Hey everyone, my first post here. I'm still a pretty new trapper but I have been browsing the forum for awhile.
I remember once reading that with marten a mostly male catch was what most aim for, maybe 80% male if I remember right. I started water trapping last year and have a small stretch of river that I've caught 9 mink since and all but one have been male. Would this point more towards a healthy mink population or is it impossible to tell?
I don't believe I'm trapping the area out but I think my favorite part of trapping is I know that I will never run out of things to learn!

You have a nice population of mink there.I'm willing to bet some of the male mink were young males.

I'm glad to hear that. I was thinking the same but what do I know? Not a lot!
Four of the males were big, they had to go on my XL mink board and from my limited experience and knowledge, I would bet the rest were younger ones. They fit perfect on the male mink boards.

Male mink travel a lot farther than the females so more chances for them to find your traps. Females have a smaller home range.

I’m guessing 60-40 ratio is about normal. I love seeing a high ratio of young mink on my first check and the weather fronts sure help for those huge males that are nearly absent during stable high pressure weather.

I’m convinced our population around here is WAY down from where it was several years ago. I run more and more blind sets every year along our coyote line. And the mink catches are becoming few
And far between.
Started out in 90s as a fun side line and could count on picking up enough mink to make it interesting. Now I’m (This word is unacceptable on Trapperman) lucky to get one a season in same locations. I see a few in summers along the rock dam faces at public lakes but even those are fewer than we used to see.
I’d be curious if it’s habitat, or drought, or maybe even farm chemicals causing their lower numbers.
I sold one large male last year in February and my buyer told me that was the very first mink he’d bought all season. In February! That season opens in November. Wow.
So yes I get way fewer juveniles and most of mine have only been large males, can’t even recall the last female I caught.
Jim

This is your answer.
As far as marten the target is juveniles of both sexes and adult males.
Like mink,female resident marten have smaller home ranges than males so you can exclude some adult females by spacing sets farther apart.

Mink are much more prolific than marten so overtrapping is not nearly as much of a concern for mink as it is for marten.

We have a lot of mink down here and most of the ones I catch are bucks. It is pretty rare for me to catch a doe. OUt of 50 or so mink i average a season at least 95% of what I catch is big buck mink. It all due to how much a male will travel, from what I read up to 30 mile range.I also target areas where I have traditionally over time have caught bucks. When I say we are coverd in them, we are over-ran with them.

I kept records for several years on this and it was always roughly a 60% male to 40% female ratio. The mink population in the area I've trapped for years has also declined recently.Dont know what the cause is. I've trapped some of these areas for 60 years and haven't noticed a big change in population until 3 years ago.

I wonder what is making them decline? Our mink population is out of control, due mostly to lack of trapping and crawfish farms. Crawfish ponds are over ran with them. I know that mink will move on if the muskrat population declines.

One of the main thrusts to the mink study for the Dioxin Prj was to determine the density/population of mink on the miles of 3 different river systems within the overall Project area. The Habitat Indexing Study(s) for mink was part of our SOP of which I participated! It actually proved itself on the Project and verified and explained why some stretches of river was barren of mink and other stretches had some sort of a viable population.
https://www.pacificorp.com/content/...ementation/hep-models/USFWS_HSI_Mink.pdf

NY did a similar study in the upper Hudson years ago because of the PCB contamination. I know a member on here trapped mink for the study but don't remember the details except no mink.

Very interesting! No mink eh???
About a year after I’d finished the Dioxin Prj (2004 or so) my professor contacted me with an offer to work another contamination project in Upper NY State. He wanted me to travel up there, hire trappers, scout a river, and teach the bottom edge set. He told me I didn’t even have to trap! LOL I turned him down! I’d traveled for DOW and as an after retirement consultant across the country to fab shops helping fix weld related QA/QC problems and told him I don’t travel anymore PERIOD! He was PO”ed and I’d bet it was the same project you described!

Thanks for all of the responses guys. Before I started targeting them I didn't expect there to be much of a population being in the high desert but I have been pleasantly surprised!

That just doesnt happen here in PA. We havent had much of a Muskrat population for 25 years and the Mink population is as good as ever lately for some reason. They sure dont need muskrats arond here but Im sure they miss them as I do.

As far as traveling, maybe during the rearing of the young but why would it be any different any other time?

Lack of water for longer periods than 3 months (drought)
Lack of prey due to lack of prey habitat (measurable)
Lack of overhead protective cover (measurable)
Increase in owls & hawks
A virus

You might find some clues & reasons in the Habitat Suitability Indexing study.

One thing I learned by working the HSI study is that the length of travel of male mink isn’t miles & miles but it is several times longer than the females. If male mink’s travel were very many miles, they would backfill where mink had been trapped/killed quite quickly but I proved on my waterways during & after the Prj that certainly wasn’t/isn’t the case!

I had quite the argument with a trapper from WI about this very thing and he professed that his mink sets just kept right on producing steadily. I tested is theory for 2 years by leaving my BEs in for a little over 2 months AFTER I’d caught mink between night 3 & night 9 on average. 2 years in a row I never caught another mink during the two 7-week periods!

During the mink study and when the DNR & EPA required I repeat my catch performance on a specified stretch of the “river of concern”. I couldn’t find mink sign at any of the previous catch locations (3 weeks later) which were my primary set locations where I figured to quickly make catches. I had to set the secondary locations that I’d located during the initial scouting still showing sign. I hadn’t set them since the primary locations I determined to be better odds of making for quicker catches. I never caught another mink at the set locations where I’d caught the original quota BUT I caught the new imposed quota at the secondaries!!!!!

A person reading my posts might ask “why so involved?” When I interviewed for the Project I was told I would be expected to act & perform as an expert witness in Court. Since one of my key job responsibilities had been an “expert witness” during my career at DOW pertaining to welding & fabrication I knew what I had to do to satisfy the QA/QC requirements of the Project.

Great discussion.

Lack of water for longer periods than 3 months (drought) Lack of water and lack of prey go together- no fish to be had they probably ramp up on the mammal diets. Ive seen some lean water all summer yet the mink population was there that fall.
Lack of prey due to lack of prey habitat (measurable) See above.
Lack of overhead protective cover (measurable) I dont think that matters much at all, look at all the mink longliners in the farmland midwest with nary a tree or bush in sight.
Increase in owls & hawks Well, yea, sure- they are hard on everything.
A virus I cant comment on this, I have no experience in that field.