What's for dinner?
A crab spider, camouflaged in our lavender patch, didn't catch a honey bee, a butterfly, an ant or a syrphid fly.
No, it nailed a green bottle fly.
We couldn't help but notice. The fly's metallic blue-green coloring stood in sharp contrast to the white spider.
One venomous bite to kill it. And soon the fly, Lucilia sericata, was toast. Milk toast.
Crab spiders don't build webs to trap their prey. They're cunning and agile hunters that spring into action when an unsuspecting prey appears on the scene. They belong to the family Thomisidae, which includes some 175 genera and more than 2100 species. And they're ancient: spiders date back 400 million years ago.
Do you like spiders? You should.
“Spiders are an incredibly diverse group with more than 50,000 species described with probably another 200,000 remaining to yet be discovered,” says spider expert Jason Bond, the Evert and Marion Schlinger Endowed Chair in Insect Systematics in the UC Davis Department of Entomology and Nematology.
It's worth repeating what Professor Bond said about spiders at the Bohart Museum of Entomology open house, “Eight-Legged Wonders,” on Saturday, March 9.
The five good reasons to like spiders:
- Spiders consume 400-800 million tons of prey, mostly insects, each year. Humans consume somewhere around 400 million tons of meat and fish each year.
- Spider silk is one of the strongest naturally occurring materials. Spider silk is stronger than steel, stronger and more stretchy than Kevlar; a pencil thick strand of spider silk could be used to stop a Boeing 747 in flight.
- Some spiders are incredibly fast – able to run up to 70 body lengths per second (10X faster than Usain Bolt).
- Athough nearly all 47,000-plus spider species have venom used to kill their insect prey, very few actually have venom that is harmful to humans.
- Some spiders are really good parents –wolf spider moms carry their young on their backs until they are ready to strike out on their own; female trapdoor spiders keep their broods safe inside their burrows often longer than one year, and some female jumping spiders even nurse their spiderlings with a protein rich substance comparable to milk.
Henrietta, our Stagmomantis limbata praying mantis, perches on a Mexican sunflower (Tithonia).
She is as patient as she is persistent.
The drone fly, aka syrphid and also known as a hover fly or flower fly, makes the fatal mistake of touching down on the same blossom.
Henrietta eyes it hungrily. Faster than a blink of the eye, she snares it, clutching it between her spiked forelegs.
"Well, of course, I like drone flies," she appears to be saying, between mouthfuls. "Thank you for asking."
Praying mantids are not known for their table manners. It's grab, hold and eat.
The cycle of life in the garden.
You're heard these idioms:
- The early bird gets the worm
- First come, first served.
- The second mouse gets the cheese.
But have you ever seen a Gulf Fritillary (Agraulis vanillae) eclose and then see her...well...engaged?
Such was the case on Labor Day, Sept. 3 in our little pollinator garden in Vacaville, Calif.
The female (we'll call her "Bride-to-Be") finishes eclosing and is hanging from her empty chrysalis, just drying her wings on the passionflower vine (aptly named) and getting acquainted with her new life stage and leafy surroundings.
Then, whoosh. A suitor (we'll call him "Groom-to-Be") appears out of nowhere. Well, from somewhere, but somewhere quite threatening. He looks tired and worn out, too fragile to fly. (As a colleague said: "He's accumulated a lot of frequent flier miles.") His ragged wings indicate a recent encounter with one or more predators, maybe a bird or a praying mantis. But he lucked out in the Predator-Prey tally: the final score, Butterfly, 1: Predator 0.
He lucks out again. He's the first to arrive at the altar. Our camera catches the action.
"In some Heliconius, the males locate female pupae and may even copulate with the female before she ecloses!" commented butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology. "They are related."
Labor Day, 2018.
The itsy bitsy spider climbed up the water spout.
Down came the rain and washed the spider out.
Out came the sun and dried up all the rain
and the itsy bitsy spider climbed up the spout again.
It was an itsy bitsy spider.
But it wasn't climbing up a water spout.
It was lurking, waiting for prey, on our Mexican sunflower.
This particular crab spider was quite visible--white on orange. Sometimes they're so camouflaged that you have to look twice to see them. We remember the perfectly camouflaged crab spider on a gold coin flower (Asteriscus maritimus). (See below).
Crab spiders belong to the family Thomisidae, which includes about 175 genera and more than 2100 species. Wikipedia tells us that "The common name crab spider is often applied to species in this family, but is also applied loosely to many other species of spiders. Among the Thomisidae, 'crab spider' refers most often to the familiar species of 'flower crab spiders,' though not all members of the family are limited to ambush hunting in flowers."
A partial solar eclipse is about to happen in Vacaville, Calif.
I am watching the insects: the honey bees nectaring on the African blue basil, an orbweaver spider munching on its prey, an assassin bug poised on a tropical milkweed, and a praying mantis lurking beneath a showy milkweed leaf.
Today (Aug. 21) is the long-awaited Great American Eclipse. The totality path will begin at 9 a.m. in Oregon, and stretch across the country to South Carolina.
Hmm, I wonder, how will the bugs in our pollinator garden react to a partial eclipse?
It won't be drastic, I predict. And it wasn't.
The partial eclipse in Vacaville began at 9:02 a.m. and reached its maximum (70 percent coverage of the sun) at 10:16. It ended at 11:38 am., a duration of two hours and 36 minutes.
The bees foraged before, during and after the eclipse, primarily on the African blue basil, which is usually covered with bees. During the height of the eclipse, however, as the skies darkened, a little more than half remained. After the eclipse, when the temperature increased and the wind ceased, the number of bees returned to normal.
"Honey bees tend to act like night is falling if the eclipse takes out quite a bit of the sunlight," says honey bee guru Eric Mussen, Extension apiculturist emeritus and president of the Western Apicultural Society. "Then they 'wake back up' afterwards."
Despite the eclipse, the spider kept eating its prey. (Sure hope it wasn't that blue dragonfly, Libellula luctuosa, "the widow skimmer" I saw yesterday.) The praying mantis kept lurking. The assassin bug raised its antennae. And the bees--although fewer of them--just kept foraging.
Two stink bugs opted to procreate on the bluebeard, Caryopteris x clandonensis. A Gulf Fritillary fluttered by and stopped to sip nectar from the Mexican sunflower (Tithonia). The assassin bug crawled higher on the milkweed, poised for an ambush.
The spider tugged its prey beneath a leaf, abandoning its web. Well, that's that, I thought.
Not so. The sticky web snagged a honey bee while the spider was polishing off its first prey. Okay, spider, you've already had your breakfast. You don't need a second helping. Not today."
I freed the struggling bee and off it buzzed to forage another day.
A partial eclipse, but a full escape...