Posts Tagged: Robbin Thorp
Billed as "the first comprehensive guide to North American bumble bees to be published in more than a century," it allows readers, both amateurs and professionals, to identify all 46 bumble bee species found in North America and learn about their ecology, changing geographic distributions, and the endangered and threatened species.
Bumble bees, you know, are among the most recognizable of the world's 20,000 species of bees. The genus, Bombus, has only 250 species. A small number, indeed.
A yellow-faced bumble bee, Bombus vosnesenskii, on tower of jewels. (Photo by Kathy Keatley Garvey)
A honey bee and yellow-faced bumble bee sharing a coneflower. (Photo by Kathy Keatley Garvey)
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis. (Photo by Kathy Keatley Garvey)
Incredible. Absolutely incredible.
The Western bumble bee (Bombus occidentalis) seems to be making a comeback of sorts in some parts of the West.
Reporter Michelle Nijhuis, in an Oct. 14th article in High Country News, wrote that this species was "once among the most common bumble bees in the Western United States (and Western Canada)." The population crashed in the 1990s and "all but disappeared from about a quarter of its historic range." Now, she says, it's recently been spotted in parts of Washington and Oregon.
Someone saw six species of the Western bumble bee pollinating blackberries just north of a Seattle.
That's good news indeed.
We remember last year when native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, was searching for the critically imperiled Franklin's bumble bee in its tiny range in northern California and southern Oregon, when a sole Western bumble bee appeared in front of him and his colleagues from the U.S. Forest Service. It was foraging on buckwheat (Eriogonum sp.) on Mt. Shasta, above 5000 feet.
Thorp and many other scientists fear that the Western bumble bee may go the way of Franklin's bumble bee.
That's why Thorp describes the Seattle find as "very exciting."
"Any finds west of the Sierra-Cascade crest are of prime interest. It is those western populations that took the sharp dive between 1999-2002. They do seem to be increasing, which is indeed encouraging."
"Many populations east of the crest seem to have persisted, through this decline," Thorp noted, "but were not carefully monitored during this time so we don't have the detailed data on their population trends that we would like."
Bombus occidentalis is sometimes called the "white-bottomed bee" due to its distinctive white markings on its abdomen. It is known for pollinating blackberries, cherries, apples and blueberries. It also is "an excellent pollinator of greenhouse tomatoes and cranberries, and has been commercially reared to pollinate these crops," according to the Xerces Society for Invertebrate Conservation website.
Read about the decline of bumble bees on the Xerces website.
And if you live in the West, keep your eyes open for the Western bumble bee.
This Western bumble bee was found on Mt. Shasta on Aug. 15, 2012. (Photo by Kathy Keatley Garvey)
Close-up of Western bumble bee. (Photo by Kathy Keatley Garvey)
A brilliant sunflower clinging to the red ring of autumn.
And here comes a common sunflower bee, Melissodes agilis (this is a female, as identified by native pollinator specialist Robbin Thorp, emeritus professor of entomology at the University of California, Davis.)
The sunflower bee is a specialist on sunflowers (Helianthus spp.). Scientists know this as a long-horned ground-nesting bee, a member of Anthophoridae. Both the plant and the bee are native to the United States.
Melissodes agilis is commercially important. And it's common.
But there's nothing "common" about it when "sunflower bee" meets "sunflower."
The beauty is overwhelming.
Sunflower bee, Melissodes agilis, on sunflower. (Photo by Kathy Keatley Garvey)
Hi, nice to meet you! (Photo by Kathy Keatley Garvey)
Time to leave! (Photo by Kathy Keatley Garvey)
Valley carpenter bees are passionate about passionflower vines (Passiflora).
You see these black bees foraging on the blossoms. Tiny grains of golden pollen, looking like gold dust, dot the thorax.
Their loud buzz frightens many a person, but wait, they're pollinators.
Valley carpenter bees (Xylocopa varipuncta) are found in the Central Valley and southern California, Arizona, New Mexico and southward through Mexico, according to native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis.
These carpenter bees are large (about the size of a queen bumble bee). The females are solid black, while the males are golden/buff-colored with green eyes.
We receive scores of calls about "golden bumble bees." They're the male Valley carpenter bees, sometimes nicknamed "Teddy bears."
The females are the only ones we've seen in the passionflower vines, though.
The males? They must be cruising somewhere else, patrolling for females.
Most of the time we see female Gulf Fritillary butterflies (Agraulis vanillae) laying their eggs on the leaves, and male Gulf Frits searching for females.
A female Valley carpenter bee is covered with yellow pollen. (Photo by Kathy Keatley Garvey)
Female Valley carpenter bee on a passionflower blossom. (Photo by Kathy Keatley Garvey)
The world's "100 Most Endangered Species" are back in the news again, and well they should be.
Back in 2012, The International Union for Conservation of Nature (IUCN) and the Zoological Society of London released a list of the 100 Most Threatened Species when the IUCN World Conservation Congress met in South Korea.
That means more attention to Franklin's bumble bee (Bombus franklinii), a critically imperiled bumble bee that UC Davis native pollinator specialist Robbin Thorp has monitored since 1998.
Thorp, emeritus professor of entomology, says the distinctively marked bumble bee has the most restricted range of any bumble bee in the world. Its habitat is--or was--a small area of southern Oregon (Douglas, Jackson and Josephine counties) and northern California (Siskiyou and Trinity counties).
Franklin’s bumble bee frequents California poppies, lupines, vetch, wild roses, blackberries, clover, sweet peas, horsemint and mountain penny royal during its flight season, from mid-May through September. It collects pollen primarily from lupines and poppies and gathers nectar mainly from mints.
Thorp and the Xerces Society for Invertebrate Conservation are the forces behind the Franklin's bumble bee campaign to find it and protect it. See the Xerces website for more information about the bee.
Thorp sighted 94 in 1998; 20 in 1999; 9 in 2000 and only 1 in 2001. Sightings increased slightly to 20 in 2002, but dropped to 3 in 2003. Thorp saw none in 2004 and 2005; one in 2006; and none since. Now scores of people from all walks of life are looking for it, but no one has found it.
Franklin's bumble bee is one of several insects on the worldwide list. The other species include several butterflies, Actinote zikani, Parides burchellanus and Pomarea whitneyi; the Seychelles Earwig (Antisolabis seychellensis); Beydaglari Bush-cricket (Psorodonotus ebneri); and a damsel fly (Risiocnemis seidenschwarzi).
Or Franklin's bumble bee.
Robbin Thorp with his computer screen showing a photo he took of Franklin's bumble bee, one of the world's 100 most endangered species. (Photo by Kathy Keatley Garvey)
This macro image of Franklin's bumble bee is the work of Robbin Thorp.