Where have all the critters gone?

Something's odd. The house this winter has been unusually critter free.* I have seen no sow bugs for a couple of months; they used to patrol my windowsills regularly. The big spiders that preyed on them are gone. I've seen three or four micro-dot spiders in as many weeks. No flies. No stray beetles. No crane flies, moths, or mosquitoes. Not even any of the Western conifer seed bugs that usually seek out warm houses for the winter.

Yesterday, I brought in a handful of soil from the garden, and examined it with a lens. There were no pill bugs. No spiders. No springtails, even.

Looking at that last paragraph, I said to myself, "That can't be right!" So I went out and collected another handful of dirt, and looked at it under a bright light with the lens and then the hand microscope. I found two slug eggs and one lonely springtail. No mites, no worms, no mini-spiders, no globular springtails, no sow bugs, no tiny snails.

I don't know what has caused this. Not the weather; inside, there's heat. Outside, it has been freezing and everything burrows down deep, but it's been warmish for some days now, and today the sun is shining on the soil I collected; it should be swarming with happy life.

I found my first spider** of the year, though. Yesterday, the 22nd.

Just a baby still. About 2 mm. long.

*I checked my photos for last year, Dec. 2015 and Jan. 2016; I had spiders inside and out, including a batch of spiderlings, tiny snails, and a ladybug. And I remember chasing crane flies all over, but never getting a decent photo. I was feeding sow bugs to the mother of the spiderlings. The cat was busy tracking big, black beetles around the baseboards. So the critters were still here, still active even when it snowed.

**That is, first spider big enough for the camera to be able to see. It doesn't glom onto biological motion the way my eyes do.