Posts Tagged: Robbin Thorp
Have you seen the little syrphid flies, aka flower flies and hover flies, hovering around the early spring blossoms?
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at the UC Davis Department of Entomology, said these syrphids (below) are probably from the genus Toxomerus. The family is Syrphidae (flower flies).
The larvae of these insects are good to have in your garden--they eat aphids, thrips and small caterpillars. The adults feed on nectar and pollen.
The syrphids fly so fast that you almost need a motor drive to capture them in flight. Plus, they seem especially skittish this time of year. Shadow them with your body or camera and they're gone in a flash.To learn more about flower flies, a good read is Robert Buggs' 25-page booklet, "Flower Flies (Syrphidae) and Other Biological Control Agents for Aphids in Vegetable Crops," published in May 2008 by the University of California, Division of Agriculture and Natural Resources (UC ANR). You can download it for free by accessing this page.
It's illustrated with photos that will help you recognize many of the syrphids.
The bumble bee population is declining and some species are teetering on the brink of extinction.
That's the gist behind why three conservation groups and bumble bee researcher Robbin Thorp, emeritus professor of entomology at UC Davis, are asking the federal government to impose regulations on the movement and health of commercial bumble bees to protect the declining native/wild bumble bee population.
A Jan. 12th press release issued by the Xerces Society for Invertebrate Conservation is drawing worldwide attention. The latest coverage came from the New York Times and the Washington Post.
Take Franklin's bumble bee. That's a bumble bee found only in a small stretch of southern Oregon and northern California. Robbin Thorp, a member of the Xerces Society, hasn't seen it for several years and fears it may be extinct.
You'll want to read the article on "Bumble Bees in Decline" on the Xerces Society Web site and look at the photos of the bumble bees that could be nearing extinction.
Two recent studies provide a direct link between diseases in commercial bumble bees and the health of wild bumble bees:
--Otterstatter, M.C., and J.D. Thomson. 2008. Does Pathogen Spillover from Commercially Reared Bumble Bees Threaten Wild Pollinators? PLoS One. Available online at http://www.plosone.org/doi/pone.0002771
--Colla, S.R., M.C. Otterstatter, R.J. Gegear, and J.D. Thomson. 2006. Plight of the Bumblebee: Pathogen Spillover from Commercial to Wild Populations. Biological Conservation 129: 461-467.
Otterstatter and Thomson note that wild bumble bees near greenhouses have higher pathogen loads (of Crithidia bombi and Nosema bombi) than bumble bees farther away from greenhouses.We're glad to see this kind of research under way and the proposed restrictions sent to the USDA. We need to protect our wild bumble bees.
Franklin's Bumble Bee
The January newsletter published by the eXtension.org Bee Health Community of Practice includes:
* New Feature: Managed Pollinator CAP Updates
* Social Media Strategy Developed
* YouTube Channel Launched
* New Feature: University of Florida Bee Disease Videos
* FAQ's Organized by Category
* Google Analytics: Bee Health Homepage in Top 10 at eXtension.org
* On the Calender
One of the many bee experts who answers the Frequently Asked Questions (FAQs) is John Skinner of the University of Tennessee, who has strong UC Davis connections. He received his doctorate in entomology from UC Davis in 1987, studying with major professor and native pollinator specialist Robbin Thorp. Although an emeritus professor since 1994, Thorp continues his research. He maintains an office in the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis.
Here's a sampling of the questions that Skinner answered in the last few months:
How Do Bees Make Wax?
Bees produce the beeswax used in the construction of their combs from the four pair of wax glands located on the underside of the abdomen. These glands are most highly developed and active in bees 10-18 days old. The wax appears in small, irregular oval flakes or scales that project between the overlapped portions of the last four abdominal segments. Wax can be secreted only at relatively high temperatures and after a large intake of honey or nectar. --John Skinner, University of TennesseeHow Do Bees in a Swarm Determine Where to Go for a New Home?
A swarm of bees hanging on a branch includes a queen and thousands of worker bees. Some of these bees function as scouts and search the surrounding area for a suitable category to move into. The scouts return to the swarm cluster and dance to communicate information to the bees in the swarm. There may be numerous dances all going on at the same time. The results are similar to a dance contest where the number of dances is reduced until only one dancer left. Within a half hour of reaching an “agreement” the swarm flies to the new location. --John Skinner, University of TennesseeHow Long Do Honey Bees Live?
During the active season, the lifetime of a worker is five to six weeks. Overwintering worker bees may, however, live for four to six months. Whatever their life span, worker bees usually confine themselves to one task at a time, working without pause. If they are field bees, they may be scouts or collectors. Scouts look for sources of nectar and pollen. Once suitable sources are located, the scouts recruit additional foragers.
Nectar collectors, pollen foragers, water gatherers or propolis gatherers work so single-mindedly at their jobs, they will not stop even to collect honey placed before them. During the day, one may see hundreds of spent workers, wings ragged, returning wearily to the hive. Worker bees are aptly named as they literally work themselves to death. Death occurs following approximately 500 miles of flight. --John Skinner, University of TennesseeHow Can Worker Honey Bees Perform So Many Tasks in Their Short Lives?
The lives of the worker bees fall roughly into two periods. During the first period of approximately three weeks, they are called hive or house bees. On emerging from their cells, they groom themselves and engorge on honey and pollen from the storage cells. Their first three days are spent cleaning out brood cells. Thereafter as they mature, glands including labial, salivary, hypopharangeal and wax become functional they feed the older larvae and then the younger larvae, take orientation flights, evaporate nectar, build comb, feed the queen and the drones, keep an even temperature in the brood nest and guard the entrance to the hive. These differences in responsibilities based on worker age are known as a division of labor. But, depending on specific circumstances, it can be very flexible.
The last half of a worker bee’s adult life is devoted to foraging duties outside the hive. Four necessary items collected outside the hive are pollen, nectar, water and propolis (bee glue).--John Skinner, University of TennesseeGot a question? Just ask it on this page.
Another noted bee expert connected with the "Bee Health" Web site is Extension Apiculturist Eric Mussen, member of the UC Davis Department of Entomology faculty. Read some of his answers to FAQs posted on the Harry H. Laidlaw Jr. Honey Bee Research Facility Web site.
It's all about keeping our bees healthy.
Trio on Sedum
What a treasure!
Have you seen the Xerces Society's new online Pollinator Conservation Resource Center?
This is something that's long been needed. It's a wealth of information--that's why it's a treasure.
As Matthew Shepherd of the Xerces Society for Invertebrate Conservation says: "...the resource center gives access to all you need to complete a pollinator conservation project in any region of the United States. When you visit the resource center, select your region from the map to access plant lists, details of creating and managing nest sites, pesticide protection guides, and practical guidance on planning and implementing habitat projects on farmlands, gardens, golf courses, parks, and wildlands."
"We want the resource center to be the most comprehensive source of pollinator conservation information currently online and will update it as often as we can, adding new materials as they become available."
Shepherd says the resource center is "the result of a collaboration with Neal Williams of the University of California, Davis. In particular, we thank Katharina Ullmann, previously with the Xerces Society and now a member of Neal Williams' research group, for gathering many of the resources."
Among the others lending their expertise: native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis who maintains an office in the Harry H. Laidlaw Jr. Honey Bee Research Facility.
How easy is it to use this site?
Say, for example, you want to plant a bee friendly garden. All you do is click on a link and you'll know what to plant seasonally in your area and what each plant will attract. Then you can click on the various pollinators to see what they look like.
If this Web site were gold, it would be in Fort Knox.
Female sweat bee
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.
Hover fly on rock purslane
Ready for Take-Off