- Author: Kathy Keatley Garvey
Wild bee diversity is declining worldwide at unprecedented rates, and steps must be taken to conserve them--and not just those that are the main pollinators of agricultural crops, agreed 58 bee researchers in a study published today (June 16) in Nature Communications, an open-access journal based in London.
"This study provides important support for the role of wild bees to crop pollination through a comprehensive global summary,” said co-author and pollination ecologist Neal Williams, associate professor in the UC Davis Department of Entomology and Nematology. “At the same time, we found that in any one region, much of the pollination services from wild bees to a given crop come from just a few species, thus we need to be careful about using a simplistic economic ecosystem-services argument for biodiversity conservation and maintain actions that target biodiversity as specific goal. "
Wild bees, or non-managed bees, include bumble bees (genus Bombus), sweat bees (genus Lasioglossum) and small carpenter bees (genus Ceratina).
The study, led by David Kleijn of Wageningen University, The Netherlands, found that of the almost 80 percent of crop pollination provided solely by wild bees, only 2 percent are by the most common species. This indicates that the benefits of conserving only economically important organisms are not the same as the benefits of conserving a broad diversity of species, the researchers said.
The paper, “Delivery of Crop Pollination Services is an Insufficient Argument for Wild Pollinator Conservation,” is online at http://www.nature.com/naturecommunications. Among the co-authors are native pollinator specialist Robbin Thorp, distinguished emeritus professor of entomology at UC Davis, and conservation biologist Claire Kremen of UC Berkeley, a longtime associate of the UC Davis Department of Entomology and Nematology.
“My role in this paper was through my collaborations with Neal Williams and Claire Kremen in their research projects on crop pollination by native bees,” Thorp said. “My identifications of the bees they sampled, provided the raw data for the calculations performed on the diversity and abundances of the bees pollinating the crops they studied.”
“There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation,” the researchers wrote in their abstract. “However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops.”
“Dominant crop pollinators,” they pointed out, “persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost-effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments.”
The researchers analyzed data from more than 90 studies on five continents, including Europe and North America. They concluded that the higher levels of biodiversity provide greater benefits to the functioning and stability of ecosystems, with some functions also being “economically beneficial” for humans.
Kleijn and his colleagues studied 785 species, analyzing which provide the best economic returns from crop pollination. They found that wild bee communities contribute an average of more than $3,251 per hectare (2.471 acres) to the production of crops, and that they provide the same economic contributions as managed honey bee colonies. However, they also noted that the majority of crop pollination services provided by wild bees are accomplished by only a small subset of the most common species.
“Across the 90 studies, we collected a total of 73,649 individual bees of 785 species visiting crop flowers,” the authors wrote. “Although is an impressive number, it represents only 12.6 percent of the currently known number of species occurring in the states or countries where our studies took place. When we consider only bee species that contribute 5 percent or more to the relative visitation rate of any single study, the percentage drops to 3 percent of the species in the regional species pool. Yet these 2 percent of species account for almost 80 percent of all crop visits.”
These results suggest that conservation efforts targeted directly at a few species providing the majority of ecosystem services, such as crop pollination, would represent a good strategy if the goal is to improve economic returns. However, they said such a strategy is unlikely to be compatible with conserving threatened species and biological diversity “if the goal is to improve the functioning and stability of ecosystems.”
Williams worked with Kleijn and Winfree of Rutgers University New Brunswick, N.J., to conceive of some of the approaches used, particularly suggested looking at the abundance distributions of crop bees within the larger species pools of the region to understand whether the most important crop pollinators species are simply the common bees overall.
Williams and Kremen also contributed to the manuscript, from the early drafts to the final versions.
- Author: Kathy Keatley Garvey
The two emeriti professors from the UC Davis Department of Entomology and Nematology were among five honored at the event. Also honored were Dickson recipients/emeriti professor Daniel Anderson of the Department of Land, Air and Water Resources; Martha Macri of the Department of Linguistics; and Peter Schiffman, Department of Geology. (See web page.)
UC Davis Chancellor Linda P. B. Katehi, Provost Executive Vice Chancellor Ralph Hexter, and emcee Bill Rains, past president of the UC Davis Emeriti Association, praised them for their work.
Robbin Thorp
Thorp was singled out for the distinguished emeritus award for his outstanding scholarly work and service accomplished since his retirement in 1994. "Dr. Robbin Thorp should be the first scientist to be cloned," said emcee Rains, quoting James Cane of the USDA-ARS Pollinating Insect Research Unit, Utah State University, Logan.
Thorp, who joined the UC Davis entomology faculty in 1964 and achieved emeritus status in 1994, is a state, national and global authority on pollination ecology, ecology and systematics of honey bees, bumble bees, vernal pool bees, conservation of bees, contribution of native bees to crop pollination, and bees of urban gardens and agricultural landscapes.
Since his retirement, he has compiled an exemplary record for his research, teaching, publications, presentations, and advisement services, sharing his expertise with local, statewide, national and international audiences. In his retirement, he has published 68 papers and is the first author on 15 publications. He received several prestigious awards: the 2013 outstanding team award, with several colleagues, from the Pacific Branch of the Entomological Society of America, and the 2010-2011 Edward A. Dickson Emeriti Professorship, UC Davis. Thorp is the North American regional co-chair for the International Union for Conservation of Nature (IUCN) Bumblebee Specialist group. He is a member of 10 professional societies, including the International Society of Hymenopterists.
Thorp maintains his office and research headquarters in the Harry H. Laidlaw Jr. Honey Bee Research Facility on the UC Davis campus. Among his latest publications: he co-authored two books published in 2014: Bumble Bees of North America: An Identification Guide (Princeton University Press) and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday). Of the 20,000 bee species identified worldwide, some 4000 are found in the United States, and 1600 in California.
Thorp spends much of his time in the Bohart Museum of Entomology, which houses collections critical to his bee identification work. He identifies species and regularly volunteers at the open houses and other event.
Thorp is an integral part of The Bee Course, an annual 10-day workshop sponsored by the American Museum of Natural History and held at the Southwestern Field Station near Portal, Ariz. He has taught there since 2002 (the instructors are all volunteers), and even though he is 81 years young, he plans to continue teaching there. (See more on the departmental web page.)
Hugh Dingle
Hugh Dingle. an international authority on animal migration, received a Dickson award to help fund his research on monarch butterflies, “Monarchs in the Pacific: Is Contemporary Evolution Occurring on Isolated Islands?” Monarch butterflies established just 200 years ago in remote Pacific islands are undergoing contemporary evolution through differences in their wing span and other changes, he believes.
Dingle, author of two editions of “Migration: The Biology of Life on the Move,” said his previous studies reveal that migrant and resident monarchs exhibit different wing shapes. He will be working with community ecologist Louie Yang and molecular geneticist Joanna Chiu, assistant professors in the UC Davis Department of Entomology and Nematology, to examine the ecology and physiology of monarch butterflies (Danaus plexippus) in three islands where contemporary evolution might be expected. The islands are Oahu (Hawaii), Guam (Marianas) and Weno (Chuuk or Truk).
“This is the necessary first step in a long-term analysis of the evolutionary ecology and physiology of monarch butterflies on remote Pacific islands,” said Dingle, a fellow of the American Association for the Advancement of Science and the Animal Behavior Society.
Dingle said the monarch, widely distributed “for eons” in the New World, is fairly new to the Pacific islands and to Australia. “In addition to North America, the monarch occurs as a resident throughout the Caribbean and Central and northern South America—and probably as a migrant farther south. One of the more intriguing aspects of its distribution is that beginning in the early part of the 19th century, it spread throughout the Pacific all the way to Australia, where there are now well-established migratory and non-migratory populations.”
Dingle speculates that the monarchs arrived in the Pacific islands with their host plant, milkweed, which was valued at the time for its medicinal properties. Some of the islands are extremely isolated, he said.
An analysis of a monarch population in Hawaii shows that resident monarchs have shorter, broader wings than the long-distance migrants. The Hawaii butterfly wings were shorter than the eastern U.S. long-distance migrants, but “not so short-winged as the residents in the Caribbean or Costa Rica, which have been present in those locations for eons, rather than the 200 years for Hawaii.”
“If there are indeed wing shape changes associated with evolution in isolation, are there other changes that may have occurred under selection and local adaptation for residency?” Dingle wonders. “Are there other changes that may have occurred under selection and local adaptation for residency? Examples of such traits might be changes in flight muscle physiology, changes in photoperiodic diapause response, changes in the characteristics of orientation ability and its relation to antennal circadian rhythms, or changes in the reproductive capacity or tactics (re-colonization of ‘empty' habitats is no longer part of the life cycle).
Dingle published the second edition of “Migration: The Biology of Life on the Move” (Oxford University Press) in November 2014. It is the sequel to the widely acclaimed first edition, published in 1996. National Geographic featured Dingle in its cover story on “Great Migrations” in November 2010. LiveScience interviewed him for its November 2010 piece on “Why Do Animals Migrate?” (See more on the departmental web page.)
Emeriti Luncheon
Preceding the ceremony, Chancellor Katehi presented a progress report on UC Davis, which is ranked No. 9 in the nation's top 10 public universities in rankings released last fall by by U.S. News & World Report. This is the fifth consecutive year that UC Davis has been ranked in the top 10 U.S. public universities.
The UC Davis community includes more than 34,000 students, some 4,100 faculty and other academia, and 17,400 staff. The incoming fall class drew nearly 80,000 applicants, she said.
The UC Davis annual research budget totals more than $750 million. Among the other statistics: UC Davis ranks No. 1 in the world for teaching and research in the area of agriculture and forestry, according to QS World University Rankings.
Katehi said that UC Davis is planning now for the next 30 years, not the next five. "What kind of university will make us proud?" she asked. "What we do today will define us in 30 years."
"Where are we going to be in 30 years?" she asked. "We need to draw a path to get there. We need to know where we're going to be so we can get there."
She thanked the UC Davis Retiree Association for its continuing support. The association was established in 1989 to provide retired academics of UC Davis/UC Davis Health System or other UC campuses living in the Davis/Sacramento area with opportunities for continuing interest in and support for the excellence of UC Davis, according to Sue Barnes, director of the Retiree Center.
- Author: Kathy Keatley Garvey
In a two-hour program, Thorp will share his extensive knowledge of bees and discuss their role as pollinators, providing food and shelter for all living things, a spokesperson said. Interested attendees will be able to learn how to create bee-friendly habitats that support colony growth.
Thorp co-authored the newly published California Bees and Blooms: A Guide for Gardeners and Naturalists with Gordon Frankie, Rollin Coville and Barbara Ertter.
Admission is free and no reservations are required. However, space is limited and those planning to attend should arrive early to get a seat.
Thorp, a faculty member of the UC Davis Department of Entomology (now the UC Davis Department of Entomology and Nematology) from 1964 to 1994, was named the recipient of the distinguished emeriti professor award on Jan. 12 for his scholarly work and service since his retirement. He is a state, national and global authority on pollination ecology, ecology and systematics of honey bees, bumble bees, vernal pool bees, conservation of bees, contribution of native bees to crop pollination, and bees of urban gardens and agricultural landscapes.
Rush Ranch is about 2-1/4 miles south of Highway 12, at 3521 Grizzly Island Road in Suisun City. Directions and a map may be found at www.rushranch.net or at www.solanolandtrust.org. For more information, call (707)422-4491 or (707) 432-0150.
Rush Ranch, a 2,070-acre open space area, is bordered on one side by the Suisun Marsh, a vital component of the San Francisco Bay-Delta Estuary. The property was purchased by the Solano Land Trust in 1988 with a grant from the California Coastal Conservancy.
- Author: Kathy Keatley Garvey
He will be honored in February at a chancellor's luncheon where he will receive a plaque and a cash award.
“Professor Thorp has had an outstanding professional career in the area of pollination ecology and systematics of honey and bumble bees,” said Lyn Lofland, president of the Executive Committee of the UC Davis Emeriti Association. “He has continued his professional contributions since he retired publishing both scientific papers and books. He has continued to teach and guide graduate students providing them with the benefit of his vast experience and knowledge. He also provides expert taxonomic services, identifying thousands of native bee specimens. He has coupled this effort with training numerous field assistants. Professor Thorp matched perfectly with the criteria established for the Distinguished Emeriti Award."
Thorp said it's a great honor to be named a distinguished emeritus. "It is an extra pleasure to be recognized for doing what I love and enjoy."
Thorp, who joined the UC Davis entomology faculty in 1964 and achieved emeritus status in 1994, is a state, national and global authority on pollination ecology, ecology and systematics of honey bees, bumble bees, vernal pool bees, conservation of bees, contribution of native bees to crop pollination, and bees of urban gardens and agricultural landscapes.
A fellow of the California Academy of Sciences since 1986 and a world authority on bumble bees and other native bees, Thorp keynoted the Smithsonian Institution's public symposium on “The Plight of the Bumble Bees” in June of 2009 in Washington D.C., delivering a presentation on “Western Bumble Bees in Peril.” He continues to monitor bumble bee populations in California and Oregon, including Franklin bumble bee (Bombus franklini), which he fears may be extinct. He has sounded the alarm on protecting bumble bees.
Thorp maintains his office and research headquarters in the Harry H. Laidlaw Jr. Honey Bee Research Facility on the UC Davis campus. Among his latest publications: he co-authored two books published in 2014: Bumble Bees of North America: An Identification Guide (Princeton University Press) and California Bees and Blooms: A Guide for Gardeners and Naturalists (Heyday). Of the 20,000 bee species identified worldwide, some 4000 are found in the United States, and 1600 in California.
Thorp chaired the Jepson Prairie Advisory Committee at UC Davis from 1992-2011 (which includes seven years after his retirement). He is still active as a docent leading tours during the tour season. He is also involved in training new docents by providing information on the native bees that pollinate vernal pool flowers.
Thorp spends much of his time in the Bohart Museum of Entomology, which houses collections critical to his bee identification work. He identifies species and regularly volunteers at the open houses and other event.
Thorp is an integral part of The Bee Course, an annual 10-day workshop sponsored by the American Museum of Natural History and held at the Southwestern Field Station near Portal, Ariz. He has taught there since 2002 (the instructors are all volunteers), and even though he is 81 years young, he plans to continue teaching there.
In an email conversation, colleague James Cane of the USDA-ARS Pollinating Insect Research Unit, Utah State University, Logan, said that “Dr. Robbin Thorp should be the first scientist to be cloned, so valuable and broadly integrated are his knowledge about bees and pollination. No one else I know has his combination of skills; normally several people would be needed. Thus, he is a taxonomist of several genera of bees, a competent pollination biologist studying both native bees and honey bees in both natural and agricultural realms (with research experience in several crops), and a conservation advocate for bees. Moreover, I have watched his considerable teaching skills while helping in The Bee Course over the years. There I also get to see what a model human being Robbin is: thoughtful, considerate, a great listener, playful, polite unpretentious, all traits that the students gravitate toward. I have looked to Robbin as a role model for over 30 years, listen carefully to what he has to say, and always look forward to being in his presence. UC Davis is very lucky indeed to have attracted and retained such a fabulous faculty member.”
Colleague Claire Kremen of UC Berkeley credits Thorp with not only identifying more than 100,000 bees for her research since his retirement in 1994, but helping her with research protocol and helping her graduate students identify bees. “Dr. Thorp has contributed in three main ways. First, he has provided expert input into the design of protocols for the research, including assays for pollinator effectiveness, developing citizen science methods, rearing experimental bumble bee colonies, monitoring bumble bee colony properties in the field, and developing pollinator survey methods. Second, he has provided expert taxonomic services, including personally identifying over 100,000 native bee specimens that we have collected during this work, and working with us to develop a bee traits database. Third, he has trained numerous field assistants and graduate students from my lab in different aspects of bee biology. He's spent long hours with many of my graduate students helping them learn to identify bees. He also helped us develop methods and information sheets for teaching field and lab teams to recognize key generic and family characters for identifying bees in the field and sorting them in the lab. He's advised many of my graduate students on different aspects of their work.”
Said Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis: “I have to say that Robbin has been phenomenal. He is more active in research and outreach every year. Regardless of what task is presented to him he is engaged and brings all his experience and knowledge to bear. I don't know many line faculty who are as active in their fields as Robbin is as a retiree. He is always available for museum events and loves to work with the public, particularly kids. I don't know of many pollination ecologists or bee systematists with his level of knowledge.”
Entomologist Katharina Ullmann, who received her doctorate in entomology in 2014 from UC Davis, says that Robbin Thorp is “one of the few people in North America who can identify bees down to the species level. As a result he's in high demand and has identified thousands of specimens for numerous lab groups since his retirement. However, he doesn't just identify the specimens. Instead, he's willing to patiently work through dichotomous keys with you so that you can learn those skills. His ongoing monitoring projects, work as an IUCN specialist, and recent books on bumble bee identification and guide to the bees of California show his commitment to the broader impacts of his research.”
Around the UC Davis campus, Thorp is known as a tireless advocate for pollinator education and outreach. He is often called upon by the Bohart Museum of Entomology and the Häagen-Dazs Honey Bee Garden (both part of the UC Davis Department of Entomology and Nematology), the UC Davis Arboretum and the California Center for Urban Horticulture to participate in their public outreach forums and events.
He spends countless hours connecting people of all ages to the world of insects, especially the pollinators like bumble bees. One of his research projects is monitoring the native bee activity in our department's bee garden, Häagen-Dazs Honey Bee Garden, work that he has done since 2008. In addition, he frequently presents talks at UC Davis and afield, to diverse audiences including UC Master Gardeners, beekeeper groups, and schoolchildren.
Thorp, who calls Michigan his home state, received both his bachelor's degree and master's degree in zoology from the University of Michigan. He received his doctorate in entomology from UC Berkeley in 1964.
Previous recipients of the distinguished award:
2014: Tom Cahill, professor emeritus, physics
2013: Eldredge Moores, professor emeritus, geology
2012: Alex McCall, professor emeritus and former dean, College of Agricultural and Environmental Sciences
2011: Charles Hess, professor emeritus and dean emeritus, College of Agricultural and Environmental Sciences
2008: M. Wayne Thiebaud, emeritus professor, art
- Author: Kathy Keatley Garvey
Of the 20,000 bee species identified worldwide, some 4000 are found in the United States, and 1600 in California.
The book, the first of its kind, profiles some of the most common bee genera found in California gardens; their preferred plants, both native and non-native; and how to attract them.
In addition to the well-known honey bees and bumble bees, the authors spotlight such bees as mining, leafcutting, carpenter, sweat, digger, masked, longhorned, mason and polyester bees.
The honey bee, which provides pollination services valued at $217 billion globally and $20 million in the United States alone, is the most recognizable of the bees, but many are unaware of its non-native status. European colonists brought the honey bee to America in 1622.
California Bees and Bloom, published by the nonprofit Heyday Books in collaboration with the California Native Plant Society, is the work of urban entomologist Gordon Frankie. a professor and research entomologist at UC Berkeley; native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis; insect photographer and entomologist Rollin Coville, who holds a doctorate in entomology from UC Berkeley; and botanist/curator Barbara Ertter of UC Berkeley.
“This book is about urban California's bees: what they are, how and where they live, their relationships with ornamental flowers, and how to attract them to urban gardens,” they wrote. “It was written in the urgency of knowing that bees are critical to the health of our natural, ornamental and agricultural landscapes and that populations of some, perhaps many are in rapid decline.”
“While the book is specific to California, larger insights can be gathered about the role of native bees in developed landscapes (such as agriculture), and native bee conservation,” said Frankie, who researched bees in urban gardens in California for 13 years.
The book traces the first fossilized bee to Burma's Hukawng Valley, where it was lodged in amber approximately 100 million years ago.
The book destroys such myths as:
1. All bees make honey. Fact: Most native bees make no honey at all.
2. Bees die after they sting. Fact: Only the honey bees die; native solitary bees do not.
3. Male bees don't pollinator flowers. Fact: Male engage in pollination, but are not as efficient as most females.
4. Honey bees displace native bees on flowers. Fact: There is no evidence of that. In fact, “Recent research does indicate that interaction between honey bees and native bees results in an increase in the activity and efficiency of honey bees with regard to visiting (and pollinating) crops.”
California's bees differ in size, shape and color, as do the flowers they visit. “The tiniest bees are ant-sized; the largest rival small birds,” they wrote. “Some are iridescent green or blue, some are decked out with bright stripes, some are covered with fuzzy-looking hairs.”
Co-author Gordon Frankie's specialty is behavioral ecology of solitary bees in wildland, agricultural and urban environments of California and Costa Rica. He teaches conservation and environmental issues. He is involved in how people relate to bees and their plants and how to raise human awareness about bee-plant relationships.
Co-author Robbin Thorp, who retired in 1994 after 30 years of teaching, research and mentoring graduate students, continues to conduct research on pollination biology and ecology, systematics, biodiversity and conservation of bees, especially bumble bees. He is one of the instructors at the The Bee Course, affiliated with the American Museum of Natural History and held annually at the Southwestern Research Station, Portal, Ariz. The course is geared for conservation biologists, pollination ecologists and other biologists who seek greater knowledge of the systematics and biology of bees.
“The book is profusely illustrated with photos and drawings of bees and flowers, especially notable are the magnificent close up images of bees by co-author Rollin Coville,” Thorp said.
California Bees and Blooms lists 53 of urban California's best bee attractors identified through the Urban California Native Bee Survey. Among them: aster, bluebeard, catmint, California lilac or Ceanothus, cosmos, California sunflower, red buckwheat, California poppy, blanket flower, oregano, rosemary, lavender, gum plant, and salvia (sage). With each plant, they provide a description; origin and natural habitat, range and use in California; flowering season; resource for bees (such as pollen and nectar), most frequent bee visitors, bee ecology and behavior and gardening tips.
The book offers tips on how readers can “think like a bee.” It devotes one chapter to “Beyond Bee Gardening: Taking Action on Behalf of Native Bees.” In addition, the book provides quotes on bees and/or bee gardens from Extension apiculturist Eric Mussen (retired) of UC Davis: Ellen Zagory, horticulture director of the UC Davis Arboretum; and Kate Frey of Hopland, a designer of sustainable, insect-friendly gardens throughout California and in some parts of the world.
For more data on the book, the authors, and purchase information, access the publisher's website at https://heydaybooks.com/book/california-bees-and-blooms/
For ongoing research on California's bees and blooms, see the UC Berkeley website, www.helpabee.org.