A few of you know that I have looked at literally thousands of marten carcasses from various places in Alaska (Glennallen, 1981-1986, McGrath, 1987-1998, ABC Islands, 1998-2003, and Fairbanks, 2003-2008, regions) and Idaho (various locations, 2009-2020) over the past 40 years. Mainly, I was trying to figure out reproduction (and what affected the number of blastocysts in adult females), and diet (and parasites, among other interesting tidbits).

Pretty consistently, North American marten subsist on voles during the winter. Red squirrels, grouse, and snowshoe hares make up only a minor portion of the diet. Mice and shrews likewise. I know that berries and birds are utilized in summer, but I don't know the actual percentages, as getting a decent sample size in summer is problematic. In SE Alaska, at least on Baranof and Chichagof Islands, it was pretty obvious that severe winters, when deer were pushed down on the beaches and many succumbed to starvation, I generally saw good marten reproduction and neonate survival during the next year. I could only conclude that the bonanza of food (beach-killed deer) was very important to those pregnant female marten in bringing off their litters. I suspect that winterkill (caribou, moose) may also be very important in survival of young marten in the interior. But, first and foremost, it is the voles that "run the system".

What affects the vole numbers? To me, based on thousands of snap-trap nights during the summers and through literature searches, voles in North America are not cyclic (as they appear to be in Eurasia). Many of you might argue this statement, but "cyclic", by definition, infers that the ups and downs of populations are predictable. In North American voles, the ups and downs are not predictable. There might be forty-fold differences in population density of vole numbers, but they are not "cyclic". Based on these thousands of museum special snap-trap nights and computing catch-per-unit-effort (X number of catches per 100 trapnights) it finally became evident that vole numbers were controlled by winter weather. A good snow pack is an amazing insulator. Most voles are sub-nivean throughout the winter, and, even in OAT (temps) of -40 degrees, the snow/ground interface is pretty constant at around 0 to 10 above (F). However, if there are mid-winter or early spring (January-March) chinooks (warm spells), the insulative value of the snowpack diminishes greatly, and thus, the voles get wet. A wet vole is a dead vole when the temps again plummet following the chinook. Especially in the spring, when marten are whelping and the adult females are lactating, food in the form of voles is understandably important. Without that food, no successful reproduction and/or no survival of the neonates.

As white 17 already pointed out, a 50/50 ratio of yoy to adult marten in the harvest is very poor, and it is likely that next year the marten numbers will be grim. Although it's a bit tricky to get accurate age class on some marten (especially yearling versus adult females), it is important in managing your lines that your ratio of yoy:adult females in the harvest not drop below 4:1. 6:1 or 8:1 or better is the desirable mix. Adult males seem almost immaterial. Apparently, there will always be enough of them around to take care of the breeding. What you want is to not take out too many adult (2+year-old) females. Elevating your sets seems to reduce the percentage of females in the harvest, while cubbies on the ground (or snow surface) are more likely to capture females.

I hope this monologue has been helpful, or at least given some of you some food for thought. I can only speculate (PIOMA) on the long-term absence of marten over certain areas.

Jack

Great information Gulo! Thanks so much for sharing!

Thanks for the infill Gulo.

Ricks area and mine is in a severe drought since July and the mushroom crop has been effected, limiting the Red back vole population of it's food source.
Jurassic have you set up any traps this fall ? Your only 30 miles north of Rick's trapping area .

I didn’t get any traps out this Fall cause I was too busy this year. Any spare time I had I spent it archery hunting and checking trail cams.
It’s a bummer cause I was really wanting to go hard at it for about 6 days.

Awesome info, we haven't had much for vole presence that last four years or so here. It was 2012 or 2013 that we had lots of voles, can see them coming out of the snow as we drove along out the country. Got marten in wide open areas where we don't usually get them. Hopefully we will get a good population of voles soon.

Here, we have had low snow cover, and wet to extremely wet springs, (and a summer to make Noah envious), for a couple years, now. And my small lines have seen a decided decline in marten.
On the other hand..........

Thanks Jack as north of 50 said we were very dry since July another factor could be COVID I know some of the mink caught it. Lots of unanswered questions but I do know there doesn’t seem to be as many as last winter

I know that mink have apparently contracted CV19 but I have no idea whether marten could also become infected.
I think it is important to not make that leap of logic without something to go on.

Gulo or Northof50 would have better ideas on that than I would.

Thanks for the info Gulo. I don't go in there often but one time I cut open a martens' packed stomach and it was full of rose hips.

I see them feeding on frozen high bush cranberries in winter here alot when the snow is deep.

Interesting thread.

let's take this quote from Gulo," I could only conclude that the bonanza of food (beach-killed deer) was very important to those pregnant female marten in bringing off their litters. I suspect that winterkill (caribou, moose) may also be very important in survival of young marten in the interior. But, first and foremost, it is the voles that "run the system".

The overall idea, as I see it is FOOD is the determinate factor in successful raising of kits. If females do well, the trapper has plenty of marten.............most of which would be YOY. If they don't do well, YOY are more rare or maybe even close to non existent. So how does a trapper have any ability to "manage" his line if food is the driving force. We can't control food. I figure that the trappers ability to really know if the marten food is in good supply is pretty low. Counting YOY/adult female only tells you what you have right then. It doesn't tell you what happens after you shut the line down (late Feb or march) and it doesn't tell you if the coming summers kits all survive in to the next trapping season.
After 40 years of trapping marten, or talking with others who are trapping, talking to furbuyers, talking to biologists, marten populations in Alaska can change up or down in short periods of time. Those changes are rarely brought about by how many marten a trapper catches.

martentrapper, (and others) -

Precisely! I agree with you 100%.

I would argue, however, that if food is indeed the limiting factor in marten populations, that trapping can affect the recovery time of that population. I have argued for in-season monitoring (by the individual trappers, not by ADF&G). Let me throw out a scenario for you to consider. Bear with me...

In November (interior) or December (SE Alaska), you are trapping your lines hard, and you catch 50 marten. This is your bread and butter, so you are monitoring the age- and sex-ratios. Of those first 50 marten, 6 of them are adult females,14 are big apple-headed males, and 30 are yoy. The young:adult female ratio is 5:1. Obviously, things are good, so you continue to trap. Unless you are continually moving into "new" country, your ratios change through the season. Males have bigger home ranges and are somewhat more mobile, so their chances of encountering a trap are greater. As you take off the "cream" (the males), your proportional take of females increases. Thus, it is "normal" to catch an increasing proportion of females as the season progresses. Your total harvest for the season ends up at 100 marten, 16 of those being adult females, 20 adult males, and 64 yoy. You're still good, as overall you're still at 4:1. This is a pretty typical scenario; I've seen it many times.

The next year finally rolls around. You've made it through another round of skeeters and the "good season" is here. You run your lines again in November, and you catch only 30 marten. Six of those are adult females, 12 are adult males, and only 12 are yoy. Not good. Your ratio is only 2:1. You see the writing on the wall, and you shift your effort over to trapping wolves and wolverines for the remainder of the season. Something changed dramatically on your line over the last year and you want to leave those adult females out there to hopefully re-populate the line for next year. Your neighbor, Goober, one drainage over, hasn't been watching the ratios. His take is down also, but he continues to trap, maybe even a bit harder, to make up for the shortfall. He ends up the season with 60 marten (to your 30), but he's really gotten into the adult females (the breeders) and his ratio is down to 1:1 (20 adult females, 20 adult males, 20 yoy).

You suffer through another summer, hoping the voles have recovered and that the marten did well. Indeed, your take is back up to 75 marten for the year, but Goober only gets 15. He had no breeder females remaining on his line. You, on the other hand, "farmed" your line, and the marten recovery was much quicker.

This isn't a made-up, feel-good story. I saw these exact scenarios play out in the interior. Granted, there's little to nothing we can do over a large area to ensure that vole populations are always high, thus ensuring good marten numbers. But I'm convinced that we can manage our lines, voluntarily reducing the take of adult females, and see the resultant recovery in a much shorter time period.

Jack

I keep a journal on catch records etc but its out at the line. I believe it was around 09 though, and it was widespread. Our population has stabilized, but is still not back to what it was. We a lot more winter rains now than we ever did before and I believe it has an effect. Two days ago it was -30, yesterday it was 0 and raining. One thing I've noticed for sure, is that these winter rains are hard on ungulates, especially caribou. The water seeps down through the snow to the ground and then freezes. This makes it hard for the caribou to get lichen. My theory is that it also makes it hard for marten to get voles?? In the last couple years I am convinced that the same winter rains have caused a moose die off on my trapline. Freezing rain coats the willows causing them to bend over, then it snows and a good portion of the feed is gone. Just my theory, take it for what its worth.

Goober traps north of me. Gooberland is to my east. Oh! It's real!

Big howdy wave from your Montana neighbor, Jack !

Aren't the high peaks just breathtaking with snow this time of year ? I love the early mornings and evenings when the sun turns them into glowing golds and rose apricot tones, with a dark sky behind them.

I really love these discussions about marten .

So great to have input from trappers and their experiences on the changing moods of environment and reactive fluctuations of their trapping territories. Good custodians insuring future populations , instead of the "bull in the china shop".(Lack of capitol C intended ) ... I always think of Trapped4ever , how he is so in tune with his environment and those amazing coloured ones he harvests every year...his hands on the heartbeat of the land he lives in , so very well.

I have saved your information from along ago about the marten types you have enjoyed from your studies in different parts of the world , like Russia . I will add these to my folder too.

Along with some of the other's observations and input from this sandbox.

And I don't even know the half....learning all the time. Adds such enriching depth in appreciation of the fur that I enjoy wearing .

Many thanks for your kind efforts in taking such time to explain the details that you have worked so hard to gather over decades. A treasure house shared.

Life is good.

Face to the wind....on the surface

I can see your point,Gulo. How about migration? If your drainage has more total females than goobers, can there be some migration as your females look for a home?
YOY females will not be bred when trapping season opens, correct? When those females become "adults" at one year of age, they are bred in Aug./sept. and don't contribute young until the following trapping season.

Dirt, you have been trapping the same country for about as long as this forum has been around I think. Since your not a "goober" do you have records of your management and it's success?
If a guy is surrounded by goobers, isn't his area effected by that?

If your vole population is too poor to lead to successful kit survival, does it also cause a loss of adults? Poor food resource must be harder on pregnant females or females raising kits than on males. The non goober trappers will suffer poor marten number if "food" doesn't improve.

Enjoy the discussions.

I think you are right Mike. If you are surrounded by Goobers you too will be affected...................depending on how close Goober is.
I have heard some discussion over the years that five miles apart is far enough. I disagree. I think there needs to be larger areas than that in between traplines.

I also suspect that females MIGHT breed at one year old but maybe not the majority of them. And those who can/will breed at that age still need to encounter an adult male.

Yes, I have records and a journal.

To know if I am successful, I have to have knowledge of what goes on in goober country. I do somewhat.

Home Ranges, Migrations of marten...

(I sincerely hope you all don't mind me rambling on about marten. Most of what I have to contribute is not perfect science. Most of it comes from a lifetime of observing rather than from scientific investigations with expensive telemetry gear and top-notch biometricians; I apologize in advance.)

If one looks critically at the telemetry data on marten, a 5-mile "gap" between traplines would appear to be plenty sufficient to insulate you from Goober. Even adult male marten don't have a home range that even comes close to 5 or 10 square miles. Too (and probably more important), the scientific studies using contemporary radiotelemetry rarely, if ever, mention migrations. However, many marten trappers have seen these unmistakable, one-way, mass migrations ("waves") at one time or another. They do happen, and are probably in response to either a lack of food (voles) or to snow/ice conditions that make that food source unavailable to marten. Adult marten, like most mammals, establish and maintain home ranges where they are intimately familiar with the landscape and know where the food resources are low and where they are high. It is in their best interest to stay within the confines of their home range...until the food base goes gunnybag. Let me digress a bit and introduce another conundrum (I promise, there's a point I'll get to). Litter size in marten is 3-4 young, once a year. How then, is it possible, even under the best of circumstances, to achieve a ratio of 4, 5, or even 8:1 in the harvest (total young:adult female)? Simple really. Those yoy marten are not usually confined to an established home range. They are somewhat nomadic, looking for an unoccupied tract where they can set up housekeeping. Thus, their chances of encountering a trap are much higher than the residents' chances. Consequently, it appears to me, 5 miles between traplines may not be adequate to insulate you from the poor management that is being done by Goober. Your area, reasonably managed, is providing dispersing marten into Goober's line, but his area is hammered, and it's contributing no dispersers back your way. Get enough Goobers around you, and it matters little how well you manage your line.

For five years (2003-2008), I had the dubious honor of trapping near one of Alaska's population centers (Fairbanks). This was after many years, in three very different areas, of trapping in less human-populated areas of the state. The area out of Fairbanks had people all around me. They were, unquestionably, Goobers. It was relatively good marten habitat, but my annual take was only about 8-15 marten. I'm convinced that overtrapping by all of us was responsible for the relatively low marten population. I adopted the same attitude as my neighbors; "I'll get those marten before they do". In hindsight, it would have been much smarter and better for all of us if we'd had a self-imposed moratorium for a year or two on marten; let the population recover, then enjoy the fruits of our "management".

Jack

Jack, I trust YOUR lifetime of experience over other's "re-SEARCH science " any day.

Never feel trepidation for sharing everything you want to . I imagine I echo other's sentiments here in how much your mind shared is appreciated.

I have to take a little drive but when I return I'm gonna enjoy what you've added .

Thank you !