The Girl and the Bubble

Aug 20, 2012

The Girl and the Bubble

Aug 20, 2012

Ah, the little intricacies of life...

We were walking along a stretch of the coastal town of Bodega Bay when we spotted something we'd never seen before: a bubble on a syrphid fly.

Syrphid flies, also known as hover flies or flower flies, are pollinators, just like honey bees. As floral visitors, syrphids are often mistaken for bees. They're not. They're flies.

But what was the bubble?

Several of our UC Davis entomologists weighed in.

"Weird, I wonder if that's an egg," said one entomologist. "Looks like the ovipositor is extended."

Said another: "If this were a honey bee, I would suggest that you shot your first defecation photo." (Spoken like the true honey bee expert he is!)

And another: "My guess is that droplet is fly (note: brace yourself--here comes the "p" word) poop, composed mostly of digested pollen grains that the flies commonly feed on. If you look closely at the abdomen of these flies, you often see the gut outlined with yellow or orange through the semi-translucent membrane areas of the abdomen due to the pollen they have ingested."

We asked fly expert and  senior insect biosystematist Martin Hauser of the California Department of Food and Agriculture's Plant Pest Diagnostic Branch for an I.D. of this syrphid fly. "A female Sphaerophoria," he said.

And, oh, yes, the bubble is not an egg. It's the "p double oh p" word with pollen inside. Hauser pointed out that the eggs are oval and white, so the yellow bubble is not an egg. Check out this photo of syrphid eggs on the bugguide.net website, Hauser said. And here's a image on bugguidenet.com of the syrphid fly ovipositing.

Mystery solved!

Sounds like a good question for an Entomology 101 quiz...

Or the Linnaean Games...