Possibly the most important piece of information ever posted on trapping! Protect the resource and manage for maximum sustained yield! Thanks for sharing!!!

Sobie2

Jack,
Thank you for that important fact. I have heard, read, and made note of this very thing.

I greatly appreciate the reminder, kinda drive the point home. I'll be very attentive to low sets as ler percentages.
Let's keep those ladies producing, 2.5 littered is rough enough.

Thanks again Jack.

Agreed.!

Jack,
I saw you mentioned the elevated sets to avoid females. For sake of discussion, I'm curious how you determine a female will walk by an elevated set, that a male will then get caught in. Or for example, how do you determine the female you just caught in a ground set, wouldn't have also climbed a pole? Just saying you'll catch more females on the ground is something that has been passed around on here for years, but in my experience isn't really a fact anyone can prove. My experience has shown, when marten are being picky, many marten (both male and female) will walk by elevated sets, and get caught in ground sets. They will wander around under boxes, inverted coni flower pot sets, or poles, then wander on down the line, and often get caught in a ground set (again both sexes). Or sometimes follow along the trail, beach fringe, or snowmachine track for a few miles, passing up set after set, then finally climb up, and get caught in an elevated set. No real reason I guess, other than maybe they finally got hungry, or curious enough to bother. When these picky times occur, being a fisherman also (I call it going off the bite), they usually seem to be pretty widespread. Makes me think it's atmospheric/ weather related, or a seasonal time like I mention later, I tend to see this mid JAN.-mid FEB.

My experience has shown more importantly that DURATION of traps in an area is something to watch out for. What will tend to happen up here, is guys set an area opening day, and don't pull until it closes. You'll commonly catch some males at the start (bigger home ranges, so more likely to have multiple encounters) males overlap/ share home ranges A LOT. I actually don't think males have nearly as designated home ranges as females, females tend to be more tied down, pregnancy/ kits, at least some of the year. Males will just wander, we recorded movements over 60 miles in a couple months time, so probably just wandering willy-nilly. Anyways, the longer those traps sit in the same area, the more likely they will be found by a female, who tends to not cover as much ground. I like to move in, set traps for 2- 4 short checks, then pull, and move on. Leaves seed for next year, and yields high male catch rates. Actually higher catch rates overall, being on fresh ground all the time, unfortunately also take tons of work

So many factors at play, ever notice how your ratio of females skyrockets a few days before/ during/ after a full moon? I swear some areas just have more females!! Someone I know has a valley he traps, that always seems to have a higher proportion of females, compared to everywhere else, been that way for 35 years, consistently?? Strange!!?? Types of lures can even possibly play into male/ female reaction. Time of year also. My catch rates on females have always gone up about Jan 15th-Feb.15th. To be honest with you, I don't worry whatsoever about male to female ratios, unless the female ratio is including adult females. Juvenile females in abundance is a GOOD sign, of high reproduction. Although I guess if I ever saw a big check or two of mostly all juvenile females, I would wonder why????........while pulling traps!!!

Good rule of thumb for the original poster, 4 or more juveniles, per adult female ratio, is what you want to be seeing.

To many more thoughts to type, I'm a hunt and peck typer Any thoughts on these comments??

trapped4ever (and whoever else might be interested).

Great questions, all. First off, how does one infer that females will avoid elevated sets? In doing a couple decades of necropsies on marten carcasses that were turned in to me, in the western interior of Alaska, in central Alaska and in SE Alaska (ABC Islands), then in Idaho, when I was often looking at well over a thousand carcasses per year, it became obvious when looking at these collections which trappers were using ground cubbies and which ones were using elevated sets. Simply asking them pretty much confirmed my suspicions. The trappers using largely elevated sets would tender collections that would average 10-15% higher ratios of males in their harvest than those trappers who were using ground cubbies.

I certainly agree that trapping the same area for long periods of time also generally increases the proportion of females in the annual harvest. In these large sample sizes I was getting, the November ratios were usually heavily weighted toward males; often 70-75%. In December, ratios would decline slightly to around 60% males. January was usually around 55% males, and the February catch would usually plunge to 35-40% males. As you mentioned, however, there were a few trappers that continually moved their efforts to new grounds throughout the season, and their harvested sex ratios generally stayed well over 60% males throughout the season.

From my own marten trapping experience and from the carcass work that I did, it became clear through the years that indeed it was the relatively high incidence of adult females in the harvest that hurt subsequent year's harvests. However, it is difficult at times to determine if a female is a yoy, a yearling, or is an adult. The coalescence of the muscles at the sagittal crest works well for males, but is iffy for females (there are better ways to do this). Anyway, that is why I originally came up with the 4:1 ratio of yoy:adult female in the harvest as being critical. It was actually Midge Strickland in Ontario that suggested a 3:1 ratio, but for Alaska and Idaho marten populations, the 4:1 was a bit more appropriate, and seemed to work very well. Obviously, ratios of 5:1 or 10:1 are better.

I am not a fan of government regulation. Our trapping regulations are often already too complicated. I was encouraged many years ago to submit regulation proposals to the Alaska Board of Game to make it legal to only trap marten with traps elevated at least 36" off the ground. I resisted. In Interior Alaska at least, if a trapper wanted to 'mine' his marten populations, let him (or her). If another trapper was in it for the long run and preferred to maximize their long-term harvest, so much the better, and the suggested 4:1 ratio was offered to these trappers as a way to maximize their harvests on a sustained basis. Too, those tappers that were targeting mink (or whatever) and were incidentally taking a handful of marten would legally have to turn those marten in (basically wasted resource) if the traps were not elevated.

Are there situations where ground sets are reasonable for sustained annual harvests of marten? Absolutely (but perhaps a topic for another discussion).

Happy trapping!

Jack

Jack,

Some more questions on your deduction. Don't take this wrong, not trying to be argumentative, just curious on your thoughts. I have no doubt you are far more knowledgeable than me on marten, that's why I'm asking you! How many variables did you record for this "experiment". I assume date and location of capture? What about type bait? Lure? SOME believe marten gland lures increase their male catch ratio, either way, different lures can elicit different responses to the different sexes. Type of trap, and condition of trap, (waxed, good shape, or old rust bucket bodygrip, that triggers are sticky on), even something as simple as bodygrip trigger types and condition, pans or trigger wires, can often affect male/ female catch ratio's, how was the line being trapped, sets left in place all season? or rotated to new area? Duration of checks? Weather? So many variables, so few controls....... How would you even know the overall make up of males to females on any said given trapline, before harvest started? I guess you can kind of infer if you saw the same thing repeatedly, it ups your probability at least.

Having personally trapped thousands and thousands of marten, here is what I have observed. Marten are more likely to get caught in a ground set, than an elevated one at the same location, both males and females. Later in the year, or in an area of higher abundance females (good reproductive years), my female catch ratios go up. However, what I've always seen, is my female catch ratio goes up at the same rate, in both ground and elevated sets. I don't know if it's that they are hungrier, more curious, territorial, fattening up for impending implantation, or what?? It just seems female activity comes in waves, like I previously mentioned, around a full moon often. I would deduce IF females are indeed less likely to climb, these ratios should differ substantially?? Again just using information I have at hand, with no real controls for the "experiment", and like I said, I like to rely on my own observations, not just what I hear or read. I must have a "curious" nature, as I seem to always question what I hear/read, instead of just assuming it is correct:)

I've often also wondered if the females just get more active on a line, later in the year, due to many males being harvested, opening up opportunities for range/food. I don't think this is always the case though, because sometimes, if I set up an area that hasn't been trapped yet, my female percentage almost mirrors other lines that have already been checked a few times?? It seems there is more going on here, than just males being removed from the picture. My assumption is the males tend to be very territorial in high density locations, this is when you'll see them chew on others already in the traps. They tend to bite the vitals and or neck MULTIPLE times, I assume making SURE it's dead. In some instances, once the males are removed, perhaps the females become more active? The big picture to me, seems to indicate in general though, females tend to get more active later in the season.

I've trapped the same line for many, many years now, and understand and support the idea of sustained yield. However, marten run in 7-9 year cycles, and aside from that, there will be other influencing factors, mainly weather, mechanicals, etc, that will affect your seasonal harvest. How much refugia is available?? On building populations, I can't personally trap enough marten to stop the increase in my area, during the year of the crash, you could not trap at all, but the population will STILL be way lower the next year. Just a few more random thoughts....

Sorry, 358wsm, kind of derailing your topic. Maybe I should just PM Jack.....You'd never guess my trapping season just ended:(

Also, Jack, THANK YOU for not supporting the elevated trap proposal. On the RARE occasions mink prices go up, I like to run some combo sets, on the ground, and these will catch plenty of both species. Thanks for all your years of work up here, and Alaska is NO DOUBT a better place because of it.

I was wondering when a discussion on farming, sustained yield, etc. would pop up in this thread.
Plenty of guys on here who think you can farm marten. That you can get a sustained yield. I disagree with those ideas. No, I'm not going to advocate trapping as hard as you can all season long. Since a trapper can only cover so much country, he can only effect that much country. If your a hard working trapper, catch will likely fall as season progresses and you will likely stop.
The trapper is only there for about 4 months. He only effects the number of marten left to reproduce in his relatively small area and the number of adult females left to give birth. Remember, the marten left in March won't breed until Aug. They have to survive the spring and summer. The females have to raise the young they were carrying successfully. Trappers don't effect the weather. They don't effect kit survival. They don't effect the microtine population and they don't effect FIRES.
I like this quote from T4E," On building populations, I can't personally trap enough marten to stop the increase in my area, during the year of the crash, you could not trap at all, but the population will STILL be way lower the next year. Just a few more random thoughts...."!!
mt

T4E,

It's no problem, I enjoy learning stuff.

I'd actually prefer that you DID NOT resort to PM's and allow everyone the education.

Thanks.

martentrapper, (and 358wsm, trapped4ever, etc...)

I think you make a good point. Obviously, the way I put my opinions above, I inferred that, managed correctly, we could get sustained annual harvests from a marten population. However, like any farmer, yields are going to be variable no matter what we do or how well we take care of the resource. On the exact same acre of ground, will I get the exact same yield of wheat year after year if I'm doing things 'right'? 'Course not. By the same token, I don't think you can 'bank' marten. I've heard countless times from people things like "That piece of ground hasn't been trapped for five years. It's going to be packed with old, apple-headed males." Doesn't happen.

On the other hand, I have seen areas with a couple different trappers working adjoining valleys. One guy works it very reasonably, quitting when his yoy:adult female ratio nears 4:1. The other guy keeps at it, hammering it into February, and his harvest ratio at the end of the season is 2:1. The next year, the harvest (numbers) is very different on the lines, with the first guy still enjoying reasonable numbers and the second guy barely able to find a handful.

And yes, just like the wheat farmer, other factors (weather in particular) are going to influence marten populations. We will never see constant, stable populations no matter how good stewards or managers we are, but we can, and certainly do, have an influence on those populations on a critter as easy to trap as a marten. I'm a firm believer in the 'predator pit' theory, and, similar to wolf:moose predator pits, I believe there can also be a trapper:marten predator pit, and we should try to avoid that scenario.

100% agree with Gulo^^^^^^

Go to AK.

IMO, the more you stay out of the heavier white spruce, riparian habitat, the fewer females you will catch. Stick to that nasty black spruce and swamp "edge" areas and your male/female ratio will be better than if you are trapping along the river corridor. That might not be possible in some of the areas of SE AK.

But I am convinced that males will more readily inhabit the riskier, more challenging environment than females.

Thanks for chiming in on this White.

Do you suppose the bigger males being willing to 'risk' the more open habitats has anything to do with owl or goshawk predation on the smaller females?

Boco, are you seeing the same as White17?

358wsm, are we getting a bit far afield from your original question?


Jack

Man, I love it when Gulo and T4E get going! There is information that can't be bought.
Thanks, guys! Keep it coming

Seeing is believing. Only 99% here. Anytime I break into a new un-trapped for awhile area it tends have more male apple heads, but not necessarily a dense population of marten. My trapped areas tend to have a higher female composition to the marten population than untrapped or lightly trapped areas. More females should result in more reproductive capability.

I have had two years this decade where it appeared that there was almost a complete failure to recruit new marten into the population. No harvestable surplus. I pulled as soon as I recognized this. Should I have just trapped the adults?

What I have seen and what has worked for me,if I am trapping later in the year because of very high juvenile numbers overall,I will stay out of the old growth balsam/mixed forest types.These areas have a lot of downed coarse wood on the ground and lots of standing dead chicot.In the past when I trapped these areas late this is where I caught the most adult females.I believe they use these areas in late winter because it is good denning area and it is easy for the female marten to hunt under the snow.The male marten do wander a lot more at this time of year and they are often running down rabbits,so my harvest late is mostly adult male marten which keeps the ratio at a safe level when trapping later.
I am not a fan of the refugia method of managing marten.Marten are known to abandon home ranges over wide areas every few years when there is a scarecity(crash) of prey animals.The refugia method does not work in those cases.
I believe marten are somewhat like beaver when it comes to home range.Marten mark their area with scent.Beaver also mark their area with scent.Trap out the beaver and the adjoining beaver will know from the castor mound that there are no more beaver there and will come in.
I believe marten are similar,why a marten box at a good location can catch several adult males over the course of a season.
Marten will also take advantage of big baits and tend to stay close by.I believe this encourages other marten to come into the area.I have found marten caught in a set at a bait dump are often scavenged and partially eaten by other marten vying for the area.
Adult female marten will stay near a big bait late in the season and they fatten up immensely and very quickly.
I generally avoid setting for marten at large baits late.When I set boxes with a large bait nearby early I always set multiple boxes to avoid the cannibalism on extended checks.
I believe marten are a lot more territorial than most think.And it is the main reason juvenile marten disperse so much over long distances in late fall.Natures way.Gulo can correct me if I'm wrong but I believe the marten genome,like lynx is almost identical over a wide swath of northern north America because of their ability to dispese over long distances.

Well, my derailment has been derailed!! I thought we were discussing whether females are really less likely to climb to an elevated set?;)

I had about 4 paragraphs of "well thought out discussion" typed, and the internet ate it:(

Instead I'll just throw out more discombobulated garble. I see more material I disagree with, and some I can agree with, has appeared.

Regarding refugia management, there is WAY more to it than just leaving some un trapped area around your line. Is it high carrying capacity refugia, or worthless unproductive ground? How much refugia do you have? Are there other trappers in close proximity? What is the habitat/ geography like? One thing that doesn't get discussed a lot is ACCESS. Now some areas you can access the majority of the good marten habitat from a snowmachine, and some areas you can access NONE of the good marten habitat from a snow machine. Some flat lands are good for marten, some aren't, same with mountains. Areas in the interior that have lots of good access, are prime examples, as they are often in the trapper/ marten pit that Jack mentioned. Just to much prolonged pressure, and nowhere near enough quality, inaccessible refugia.

I've seen Boco mention not being a fan of refugia methods of management before. Are you simply speaking of the years after the decline, or ever? My experience has been: marten run 7-9 year cycles, following the microtine food base. On the building years, I can't trap enough marten to make there be less recruitment the following season. The Fall dispersal of YOY and wandering adult males fills these trapped areas back in every year, until the die off. What you will see the last big season, will be mostly adult marten with almost no recruitment, female uteruses will indicate very little reproduction. I generally always trap hard during the building years, and during the final year, where the catch is mostly adults. Then, I minimize efforts for at least the next 2 years, to maximize recruitment. Like I said in an earlier post, when the population is climbing, it's hard to affect them, UNLESS you don't have enough quality, inaccessible refugia, OR to many other trappers surrounding your area. Obviously there can be weather/ prey base anomalies. When they are crashing, my thought has been you might as well harvest, because they will crash whether you trap or not. Do you disagree with this Boco? You say these marten abandon their home range, are you thinking this is because of the microtine crash and lack of food?? If so, what other management strategy is going to work better, if there is no food? No food means they'll move or die, PERIOD!!
Are these marten getting together and colluding to avoid the trappers lines when they do move out of said home range refugia they are abandoning;)? Of course if a line is good productive neighboring habitat, some will disperse into it. This is basically part of what fall dispersal of YOY marten IS, finding a productive hunting area, that isn't already over run with marten. I do agree when they crash, there is no type of management that will keep them in high numbers, but I've never been clear on what strategy you find superior for managing microtine crashes causing marten to abandon the area?

It seems we all agree minimizing adult female harvest is ideal. So there is a start!!!

Dirt, was your experience with the un trapped area producing males early season or late? I've often had the opposite happen, if I set up a line late season. For example, 2 years ago I set a valley at the start of February that I hadn't set in 15 years, as on my other lines the female % catch rates were starting to go up, and I was hoping for a good pull or two of males. Didn't happen, as my female % catch rates were the same as the other lines, and these were all elevated sets;) Not the first time I've seen this. Early season lines on long term un trapped ground have yielded similar results as yours though. Still makes me think females around here are more prone to be active/ traveling further, late season. Putting on fat for impending pregnancy, searching for den site for birthing?? Don't know.....

Boco, really really interesting to me that your male harvest goes way up in the late season. Almost every trapper I know up here, that put's up any numbers and has many years of experience, sees female catch rates go up late season. Kind of interesting to get perspectives from so many different regions.... Is this a normal occurrence on your line, or just this year, due to good recruitment? It sounds like you have the same opinion as me, on how territorial marten can be. This late season I followed a big males tracks for a couple miles down the line, as he passed about 5 sets, with no interest. Then he came to a set with a frozen female in the trap, he went over and bit her neck/ vitals, like they tend to do in these situations, then went to the next set and got caught. Obviously that female induced a territorial response, but did she also encourage a competitive instinct that made him finally think he should get that next bait, before one of these other marten get it??? Who knows??

There is no late season trapping here. I'm usually done by mid Jan. I'm on year one of light trapping after the crash year; trying to recruit like you mentioned. My big number years include plenty of YOY. These usually occur on big vole abundance years. It is in the crash year that all I mostly have is adults. No voles; poor recruitment. I count on refugia, but I have mentioned before I cannot be sure from year to year if refugia are not being trapped, therefore I leave marten in my trapped area as a safeguard. Hopefully they are females.

If I don't watch where I trap,the catch of females definitely goes up later in the season.Of course core habitat for marten outside of the James Bay lowlands is old growth large mature boreal forest.Not true in the lowlands where old growth forests are 3feet high.In 2005 we had a widespread food crash for marten in Northeastern Ontario.Marten abandoned their home ranges in large numbers.It is easy to tell when that occurs where I am as the big marten from around the bay will be caught down here every time this happens.Trappers were giddy harvesting large numbers of nice big marten right into late winter.I stopped trapping,after Christmas that year as the juvenile ratio was not there.The next year there were no marten at all.Trappers did not trap after a few runs on the lines with no marten why would they?Most times following a crash the next year there will be a noticeable rebound with juveniles in the harvest.Not this time.Two years no marten.Big panic in the ministry etc.never seen a crash like that before.Huge areas of good core marten habitat refugia like the white river game preserve had no marten over the same period.They all left and were trapped out by the surrounding harvesters,who thought the refugia method would work like it normally does.It did not.3rd year I caught 54 marten with a good young of year in the harvest.Speaking with other trappers who quit trapping early because of the lack of juveniles,in the year of the big food crash,they had harvestable numbers two years after.


So my lesson from this is that if there is an absence of juveniles in a managed marten population,when there is a high number of adults constantly on the move,It is wise to curtail the harvest early in order to give the surviving marten a chance to re populate good core habitat.Others are of the opinion of trap them all,they will starve anyway.(I do not agree with this).
I use the ratio method of management and apply the half mile spread between boxes to avoid some adult female home range in core habitat,I have also identified timbered drainages that run thru old burns, timber harvest areas,and muskeg,that connect core habitat.These are the areas that produce high numbers of dispersing juvenile marten in the fall with some single sets producing a good number of juveniles. I also use the native cree method of pulling sets before the new year.
There is nothing wrong with leaving large areas of core habitat untrapped,but In my opinion no matter how you operate the goal is to keep the harvest of adult females to a minimum percentage of the overall harvest as much as possible.
I also see that large untrapped areas are not as productive as judiciously trapped areas.
I have never tried the hit and run method like you mentioned T4E,but I have no doubt it works well in your area.
Each area is different,I could not imagine having the numbers of marten to trap that T4E has and I am sure he is a great steward of his resource and does what works for him.
I have just related here what has allowed me to harvest consistent decent numbers of marten over several decades on lines in NE Ont.
Oh,and all our marten here climb eventually,although not every time,nor every set.They can be a bit fickle at times.

This is getting into biological carrying capacity territory. My input here would be this....
If the food base crashes, and you don't trap at all, the marten will still crash, as they have exceeded maximum biological carrying capacity. If you harvest more than sustainable yield at ANY time, you are by definition going backwards. Recognizing populations are in constant flux is important to management.
Boco, I suspect you face MUCH more competitive trapping densities than me. Meaning more trappers operating closer to your lines than me?? Don't know.... in your scenario that happened on your line, what do you believe made marten reappear on your line, where there had been none for two years?? Or did you mean you left ample seed stock by pulling early, and left them alone for two seasons?? I don't really understand how your line would go from none, to surpassing all surrounding refugia suddenly, as in theory, the surrounding untapped, refugia should have similar numbers?? Why would just your line suddenly uptick?? The adult males and females in the refugia have been left in peace remember??

I guess it should be clarified that refugia management is not always an option, due to things like easy access of all quality habitat, other trappers in competition, habitat destruction like clear cutting, etc. However, don't mistake over harvesting a lines sustainable production, as a failure of refugia methods. Two different subjects. EVERY trap line has a maximum sustainable yield, that is constantly in flux, exceeding this means numbers fall. The trick is learning to read the natural ebbs and flows of populations, and figuring out our part in the dynamic. Obviously, it sounds like in your scenario, some of your neighboring trappers exceeded their harvestable yield, thinking the marten were goners anyway. I think one time, in the last 35 years in my current area, I may have harvested to heavily on the peak/ starve or move year. Not sure though, because even areas that hadn't been trapped for 10 years, were slow for the next couple years. There is so much untrapped ground up here, if you get away from urban areas, that it's easy to try a new, untrapped area as a control, to compare to what you are seeing on other regions of your line.

It would seem to me in your scenario, you just turned your line into untrapped refugia, hence the more rapid recovery??? No????

Does this mean untrapped, inaccessible refugia is the only tool in the tool box, for managing a line. Nope, not in my opinion. Does it work in all cases, probably not, but I think it will GREATLY help your odds of being able to have strong, sustainable recruitment. I would venture to say having a line surrounded by a proper buffer of refugia is FAR more important to sustainable yield in my area, where so much top class refugia never sees a trap, than me watching my ratios. Simply because, as I keep saying, when they crash, they crash, period. No amount of refugia, or high male % ratio will make up for a total lack of successful breeding, due to starvation. Can I affect recovery, if I trap ruthlessly, after the bottom of the cycle. I would certainly think so, but once again, that would be due to me exceeding my harvestable surplus. It isn't like you can reach a certain number and sustain it indefinately, unless you are talking lower volumes of marten trapped, or if you are covering huge areas, in which case, the lack of catch rates should be pretty noticeable.

So...... my opinion here...... guys like the original poster 358wsm, consider adjacent lands to wherever you choose to develop your line!