Favorite Tree – The Trail, The Blood, and The Fisher

So, here’s something both new and unexpected—I now have a favorite tree species. Crazy. I (the royal “I”) have played favorites with many individual trees over the years but having a species that I call my favorite is new for me. Playing favorites makes me a human, or so I’m told.

Don’t get me wrong, I’ve always appreciated trees. But beyond the old, the magnificent, the gnarly, and the climbable, trees have always just been part of the landscape to a certain extent. They are where owls perch, what fall across my trails, and what feed Boletes, Chanterelles, Amanitas and a gagillion other fungus species. I definitely tend to favor fungus and am not ashamed at all… makes me human.

The lessons kept rolling in, regardless of my skepticism towards seasonal reality (which differs from a perfect world where winter never stops and  there is peace on earth… not necessarily in that order).”

After 50 years I finally have a favorite tree. Maybe it’s been a long time comin’ (more like “didn’t see it comin’”). It’s a long story and for that reason I left out excessive details—you’re welcome. I’ll mention that selecting a favorite tree species is an event directly tied to NASTA (if you remember, that’s the calendar I created in my last Nature Bummin’ column) and my frustration with the non-linear transitions of the seasons.

The lessons kept rolling in of course, regardless of my skepticism towards seasonal reality (contrasted to a perfect world where winter never stops and where there is peace on earth… not necessarily in that order). As it turns out my appreciation for one particular species of tree grew through these timely lessons, and my fondness grew for one particular phase of this particular type of trees’ life. And so here it is—drum roll please! Big-tooth Aspen (Populus grandidentata), is now officially my favorite tree! Especially ones that are dying. Dead ones are cool too. More on that later…

Where were we?

That’s right, we were talking Mustelids—the weasels, as they say. We all love them—from the sight of the overly adored sea otters along the eastern shores of the North Pacific to belly slides and bounds left in winter snows by local Maine river otters. Weasels can be so sweet and cute that it’s easy to forget they are also vicious killers, which is 100% fact, based on all data ever known. But this is not a column about Mustelids and how they cope with an impressively high metabolism (they eat like crazy). No, this is about Mustelids in spring in Midcoast Maine. More of an album title than a song. Still has a nice ring to it. But I digress.

Getting back up to speed—way back in early March 2021 we had found an active, elevated Fisher den in a cavity about 20 feet up in a Big-tooth Aspen out back of our house. Through tracking and game camera documentation we deduced that the mustelid inhabitant was a female.  The stage was set for learning—we allowed ourselves to dream of tracking the fishers all spring, to find sign of breeding and offspring behavior, and to follow and learn from this imaginative family of fishers living in the neighborhood. We weren’t asking for too much, were we?

In the end, we ended up with squat. The snows abated early, and the game camera went untriggered. From where I stood the trail went cold, and with the multitude of other nature distractions the fisher scene was forgotten until winter 2022 rolled around… and February was fantastic tracking.

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Fisher trail

We marched into March 2022 with high hopes of fisher mating, courtship, and family tracking, but the month came with little to no snow. In fact, with spring arriving way before its time (what part of March 20th does mother nature not understand?) conditions were so bad for tracking that my attitude towards the true harbingers of spring grew more and more jaded as they began to show up.

It’s not the woodcock’s fault it was able to show up early in the month (March 4th), and it’s understood that amphibians will migrate the first chance they get (this year March 19th). But I wanted to learn about fishers in March (it’s all about me, isn’t it?) And so, these events I’ve celebrated for decades left a sour taste in my mouth. “Please give me one more dusting of snow for direction,” I begged to no one. No one ever wants to hear that winter is too short.

“And that was when a neighbor called to let me know that there were two fishers in her yard, and one was in a tree.”

I was losing time—my current 100-year plan is to live to 150, so that means I only have 100 more winters left to enjoy and learn from (New Jersey mathematics education). Sounds like a lot? Glacially speaking 100 years is merely a pittance, so internal pressure to be “one with winter” grows every year, along with ever-increasing dread that with each day the current winter is closer to being over. And what suffers most from this illogical and unnecessary stress? Nothing really, in the end we roll with it—but not without a fuss.

And that was when a neighbor called to let me know that there were two fishers in her yard, and one was in a tree. I was there quicker than I can write this column, but that’s not saying much at all. It’s already taking too long and is too long… ugh!

Big Fisher in my Backyard

I was there in a minute or less (Jersey time)—because when a fisher is in a tree there is no time to dilly-dally. And sure enough there was a fisher in a tree—my neighbors don’t lie (at least not in this case). It was not too far up—15 feet maybe? It was magnificent and clearly aware of our presence in the yard—mine and my neighbor’s grown son. Aware of us—more like tolerating us I would say—the fisher, lying on the small Balsam Fir branches, appeared to be dozing. I was informed that a second fisher had run off to the north and not too long before I arrived. Two fishers in a yard during the day = excitement!

Things happened quickly

It wasn’t too long before this sleepy fisher sat up, and made some guttural noises in the direction the second fisher had run off to. Its attentiveness and focus was to the North, as if he heard or smelled something.

And with that the fisher slowly made its way down the tree, pausing every so often to make sure the coast was clear (which it was every time). It was on those pauses that I was able to get a picture or two. It was obvious that we were not a threat, and I even started looking for escape routes if it came at us. “Where should I run?” is not a thought that comes up often for me. It was kind of refreshing; I was in this fisher’s world now. Of course it didn’t attack or even motion towards us, just simply ran off after the second fisher. Watching it run off also showed me that if the fisher did come at me there was no way I was running faster than it. Would have been doomed, but what a story that would make!

“Two fishers together during the day in March could only mean one thing, and that was mating.”

For this observer, it was more of a photography session than observing the natural behavior of a fisher—other than watching it climbing down and running off. But you know what I mean. Anyway, I felt like I was a photographer for the first time I can remember in my life. The impact had already happened—I was told that the neighbor’s dog had put the fisher in the tree—and I was benefiting from that impact photography wise. Wasn’t the first time, undoubtedly not the last.

From impact to the…

The fisher coming down the tree and running off did not mean the lesson was over for that morning (are they ever over?) Two fishers together during the day in March could only mean one thing, and that was mating.  Or fighting maybe. Okay—one of two things. It was time to track.

Most of the ground was bare—because it was March 14th–but there had been a dusting of snow two days before, and miraculously, some residual snow refused to melt on icy patches in the woods. Even more luck—the patchy snow that was in the woods was conveniently placed so back tracking the route the fishers took to the field was kinda easy.

The pair most likely roamed the snowless woods together throughout the night and the tracks in the snow told of close interactions before reaching the field.

The pair most likely roamed the snowless woods together throughout the night and the tracks in the snow told of close interactions before reaching the field. There was one interesting stretch where the two lined up and did a shuffle step pattern I hadn’t yet seen in any past fisher trails over the last seven winters of tracking. The trail led to an old stump—fishers love to scent mark old stumps. So, were these tracks laid during courtship and scent marking? Sure looked like it! For some reason I picture a lot of “sniffing” going on at this point.  

After the shuffle step stretch the two separated, but never too far from each other. I followed one trail and looked for blood (always looking for blood), and sure enough found a drip in the snow—one drop every few steps. What’s up with the blood you ask? Sign of estrus of course!

Estrus story magic

In mid-coast Maine female fishers go into estrus (what is referred to as going into heat for canines or dogs for the layman) in early March after giving birth to a litter of 1-4 kits (fisherettes). Around 8-10 days after birthing she is receptive to mating and can only become impregnated during this short window of time. Things happen fast (they have to), and scent marking becomes furious as she announces her mating intentions to the world. She uses what she has at her disposal—urine, anal glands, somewhat nasty fur that’s rolled in whatever, and blood of course.

I call this blood estrus (not very creative) and have been fortunate to have crossed paths with this mustelid bodily fluid on three other occasions—all in snow. Once while tracking a pair of Mink on Lane’s Island Preserve on Vinalhaven that had mated the night before (all over the island if I may add). Estrus drips were scattered throughout the rolling and tumbling track and trail evidence.

A few years later on Lane’s, I was following a bounding Mink trail for some distance when suddenly there was a flow of blood, then another, and then another. Splashes rather than drips, the mink didn’t miss a beat—marking as it bounded. The message seemed loud and clear.

The third time was right in the Marsh behind my house, a female river otter we called ‘Larry’ swam to the shoreline and laid down a 6×6 blanket of estrus in snow right on our property! That was when we learned Larry was a female. All three estrus sightings were found in mid-March snows, and all were photo documented, which leads me to a very insignificant tangent…

Begin tangent: I am not a listing kind of observer. I don’t check stuff off a list or go searching for target species—which pretty much means I have forgotten more than anyone with a pencil might know. A dull pencil is better than the sharpest memory, or something like that. Anyway, I now have photos of three different mustelid estruses (estri?) frozen in snow. This is a list I can get behind. Not trying to get ahead of myself, but I think my next target estrus will be Ermine, short-tailed weasel. Wouldn’t that be something to have photos of 4 different mustelid estruses? I think the answer is “yes, that would be something.” Tangent over

Suddenly we had confirmation. Between the trail, the blood and the fisher itself my dream was coming true—the lessons were right there! Already we had more than the squat we saw the year before so my smile was huge. But the lessons didn’t end there.  Do they really ever end?

Later that week…

I ran into my neighbor’s son, and he nonchalantly mentioned his dog had treed the fisher three more days in a row. Ex-squeeze me? The questions arose immediately! A) How did he not let me know? and 2) How could he let his dog tree the fisher over and over again? Well, the answers were quite simple—A) he was letting me know right now in this moment And 2) The field belongs to the dog. Every day, multiple times a day, for years, that dog has run that field—it’s his! The fisher was the visitor in these regards (at least in the daytime), but it was an important lesson all the same (as opposed to those non-important lessons). What would make a fisher come back to the same spot and be repeatedly treed by a dog, day after day? Gotta be the estrus!

I looked up at the only Big-tooth Aspen in the area and saw the wide open cavity, whose entrance was full of scratches and well-worn bark.

And so, I went to go poke around a little, but where to start without any snow? Old stumps are good, but really we are talking beyond scent marking. There was a female fisher somewhere close by, maybe with a cavity full of little ones. Cavities! That’s it—and that’s when I looked up at the only Big-tooth Aspen in the area and saw the wide open cavity, whose entrance was full of scratches and well-worn bark. There’s been a lot of recent activity there, and it was then in that moment that I realized I love Big-tooth Aspens (BTA), well, at least the ones with cavities.


Big-tooth Aspen

More than just cavities

I love the BTAs cavities, but I also am fond of their bases. Like literally the bottom of the Aspen tree before it goes subterranean. I ventured over to the tree base and there were eight to ten fisher scats scattered around it. Things were getting exciting.

Now, in my humble scatology experience, otters and mink scat/spraint all the time and never have a shortage. You can even find their scat in human trails and in such large amounts that you can’t help but find yourself saying, “this is impressive!” Fisher on the other hand, are more selective with where they go—so psychologically their scats seem to have more meaning, maybe more purpose? That doesn’t sound right. In my experience they are stingier with their scat, probably because they have less of it than otters and mink (I tend to find way less), and thus its significance feels greater. Here I go again—judging scat.

Things were getting exciting.

Anyway, I don’t find Fisher scat too often, but when I do it’s likely to be at the base of a BTA. And here it was, recent scat, active cavity in a tree, estrus blood, and a repeatedly seen fisher and a female living in the area. I started to look at the world a little different at this point.

Research kitchen

I went back and researched female fishers with young, read about the delayed implantation that the fertilized egg goes through—like river otters and mink alike. The fertilized eggs float unattached for roughly 10 months, before attaching for a month long gestation and then birth. Fishers give birth to youngsters in a natal den, but will move them to a maternal den after not too long. The kits are born with eyes closed, which then open after seven weeks, and are weaned after ten weeks. At three months kits are crawling and climbing in their den, and by four months the kits are running, climbing and exploring outside. The young will stay with the mother through the summer.

So was that BTA cavity the natal den? Would the female bring her young to the cavity she uses out back of our house? How would I know, how could I know without having way more impact that I would ever want to have. So I walked…

So what next?

I visited stands of trees where I had tracked the fisher before, and started looking for big BTAs, especially ones with cavities. I found the search to be quite pleasurable, and have realized I will never look at Big-tooth Aspen the same way again. I gained appreciation for the Xanthoria lichens that seem to favor the BTA branches and trunk as they reach higher into the canopy. Looking to lichen for help identify deciduous trees in winter is new for me, and I tip my hat to the bright orange addition to the landscape. Colorful lessons. I like orange.

Xanthoria lichen

Xanthoria lichen

Anyway, there were plenty cavities to be found, and now I have a nice collection of tree cavity photos. None of these cavities found had scat below, however, which is fine… fisher are stingy with the scat.

Since we are not expecting any fisher kit sightings for a few more months at least, I moved my trail camera closer to the den out back, and sure enough she triggers the motion sensor most nights, all the way through April. Are the young ones getting ready to open up their eyes up in my BTA tree? Is there anybody out there? Only time will tell.

In conclusion

So the lessons were there all along, as they always are. Sure, estrus in snow helped get things moving, and the fisher getting treed by a neighborhood dog was a big help. But the cavities and scat are there whether estrus is found, or fishers are treed. Learning from these lessons, makes learning future lessons easier. This is a major part of what makes lessons so wonderful, each lesson gives you more experienced each year, each March.

We’re not done with this rearing cycle (like I’m part of this effort in the least). We’ve only just begun really. These are the lessons I learned while complaining (sometimes loudly) about the lack of snow (I think I am starting to get over that and have mustelids to thank). Snow is good for tracking, but it can also be a crutch. In the end, it’s not the snow, it’s the fisher.

With these lessons in the proverbial “back pocket” we can now move forward with the fisher learning regardless of snow conditions. And while that may seem like an obvious epiphany it is also a breakthrough as most obvious epiphanies are. So, thanks fishers, you are appreciated both intrinsically and selfishly!

Hope to see you out there!

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