Saturday, March 10, 2018

Chapter Six

Why Did Two Beavers Families Leave Their Lodge, or Would You Want an Otter Family Living Next Door During a Long Winter?

Otters in the East Trail Pond

With the freeze fast approaching, the ponds prepared. The vegetation that almost turned the ponds green in the summer shrank under the dark water. Leaves fell, most birds and all insects disappeared. With fall rains the water rose under the dejected air.

Beavers packed mud on the lodges where they planned to spend the winter. The beavers in the New Pond left their new lodge in that pond and just as they did the year before, they moved into the lodge on top of the Beaver Point Pond dam.


Unorthodox, but otters might think twice about putting a hole in the dam. The mated adults of that beaver family had put up with otters since 1996 (see Chapter 1), so I respected every move the beavers made.

The beaver families in the Duck Pond, Shortcut Trail Pond, East Trail Pond and Big Pond prepared for winter in the lodge where they had spent the late summer and fall. But the Lost Swamp Pond beavers, whose lodges an otter family preferred to use, moved out of their pond.

Because of the Duck Pond beavers' confrontation with screeching otters dancing on their lodge, climaxing the last chapter, I spent more time observing that pond. On November 29 two beavers sat on the Duck Pond lodge grooming each other in the late afternoon, just the time the otters fancied grooming.

At the same time a beaver stared at me as it floated in the icy water along the shore. I wrote in my journal "I can't help but think that what brings these beavers out is a campaign to keep otters away from their lodge and pond."

Well, that's perhaps a pointless observation in November. In the late fall before the freeze beavers have to be out in the afternoon. They have branches to collect before the pond freezes at night. (Let's not exaggerate the amount of time they spend cutting and hauling. The typical beaver activity in the late fall is waddling ashore and gnawing the bark of any big tree they had cut down. The best way to prepare for winter is to fatten up.

The Beaver Point Pond beavers dined on a maple trunk. The Duck Pond beavers stripped a huge ash tree trunk.)

We had a rather cold November, below 0F on Thanksgiving Eve, which I thought was a good reason for otters to leave the ponds for the bays and river. Despite having watched otters for only seven years, I had the notion that otter families always left the ponds in November. Seeing the ponds they grew up in freeze at night and thaw during the day must be quite a shock for otter pups. Ice is rare in the river until January and the bays take longer to get thick winter ice than the beaver ponds. So to ease the shock, mother takes them to the bays and river to further perfect their skills without ice getting in the way.

But judging from the scats I continued to see, the otters remained where the beavers weren't, east of Beaver Point Pond dam and into  Lost Swamp Pond. Since the beavers had left the latter pond, I assumed the otters spent most of their time there. So I sat staring at the pond when there was any open water, but saw no otters. Then as I walked down to Beaver Point Pond just below Otter Hole Pond, I saw something frisking in the pool of open water behind the dam where the beavers lived. I forgot all assumptions and expected to see an otter but instead a beaver climbed up on the ice to sniff the air.

He wasn't looking for otters, more likely wondering why the hell I was bothering him at that stressful time.

Then on December 5, I saw the slides of three pups, their mother and her female helper, in snow along the shore of the Lost Swamp Pond.

On their way to South Bay they ducked into Otter Hole Pond, ignored the Beaver Point Pond dam lodge, made a feint toward the Porcupine Hotel and finally explored the New Pond. When the beavers were there that small pond seemed exempted from the fishing the otters did in the fall. Now, because of the leaky dam, there were holes in the ice that the otters couldn't resist.

Thanks to the snow and ice I could clearly see that the lodge beside the Lost Swamp Pond dam had been the otters' headquarters.

There were otter scats on the lodge and on the snow around it. I took those scats and a small hole high up in the dam as tokens that they planned to come back. With thinner ice behind the leak, it would be easier to make a hole through the ice.

That same day I took a photo of the Big Pond beaver lodge but not because of any otter scats around it. That lodge showed the classic profile of how the beavers prepared for winter with mud on top and a cache of bark all but sank in front of the lodge extending 20 feet into the pond. 

Big Pond Lodge in December 2000 (two muskrat mounds along the back edge of the pond)

The beavers' efforts to keep water open around the lodge made the ice there gray. I saw a beaver stick its head up in the pool of open water just before I took the photo.

So why bully beavers out of a pond? Shouldn't the open water in front of the Big Pond lodge be more attractive to otters than the ice, already probably five inches thick, around the Lost Swamp Pond's lodges? On December 12 I was able to ski around the pond perimeter and absolutely saw no signs of beavers.

Life takes odd turns. In the late summer of 1992 the Lost Swamp Pond was my just discovered beaver-made Paradise for which in anticipation of symphonies to come I moved to the island see Introduction Continued. In December 2000 all was quiet save for water flowing through the otters' hole in the dam. The beavers left our Paradise. 

Were they driven out by the otters? As I tried to explain in my Introduction, thanks to 400 years of trapping, beavers and otters were strangers in their own land and strangers to each other. Working out a way to share the beaver ponds took time.

I knew that the otters had bugged the beavers in the Lost Swamp Pond. In the fall of 1998 I saw the otters move into the lodge behind the dam, despite the tail slapping protests of the beavers then using that lodge. The beavers moved to the lodge beside the dam. I heard otters screech as they scatted on it. Telling the beavers off, I thought. During the warm January in 2000 I saw beavers in the open water, but not eating. Were they on the look out for otters? Then later that year when Otter Hole Pond was too shallow thanks to the beavers' neglect, an otter family made the Lost Swamp Pond lodges their preferred dens.

From the beavers' point of view, the trouble with otter families is that bigger families get bigger still. A mother with two pups can manage by herself. In 1999 I needed binoculars to see if they were sleeping on a lodge. A mother with three pups gets help from sisters or past daughters now adults. In 2000 the mass of otters on top was almost as big as the lodge below. 


And too many otters were especially troublesome in the Lost Swamp Pond even though it was the biggest pond in the western swamps of the island.

The geography of the Lost Swamp Pond caused the crisis. The dam flooded a gully about 50 yards long. The beavers built a lodge at the top of the slope where the creek drained into the gully. All the pond behind that lodge, about 200 yards long, was shallow with a network of pools and channels dug over the years by beavers and muskrats. Their other lodge was at the east end of the dam on the precipice of the steeper side of the gully. To the east of that lodge was another shallow network about 50 yards long. 

The two Lost Swamp Pond lodges during the drought of 2012

Between the two lodges and behind the dam there was a deep pool of water probably six feet deep on average, at least 3 feet deep even with a deep hole in the dam. In all the ponds I watched, there were no two lodges arranged to make it so easy to get from one lodge to the other quickly and quietly. Beavers would not be comfortable in one lodge if otters were in the other, especially during the winter. Beavers usually take a very long nap during the first cold weeks of winter, a well deserved rest for all their fall labors. Do they want otters barging in? So in the fall of 2000, the beavers left the pond.

But I had to wait for the otters to return and figure out where the beavers went before I could make more sense of this possible new chapter in beaver-otter relations. If the otters didn't come back to the pond, why blame them for driving the beavers out? And if the beavers wound up in a better Paradise, more power to them. 

Meanwhile I was distracted. Otters delighted me by showing up in the river. On the morning of December 9 otters paid their respects to little Goose Island in front of our house. They came up on a snow covered rock that faced the main channel of the St. Lawrence River.

We also saw otter slides, tracks, scats and fish remains a half mile around the headland on the ice along the Narrows between Wellesley and Murray Islands.

But it was a very cold early December. The bays iced over. Some otters returned to the ponds. I saw scats and slides of two otters at the Big Pond dam on December 18. 

I didn't see otter tracks anywhere else and I make that claim with confidence. Once we had enough snow, I toured the valleys on skis. I could go anywhere flat and up any ridge not too steep. After crossing the golf course behind out house and getting up a wooded ridge, I skied down a vernal creek through a rocky porcupine haven that got me into the woods south of Big Pond. I made a ski trail through the trees, mostly red oaks and hickory and a few 150 year old oaks that used to shade the Ayrshire cattle. That trail brought me out at the midpoint of the pond.

 the Big Pond late winter taken from the dam (I could no longer ski over it)

I could ski past the beaver lodge on the north shore of the pond on my way to the surveyor's trail that led straight through more woods to the Lost Swamp Pond. 

 otter slides cross my ski tracks (Lost Swamp Pond 2003)

Then I had an easy ski over three large beaver ponds, Second Swamp, Otter Hole and Beaver Point Ponds, and down over the New Pond to the back of South Bay,

a big chunk of my easy ski, from Second Swamp Pond dam looking up toward Lost Swamp Pond dam
or after skiing down the Second Swamp, I veered to the right and up to the East Trail Pond. Then it was a easy ski over Thicket, Meander and Shortcut Trail Ponds 

otter trail going from Shortcut Trail Pond up to Thicket Pond
all the way to the Duck Pond which put me half way up the north shore of South Bay. (Easy as both routes were, by the end I appreciated simply skiing across the bay and through Thousand Island Park to home.)

My winter route took me to the Big Pond first almost every day and as luck would have it, I entered the pond just where the beavers decided to buck the take-a-long-nap-at-the-beginning-of-winter tradition. On December 16 as I skied out of the woods aiming to angle across the mid-section of the pond and check the beaver lodge on the north shore, I saw a beaver on a fresh trail in the snow obviously made by beavers bringing branches down to the south shore of the frozen pond. 

The beaver retreated as I noiselessly moved on my skis. He stopped next to a hole in the ice and began munching on sticks. I tried to ski around him but he dived into a hole in the ice. 

I angled back toward the pond and heard beavers mewing from under the snow. I recalled that there was an old lodge there. I didn't take a photo of it because there was nothing to see. The typical muskrat mound cut more of a profile.

So what were the beavers doing on the south shore 75 yards from their classic Beaver Lodge Ready for Winter on the north shore? On the 20th I stood by that lodge and heard beavers humming inside. On the 21st I heard "at least" two beavers gnawing in the hole on the south shore and heard "two or three" beavers swimming under the ice nearby.

My first explanation for the evident plethora of beavers in the Big Pond was that the Lost Swamp Pond beavers moved into the old lodge on the south shore. Invading another family's domain is not what beavers are supposed but I had gotten used to strange things happening in the winter.

I always assume beavers' plan ahead and move to improve their situation. So: it was easy for them to open the ice on the south shore because of a spring there a few yards from the old lodge.

the south shore spring in January 2003 marked by a pipe put there back when the valley served as a pasture

With the thaw in March I could see the channel going from the spring passing the old lodge and curving toward the main channel.

the old collapsed lodge on the back left edge of the photo was convenient to water from a spring flowing from where I was standing to take the photo

But I was also impressed by how difficult it would be to commute from the lodge on the north shore. It wasn't a straight shot in a deep pond like going between the two Lost Swamp Pond lodges. Plus there was a more copious spring on the north shore 20 yards east of the new lodge. Indeed the beavers used it the previous winter. And that spring was close to woods along the north shore.

But forget geography, the two lodges in the Big Pond were not at all equivalent. I became somewhat of an expert on the viability of beaver lodges. I am too stout to get inside one but I knew where to find abandoned lodges suitable for my son and others to explore. 

There has to be holes in the top of the lodge so you can see. The tunnels to the lodge, once under water, have to be bone dry, relatively straight, and the crisscrossing timbers above it can't be rotten or you get a dirt shampoo if not worse. 

Peaking into lodges I've never seen the lower drying chamber or the upper chamber cluttered or fouled with anything. The lattice work making the tunnels to the chamber and its roof give way to smooth floors curiously inviting just as dirt flattened by a thousand and one nights of soft fur should be. (Beavers sleep on their backs.) But without upkeep by beavers, after three years the lattice work of logs begins to rot and collapse.

I wasn't then and still don't know why the beavers left their perfect lodge for a flattened heap of logs with no cache next to it. Since in this history I am focusing on the relations between beavers and otters to best elucidate the history of the habitat I loved, I will make the case that otters had something to do with it. 

But before doing that let me confess that the beavers' ill-considered move was great for me. They had to forage in the nearby woods almost every day in order to survive. To make a wonderfully long story short ( a long story is just what you need in winter) insatiable curiosity about the beavers kept me going out every day I could. The groups I took out to see what the otters did also had to stare down at the beavers' hole.

Standing 10 yards away I got good close-ups with the camcorder. Although they were rather wide eyed for animals who should have lowered their metabolism to survive the long winter, all the beavers' motions were slow. Forget nibbling, here were the seamless embraces of the connoisseurs of brown bark, stripping and dropping wee cream colored sticks in the milky ice water and pristine snow.

When it was very cold, I looked into the hole they fashioned and saw the nose, whiskers and hot breath of a beaver. Looking down on their clandestine comfort I had to wonder who was fooling who.

But with my next step they ducked into the brown water and swam back to the flattened lodge that I couldn't fathom. 

I saw them range the woods for likely trees and I tried to buck myself up for a scientific study: how far did they range, what trees did they prefer, what was the heaviest logs hauled, how much bark did they gnaw in place? But without leaves on them I couldn't identify the trees, often saplings with protean bark. Except when fleeing me, the beavers never walked a straight line. We can only make sense of shoppers at a Mall by what happens at the cash register. Beavers who eat where they cut and also haul branches away are more complex. But what dumb simple pleasure I got when I saw them rear up in the deep snow and cut down a tree.

Then the beaver dragged branches past standing trees that looked exactly like the one he cut down but closer to the hole in the ice. 

After pausing to watch them I pressed on and the beaver lodge on the north shore of the pond that was right in the way. That soon presented another piece of the puzzle.

In the winter there is a way to tell if beavers are in a lodge other than listening for humming and gnawing inside the lodge. There is almost always a small vent hole on top of the lodge frosted by the animals' hot breath below. (The old lodge on the south shore that had not been packed with mud was an exception.)

I heard beaver noises in the lodge until January 5. Then nothing, yet I saw a large vent hole on top of the lodge often frosted throughout the rest of January and half of February. That justifies me in asking: were otters sleeping in the lodge and did they prompt the beavers to relocate to the south shore?

On December 18, I saw the tracks of two otters at the Big Pond dam. On December 20 I heard a gush of water through the small dam above the Big Pond. The two otters who had just moved in probably dug a hole through the dam. Doing so would ease their way as they fished under the ice of the three small ponds up creek from the Big Pond.
Yes, the beavers appeared on the south shore on the 16th, two days before I saw the otter slides. But I didn't see slides coming into the pond which likely means the otters moved into the pond before the 18th.

It goes too far to accuse winter of having a sense of humor, but there is irony under a frozen pond. The beavers who built the pond, dug its channels and extended its reach with canals seem quite constrained when it freezes, hence the paradigm with a snug lodge and a store of winter food right next to it. 

Otters wire a series of ponds in the winter, especially a still growing family. I soon saw how they do it. The otter family moved back to the ponds on December 28, twenty-two days after they left. The irrepressible family showed me how otters can cut a swath in the winter, but one that is mindful of beavers. 

Since beavers don't stray far from their pond, on my winter tours of the ponds, I tried to think like an otter. That made it easier to sense that while the beavers didn't react to the otters, in most of the ponds the otters did adjust to the beavers being there. 

Back tracking the trails the otters made on December 28, I saw that they slid down from the west from the ridge forming the Narrows, and scooted around the Duck Pond. They went up on the lodge and then went to the bench on the nearest shore, their old latrine, but left no calling cards there this time. Then they bounded up the chain of ponds too small to bother with and up and over the Shortcut Trail Pond dam. They checked the two beaver lodges there, dug into the one closest to the dam, then stopped without getting in. Were they deterred by a beaver grunt? Then they took the shortest route over beaver-less Meander Pond and over the ridge to the New Pond.

how otters get over a log

I got the impression that they denned in the Porcupine Hotel and didn't go under the ice except behind Beaver Point Pond dam. 

However they stayed away from the lodge and went directly up to Otter Hole Pond dam. They probably denned there or in the abandoned lodge just behind it. I came out the next morning and saw tracks going from the dam up to the East Trail Pond.

Up at that pond, the beavers lived in a lodge right beside the dam. Still the otters skirted the dam, climbed over the lodge where the beavers were, and nosed around the large rock I hid behind when I saw them there in October. Then they bee-lined to a lodge in the middle of the pond, 

just after otters checked the East Trail Pond lodge in January 2003

nosed around it, and then, with a few zig-zags, made their way to a small lodge on the other side of the creek that came down from nearby Shangri-la Pond. The beavers only used that lodge in the spring. 

The otters didn't stop there. Their slides led me to a hole in the ice, right next to the cliff that divides the upper East Trail Pond from Shangri-la Pond. All around a hole through the ice that they probably dug themselves was an array of scats.

The north shore of that section of the pond was a granite cliff that probably reflected enough sunlight to keep the ice along it relatively thin.

Then the tracks led across the pond where there was another hole with tracks all over, but no scats. And that appeared to be the end of the story. I later saw that there was a remnant of a bank lodge there.

The moral of the story is that otters are from Missouri: show me! In October 1997 I fancied that beavers confronted otters and negotiated terms for use of Otter Hole Pond that forbade otters from using the beaver lodge. The next day, the mother checked the lodge to see if the beavers were in it. 

So in December 2000 the otters checked the lodges where just weeks before they knew beavers slept. And remember that otter pups were still being schooled. The mother had to remind them that as they string the ponds together on top of the ice, find holes, and then find fish under the ice, to never forget: when entering a beaver pond cherchez les castors.

That's probably best done by sniffing the lodge. When swimming down an under ice channel honing its senses for fish, an otter would probably prefer not to bump into a beaver.

two views of the world under the ice

But let me add a caveat which I observed that winter. Whether beavers are in a pond is of far less concern to otters than whether other otters are in the pond.

On December 31, during a gentle snow storm I tracked an otter from the Lost Swamp Pond down to Otter Hole Pond. (No sign that it spent time in the Lost Swamp Pond.) On January 7 I followed an otter's trail from Otter Hole Pond to the East Trail Pond dam and there I saw a hole and several slides at the west end of the dam, and slides behind the dam going to a hole near the beaver lodge. There were what I described as "long brown slides" meaning that otters had been under the ice in the mud. One slide left the pond. 

It struck me that perhaps the four otters in the upper end of the pond discovered the intruder when they fished under the ice behind the dam. That led to all the scurrying about, and the intruder thought it best to leave. 

The beavers didn't get involved, no signs of them stirring since the pond froze. (They came out on to forage for bark on January 17.) But the otters who remained in the pond didn't move next to the dam where there was likely an old den in the pile of granite east of the dam. That was too close to the beavers. There was only one scat on the ice outside a hole behind the west end of the dam where another touring otter was likely to approach the pond. After all the to-do, the otters still slept up pond. Outside a hole in the middle of the pond there was a fresh array of the usual scats. 

That was not their original den. There was a small hole in the dam and water had probably drained away from the otters' first den in the upper pond. So they moved down pond but still at a respectful distance from the beavers.

I could use the Big Pond as another example of the otters' respect for beavers. The otters first scatted and probably denned at the dam, far from the beaver lodge up pond. 

But if the otters were so respectful then how can I suggest that the beavers moved from one side of the pond to the other because of the otters?

Geography might have influenced the beavers' decision. The beavers' north shore lodge was relatively close to the main channel under the ice, the old creek. As they swam up pond looking for fish the otters swam by the winter cache extending from the lodge. But if the otters used the lodge so conveniently situated as a place to rest after bouts of fishing, why didn't I see otter scats around the lodge? 

That lack of scat explains why at the time I didn't think the otters were lording under the pond. After checking on the beavers in the Big Pond, I skied through the woods to the Lost Swamp Pond and saw how otters can do a number on a beaver pond. Beginning January 11 every time I went I to the Lost Swamp Pond  I saw fresh tracks and scats on the snow.
The otters seemed to run wild and judging from their scats were well fed. That raises the question: why didn't the otters go directly to the Lost Swamp Pond where they had occupied the beavers' last active lodge and presumably knew that the beavers had moved elsewhere?

In all the annals of the Struggle Against Nature little is written about water's struggle against ice. A flash freeze leaves waves suspended in air above the river; a cold night turns drips into pendants dazzling the sunlight. Cold destroys the very nature of water, just ask a frog frozen in the pond ice. Water finds an ally in snow, that amorphous state between ice and water. During a cold winter snow is a heat wave. Snow melts at the bottom softening ice. Simply put the otter mother waited for snow to pile up and do half the work of opening holes in the Lost Swamp Pond ice. After all there were no beavers there to do it and no beavers swimming under the ice waking water up softening the underbelly of the ice.

When the family moved to the Lost Swamp Pond. I thought conditions perfect for them. On New Year's Eve we had snow, then bitter cold, and then 32F. Snow melts from below mollifying the ice. There was another round of snow, bitter cold and 32F and then the otters moved.

How to describe the silly joy of coming out of the snowy woods facing a trackless white expanse and knowing just where to ski over to see an arc of slides in the snow funneling into a hole. That's the way otters hang out a Home Sweet Home sign. Add the joy of sometimes tracking their forays -- literally four rays that winter. I got the impression that the mother challenged her pups to hone the technique of scooting around a pond looking for weak spots in the ice suitable for opening a hole. Freezing and thawing creates gaps along the rocky shore and around the trunks of dead trees in the pond.

I saw prints and tail slides etched in the ice which gives them the aura of profound significance, like evidence from prehistoric times. Having seen how fast otters go around a pond, I knew their whole dance may have lasted no longer than a few minutes.

I found my Winter Paradise.

After a week exploring and, judging by scats seen outside holes, making temporary dens in various corners of the pond, the otters began to trench the small hole in the dam that they had made in December and they dug another hole in the dam. Half of the dam was on private property and in April 1996 the land owner dug a three foot long trench in the dam. But he dug down from the top of the dam. Otters dig through the dam and then trench it down. I was always able to walk on the dams over their trench, and otters could sit up there to keep an eye out for fish. Plus otters always dug their holes on State lands.

I knew that I first heard the water gushing through the dam not long after the otters did their trenching because I saw that the stream of water on the ice below had not gone far down the Second Valley.

I could also catch of the odor of sulfur dioxide from the water that had been cheated of oxygen since the ice cover. The otters kept trenching the hole deeper in the dam and by mid-January, looking from below the 6 foot high dam, water poured out of a hole half way down it.

Lost Swamp Pond dam leak on January 24

With collapse of the ice, again judging by their scats, the otters made the lodge by the dam their headquarters once again. Nick of time: with the ice collapsing the lodge looked like a flying saucer about to take off.

As the water drains out of the pond, otters can disappear under a pond. But the otter family was out so often I was sure they were planning to leave. They stayed for 31 days. They were so steady I took four groups of people to show them why otters put holes in beaver dams. 

Thanks to my patrolling every corner of the pond (easy when I was on skis) to make sure the otters hadn't left, I finally found where the beavers moved. They built a huge lodge in what must have been the long abandoned and much smaller pond above the Lost Swamp Pond, where beavers lived before they created the huge pond.

When I discovered the beavers' refuge, I also saw otter tracks below holes in the pond below the small dam. The beavers didn't escape the otters. I saw scats on the beavers' new lodge. There were also two round holes in the dam which effectively drained most of the pond. 

Still, the beavers seemed quite content in their new home. I heard beavers humming in the huge lodge, continued to see stripped sticks around it, and with the thaw saw that the beavers cannibalized much of their lodge. Their winter cache was as much on and in the lodge as it was in the deep pool of water around the lodge, which I took as token that they planned to move back to their old lodges as soon as possible.

Discovering that refuge was a relief. If I had to blame otters' moving in for the beavers' moving out of the pond then at least they did not go far and could easily move back. Seeing more otters in the pond made the history that entranced me. (The State of New York was still publishing maps showing that there were no otters in the St. Lawrence River.) But I knew only the presence of beavers saved the ponds from a Decline and Fall. 

So, do I have to blame the otters for driving the beavers out? Am I over interpreting what I saw, making too big a deal of accidental instinctual reactions of the animals to each other? In monographs describing the behavior of beavers you usually find nothing about otters. 

The Lost Swamp Pond beavers' move in the fall of 2000 was not like the Otter Hole Pond beavers moving down to Beaver Point and the New Pond, nor was it like the First Valley beavers moving from the Lowest Pond back to the Big Pond. The Lost Swamp Pond family revived the meadowed remains of an old pond which situated them farther from shrubs and trees. The Otter Hole Pond family flooded trees creating new beaver habitat. In regards to the beaver-otter rivalry I can only argue that making the move made it easier to raise kits without otters around. (See Chapter 5.) The First Valley beavers returned to a pond surrounded by three patches of woods that they would harvest for another ten years. Beavers never revivified the meadow above the Lost Swamp Pond again. Beavers still remain in the Lost Swamp Pond as I write this in 2018, although they haven't flourished there since 2010.

In 2001 the beavers moved back to lodge beside the Lost Swamp Pond dam as soon as they could in early April (that was a long winter.) By that time, as far as I could tell, all the otters had left the ponds for the river. Except, I hoped, the mother otter about to give birth to a new litter of pups. But I knew the wide open Lost Swamp Pond was the least likely place for her to be staying.

Given that I thought the Lost Swamp Pond was Paradise, I was sure the beavers would adjust to the otter problem and stay, but I had to wait until next winter to see how that would play out.

Meanwhile throughout the winter the otters that I supposed were in the Big Pond did almost nothing as far as I could see. Two adult otters don't advertise their presence in a frozen pond the way a family of otters does, but I knew the otters were active.

On January 11 I saw an otter slide at the upper dam and two slides at the lower dam. On the 20th I saw slides at the upper dam and the vent atop the lodge was moist. Then snow covered the vent. But a few days later the vent "melted open." I usually heard no noises from inside the lodge save one day when I heard something swim away under the ice. In mid-February I saw otter slides and scats by the upper and lower dams and around the beavers' hole on the south shore.

I build my case that the beavers in the Lost Swamp Pond moved out because of the otters on how I saw the animals react to each. I had never seen them react to each other in the Big Pond nor in the small ponds between it and South Bay. Nor can I argue that the Big Pond beavers needed time to adjust to the otters. In the fall of 1994 I chased five otters from the Lowest Pond to the Big Pond and saw otters in the Big Pond.

In January 1996 otters moved into one of the lodges the beavers built between the Big Pond and South Bay. I called it Pine Tree lodge since it was built around a pine tree in a rather small narrow pond.  It was just above the Lowest Pond that first pond I observed in the winter of 94-95 that showed me that all winters don't go by the book. 

Did the otters using Pine Tree lodge prompt the beavers to abandon those lower ponds? That winter the beavers lived in a bank lodge in the small pond below the Big Pond dam, right in the otters' way. 

In November I saw that the otters were living in that lodge and the beavers built their new lodge on the north shore of the Big Pond, the lodge they abandoned in December 2000. 

I wasn't a good enough tracker especially back in the 1990s to analyze and assess the effects of otter demographics. But I did track the otters from the Pine Tree lodge over to Otter Hole Pond where they began digging a hole into the dam there. I can argue that once they discovered the virtues of Otter Hole Pond and the Second Valley, the Big Pond and the First Valley became back water for otters. Then in 2000 the otter population using the ponds doubled if not tripled forcing the Big Pond beavers to put up with otters again. Add to that the beaver population was booming too.

That said, in March as the long thaw began, the beavers seemed in a hurry to return to the lodge on the north shore even though they had improved living conditions on the south shore. They dug into the bank behind the old lodge. Beavers can gnaw through ice so they can burrow into frozen dirt. To defeat the water in their holes freezing at night, they dug a hole coming out of the burrow onto their path to the woods. That struck me when I saw an adult beaver pushing a branch down the hole even though there was open water just below where we were both standing. He wanted the convenience of having food without having to deal with ice that night. 

But recall the paradigm: coming down from a high and dry chamber in the lodge, swimming under the ice, and fetching one of the logs sank in the pond beside the lodge. That's the comfort they returned to in early March. They finally dined off their winter cache which gave me the impression that their move and return was a well thought out plan to maximize their food consumption and forget lowering their metabolism and the paradigm.

I also discovered that when beavers upscale they don't turn their backs on burrows. When they moved back to the north shore lodge I saw a beaver disappear down a hole 15 yards from the lodge. Investigating I saw that they had a channel from the lodge to the burrow that tunneled back and breaking out about 5 yards from the usual shore of the pond. I also saw old otter scats around the hole. Then I saw sticks and dirt pushed into the hole, presumably by a beaver. To keep an otter out?

a nine year old makes it through a beaver burrow in good shape

But that was an old scat. The otters were long gone. After the thaw the beavers repaired the dams and despite a spring drought the ponds filled enough to settle my nerves.

But maybe not the beavers'. 

In spring I expected that if I saw an otter it would be brief and fleeting and maybe give me a glimpse of the mother of the future family that would engross me that fall. I assumed that otter females were off caring for pups and the males were mainly in the river though occasionally marking their territory. 

I saw fresh scats on the Big Pond dam on May 15 and May 31, which I took for evidence that for two weeks the otter was elsewhere. On June 2 as I walked on the dam, a beaver came out of the grasses in the pond and simply floated in the water below me. I didn't suspect it was watching for otters.

Beavers might not mind leaving the lodge during the day while nursing kits were the center of attention. I had observed beavers scarfing up pollen floating on the pond and that spring the Big Pond beavers seemed more attentive to their dam periodically pushing up waves of mud. 
mud on Big Pond dam imprinted by an otter's tail

Doing either would seem to me, if I were a beaver, more pleasurable in the bright sun.

On June 5 I walked up the creek from South Bay to the Big Pond, I thought I saw a fresh trail in the grasses. I had seen geese parading goslings there but this trail seemed more eager so I hoped it was made by an otter. I knew a scat on the dam might tell the tale. On the dam I saw otter prints in mud that a beaver had pushed up. I also saw a lone beaver behind the north end of the dam floating aimlessly. Then I heard a noise below me and saw an otter cruising up the creek headed right toward me.

When it got to a fan of cattails below me it veered off but still came up and over the dam, swam into the pond, started periscoping up and snorting at me. With absolutely no cover I simply stood there camcorder running and responded to his snorts with civilized banter. After a minute of that I looked up from the lens to see what the beaver made of us and I saw it swimming toward the otter.

The otter forgot about me and the two animals warily eyed each other closing the distance between them. Then the otter turned and the beaver followed despite the otter's rearing back and screeching. The beaver was relentless. 

The otter swam faster still looking back but not screeching and then swam away underwater. It surfaced closer to the north shore, looked back at the beavers, dived again and I assume swam up pond. This link opens another tab with an edited but still almost 6 minute long video of the encounter.

Over the years I had learned that tracking is not a one day affair. You can learn much about what you saw today from what you see tomorrow. But what can you learn months later?

The beaver wasn't protecting the lodge where kits were likely being nursed. The beaver engaged the otter behind the dam and sent it on a course up pond toward the lodge. In the video, you can barely see the lodge way up pond. 

So how can I say that this encounter in June has any bearing on whether otters prompted beavers to leave their lodge back in December and January? In the winter the beavers were out of sorts and the otters were in control. In June the otter was screeching and the  cool and collected beaver didn't even slap its tail. 

But if under ice geography gave all the advantages to the more agile, more awake otter, then this is exactly what we might expect to see in June. As the otter tried to go about its business, the beaver exacted what revenge it could for the indignities suffered during the winter. This is my pond. Go away.

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