I had an interesting conversation the other night with a person that used to trap in the 80's-90's. Northern WI both of us one Eastern myself Central. He asked in the early 70's to 80's we had way more trappers and muskrats, mink, beaver were abundant. Today we see less rats, mink, and beaver. With far less trappers today. So with higher trapper numbers and furbearers everywhere then, why with less trappers do we seem to have less beaver, muskrat mink? Couple old timers around here agree with the numbers thing as well. Thoughts?

I think the decrease in rats and mink might be due to the increase in otter numbers. I think the decrease in beaver could be due to DNR contracting APHIS to remove every beaver from entire watersheds connected to trout streams.

I would suspect habitat. Swamps are choked out with invasive cattail, rats no longer thrive in it. 4x4 tractors and drain tile have remove a lot of small wet spots in fields, large excavators getting cheap has been the undoing of the tree lines. As the farms have grown and farmers less connected with their land they've maximizing production and not really noticing the birds or animals are gone

I think this is the main thing, I would add to it that I think farm chemicals are changing the environment for the worse, I think a lot of the things the muskrats feed on have been killed and of course with fewer muskrats you have fewer mink. A lot of drainage ditches and small marshes that used to be full of muskrats just don't look the same and the rats and mink numbers are way down or gone altogether in a lot of places.

There also weren't red-tailed hawks on every telephone pole back then either........

Undertrapping is more detrimental long term than overtrapping.
I have been taking the same amount of beaver every year from several traplines over a period of 40 years.

Haven't their been numerous studies done on the decline of rats? I would think ag chemicals would be one of the easier influences to to test and determine. Do rat populations ever get to high levels in places that still have good habitat for them?

In Pa, muskrat numbers are a fraction of what they once were. But mink numbers appear to be up. There’s beaver here, but not many. Compared to the states north of us, the beaver population in Pa never was great.

In the high dollar coon days, the population was really got throttled back. Today, they’re everywhere.

Don't know about rats and mink but those hawks sure seem to be hard on our ground nesting birds. We saw a large decline in hawks in our area several years ago based on the effects of bird flu im guessing and our quail, rabbit and pheasant population has rebounded a noticeable amount

Phragmites are the killer of muskrat numbers here imo

Excellent question. I've wondered the same thing. Thanks for asking. I don't know either. I'm sure habitat loss, combined w/ increased invasive species have played a role. I wonder if eagles eat muskrats.

Eagles eat lots of muskrats when the ice starts to go out and the rats sit on the ice edges to eat.

X2 - habitat destruction.

I’m old enough to have seen what the increase in aerial predation has done to the rat & mink population, that’s not discounting the otter. In my watershed we’ve got a super fund project up stream for decades with DDT & PCB contamination. You played the devil to see a hawk or owl and never an eagle and rat numbers were high (not mink) BUT that had all changed in the last 20 years from when the DNR wanted us to call in any sightings of Bald Eagles because there were so few. Now, Bald Eagle sightings are or can be a normal daily occurrence, same with hawks!

Part of the MSU Dioxin Prj was Great Horned Owls. Man-made nests were hung along the 42 miles of the “river of concern” and samples were takenevery spring for their pellets AND from their nests while taking blood samples from the fledglings. These studies were from nest within 100m of the river! So, a habitat negative for rats & mink has to do with them as prey from arial predation!! Tall trees equal arial predators!! No trees to short trees does not afford arial predators optimum prey(rats & mink) habitat!

I have lived my entire life within the watershed as I’ve described. I remember when I was a kid when the rivers were so polluted that they stunk BUT the rivers and banks look exactly the same today as they did back then. I mean how much does a Cottonwood tree grow in 79 years when they are already big trees??

I want to remind those reading my reply that during the 3 years I trapped mink for the Prj, laboratory testing of mink stomach samples showed that 81% of the stomach contents were aquatic animals , the balance mammalian and others. Think about it!

We studied and rated the mink habitat along the “river of concern” with an instrument designed to determine canopy cover which is in direct relationship to Ariel predation of mink(which surely includes rats). The more tall canopy cover the poorer the mink habitat, easier for ariel predation to occur! I worked with the study group doing this testing. Every 500m of river then skip 500m for 42 miles we would use the instrument to determine canopy cover every 10m for 100m inland. Since I did all of the mink trapping for the Prj I can say that my mink catch or lack thereof in sections of the rivers coincided with the readings we obtained from that study. Some stretches of river were not good mink habitat and others better(fewer trees and thinner)!

Think about the mink & rat habitat of waterways of other States that have little to no canopy over waterways and what the mink & rat catch numbers are in relation to waterways with a consistent 60’+ tall canopy!

Seldom, that makes sense too when you consider that areas that DO still have good rat populations, like the SD sloughs..... don't have a ton of trees.

Absolutely correct!! What they do have with no high canopy for perching ariel predators, they have plenty of sunlight coming to the ground so they probably have a heavy, waist high canopy, perfect for mink! Perfect for ariel protection for the mink & rats and perfect for mink’s prey habitat!

I agree, except it's not cattails that's the problem.
Cattails grow tubers under water, that the rats would feed on.
The crap grass ( I believe it was spread by people wanting tuffs of it at the ends of their driveways.
Very invasive , taking over pond edges and the roots are thin and not much food for the rats.
It's everywhere, didn't see it in ponds or swamps until the 90's .
It pushes out the cattails.