When was the last time you sighted a bumble bee? Photographed it?
It's National Pollinator Week and one of our favorite bumble bees is the yellow-faced bumble bee, Bombus vosnesenskii. It was also a favorite of internationally renowned bee expert Robbin Thorp, distinguished emeritus professor of entomology at the University of California, Davis, who passed away June 7 at age 85. (See obituary)
In fact, all bumble bees were his favorite, including the elusive Franklin's bumble bee, found only in a small range in southern Oregon and northern California and now feared extinct. We remember a July 2010 interview with Thorp:
“People often ask the value of Franklin's bumble bee," Thorp told us. "In terms of a direct contribution to the grand scale of human economies, perhaps not much, but no one has measured its contribution in those terms. However, in the grand scheme of our planet and its environmental values, I would say it is priceless.”
“Loss of a species, especially a pollinator, diminishes our global environment,” he said. “Bumble bees provide an important ecological service--pollination. This service is critical to reproduction of a huge diversity of plants that in turn provide shelter, food (seeds, fruits) to diverse wildlife. The potential cascade of effects from the removal of even one localized pollinator may affect us directly and indirectly.”
Thorp treasured bumble bees and encouraged everyone else to do so, too.
The yellow-faced bumble bees are native to the west coast of North America, from Baja California to British Columbia. They're important pollinators, especially important for their buzz pollination of tomatoes, peppers and cranberries. Buzz pollination occurs when they grab a blossom and shake it, dislodging the pollen. Honey bees can't do that.
The Xerces Society for Invertebrate Conservation recently posted that one quarter (28 percent) of North American bumble bees are in some degree of extinction risk. "Bumble bees face many threats including habitat loss, disease, pesticide use, and climate change." (See more information on bumble bees on the Xerces' site.)
Meanwhile, "across the pond," London has established a seven-mile long bee corridor of wildflowers just for pollinators.
"The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) said wild mammals had declined by 82 per cent since 1980, space for natural ecosystems had halved, and one million species were now at risk of extinction as a result of human action," according to a May 7, 2019 article in The Independent newspaper. "Insect pollinators are vital for the maintenance of ecosystem health and for global food security. Insects are required to maintain the existence of 75 per cent of crop species, 35 per cent of global crop production and up to 88 per cent of flowering plant species," reporter Harry Cockburn wrote.
Want to learn more about the bumble bees around us? A good start is to read these two books, both co-authored by Thorp in his retirement: Bumble Bees of North America: An Identification Guide (Princeton University, 2014) and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday, 2014).
And, if you would like to get involved in citizen science, Bumble Bee Watch seeks your sightings.
The boys are back in town.
After the long winter and rainy spring, the boys are back in town.
That would be the male Valley carpenter bees, Xylocopa varipuncta, or what Robbin Thorp, distinguished emeritus professor of entomology at UC Davis, calls "the teddy bear bees."
They're fuzzy green-eyed blonds, while the female of the species is a solid black, a good example of sexual dimorphism.
You've heard folks say of dogs: "Their bark is worse than their bite?" Well, these bees can't sting ("boy bees don't sting"), but they're good bluffers as they buzz around you. They're also good pollinators.
We saw this one nectaring on our tower of jewels, Echium wildpretii. He lingered among the honey bees and syrphid flies, and then buzzed off.
He will return.
Seeking more information about California's bees? Read the landmark book, California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday Press), the work of UC-affiliated authors Gordon Frankie, Robbin Thorp, Rollin E. Coville, and Barbara Ertte. The book is available online and at numerous other sites. At UC Davis, you can find it at the Bohart Museum of Entomology, 1124 Academic Surge Building on Crocker Lane (and with other bee books at UC Davis Stores)./span>
Let's hear it for the tower of jewels, Echium wildpretii.
Native to the island of Tenerife and belonging to the family Boraginaceae, it can tower as high as a 10-foot Christmas tree. It's a biennial, meaning that it takes two growing seasons to complete its life cycle. It won't bloom until the second year, but it's worth the wait. The red flowers are nothing but spectacular. Then it dies. But if you're lucky, you'll be able to reap some seeds.
What's better than a tower of jewels? A tower of bees. Bees love it for the high nectar content.
Grab a camera, preferably in the late afternoon, and follow the bees.
The Echium wildpretii is commonly known as "The Tower of Jewels" but it ought to be known as "The Tower of Beauty."
That's especially when honey bees gather to collect the blue pollen and sip the sweet nectar.
Or when their wings glisten in the early morning sun.
Or when it's National Pollinator Week.
In our family, we call it "The Christmas Tree" due to two reasons: its height (it's as tall as a Christmas tree) and due to its spiked red blossoms, the color of Christmas.
The plant, in the family Boraginaceae, is biennial and it can reach 10 feet in height. You often see its purple-spiked cousin, the Pride of Madeira (Echium candicans) growing wild in Sonoma, along the roads to Bodega Bay.
The species is endemic to the island of Tenerife. There they call it "Tenerife bugloss."
Whatever you call the plant, it's good to see it racing up the popularity scale as gardeners seek it for their pollinator gardens. There's even a Facebook page, "We got an Echium through the winter."
Common question: "Anyone got seeds for sale?'
Echium wildpretii is that pretty.
If any insect should be the "cover girl" during National Pollinator Week, it ought to be the honey bee (Apis mellifera)
Specifically, it should be the worker bee, although the queen bee and drones (males) have their place, too.
But it's the worker bee, the forager, that basically works herself to death. She's out gathering nectar, pollen, propolis and water for her colony. She never calls in sick. She never punches a time card. She never protests. As soon as the temperature hits around 55 degrees, she leaves the warmth of the hive to go to work.
She might not return. She may run into pesticides, pests or predators (think spiders, praying mantids, wasps, birds and the like). She may wind up spending the night on a lavender blossom when it's too cold or too dark to return to the hive. She may have to fly five miles on ragged wings and in ragged weather carrying a load heavier than she is.
Once inside, she shares her bounty with the colony. She dances to let her sisters know where she found it. This isn't America's Got Talent--these dances are not for money or fame, but for purpose. "Hey, I just found a large quantity of lavender about two miles away. It's great quality. Let's go get more."
Her weapon is her stinger, but she uses that only in defense of the hive, or when something crushes her (like a human being that accidentally steps on her). She can't be compared to an assault weapon such as an AR-15 that can shoot 25 rounds in 2.5 seconds. One sting and she dies. One barbed sting and it's all over for her.
And she's beautiful, whether she's golden, light brown or gray-black.
The Journal of Economic Entomology, published by the Entomological Society of America, graced its June cover with a honey bee. It's of a forager heading toward a tower of jewels (Echium wildpretii). The background: I captured the image several years ago in my pollinator garden in Vacaville, as I watched, awestruck, as the worker bees turned the tower of jewels into a buzzing tower of bees. Oh, sure, bumble bees, carpenter bees, leafcutter bees, sweat bees, syrphids, butterflies and hummingbirds were working the blossoms, too, but it was this determined worker bee that caught my eye.
She probably died several weeks after that flight photo. Honey bees live only four to six weeks during the busy season. The queen bee, an egg-laying machine that can pump out 2000 eggs a day, quickly replaced her.
For a moment, though, as the bee headed for the tower of jewels, time stopped. The worker bee did not.
Happy National Pollinator Week!