I don't have good data on fisher. There were none in Alaska except on the mainland in southeastern, and populations are not legal for trapping in Idaho. These data I gleaned from carcasses that belonged to Idaho Fish and Game from carcasses that were turned in by trappers.

I've caught a few fishers incidentally while wolf trapping. I've never targeted them.



The skulls are easily sexed. Only the males have well-developed sagittal crests. The near one is male; the back one is a female.



Young-of-the-year animals can be determined by the growth plate (the hypophyseal/epiphyseal symphysis). Juvenile on the right, adult with fused bone on the left.



Adults can be sexed easily by size alone. These are femur bones of a female (on top) and a male (bottom). Both are adults.


See the small bump on the far femur and the hole on the near one? This tubercle can be used to determine age also. The far (top) one is an adult and the near femur (bottom) is from a young-of-the-year animal.


Like marten, fisher can be managed by avoiding capture of high numbers of adult females. It is useful to be able to accurately age and sex the harvest for better management. Hope you enjoyed this weeks' Photo Phriday!

Interesting

Thank you Jack, the difference of male/female skulls is quite a difference. No wonder the big males have those dome heads that I like to see.

Here are my shares. The first one is a very rare type, a cross between a fisher and marten. Very few people have ever seen one ... as far as I know, I am the only one who has attempted to draw them.

You can see by my profile pic how much I love fisher.

That would be interesting.Fisher prey a lot on marten.Then again wolves kill coyotes but in some instances coyotes have bred with wolves.

Thanks for info Jack, learned a bunch...

Bruce, it is a joke. I was being subtle on that...sorry ...it was an old story , of fiction, that I illustrated for a magazine a long time ago.

Great info on fisher Gulo.
The bio here referr to big male fisher as "Appleheads"

That's the exact term I've used for decades with the old, male marten.

Gulo, cool info! I like learning stuff.

Sharon, I believe I remember Hal S. writing a bit about the Fisher/marten hybrids he called "Farten". Hal's powers of observation are legendary! As always, your sketches are fantastic renditions.

That's interesting Bruce. Can you point me to the data on that predation and how it was collected ?
Thanks !

Tow headed is the term

Jack: what is the biological reasoning behind the lack of a saggital crest in the females ? I assume the muscle attachment points are the same in both sexes .....NO ?

When I first started chasing marten and fisher (not that long ago compared to some of you), that is what I read and was told and also that they typically run in different habitats/areas. One won't tolerate the other. Like yotes and wolves. Last few years, I've seen sign and caught them in overlapping areas that shows otherwise.

Right out the bathroom window !

They don't shy away from neighborhoods

Excellent memory, JM. Yes that was the article. Actually there were a few of them. I got tired of the phrase " and no one to this day has ever seen one", so I decided to pop that bubble . I saw them myself one day. Having a good old time out in an open wooded place deep in the mountains. I think the brew they were enjoying was a combo of Blue Moon and orange juice. The hybrids were perfect crosses of marten and fisher. From the fisher- bigger bodies , but not as large as fisher, the longer, pointed tuffed tails, the apple ( or is it Mac?) heads... From the marten, the great necklace bling, nicer ears, and wolverine-like paws.

The author of said articles didn't want me to show what they really look like. But I used his own philosophy right back to him. He told me long ago, that he loves to huff at editors, telling them what he writes is it....no editing. No telling him to change something. Leave his stuff alone. I quoted his words back to him, finishing with Judge Jeanine's words, " and that's what I'm gonna say about that".

One of my editors, a well known fisher trapper, absolutely loved them, expressing in detail the nuances of the illustrated hybrids that he liked. THAT was all the permission that I accepted .

Marten, fisher, and hybrids have a thing in common. They all love their brews, music, and entertaining stories.

That is correct.I catch both marten and Fisher in the same areas in the same traps a lot.Have had Fisher eat marten out of my traps and caught the Fisher the next trap set.

The data on Fisher killing marten was from me trapping Fisher and marten on my own trap lines for years seeing where Fisher ate marten from my traps confirmed by evidence in the snow(tracks,ect.).Most times I would then catch the Fisher on my next trap visit.I have also seen Fisher chasing marten.

Very interesting