Back in early November, I woke up at the Niobrara Valley Preserve. (That makes it sound like I was surprised to wake up there. I wasn’t – I’d driven there the night before. Anyway…) I went for a sunrise walk on a hill where a prescribed burn had occurred a few weeks before.
Not surprisingly, there wasn’t much activity. The growing season was long past, there was a light frost on the ground, and a fire had recently swept across the site. I was mostly there because of the nice view of the river in the distance and to see how the fire had burned (I wasn’t there for the fire and was just curious).
When the sun popped over the ridge to the east, I suddenly became aware that I was surrounded by millions of silken strands, strewn across the blackened ground. I’ve seen this many times, usually in the fall, I think, and often in burned areas. I don’t think the phenomenon is tied strictly to burned areas, but the contrast between silk and ash makes it easy to see there.
Some of you might recall a blog post by Katharine Hogan during her time as a Hubbard Fellow a few years ago, in which she described a similar observation. She asked me what was causing it and I gave her guesses, but they were only guesses. After some research, she came up with some reasonable possibilities and opened the floor for others to chime in. I’m still not sure why this occurs, or whether there is a tie to autumn or recently burned areas, but I’m pretty sure it’s a mass ballooning event by spiders. Maybe they were leaving the area after the burn? Maybe they were spiderlings that hatched after the fire and were heading elsewhere? Maybe they were just spiders passing through on migration and the burned area simply made the silk easier to spot?
When I noticed the silk, I started walking toward the sun, looking for a way to photograph the way the strands glowed in that light. As I did, my eye was caught by a tiny movement. I stopped, foot in air, and backed up to look again. Kneeling down, I spotted a small spider crawling along a line of silk, dragging another line behind it. Again, this was within a recently burned area on a November morning with frost on the ground.
Well, I thought to myself, maybe I’ve solved the mystery! But looking around, it was clear there weren’t millions of nearby spiders doing the same thing. It seemed more likely it was an anomaly – a spider that had decided this was a good place hang out for a while and spin a web. I didn’t think there was much chance it was going to catch a meal in that web, but I sure intrigued by the attempt. I laid down on the ashy ground with my camera and tripod and watched it work.
While I was surprised to see the spider on a cold morning, it wasn’t a total shock. Way back in the first year of this blog, I shared a story about watching a juvenile wolf spider move around on a frozen stream on a much colder day. Here’s a photo of that hardy soul:
Eventually, I had to get up and start walking back to my truck (we were getting ready for another prescribed burn). Before I did, though, I managed to get a photo of the spider’s face, hoping that would help me figure out what species it was and whether this cold weather web-spinning was common behavior for its kind. The arrangement of the eyes on its face was typical of orb weaving spiders, but that wasn’t a surprise, given what it was doing. I still haven’t identified it, so if anyone happens to know, clue me in!
Whether this spider knew something I didn’t, or was building a futile web out of instinct or stubbornness, I admired its stubbornness and industriousness. Sometimes, when you don’t know the right thing to do, you just do what you can and hope for the best. I hope the spider didn’t need a meal to sustain it through the winter and that it built itself a silken winter shelter soon after I saw it. If so, there’s a pretty good chance it will be out there to spin a web again next spring, and if so, I wish it good hunting.