Monday, April 28, 2014

Northern Short-tailed Shrew Nest, Latrine and Cache

Greetings everyone! I have been slow to blog in 2014 due to a very busy schedule. This weekend's wildlife encounter forced me out of exile and back into the blogosphere. On Friday evening, we hosted the FLCC Student Chapter of The Wildlife Society for a nice spaghetti dinner (thank you Laura!) followed by a woodcock walk on our property. We checked for tracks in muddy spots, looked at muskrat lodges in the wetland, learned a little about native warm-season grasses and tried to find spring peepers in the pond. But one of my highlights is always flipping over some old pieces of siding to see who might be living underneath.
Short-tailed Shrew
Seneca Falls, NY (4/14)
I should explain that I have been a "flipper-over" for a very long time. I saw my very first weasel when I was a teenager by looking under an old sheet of plywood. I found my first Norway rat under an old automobile hood. Childhood successes such as those made me a life-long investigator of all things flip-able. So I was very excited when our first piece of corrugated siding produced a short-tailed shrew. One of my students caught the shrew and I held it for all to see. Sasha (club adviser and FLCC Technician) noticed a nest and we concluded it was the shrew's. It was empty.
On Sunday, my wife and I took a walk to look for antlers and decided we could risk disturbing momma shrew and flipped the siding again. We waited patiently and within a few minutes, the shrew began to nose around at her newly disturbed world.
Molting short-tailed shrew
Seneca Falls, NY (4/14)
In the photo above, you can see a bit more of the shrew and she is clearly molting out of her winter coat. I guess it makes sense, but I honestly never thought of shrews molting before. Notice how small the eye is. Shrews are not known for having good eyesight. She slowly emerged from her tunnel and made her way into the grass...
Northern short-tailed shrew emerging from tunnel
Seneca Falls, NY (4/14)
There is the short tail that gives this species of shrew its common name.
Seneca Falls, NY (4/14)
I decided it was worth it to peek into the nest. I have only ever found one other shrew nest and blogged about it here. But if there were shrews in this nest, they would be less than two days old. We carefully peeled back the dried grasses to find a ball of leaves. And inside the leaves were eight tiny altricial shrews.
Baby shrews in nest
Seneca Falls, NY (4/14)
Look for five digits on the front foot to rule out mice
Seneca Falls, NY (4/14)
Baby short-tailed shrews in nest
Seneca Falls, NY (4/14)
We carefully covered the babies and I quickly snapped a few photos of the other items under the siding. There was a large pile of scat within a foot of the nest. I cannot imagine it was made by any other species (especially given how fresh some of the scat was). However, the diameter seemed rather large when I compare it to published information. Elbroch says up to 3/16 inches in diameter and although I did not measure the scat, it sure seemed larger than that. He also states that when they are feeding on worms or other soft bodied animals, the scats would be "soft squirts". Well, that certainly describes the freshest of the scats. Here is the latrine:
Short-tailed shrew latrine
Seneca Falls, NY (4/14)
Short-tailed shrew latrine. This is the end that was closest to the nest.
Seneca Falls, NY (4/14)
The piece of corrugated siding was about four feet by three feet. Besides the nest and the latrine, I noticed two spots with concentrations of earthworms. Now, this entire area was bare of vegetation, yet the only earthworms to be seen were in two small areas. They were alive but slow moving. I have to believe they were cached by the shrew. Have a look:
Worms cached by short-tailed shrew
Seneca Falls, NY (4/14)
I wonder if the worms had been injected with some of the venom these shrews have in their saliva. That would explain how they could be cached alive. The large one near the top of the photo looks damaged.
I hope I did not disturb her too much but I learned a lot from this encounter. Latrine, cache, nest.... it was all here! I will check again after the young have left the nest and see what else I can find.