So you think you can ID apodemus mice? (1 Viewer)

[opisska]

Some time ago, there was a discussion about apodemus mice ID and some claimed that you can ID Wood from Yellow-necked even without seeing the neck.

I realize that this theory can be put to an interesting test by showing you photos of mice where we reasonably think we know what it is (thanks to other photos of the same individuals), but the photos itself do not really show the neck. I have picked two such photos and one "fake" which is just cropped above the neck, for the lack of any "correctly bad" photos of the same mouse.

So are there any people brave enough to give judgement on those?

 

[Sangahyando]

I'm not an expert, but the huge ears and the seemingly white (not greyish) underparts lead me to believe these are most likely YNM. However, it would be easier if the tail were visible. From what I've read though, the most reliable method is to get the measurements of the critter.

 

[opisska]

I'm not an expert, but the huge ears and the seemingly white (not greyish) underparts lead me to believe these are most likely YNM. However, it would be easier if the tail were visible. From what I've read though, the most reliable method is to get the measurements of the critter.

What would you look at regarding the tail, length? That seems to overlap - even though a very long-tailed individual would be quite surely YNM, for a lot of them it doesn't seem very useful, if the published ranges for length are correct.

 

[Farnboro John]

What would you look at regarding the tail, length? That seems to overlap - even though a very long-tailed individual would be quite surely YNM, for a lot of them it doesn't seem very useful, if the published ranges for length are correct.

The proportions look different as well, though: YNM has not only a very long tail but quite a thick one whereas a Woodie's tail looks thin along its full length from the base.

I also think photos 1 and 3 are YNM but I'm less certain about 2 because the eye looks bigger in proportion to the head than in the other two pictures and the back looks less orangey and more brown - though that could just be the lighting conditions.

A good test, but the points made previously included that if you couldn't see the neck then you do need a good view of important other features including the full tail. Also, in the field YNM is just massive! :t:

John

 

[MarkHows]

For some individuals you can ID YNM, if there is a particularly long tail as already discussed or if you have some idea of size, I have caught some very big YNM one was 49g so easily twice the size of a large wood mouse.

So I would say that sometimes you can ID them and sometimes not. In the UK we have it easier as YNM are only found in the Southern parts of the UK so large areas only have wood mice.

Mark

 

[opisska]

These are the same three mice in photos which to me seem more telling. To me it seems pretty clear that the first one should be Wood and the other two YNM, because the breast patterns look visibly different.