Sunday, December 18, 2011

Glimpses of Goodness

Speaking of Mono Basin sagebrush voles - a cam did, in fact, get a glimpse of one.

But only 1 glimpse.

sagebrush vole
Shy sagebrush vole giving the camera a suspicious glare

Funny thing - it just happened again, when I tried to short-set what I think are montane voles up in the western Sierra Nevada foothills.

The burrow was obviously active, but the cam only caught a single shot in 3 days & nights:

montane vole
Shy montane vole also playing peek-a-boo

I'm not exactly sure why they're acting shy, but I have a couple of hypotheses:
  • voles are commonly hunted just outside their burrows by ambush-style predators, such as bobcats and coyotes, so are sensitive to the addition of an object that looks like it could be a waiting fang-forest. I.e., it might take longer than a few nights for them to habituate to a cam, and I might want to disguise it better.
  • my smelly seeds aren't impressing them. Sagebrush voles evidently don't eat seeds often, relying mostly on sage and rabbit brush leaves, flowers and cambium for their diet. And the montane vole eats grasses, sedges and flowers. 

So, I'm going to have to change tactics in 2012 to get some good photos of these characters.

But that's ok, I have a feeling that, like the mighty minimus, they'll be worth it.

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3 comments:

  1. This post made me think of some of my attempts at camera trapping rodents…

    I recall one set where the resident rodents were clearly aware and cautious of the camera at first, but their confidence grew over the next couple of nights.

    There was another set just (after a fire) where the burrow users would spend much more time sitting in the entrance of the burrow than I would have expected. There are also some great photos of them peeking over the edge and scouting the area for danger. The little guys might have been more anxious because of the sudden loss of cover after the fire.

    A possible theory: Did you clear away any cover (twigs, leaves) when you placed the camera? This loss of cover in conjunction with the sudden appearance of the camera might persuade some shyer rodents to be careful and use another entrance instead.

    You might be right that your sent and the unattractive food might also play a part. Maybe this wasn’t a frequently used burrow to start with?

    Interesting stuff :)

    A great post as always and please keep us informed if you find out more.

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  2. Good observations and thoughts Henry. I didn't really move much around at the sets (for fear of that disturbing them). It's likely the sets just need more time. I'm sure seasonality comes into play too - if the little guys were hungry, I'm guessing the cam might not bother them as much. And, it might be too few data points - maybe I just caught a couple of shy ones. :)

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