Video vision in the tunnel - Part 2

Our first attempt at subterranean video this year was disappointing.

Had the camera been placed differently the footage could have been better, but there was also the problem of the curious bear cub that dismantled the set.

The subterranean action however was more than enough to call us back.

Our second attempt in August was in a different segment of the same mountain beaver (=showtl) tunnel.

This time I came prepared with a customized mount that could be spiked into the hardpan on the floor of the tunnel and nailed into the log embedded in the silt bench above the tunnel.

Set 519.3 after being disguised
with a large flake of red fir.

The camera post was spiked and wired
to the embedded log. 

We covered the vertical hole with a large flitch of wood.

As you have seen in Part 2, the bear didn't show, and if any subterranean critters bumped into the camera they didn't move it.

















But I still didn't get the angle of the camera quite right. It should have been aimed up into the tunnel. The focus was also off, and the microphone made hideous sounds (which I'll try to remove -- sorry about that).

The camera in situ as we uncovered it
33 days later.

I just replaced the lens of the DXG 567v with a 4mm wide-angle CCTV lens, which will take in a much wider view.

We'll try again next spring.

Long-tailed weasel and rodent cornucopia

A long-tailed weasel (Mustela frenata) checks out the castoreum stain left as a scent lure.

Yuba River (North Fork) drainage, Sierra County, California

I wasn't expecting miracles at set 574, but it always seems like a miracle when I camera trap a weasel. Especially a blue-eyed weasel. (Just kidding, folks; those pretty blue peepers are the reflection of the camera's flash from the eye's tapetum lucidum).

This weasel sniffed the castoreum just long enough for a single photo.

The set was under a boulder on a steep slope in red fir forest.  A few de-scaled pine cones identified it as an undercover messhall.

The camera snapped 431 photos in 33 days, but 60% were blank images most probably triggered by fleet-footed rodents.

Long-eared chipmunk (Neotamias quadrimaculatus)

Possibly a brush mouse (Peromyscus boyleii)

Deer mice and long-eared chipmunks accounted for most (=80%) of the wildlife photos.

Long-tailed vole (Microtus longicaudus)
shows its bicolored tail

A bright-eyed long-tailed vole posed nicely for one photo,

Northern flying squirrel, a meat eater. 

and northern flying squirrels left 13 images during three visits.

Chickaree (Tamiasciurus douglasii) 

Chickaree's visited 10 times and left 14 photos.

Even the deer mice sniffed the castoreum.

Every species of mammal left at least a few self portraits while sniffing the irresistible castoreum.

The stuff is a truly broad-spectrum attractant for mammals and indispensable to this camera trapper.


I can't identify the only critter that ignored the scent lure.

The best of three photos of the "mystery chick".

At first I thought it was a scruffy molting wren.

But now I wonder if it's a chick of a blue (sooty) grouse, mountain quail, or even a sora rail?

Early September would seem a bit late for a chick, no?

Any opinions out there?

A hold out from the Pleistocene

Long-tailed vole photographed by Jake Kirkland during the Camera Trapping Workshop in July 

The long-tailed vole (Microtus longicaudus) is a nonconformist.

Unlike most other Microtus it is not a highway engineer -- it doesn't seek out lush pastures to make runways, zip back and forth gathering forage, and obsessively trim any intruding plant growth.

It's a vole of mountains, forests, and sometimes sagebrush.

Though it lives where there are plenty of wet grassy meadows, it prefers wooded habitats like this thicket of mountain alder between the Yuba River and red fir forest.

The modus vivendi of the long-tailed vole was shaped by the cool wet weather of the Pleistocene, which  is reflected in its distribution from southern Alaska to Arizona and New Mexico.

That may also explain why it thrives in disturbed areas -- fire, clear-cutting, and surface mining affects vegetation just like earth-moving glaciers.

In the arid lands of the southwest it is holding its own on "sky islands" -- mountaintop habitats that resemble areas farther north.

During the ice age the southwestern part of the US looked more like Canada today, but that started to  change when the glaciers melted.

So the cool breezy heights of the intermontane west are remnants of how it used to be, and refugia for hold-outs from the Pleistocene -- like the long-tailed vole.


References

Wilson, D.E. and S. Ruff (eds). 1999. The Smithsonian Book of North American Mammals. Smithsonian Institution Press, Washington, D.C.

Ingles, L.G. 1965. Mammals of the Pacific States. Stanford University Press, Palo Alto.

Verts, B.J. and L. Carraway. 1998. Land mammals of Oregon. University of California Press,  Berkeley.

The little guys who also show up

These are pictures of "incidentals", the little guys who also show up. Aplodon was my target species at this set, but there were several passersby in the vicinity of the rodent's burrow. I tentatively identified the creature above as the water shrew (Sorex palustris), and the brown-colored one below, if you can see it, I am tagging as the vagrant shrew (Sorex vagrans). As I mentioned though in the workshop summary (a couple posts back), these are tentative identifications.



Three of us photographed long-tailed voles (Microtus longicaudis). They were all filmed moving about day and night in the alder thicket.



Of the birds, this yellow-rumped warbler is unmistakable. The other photo of it revealed fewer diagnostic features.



Though wood rat pellets and cached cones were abundant in the granite recess of the following camera set, the mouse was the only visitor. It could be a North American deer mouse (Peromyscus maniculatus) or a brush mouse (Peromyscus boylii). Based on coloration (not well rendered here) I am guessing it's the latter. It was photographed at 6000 ft on a large cliff face near Yuba Pass.