- Author: Kathy Keatley Garvey
The warmth of the sun and the lure of nectar beckoned the hover flies or flower flies to our bee friendly garden.
We saw this one nectaring the rock purslane (Calandrinia grandiflora) last weekend. Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, identified it as "family Syrphidae, probably the genus Platycheirus."
It stood quite still, sipping the nectar and soon honey bees and a mason wasp joined it.
But for a minute, it seemed to have a "Mine" sign slapped on the blossom.
- Author: Kathy Keatley Garvey
Squatters' rights.
A dandelion poking through the rocks near Nick's Cove on Tomales Bay, in Marshall, Sonoma County, seemed an unlikely host for squatters' rights.
It first drew a tiny bee, barely a quarter-inch long. It was a female sweat bee, family Halictidae, genus Lasioglossum, subgenus Dialictus.
She claimed the dandelion all to herself.
Not for long.
Another insect shadowed the dandelion and swooped down to feed.
It was a hover fly, family Syrphidae. (Probably a Eristalinus aeneus, observed UC Davis pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis.)
So on one dandelion: a fly and a bee.
The fly is bigger. But the bee can sting. The sting, however, is rated only 1.0 on the Schmidt Sting Pain Index compiled by (now retired) entomologist Justin O. Schmidt at the Carl Hayden Bee Research Center, Tucson, Ariz.
Fight or flight?
Flight.
The dandelion blossom belongs to the fly.
- Author: Kathy Keatley Garvey
If it looks like a duck, quacks like a duck, and walks like a duck, it's probably a duck.
If it looks like a bee, buzzes like a bee, and visits flowers like a bee, it might not be a bee.
It could be a fly, or more specifically, a syrphid or flower fly.
Syrphids, also known as hover flies (from the family Syrphidae and order Diptera), are everywhere.
They hover over flowers like a helicopter over a meadow and then touch down. You'll see them nectaring blossoms, zipping from one flower to the other. When they're shadowed or startled, off they go.
Several of them were nectaring on our newly opened pink cactus blossoms this morning.
To the untrained eye, syrphids are often mistaken for honey bees. However, think number of wings (honey bees have four wings, syrphids have two), overall size, distinct coloration, and different antennae. Different antennae? Yes. Honey bees have long antennae bent at a right angle. Syrphids have a specialized bristle (arista) on the end of each antenna. It looks like a knob.
So, if it looks like a duck, walks like a duck and quacks like a duck, it's probably a duck.
If it visits flowers, it might not be a bee. It could "bee" a fly.
- Author: Kathy Keatley Garvey
Hover flies do know how to hover.
Like a helicopter with spinning blades, the hover fly lingers seemingly motionless in mid-air over a flower before zeroing down to feed on the nectar.
Sometimes they’re called flower flies. Sometimes syprhids. They’re from the family Syrphidae and mimic the black-and-yellow coloring of wasps or bees. The coloring protects them from predators. Leave me alone! Let me bee!
Last Sunday our rock purslane (Calandrinia grandiflora) attracted its share of honey bees and hover flies.
In fact, so popular was the rock purslane (which we purchased from Ray and Maria Lopez of El Rancho Nursery and Landscaping,
Instead I focused my macro lens, shot away, and then, for fun, altered the image in Photoshop with “poster edges.”
For a brief period, the hover fly became my poster child.
- Author: Kathy Keatley Garvey
To bee or not to bee.
Not to bee.
The flying insect hovering over the Ruth Risdon Storer Garden, UC Davis Arboretum, looked like a honey bee or wasp at first glance. It wasn't. It was a hover fly or syphrid fly from the order Diptera (Greek for "two wings") and family Syrphidae.
It's commonly known as a hover fly, drone fly, flower fly, syrphid fly or "syrphid," says Robbin Thorp, emeritus professor of entomology at UC Davis who researches native pollinators from his headquarters in the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road.
"These are good honey-bee mimics," he said, "but note the short stubby antennae and bulging face." Also note the large eyes! (Reminiscent of the eyes of the male honey bee, the drone).
The hover fly moves like a helicopter, holding perfectly still for a moment or two, and then darting upward, downward and backward in flight.
Unlike bees and wasps, syrphids have two wings, not four. Also a syrphid-notable: black and yellow stripes on their abdomen. The coloring helps fool would-be predators.
In their larval stages, syrphids dine on plant-sucking pests like tasty aphids, thrips, mealybugs and scales, or munch on decaying matter in the soil or in ponds and streams.
They're the good guys. And girls.
These beneficial insects are like the ladybird beetles (aka ladybugs) and lacewings of the garden. In their larval stages, they prey on pests, and in their adult stages, they pollinate flowers.
Prey 'n pollinate, that's what they do best.
And hover.