Spider eating a spider

Sue and I often stay in the Pacific Northwest Experimental Station out near Riley, south of the Burns Highway, to get a good night's sleep. After 10 hours and more of exploring the wilds of Harney and Lake counties, searching for golden eagle nesting sites, bumping over what some call "roads," in our ancient 4Runner, we usually pull into the station between 8 and 9 p.m., pooped, ready for a quick supper and then hit the sack.

That last time we were there, I had s-l-o-w-l-y carried the cooler out of the 4Runner and set it down on the kitchen floor, and as I was straightening up (rubbing my sore back and tired posterior), I happened to see two specks near the baseboard, just above the tiles covering the kitchen floor. Curious, I stepped over, and what do I see before my tired old eyes but two different spiders in a web. Uh-oh!

As I bent down for a closer look, I could see that one of them, the larger, a male, wasn't moving and had lost two legs, while the other, smaller spider was tugging on one of them.

"Holy cats," I said to Sue, "I think I'm watching a juvenile black widow eating a male sheet-web spider."

And with that I trotted (well, walked) back out to the 4Runner and got my camera.

For the next hour I laid on my belly on the kitchen floor photographing the action-tiredness and hunger gone-until Sue said, "I hate to drag you away from that adventure you're watching, but supper's ready."

After a hearty meal I was into the "hit-the-sack mode," and left the spider activity until morning. Of course, in the morning there wasn't even a wisp of silk left where the slaughter had been going on.

But I was really thankful I had the opportunity to catch the action when I did, a sight that you don't see very often: a juvenile female black widow polishing off an adult male spider - a first for me.

In the photo you can see some of what was going on; the large male sheet-web spider is suspended in the black widow's tangled web. She has apparently already killed him with her venomous bite, removed two legs and is about to eat one of them. "Eat" is not the correct term for what a spider does to "ingest" the body of its prey.

Spiders do not possess a "mouth" like most think of, with jaws and teeth. There are no jaws with which teeth are contained in spiders; there's just a hole where the jaws should be. (What some think of as "jaws" are really the fang-supporting chelicerae, pronounced kuh-lis-uh-ree).

The spider coats (and/or injects) the food/prey with venom via the fangs, which then turns the object to a liquid which the spider sucks into its innards through that hole-for-a-mouth in the thorax.

Male spiders, once they've made up their mind to go a-courtin', are hard to convince otherwise. The one in the black widow's snare may have been all set to go, stumbled on the young female black widow's web and may have thought, "Hey! Why not?" It was a fatal error.

Black widows are an ambitious species. I've seen fresh mice and dried-out rodent skeletons in their snares, along with bird parts, flies, beetles of all descriptions, meal worms, grasshoppers, moths, scorpions and other such victims.

Males are always far smaller than females of their species, some more than 60 percent smaller. The only time I can remember witnessing a male courting a female was ages ago when I stumbled upon (almost literally) an adult female writing spider, Argiopde aurantia, in her silken orb and a tiny male plucking away at the outer strands, whispering cautiously, "Yoo hoo! Here I am..."

I decided to stay with it even though I was told it would take quite a while for him to get to her without being eaten. After all, anything that moves those silken strands in the orb means only one thing to the female: food! Therefore, the process must take time; after all, he has to take a position directly under her to place sperm inside her, which he does with the aid of his boxing-glove like pedipalps.

One of the most exciting spider battles I ever witnessed was an adult black capturing and eating a bigger animal at OMSI's Camp Hancock many years ago. A small group of campers were looking and pointing under the camp's elevated fueling tank, cheering and jeering, and I went over to see what it was all about.

An adult Rufous hummingbird was caught up in the black widow's tangled snare, and each time the spider came out of her hidey-hole to give the hummer the coup de grâce, the kids would jeer. But when the hummer fought her off and she went back to her shelter the kids gave out a loud cheer.

Eventually the hummer got loose of the spider's strong web and flew off to safety, exhausted, and the folks in Fossil must've heard the kids cheering!