hole Pond confront a family of otters using the pond and make them at least temporarily retreat. At first I assumed that was business as usual in the pond and I was disappointed they didn't fight because that's one of the reasons I bought a camcorder. Then, over the years, as I kept reviewing the videos I took, I got this notion that the beavers and otters negotiated an agreement in the fall which guaranteed unmolested use of the pond by the otters in return for their respecting the lodge the beavers occupied and respecting the dam in the winter.

I can lighten the weight of your disbelief that I actually wrote “negotiated” by quipping that if you saw him floating in water Henry Kissinger would look a bit like a beaver.

Before telling the story, a brief digression: how can I imbue beavers with such gravitas? As early as 1995, I  saw something in beavers beyond their instincts that impressed me: their loyalty to the valley.

Although the beavers I watched didn't disappear under the ice like the ones Hope Ryden saw in the Catskills, I experienced the same rush of pleasure she felt when the beavers came out from under the ice in March. In 1995 during a warm night with a full moon, I peered down through the trees on the high ridge behind the Lowest Pond lodge to see if the beavers came out. The sound of beavers gnawing rose above the gentle symphony of a thawing valley and guided me to the perfect tree to sit behind halfway down the ridge. Through binoculars I saw five maybe six beavers hunched up on the melting ice around the pool of open water in front of the lodge. 

Once they were out and about every night, I expected them to repair the dam, but they didn't. It crossed my mind that the beavers might be done in the valley. Leslie who knew plants and trees better than I thought the valley had run out of beaver food, the birches, aspens and willows they prefer. The Lowest Pond got lower and lower and I saw no sign that beavers were using the lodge. South Bay just downstream was clear of ice. Did the logic of beaver development dictate that they venture out into the river to find another valley?

Then in April as I crossed the long dam of the Big Pond upstream from the Lowest Pond, I saw that beavers were back in that venerable old pond that I had passing acquaintance with for 20 years. They put five rocks on top of the mud they just pushed up on the dam. 

That the beavers retreated from Lowest Pond was the first evidence I had that beaver ponds can be sometime things, hardly lasting the season, but the beavers themselves seemed loath to leave the valley.
Beavers don't think about a pond, they think about a valley, the Big Picture. 

Realizing that caused a revolution in my thinking. Remember one reason I moved to the island was to simply sit by the Lost Swamp Pond which I thought must be the summation of beaver genius worthy of being put on the map with an official name. I thought sitting beside the Lost Swamp Pond was the closest I got to god. 

god in the spring of 2011

But I fell in love with it before I ever saw a beaver in it. That first full year on the island 1994-1995, I had to accommodate my worship to the reality of beavers. They change the view.

A lodge in the midst of it is what distinguishes a beaver pond. Every book about beavers seems to have a photo or illustration of the same lodge. Every time I went out to the Lost Swamp Pond the lodge looked different. The lodge swells in the fall as the beavers fortify it with mud and flank it with a half sunken cache for winter food, maple branches with yellow leaves shaking in the wind. In the early spring the branches are gone and the lodge is littered with leftovers.

after the nesting Canada goose leaves, weeds grow up from the mud and the white fuzz of the pile-wort (yes, a remedy for hemorrhoids) obscures the lodge by the end of August. 

 an old lodge sprouts a remedy for hemorrhoids

The beavers even amended the monumental 12 foot high dam. In July 1995 they built a small dam, that is, a six foot high dam below the 12 foot high dam making the big dam look half its true size thus ruining my story of how I discovered the Lost Swamp Pond. The pond below the huge pond was not much bigger than a VW bus and just looking at it nobody would believe it was six feet deep.

I began calling such pouches below the dams of big ponds “pools” or if they were shallow “wallows.” I soon saw that wallows extended the comfort zone of beavers. Beavers like to have their tail, feet and belly in water while they eat even if it is only 5 inches deep and they can't dive and hide. The pools probably help stabilize the bigger dam behind them. Plus in the case the Lost Swamp Pond pool after it silted up enough cattails began to flourish making it a sort of kitchen garden for the beavers.

Lost Swamp Pond dam in June
Contemplating the static pond remained on my agenda but seeing that the essence of beaverdom was change I got the urge to explore other valleys. The Lost Swamp Pond became just one more stop on my tour of ponds. One hot day in 1995 I pressed on from the Lost Swamp Pond dam to the north, backtracking my 1991 trail of discovery through some of the deepest woods in the park planning to angle down the Third Valley until I hooked up with the park's groomed nature trails, always the quickest way home.

I discovered a “carnage of the trees” between a shady pool and dark pond not half as big as the abandoned Lowest Pond. Yet that small pond appeared to have three large beaver lodges in it.

A small shady pond with two lodges

On my second trip to the area I saw that one of the lodges was a huge tree stump but I still couldn't figure what possessed the beavers to build two lodges of equal size, both as big as the Lost Swamp Pond lodge, right next to each other.

In the summer of 1995, while we took a car trip down the St. Lawrence River to the Bay of Gaspe, a micro-burst selectively toppled trees in a fury of wind and rain throughout Jefferson County. Right next to the pond I discovered were a half dozen toppled red oaks, all more than two feet in diameter crisscrossed above the pond as if victims of the micro-burst, but there was the telltale cutting of beaver teeth that angled into the trunks from above and below and all around about two feet off the ground.

Beaver lumbering is usually not this intense

The Third Valley was relatively high with a large rounded granite outcrop in the middle dividing a creek that collected water from the flanking ridges and fed and drained four granite lakelets now augmented by beaver dams. The top pond was a true beaver pond about the size of the Lowest Pond but as in the other valleys the beavers moved down to a smaller pond closer to trees they wanted to cut down.

Despite their two lodges to hide in, I bumped into three beavers there who looked large and unhappy in their small pond. That was puzzling because to the east, across the border of the state park was a long open valley, another watershed draining east to Lake of the Isles with a series of large beaver ponds. But beaver families don't share ponds with other beaver families. One reason they remain stubbornly where they are.

Whenever we got as far as the Third Ponds, we hiked down the valley to the west rounded the East Trail Pond, crossed a creek and followed the new East Trail up the ridge above the lush valley we once called Shangri-la. Just before we moved up, beavers dammed the creek creating Shangri-la Pond. The tangle of lush vegetation below had deflated before we moved up in 1994. Leslie blames porcupines for trimming branches and killing the hemlocks growing up the ridge thus letting too much light and heat into the valley. I blame a series of dry springs and summers for putting the creek back within its meager banks and drying out the valley. (Or did a spring stop flowing?)

We didn't blame the beavers for anything even though we could see the trees they cut below. They made their dam just below the confluence of two creeks, the short one from Shangri-la and a long one flowing seasonally down about a half mile from the plateau above Eel Bay. Shangri-la Pond mostly grew up the longer creek where the ground was lower and only flooded paradise a little ways passed the beaver lodge. One glorious fall day we sat high up on the ridge and looked directly down on two large beavers sleeping on top of their lodge, as if their kits were off in school just like our third grader and they too could relax.

The sacrifice of trees to the rising green-scummed water is a symbol of rot and stagnation, but not when beavers are in charge. To see beaver swim slowly through pond gave an impression of endurance that, I thought, must impress even the billion year old granite forming the walls of the canyon. In December a large turtle with a yellow chin and long yellow neck crawled out of the pond. That was our first meeting with a Blanding's turtle who commonly live 70 years. A beaver pond is no fly by night affair.

Once off the short ridge south of Shangri-la we would continue down a wide valley half woods and half meadow below a 50 foot high granite wall to the north of “The Meadow” mapped by Frank Hines in 1875. Despite all the persecution and pasturing that probably prevented beavers from moving up the small creek that flowed to the Duck Pond to the west, we found two oddly shaped ponds fed by springs at the top of the watershed of the creek. They seemed to be fashioned on terraces. Perhaps beavers of old terraced the valley.

Looking down at Meander Pond from the ridge

If so it was ancient history in beaver-time and as far as I could tell only helped the beavers we saw there by making it easier to dredge up mud for the dam and lodges and to make channels. I was dumbfounded to find that within two years of our moving to the island, a beaver family built a dam in front of the higher spring, then a lodge and then as the pond rose the beavers cut down birches and maples along the expanding shore line of the small pond. 

The birth of Thicket Pond
All that happened on top of the ancient terrace. In what I would call Thicket Pond the beavers engineered a simple and elegant solution at the top of a watershed where every drop of water was precious. Over the next decade I would learn a good deal from those beavers who refused to leave the valley.

But as far as I knew in 1998, none of those beavers had to contend with otters. In the past three winters I saw the trail of a few otters hurry over those snow covered ponds. I blamed the evident absence of beavers in the much larger East Trail Pond on the electrified dam. I never suspected that otters could be there because the old East Trail crossed the middle of it on a boardwalk and the new East Trail circled the west end of the pond and I knew that every footfall not to mention word could be heard throughout the pond. The books I read said that otters shied from people. I learned later that an otter family was seen in the pond, crossing the over the boardwalk in August in the late 80's or early 90's.

So while I sat by other ponds, the otters grew up in the East Trail Pond and then by September the mother began taking them to other ponds. Fortunately, in 1997 I was patiently waiting by the quietness of Otter Hole Pond where I rarely saw or heard people. I reckoned I would see otters there and I was right. In the fall of 1997 I bought a camcorder. The otters and beavers were so active in Otter Hole Pond I expected them to clash.

Tensions arose in large part because neither the beavers, otters nor I expected the beavers to winter in Otter Hole Pond. The hole in Otter Hole Pond dam from January to April filled Beaver Point Pond with water. 

Beaver Point Pond grew as Otter Hole Pond lost water

Sometime in the early summer the beavers built a lodge on the lower north shore of Beaver Point Pond. It is said that beavers build their lodges at night. I'll have to agree since I have never seen a lodge built from scratch. They just appear. The beavers continued to use the lodge in Otter Hole Pond too. While members of a beaver family do stay in the same lodge, they also break up and use different lodges in the same pond or adjoining ponds at least until the winter when they usually bet their survival on one lodge.

There's no way of knowing if the beavers built the new lodge in part as a reaction to the otters breaching Otter Hole Pond dam in February 1996 and January 1997. However, I think that experience may have affected the design of the new lodge. One trouble with the large lodge just behind Otter Hole Pond dam was that it was beside the old creek which formed the deepest channel in the pond. Otters often fish around beaver lodges and behind beaver dams because when the beavers dredge mud to build up the lodges and dams they make the pond bottom there deeper and thus more attractive to fish and otters. When water is draining out of the pond those dredged areas are the last refuge for fish.

So they built a lodge beside the bank of Beaver Point Pond. They also didn't make the mistake they made when they built a lodge beside the bank of what I called Upper Otter Hole Pond formed by that smaller dam soon flooded over by water backed up by Otter Hole Pond dam. They built that lodge right behind the dam dredging a deep and rather large pool of water beside the lodge and behind the dam where I saw many an otter family wear out during fishing lessons and then nap on the lodge.

But in Beaver Point Pond, the water around the new lodge was shallow and probably out of the way of fish. The beavers seemed careful to dredge just enough to make two all underwater entrances to the lodge. I never saw an otter on it. The granite outcrop between the dams to the south and north was always the place to scat and play.

Secluded Beaver Point Pond Lodge

Unfortunately for the beavers the end of summer was very dry. On August 2 I took two Canadian boys out to see the them. Although much is made of beavers in Canada, the fur trade took its toll and many Canadians have never seen one. We saw two kits just off the granite point in Beaver Point Pond seemingly munching on their first stick. But by the end of August I saw all the beavers back in Otter Hole Pond. The Beaver Point Pond lodge was virtually high and dry. Just as during the previous fall adult beavers cut down trees in the lower pond and hauled branches up to and over Otter Hole Pond dam.

On September first I took our old friend Bob Hunter on a tour of the ponds. When we lived in Washington and needed a quick communing with unparked nature, we drove 2 hours up along the Potomac River to Licking Creek just below Bob's place where there was a nice pooling of water deep enough to swim in. This was his first visit so I spent about two hours walking around explaining all the wonders I had seen though in the noon day sun of that day we only saw a muskrat in the Lost Swamp Pond.

We took our last rest sitting on the lower south shore of Otter Hole Pond over the otter dens in the granite jumble. I heard a noise below us from the rock and told Bob the otters were there. Sure enough, soon four otters swam out and went directly to the beaver lodge and seemed to use that as their base as they tried to catch fish. In my journal I wrote “They fished - played - tussling on sunken logs - hugging and biting necks, then swimming off. One caught a big fish and became the object of attention.” That “one” must have been the mother. I didn't realize then that not until late September or October do otter pups get the hang of catching fish. That evening we came back to see the beavers and saw four in the pond including one kit.

On September 3 Leslie and I saw the otters. Not much fishing, more tussling, and they went up on the lodge again and also scatted on the dam. Three days later we saw them again diving off the lodge.

Then as was often the case I didn't see them for a while in part because they weren't there, I could tell because they left no scats, which I was discovering could easily be seen, 

a fresh otter scat
and in part because we went off to visit grandparents. Then I saw otters again on September 23rd and 29th.

It is hard to describe the energy otters bring to a beaver pond as the fall progresses. Before settling on writing a history about what I saw, I took this crack at more emotive writing: otters veer and vector, ricochet and roll, climb and let fly casting their scent to the wind. They undulate, corral, wallow, celebrate and break fish backs. They arch their back; they chin up; they high tail; they screech; they chirp. They are flashy, flighty, flagrant, then flat asleep.

In a more sober word, they are in a hurry. That can best be calibrated by comparing them to beavers. Otter pups and beaver kits are raised differently. Both are born in the spring, beaver kits a bit later. But when the ponds freeze, usually between mid-November and the end of December, otter pups must be ready to swim and fish in the river which doesn't freeze until mid-January. Meanwhile beaver kits are ready to crawl into a lodge with their parents where they spend much time sleeping and eating what they can.

Although very cute, beaver kits are usually a negligible presence in the pond as their parents prepare for winter.

 A young beaver enjoying a stick
The otter mother and her pups are almost the same size by October. After all she has exhausted herself catching fish for them until then. By October they are almost equally capable swimmers in the confines of a beaver pond able to energetically forage in every corner of the pond.

Otters usually fish as a group bobbing in a kind of triangle or square formation. 

They dive into the water in a seemingly uncoordinated fashion which means any formation breaks up and then reforms usually after an underwater swim to another part of the pond. All their forming and reforming and diving and swimming has a quick beat measured by how the water roils because of them. Then whoever catches a fish breaks from the group and climbs on a floating log or the lodge or dam. Taking too long to eat a fish only invites other otters to come over for a bite of it.

Then the lot of them often climb up on a beaver lodge and take a nap. 

Pups are like teenagers full of themselves. They wind down into a relaxed state in a more active fashion than the mother, shoving each other and maybe even digging into the dirt on the lodge as if they can sculpt the lodge to make for a more comfortable nap. Beavers who might have tolerated the visits of an otter family in September might not in October.

In October, with my camera only good for snapshots, I pieced together a panorama of Beaver Point Pond,

which presented an impressive expanse. But the beavers there moved back to their lodge by the old creek, the deepest point in the neck of the valley, to spend the winter. One night I saw four beavers in Otter Hole Pond.
As far as I could see the beavers did not come out to watch the otters, but on October 9 just as I was getting a bit bored watching four otters napping, squirming and digging on the upper pond bank lodge, I noticed a beaver swimming down the pond along the shore. I was closer to it than the otters so its tail slap was probably directed at me. I kept an eye on the otters and saw that they didn't react to the slap.

The next day at 5 pm, armed with my new camcorder and accompanied by the sharper eyes of my 10 year old son, we first saw a beaver in the pond. The four otters swam down from the East Trail Pond in full force. We were standing above their rock dens and they swam right toward us, veered off, reconnoitered at the beaver lodge and swam back to the East Trail Pond.

The beaver we first saw in the pond went over the dam and another beaver swam down in the now golden pond from the direction of the Second Swamp Pond.

A week later when I got to the pond in the mid-afternoon I sensed that something was up. The brown body swimming up from Beaver Point Point was not an otter as I expected but a beaver and it dragged a branch over the dam and sank it beside the lodge. Then two otters came up on the lodge. They could have swam under water to get there. I saw two other otters swimming down the pond toward the lodge. A beaver blocked their way and slapped its tail. They whined more than screeched, swerved and dived into the water. An otter on the lodge whined then a beaver in the water on the side of the lodge away from me slapped its tail. An otter still climbed half way up the lodge and seemed to communicate with snorts to an otter just in the water at the back end of the lodge. Then they both swam up pond.

About a half hour later, I saw four otters swimming together in the well shaded northeast end of the pond. As they turned to go toward the lodge I lost my focus on them as I zoomed in (I had had the camcorder only for a week.) Then I heard a vehement otter screech and focused in on a beaver facing an otter as the latter somewhat pirouetted without quite retreating. There were a few more softer screeches and I could make out the four otters on logs.

The beavers swam toward them and with a few huffs the otters dropped off the logs and retreated,

and then the beaver turned and swam back toward the lodge. As he had been throughout the encounter, he was perfectly flat in the water, head and tail level. I waited expecting the otters to return for the third round, but they didn't.

Back to gravitas, after years of watching them I've seen beavers express alarm and displeasure. There's the tail slap, swimming back and forth with head up out of the water, and finally the lunge often ending in a shove accompanied with a hiss. 

A beaver shoves another beaver

The beaver I saw in Otter Hole Pond seemed to make itself more threatening by dispensing with all the ritual exhibits of beaver displeasure: no head up, no lunge, no tail slap. The beaver simply stopped in the otters' way in an enough said manner.

Seeing animals face off without further incident is common, but usually the face off is between the same species. If not entangled in a predator-prey relations animals usually ignore the other and go on their way.

Most observations of beavers reacting to otters involved protecting kits. In Lily Pond, Hope Ryden describes beavers moving kits from one lodge into another because otters entered the pond. Another spring she saw beavers drive otters away from their lodge with tail slaps. Perhaps the kits inside were too small to move. The beavers I watched got uncomfortable with otters in October when their kits were out in the pond every evening.

The movies and television shows we see about animals give the impression that they never have a dull moment. Otters are always chirping at each other and soon bump into an eagle, or a bear or a coyote. Beavers are usually continually engaged in their engineering projects and other animals in the pond appear as grateful beneficiaries. By 1997 I understood that mammals rarely make a noise and they rarely interact with other species except for a meal.

Encounters between the otters and beavers do not happen every day. Contentious encounters are very rare. Any encounter is significant.

By negotiating I mean that on that day the beaver acknowledged the otters' rights to the pond and limited those rights.In the journal I kept at the time, I simply described the encounter and observed: “Beavers seem bothered by the otters, but judging from body language are less intimidated by them than the otters are by beavers.” The more I thought about it, over the years, the more I am impressed that only one beaver stared down the otters. There were more beavers than otters in the pond. Apart from the monogamous pair and their kits, there were at least two yearlings and perhaps a two year old. Kits can be goofy but sub-adult beavers are feisty. The beavers could have stymied the use of the pond by one mother otter and three inexperienced pups. 

So to me, the essence of the negotiation was that one beaver met the four otters so the mother otter could show the pups that the beavers deserved a measure of respect and the beaver showed that by coming to confront them alone even when other beavers were in the pond the beavers did not want to escalate their sporadic tail slaps to the level of confrontation even though the beavers outnumbered the otters.

What did they negotiate?

I went back to the pond 48 hours after the encounter, and as if on cue, the four otters swam down the pond from the northeast. One otter that I took to be the mother dived into the water next to the lodge. The other three otters fished away from the lodge. When she surfaced, they all continued fishing without going on the lodge.

On October 26 the otters fished down to the lodge but didn't go on it or in it. Two pups climbed up on the cache of sticks in front of lodge, a nice place to make dive into the water. On November 5, they came out of the rock dens near Otter Hole Pond dam on a calm cloudy day so that every ripple in the pond was theirs, every point of light was true and not affected by wind or sunlight. The beautiful pond throbbed with their rhythm and shined with their brilliance.

They avoided the lodge. They found half submerged branches on the far side of the pond to hop up on and eat the fish they caught. When they fished behind the dam which was almost overflowing, they hopped up on the dam briefly. When they finally smelled me, they got into a huff and swam up pond for safety not into the nearby lodge.

So I think the otters agreed not to use the active beaver lodge. They continued to use their other dens around the pond. 

Then the otters grouped as a family disappeared, which I expected, happens every year. But that makes writing history a bit more difficult. For the beavers to negotiate a peace in October that maintained peace through the winter the otters that they dealt with in October must be those that planned to winter in the pond. 

Only by analogy can I even begin to prove that the otters who faced the beavers in October were the same otters who refrained from breaching the dam in February. During many subsequent winters I got the impression that otter families returned to ponds they used in the fall often staying in one for a month or more.

Tracks of an otter family on Second Swamp Pond

Through November I kept visiting Otter Hole Pond. On November 17, for the first time I saw the adult beavers diving beside the lodge and then getting their head above water and slowly paddling to the lodge and emerging with their two front legs, now serving as arms, cradling mud that they carried up to the top of the lodge and dumped. 

They didn't use their tail as a trowel, just their front paws and belly. Then they got down the now muddy slope of the pond without sliding.

Two days later otters returned, at least to Beaver Point Pond. November 19 and 22, I got my best videos of otters fishing in a hole in the ice in the middle of a pond. I saw two of them dive off the ice and emerge from the relatively shallow reaches of Beaver Point Pond with a fish big enough to lay out on the ice and nose down as it flapped.

In December, we were walking the South Bay trail celebrating a fresh fall of five inches of snow and I saw the prints of two otters going up over the ridge. We sneaked up and saw two otters nuzzling and sliding in the snow next to the unoccupied Beaver Point Pond lodge. They scatted on the lodge. Then they jumped into open water and disappeared under the ice. I went up to Otter Hole Pond and saw them come over the dam. They fished in the open water between the lodge and the dam, then saw me and, I think, swam upstream under the ice.

Since I only saw two otters at once each time, it is likely that they were not the otter family I saw in the fall. A few days later I saw the tracks of two otters leaving the pond and going back to South Bay.

On January 7 and 8 the St. Lawrence River valley from Lake Ontario to Montreal had a historic ice storm that paralyzed the area for a week and kept the island off the grid for 17 days (no charging the camcorder battery.) The jagged ice left on the ground by an ice storm, much of it falling down from trees, didn't make for good tracking. A week after the ice storm snow began to accumulate.

On January 16 I saw otter slides behind Otter Hole Pond dam, going to two holes in the ice from the rocks where they usually den. The pond was open at those points because there were two small holes in the top of the dam letting some water flow. At least that was my interpretation from afar. When I stepped on the pond to get closer I went through the ice. One otter trail rimmed the whole pond. I back tracked the trail across Beaver Point Pond, down to a high cavernous granite knob I called the Porcupine Hotel and out to South Bay.

In my journal I didn't speculate on which otters made the tracks which is good policy. What's happens next is the best clue to why what you just saw happened. On February 6 I walked up the south shore of Beaver Point Pond and then “eased” along Otter Hole Pond dam. Because of the hole through the top of the dam, there was open water on the upper side of the dam and “several dollops of otter pooh” around it. I even waited to see if any otter popped up out of the water. 

I went back the next day. Ten degrees at night and 20 during the day made for perfect hiking, but that's cold enough to ice over the open water behind and below the dam, another indication that the hole in the dam was not big. However there was a foot of air between the ice attached to the dam and the water of the pond. I went again the next day and saw evidence that holes that had been made in the ice froze and some scat sank into the snow and some sat high on the dam. I also heard a beaver gnawing in the nearby lodge. So, judging as much from what I learned during subsequent winters, I am almost sure the otter family I saw in October was back under the pond with access to their old dens in the rocks and air to breath between pond water and thick ice above. If recent history was any guide, the otters would keep digging the hole deeper. The U. of Calgary scientists made the same observation: otters trench the dam deeper throughout winter.

Then thanks to a four day flu and our son's hockey tournament I lost track of the otters. When I got back to the pond I saw beaver prints and a gnawed tree on the shore. On February 22 I saw two beavers swimming in the open water behind the dam. They munched on the logs and paid no heed to the flow of water out of the high holes through the dam. Glistening black bodies half out of the dark water surrounded by the silver of compromised ice. Their fore paws clutching small nondescript brown sticks as they gnawed off bark exposing the white of  two magic wands. Dead winter and everything seemed alive.

Even without otters around all beaver dams leak liberally during winter as freezing and thawing loosen the packed mud that holds back the pond water. The ice cover defeats any beaver effort to patch a dam during the winter. Not that a beaver would want to; having some water escape under the ice puts that layer of air between ice and water that even beavers appreciate. 

However, that's all for-ever-thus stuff and doesn't challenge the hydrological-beaver paradigm. A series dams at half capacity still does wonders for the water table and eases downstream flooding.

Meanwhile, as far as I could tell, otters were not in the pond but they were on the island. The next time I saw signs of otters was on March 24. There were slides on the north shore of South Bay and up on the South Bay trail showing how the otters slid down the ridge behind the Narrows. Did the beavers keep them away from the pond? What was clear was that while they were in Otter Hole Pond, unlike in February 1996 and 1997 they did not trench the hole in the dam. Unlike the two previous winters, the snow covered pond was level.

Through the final series of freezing and thawing, the dam began to leak liberally in several places. The water level behind the dam dropped another foot at least. I hazarded walking on the slippery sticks, camcorder running. I heard the leaks but couldn't discern a hole. On March 28, as the rush of water into the pond diminished, I saw beavers patching the hole high up on the dam. By March 31 the pond water was brimming the dam. The thaw holes in the dam were serving a purpose, keeping water from flowing over the top of the dam washing away mud that the beavers were putting there. Hard to describe the great love I felt for the paradigm. On the video tape I kind of ah-shucks it like Gary Cooper: "plenty of water in the pond."

video still of Otter Hole Pond dam

My sketchy observations can't be used to prove anything. The observations of trained wildlife biologists can be sketchy too. The University of Calgary scientists made many of their observations from a Cessna. What gave validity to their study was the number beaver ponds they watched, 97. The conclusion of the University of Calgary scientists was that while all beaver ponds lose water in the winter, when otters are in the ponds there is a greater loss of water and in a more dramatic fashion. So what does it mean when there were otters in the pond and there was not a dramatic loss of water?
An outlier, but in my book it is the stuff of history. And the beavers spent the next winter in Otter Hole Pond too: read on to Chapter Three.

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