The Bugs in the Backyard: Walking in a Winter Wonderland of Unexpected Arthropods

We had a blizzard Monday. This is what the woods look like these days:

This photo was taken with my cellphone, but I did bring my real camera into the woods today. It had the macro lens on it, though, so it wasn't ideal for taking a landscape photo. It's two days since the blizzard and the temperature today was close to 40ºF. I went on a bug walk in the woods for a specific reason: yesterday when we went snowshoeing in the woods I found some snow fleas, and I wanted to take pictures of them, but a cellphone is really no good for that, because snow fleas are tiny, so tiny that if you saw them, and they weren't moving, and you didn't know what snow fleas are, you would probably not even realize that they are living creatures. So, today I figured I would walk out to where I saw the snow fleas and they could be Backyard Bug of the Day. They are certainly not a new species for me, but strangely, in my regular backyard I hardly ever see them on snow. I see them on tree trunks and rocks, but only on a few occasions have I seen them on snow. And yesterday was my first sighting of them this winter, I think. So, seeing them on snow yesterday, I thought it would be nice to get those shots, and I was fairly certain that I would be able to find the snow fleas in the same spot today. The tree where I saw them yesterday is just about as far from my house as you can get in my woods, almost to the far border of the property. I arranged my day so that I would have time to walk out there during the daylight hours. I have no idea what snow fleas do at night, but daylight was definitely going to make taking photos easier. So, I set out with my camera, planning to walk all the way across the woods, and scarcely had I entered the woods when I saw snow fleas on the snow right on my path. Lots and lots of snow fleas. Probably more than I have ever seen before. They were all spread out; I didn't get to see a huge, tight mass of them, as I have sometimes seen in photos, but there were an incredible number of them. So, I didn't really have to walk far at all–I took some pictures, and told myself that I had what I had come for... but... I like walking in my woods, and I need the exercise every day, and even though I was on a time crunch today, I had given myself enough time to walk out to that far tree... so, I decided to continue on and visit the tree anyway. And it was the most amazing bug walk that I have had in... well, I haven't done a bug walk in a couple of months, but this was a better bug walk than I had in month before that. Snow all over the ground, completely overcast day, and there were bugs everywhere. First, there were the snow fleas. I probably walked just under a mile, and covered acres of woods, and for a huge proportion of the space I covered, there were snow fleas all over the ground, like someone had walked through the woods with a pepper shaker in each hand, sprinkling pepper on the snow. But it wasn't just the snow fleas. The number of species of insects–and other arthropods–that I saw today was shocking. Mind you, it's February, and there's snow all over the ground; we're not talking dozens of species. But... well, let's just get to it...

Backyard Co-Bug of the Day #1:

Snow scorpionfly. This is a new species for me; I didn't even know such a thing existed. I am proud of myself, though, for having noticed how much it looks like a scorpionfly; I thought maybe it was a scorpionfly nymp, not knowing if they have nymphs or larvae. But no, this is an adult snow scorpionfly. Recognizing the resemblance made it easy for me to find out what it was by looking up scorpionfly nymph online, and then I looked it up in my bug books, and actually found it in two of them. Huzzah! I learned so much today!

So, here's what I learned about this gorgeous, little insect: first, obviously that a snow scorpionfly exists. When I thought it was just a scorpionfly nymph, a summer species, I figured it had gotten dislodged from wherever it was sheltering for the winter, but no, it's normal for these to be out on the snow. I began to figure that out when I found more than one of them today, and not near each other. It seemed like an extraordinary coincidence that three of them would happen to have been knocked out of whatever treebark crevice they were hiding in for the winter and landed on my walking path. So, according to Kaufman's Field Guide to Insects of North America AND Insects of New England and New York, it's normal to see these on snow "In late winter or early spring." Well, it's mid-winter, but whatever. Both books also mentioned that they feed on moss, including in their larval stage, which makes me wonder if the tiny larvae I found in some moss a couple of years ago and was never able to identify were larval snow scorpionflies.

This, by the way, is a female.

This one is a female, too. And how do I know that? Well, that pointy end does look like an ovipositor, but that's not how.

I also learned about sexual dimorphism in snow scorpionflies. Female snow scorpionflies don't have wings...

... but males have tiny (not flight-capable) wings that are used in mating. So here's a male...

Note the tiny wings.

I also learned that when they want to avoid predators they curl up and try to look like a piece of dirt (according to Insects of New England and New York):

It's not super effective if your predator, or in this case, photographer, sees you do it... or, maybe it works just fine with predators. It didn't work on me.

Backyard Co-Bugs of the Day #2:

Snow fleas. Like pepper on snow. Pepper that jumps around.

Snow fleas are not fleas, they are a species of springtail. Depending on your source of information, they are not even insects; Kaufman's Field Guide to Insects of North America says, "Springtails are now considered 'non-insect hexapods,' or even placed in their own class..."

The book also says they are among the most abundant invertebrates, and today I could definitely see why.

These are not the only species of springtails I saw today, either. I saw two more species:

One of the reasons that I continued on my walk today was because I wanted to look on a tree where I have been seeing winter stoneflies in the last month or so. Before the blizzard we had several days when the temperature was below freezing both day and night, and so I wasn't seeing stoneflies, but I thought since today was warmer I might find them. Well, I didn't have to look on that tree, because I found them all along my path, crawling around on the snow. There were nowhere near as many as the snow fleas, but I saw more stoneflies today than I think I have ever seen.

I did check on the trunk of that tree, and I found one stonefly. Not so surprising that I didn't see more; the stoneflies definitely preferred walking around on the snow today.

At the foot of that tree the snow was covered in snow fleas, and I also found one of the other springtails and my first snow scorpionfly. A few square feet of forest, so many species of arthropods! And that's not even all of what I found today!

I mentioned that we had several days of freezing temperatures; during those days parts of the stream froze over, mostly the pools where I have been seeing water beetles and caddisfly larvae. The ice made it harder to see under the water in most spots, and I didn't do any night hikes, so I didn't get to see if they were active after dark (which is when I normally find them). I have been curious about how cold the water can get before they are no longer active. I did see a few caddisly larvae on one of my hikes on those cold days, but I did not see them move at all. Since the blizzard it has warmed up a little bit, just above freezing yesterday, and several degrees above today, so the ice on the stream is mostly gone. I saw this caddisfly larva in one of the pools. It was too far from the bank for me to get a closer shot, and I didn't see it move at all in the minute or so that I watched it. But at least I saw it.