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.

I’d say that you don’t have a mink population problem at all because you just explained why you have mink!

I do know because I participated in the habitat studies on my rivers that lack of adequate prey habitat along shorelines and overhead cover within 100m of the water’s edge is the main reason why I have an overall low mink population. That is scientific fact and since I participated in the studies I was there! That was the basis for all the excitement & criticism about my catch numbers that I eluded to previously. The mink population was low and the local trappers didn’t know how to use the BE in that kind of water fluctuation 25 years ago!

I’m in the midwest and I trapped mink mostly in farm ground. There’s not mush prey for mink when the fields are plowed to the edge of the ditch banks. We have sq mile sections here and if a mile of ditch didn’t have a woodlot somewhere in the section and abutted the ditch my records show that I would catch one mink during a 2-week set period. If the section contained one or more 40 acre woodlots I could figure to catch 2-3 mink.

If we had summer-long dry periods that lasted from May until the fall rains of October and most ditches were dried up, I wouldn’t catch anything that November unless a particular ditches did not completely dry up too long and catch rates would be about normal.

I average 3 to 4 bucks for evey female here in pa. Some creeks just seem to have more minks. They are some creeks that hold minks, and they will actually have dens. Then there others that seen to be more travle ways. Thoes creeks seem to be less productive but when u do make a catch it is almost always a buck...

I trap roughly 5 miles of a wadable river. I average about 1 mink per 20 rats over the last many seasons. I set up sections for 3 days mostly and move. That to me is one reason I feel lI catch about 50-50 YOY and females to adult males. I feel that I am catching several in and near their denning and home areas. I have one section that has always been a good place to catch a few mink but mostly the youn and females. I have caugh mink in my 160s on land in coon trails and they are almost 100% males.

Bryce

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

Just a fact of life, in most species (except those that stay in groups, herds, packs, etc.) males wander farther and have a larger territory than females. Mink, marten, bobcats, lions, deer, coons, fisher, skunks; the males of all these species and many more, on average have a much larger territory than females.

Not convinced that hawks and owls take many mink or muskrat as prey. Anyone know of a DNA analysis of owl pellets showing mink hairs? When you handle any owl or small hawk you will be surprised at how light weight they are so to pick a prey animal off the water (water soaked rat or mink) and not get flipped in the drink I would like to see. Jim stated the mink population where he traps by Lincoln is way down. I would say the same here in the Northeast part of NE. Probably a function of what everyone says but the drought conditions here would be a primary factor in my estimate. Also not a fan of male mink traveling miles along a stream with huge territories. I have BACKTRAILED an awful lot of mink in my life to see where they CAME from more so than where they are going. Trying to put it together showed they were "camped out" at a food source and were either running short of grits or were after "the girls at the dance" when they moved out of the area. Here it seems a mink will stay at a beaver colony, farm pond, brush pile etc. (even at a cattle feed yard) until the food becomes exhausted or too difficult to obtain so it must move. IF ITS FOOD SOURCE IS VARIED AND NOT CONCENTRATED as here, THEN,,,,,,,,,,, a hunt frequency of a larger area probably would be the norm. I remember a small hole in the ice at a large plunge pool CMP (corrugated metal pipe) on the outlet side of a good sized farm pond over 35 yrs. ago. That small hole was surrounded by creek chubs, green sunfish and a few bullheads that a big male mink had fished out of the water. That was 35 years ago and I monitored him (when I could) the rest of the winter . His (I'm assuming his) tracks never left the pond or outlet area until I lost them in the spring thaw. Estimated his home range at that grocery store was 4-5 acres. He would spend some time at an upstream concrete rubble pile hunting mice I assume (indicated by tracks) but he never left the pond area that winter. So my experiences with that one and many more through the years has formed my (however bias) opinions on mink populations here in farm country. In the wetlands and swamp country of MI, NY, LA, WI it may be totally different.................................. the mike..... side note: if you check the research, the # 1 predator of the muskrat in MI is the raccoon, (just like an opossum in a pheasant nest), coons eat the entire litter when they crawl out to a rat house or den in the springtime. ..... the mike again.

Great Horned Owls were extremely important to the Prj second only to the mink! The relationship and importance is explained in the Mink Habitat Indexing document I previously posted in this thread. That's one thing we were checking every 500m for miles of river bank!! Mink prey and mink as the prey habitat!! Can I tell you the % of mink fur & bones in the owl's pellets? Nope, but someone certainly does/did!!!


I believe there were 57 GHO nests natural & artificial nests on maybe 60 miles of the 3 rivers. The young people were trained to climb the nesting trees and take sample on the ground. As the old geezer on the Prj I was the Captain of the rescue boat. Remember all nests were on the floodplains so quite a few times the fledglings were old enough to bail out of the nest when a climber got up to it. The fledgling;ing would sail away since it couldn't fly and some landed in the river for me to retrieve. We never lost a baby owl! The photo shows me and the last one we had to rescue. For three springs the Prj rented a helicopter to fly the rivers and located nests with chicks so crews could float the rivers and do their sampling.





Here's a photo of the telemetry crew tracking owls. Notice the lower righthand corner of the railroad bridge abutment, I caught a large male mink in a BE off the corner in 4' of watter. Used one of my "plated" stabilaizers so I could just lower the trap down with a rod made for it.

Excellent discussion. I leave BE sets in the same place from December through the end of February. Regardless of their success rate. Much fewer 'rats compared to years before, but the mink population has appeared to be consistent with males outnumbering females at least 4:1.

This lower drainage of the Wisconsin River often sustains high water events for extended periods. Plays havoc with the muskrats and beaver, but IMO has little effect on the mink with hills nearby.

One food source that I see rarely mentioned is mice. If you're bowhunting on a dry, windless day, you'll swear there are herds of deer all around you as they rustle through the leaves. Often I've observed mink working dead trees over from bottom to top up through the cavities and on to the next tree.

Curious to know how many owls are in Michigan compared to Nebraska? Not near as much big timber in Nebraska, so stands to reason the owls may be fewer and farther in between and not as much of a factor, just a random thought not based on data.

I bought my land here in PA 30 years ago tomorrow. I had never seen a bald eagle and lived in this area my entire life, outdoors a lot, of course. I now see them twice a week if not more. Owls can be heard nightly, and in archery season I have had a few try to swipe my hat off my head while in a tree. We have a good deal more avian predators here than ever before in my life, cannot have zero effect, has to have some effect.

"Just a fact of life, in most species (except those that stay in groups, herds, packs, etc.) males wander farther and have a larger territory than females. Mink, marten, bobcats, lions, deer, coons, fisher, skunks; the males of all these species and many more, on average have a much larger territory than females."
Could just be during mating season. Im unaware of any hard data otherwise than the old method books saying "a male mink has a range of 20 miles". That was one hardy individual that did that tracking.

You might want to read some scientific facts/data in that Mink Habitat Indexing document I posted. It was the Project’s SOP!

Not to get off track of the mink topic, just a share of my experience with respects to owl predation on rats.

I have seen great horned owls snatch muskrats twice in my life while predator calling at nite. I am sure it was just a matter of being in the right place at the right time sort of situation.

One situation I was set up calling from some brush not far from a small farm pond. Looking at that time for some red or grey fox I knew were in that area.It was a good moonlite night.

As I was scanning the area with my wheat lite headlamp "what I used in those years" I caught a flash of movement from my right just long enough to see this owl swoop down and nail a muskrat that I hadn't seen at first.

The rat was just near the breast of the dam and not quite over the top of the dam for me to see it moving around much. I did see it as it flopped around under the talons of the owl once I focused on the event more closely.

The other was in Arkansas when doing some beaver control work at night shooting beaver with the Game and Fish Dept. along some Delta Areas. An owl came across the water along the shoreline and snatched a swimming rat at the edge of the bank just in the water. Those owls are some terrors of the night. That rat never knew what hit it.

Great info Mike.

I've seen redtail hawks along a local canal in the daytime with muskrats they had caught and were in the processing of eating. They would fly into some nearby trees when I passed but always came back to the carcass.

Scared off a hawk that had a mink pinned down once. The avian predators are everywhere these days. Any open water muskrat is living on borrowed time.