Sunday, March 15, 2009

Furry Sausage with Legs

After spending yesterday sequestered inside, finishing off various things WHICH MUST BE DONE, today was ripe for an escape. And that I did, on a big blue sky day, warm and balmy. At least by early spring Ohio standards. Signs of winter's end were everywhere and very much in my face. Tallied singing Western Chorus Frogs, Northern Leopard Frogs, Spring Peepers, and noted Green Frogs leaping desperately from the bank as the giant humanoid approached. Even some Painted Turtles basked on sun-soaked logs. A real treat was hearing the sweet lilting whistled songs of American Tree Sparrows, tuning up before they strike out for the land of Midnight Sun and Polar Bears. I also saw a few Tree Swallows, bold scouts back before the mobs of their brethren arrive.

Destination: Big Island Wildlife Area. This place sometimes gets overshadowed by the better known Killdeer Plains, seven miles to the north, but Big Island is even better. I had scads of birds here today, especially waterfowl, which were my main targets. At least seventeen species, and several thousand birds in all. Nothing unexpected, but this'll be a good place to watch for rarities such as Eurasian Wigeon in the coming week or so. There were plenty of American Wigeon, and it's in with those that the Eurasian will likely be. There were also a few hundred Green-winged Teal, and I knocked myself out looking for a Common Teal, to no avail. Gotta try, though, and definitely spend time looking through teal flocks for one with a horizontal rather than vertical white bar.

I noted my first Eastern Garter Snake of the year; a couple of sluggish baskers on one of the dikes. These chaps really need to shed those skins. When they do, they'll be bright and shiny as a new penny. Still looks pretty good, though - unless you are ophidiophobic.

I made time to stop by a Snow Trillium site scattered along rocky limestone woods buffering the Scioto River. Still a bit early for Trillium nivale; another two weeks and their creamy-white three-parted blooms will carpet this place. I did find one early bird jutting from the leaf litter and in bud.

It always pays to abandon the auto and head out on foot. One sees so much more. I made about a two mile loop around the dikes at Big Island, and was delighted to find this Lilliputian beast. Unfortunately, it was dead, but this Meadow Vole's misfortune becomes our learning experience. Small rodents like this are very high-strung, with a metabolism that whirs like a Lamborghini going flat out. I wonder if he saw me and I gave him a heart attack. The body still felt warm; he couldn't have perished more than a few minutes before I arrived on the scene.

Meadow Voles, Microtus pensylvanicus, are mice-like and probably often thought to be mice, as a flash of tiny brown fur is generally all one sees as they scamper through the grass. They are considerably heftier than our two species of deer mice, Peromyscus, though, weighing nearly double. Voles truly are furry sausages, and that's probably how raptors think of them. This is a very common prey item for Northern Harriers, Rough-legged Hawks, Short-eared Owls, and other birds of prey that hunt open fields. Like most small mammals, Meadow Voles have boom and bust years, and their peaks and dips have a direct effect on how many wintering raptors are present in a given area in winter.

Cute little buggers. Unlike White-footed Mice (now known as North American Deer Mouse), voles have tiny eyes and appear earless. You see any ears on this guy?

Now you can. The ears are actually quite large, but covered by dense fur. I imagine voles hear quite well.

Meadow Voles also have stubby little tails, unlike the longer appendages of mice.

Voles are primarily herbivores, eating grass, clover, and other succulent greenery. Those incisors look pretty impressive, but you are seeing both the upper and lower set almost straight on.

Meadow Voles make exensive runways, which are tunnels through the grass. I knew a runway had to be close at hand when I saw the vole, and sure enough, there was. So I posed the vole within, and if he were alive, you'd pretty much just see a flash of fur as he booked along, partially concealed by the grasses. This is what those harriers and other raptors are looking for as they quarter over the meadows. Studies have shown that vole urine produces chemicals that are visible deep into the ultraviolet zone, and that birds of prey can thus see the trails left by voles. Therefore, raptors can quickly ascertain if many or few voles are present in an area, without having to see the actual animals.
By the way, if you'd like to learn more about mammals, I highly recommend Kenn Kaufman's field guide, Mammals of North America. It's the best, most up to date book out there. I'm just sayin'...


Lisa at Greenbow said...

Now that title really caught my eye. tee hee... I was wondering what you considered a furry sausage. I have had these little critters in my garden. They go under the leaf litter and they also squeak at me when I sit on the patio.

I have really enjoyed your salamander hunts. I didn't know some got so large.

Tirilliums are up here too.

Jared Mizanin said...

Nice post; I never really took a close look at our raptor's favorite food! But I must ask, have you ever seen the newest Peterson guide to Mammals, done by Fiona Reid? Completely different from earlier editions and definitely worth a look.

Kaufman's, yes, is very nice as well, and includes photographs of species I hadn't ever seen before...and collectively the Focus guides are among the most pleasing field guides to just flip through. I actually bumped into Kenn at Metzger Marsh and asked if he was doing a reptile/amphibians guide...but I don't think that is in the works :(

Jim McCormac said...

Thanks for the comments! I agree, Jared, that Nat'l Aud book is fab, and has lots of great info about each species. Got a copy on the shelf!


dAwN said...

What! you gave tha poor vole a heart attack? LOL...are they really that sensitive? I think the critter needs a tooth brush..very yellow teeth.