- Author: Kathy Keatley Garvey
You could call it a slacker, a deadbeat, a moocher, a sponger, or a loafer.
Or you could call it a cuckoo bee.
Take the cuckoo bee, Xeromelecta californica, a parasite of the digger bee, Anthophora.
When the female Anthophora leaves its nest to collect more pollen, the female cuckoo bee sneaks in and lays an egg.
"When the host female seals her nest, it seals the doom of her own offspring," distinguished emeritus professor Robbin Thorp of the UC Davis Department of Entomology and Nematology told the crowd at last week's 40th annual Western Apicultural Society meeting, held at UC Davis. They eat the provisions, a pollen ball meant for the host offspring, and kill and eat the host larvae.
The cuckoo bee offspring emerge.
Thorp, co-author of California Bees and Blooms: A Guide for Gardeners and Naturalists, also called attention to their "pointy abdomen" and "wasp-looking appearance."
But they are bees--cuckoo bees. They're also called parasitic bees or "kleptoparasites" or "cleptoparasitises."
They have no pollen-carrying/collecting apparatus, like a scopa, because they don't need any, Thorp said, just as they do not construct their own nests.
If you look around a pollinator garden, you just might sight some cuckoo bees. Last week we saw a Xeromelecta californica (as identified by Thorp and Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis professor of entomology). It was sipping nectar from a tropical milkweed, Asclepias curassavica.
We've also spotted Anthophora urbana nectaring on our lavender.
One thing's for certain: a cuckoo bee didn't lay its eggs in the Anthophora nest that time or the urbana wouldn't have been there.
- Author: Kathy Keatley Garvey
A fly, oh, my!
On the approval scale, they don't rank nearly as high as honey bees, but some are often mistaken for them.
Take the Eristalis stipator, which belongs to the family Syrphidae, the hover flies.
It's about the same size as a honey bee and it's a pollinator.
We recently spotted this one--a female Eristalis stipator, as identified by senior insect biosystematist Martin Hauser of the California Department of Food and Agriculture--nectaring on tropical milkweed, Asclepias curassavica. The colors are striking--both the colors of the fly and the flowers. It's a striped fly, with black and white bands, one superimposed gold band, and buff-colored hairs piled on the thorax. And the showy flower, aka "blood flower," is red-orange with a yellow hood.
Eristalis is a large genus of approximately 99 species. The Eristalis stipator has no common name, so we just call it Eristalis stipator.
Or a fly.
- Author: Kathy Keatley Garvey
A little haggard, a little worn, a little ragged, a little torn.
But there she was on Monday, Aug. 1, the first monarch of the season to lay eggs in our little pollinator garden in Vacaville, Calif.
She found the milkweed, but that was AFTER the aphids, milkweed bugs, praying mantids, assassin bugs and assorted spiders claimed it.
It's always a joy to see the majestic monarch fluttering through a pollinator garden. On Sunday, July 31, a male lingered for two hours, nectaring on the Mexican sunflower (Tithonia) as the male territorial longhorn bees tried to chase him away. No welcome mat for him! No place setting for him!
Then today, a female arrived, first stopping by the showy milkweed, Asclepias speciosa, to lay eggs and then fluttering over to the tropical milkweed, Asclepias curassavica, to lay more.
It's amazing how the monarchs, Danaus plexippus, know how to put their "resources" in multiple places. Like the idiom that cautions "don't put all your eggs in one basket," instinctively they seem to know that if they put all their resources in one place, they could lose them all. There's a better chance of offspring survival if they spread the eggs around.
We'll see.
- Author: Kathy Keatley Garvey
All summer and into fall, we spotted the familiar reddish, black and white bugs scurrying around on our showy milkweed, Asclepias speciosa, and tropical milkweed, Asclepias curassavica.
Showy bugs on showy milkweed.
The ones we saw: the Small Milkweed Bug, Lygaeus kalmii. Like its name implies, it's small, about half an inch long.
They're primarily seed eaters, but they're opportunistic and generalists, says insect migration biologist Hugh Dingle, emeritus professor of the UC Davis Department of Entomology and Nematology, author of the popular textbook, Animal Migration: the Biology of Life on the Move. "They'll get protein from wherever they can find it," he said. Dingle, whose research includes migratory monarchs, said the milkweed bugs not only eat seeds, but they also eat monarch eggs and larvae and the immature stages of other butterflies. Forever the opportunists, they eat other small bugs as well--if the opportunity arises. And they feed on nectar, too.
Some scientists have seen them feeding on insects trapped in the sticky pollen of the showy milkweed.
The bugs, it seem, have few predators. They feed on the toxic milkweed, which makes them distasteful to predators, prey to avoid. Their warning colors (red and black) strike home that fact.
In the fall, as the seed pods burst open, it's a horticulture/culinary war between the milkweed growers and the milkweed bugs. Both want the seeds: the humans to plant them and the bugs to eat them.
(Note: Research shows that the milkweed bug also feeds on other plants. Read about the opportunist Small Milkweed Bug in the Journal of the New York Entomological Society.)
- Author: Kathy Keatley Garvey
So here it is Monday, Oct. 10 and the monarch butterflies are still laying eggs on our milkweed in Vacaville, Calif.
"Mrs. October" fluttered down to our tropical milkweed at 4:30 p.m. today and began laying eggs on three tropical milkweeds (Asclepias curassavica).
We grow three other species--showy milkweed, Asclepias speciosa; narrow-leafed milkweed, Asclepias fascicularis; and butterfly milkweed, Asclepias tuberosa. All are looking quite healthy, but Mrs. October chose the tropical milkweed.
As she tended to her maternal business, several migrating monarchs glided down to sip some nectar (flight fuel) from Mexican sunflower (Tithonia) and butterfly bush (Buddleja davidii) in our pollinator garden. Other monarchs seemed interested in finding partners. In October? Apparently so. Temperatures have hovered around 90 degrees for the last several days.
And here I was just telling the family, "My monarch-rearing season is almost over. I have two chrysalids left (in our indoor habitat). If monarchs eclose, that will make a total of 50 monarchs reared and released this season." (This is my small-scale conservation project to help the declining monarch population.)
Not so fast. We now have four monarch eggs, four eggs rescued from assorted predators (lady beetles, milkweed bugs, spiders, ants, and other critters looking for a tasty bit of protein. Pathogens, tachinid flies, wasps, assassin bugs and birds also "interrupt" the natural life cycle of a monarch. (See enemies of monarchs from monarchprogram.org.)
With any luck, the monarch eggs will become caterpillars, then chrysalids and then adults, thanks to Mrs. October's unexpected gift.
However, it's not good to count your chickens before they hatch...or the monarchs before they eclose.
