The wild bee research co-authored by 58 bee scientists and published today (June 16) in Nature Communications is drawing a lot of attention--and well it should.
Pointing out that wild bee diversity is declining worldwide at unprecedented rates, the researchers said steps must be taken to conserve them--and not just those that are the main pollinators of agricultural crops.
"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. "
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.
Wrote the researchers in their abstract: “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. 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.
As an aside, we certainly hope that this global research packs a social media wallop and leads to efforts to protect and preserve our wild bees. Unfortunately, many people never think about wild bees. It's "out of sight, out of mind," not "absence makes the heart grow fonder."
We'd all do well to take a look at the amazing macro bee images by Sam Droege, head 'of the bee inventory and monitoring program at the U.S. Geological Survey (USGS). His work has been featured in publications all over the world. Among the latest: National Geographic. See his USGS work posted on Flickr. And check out his book, An Up-Close Look at Pollinators Around the World, co-authored by Laurence Packer.
Absence CAN make the heart grow fonder...
Think of them as "the good guys" and "the good girls."
Insects such as lacewings, lady beetles and flower flies.
We're delighted to see that the Xerces Society for Invertebrate Conservation has just published a 250-page book on "Farming with Native Beneficial Insects."
The book advocates the use of beneficial insects to prey upon crop pests, thus "reducing or eliminating the use of pesticides," say co-authors Eric Lee-Mäder, Jennifer Hopwood, Mace Vaughan, Scott Hoffman Black, and Lora Morandin.
"This comprehensive guide describes how to recognize these insects and their habitat, and how to evaluate, design, and improve habitat for them," they write. They offer specific solutions, including native plant field borders, mass insectary plantings, hedgerows, cover crops, buffer strips, beetle banks, and brush piles.
The much-acclaimed book, available for purchase on the Xerces website, is drawing well deserved accolades, including this one from Claire Kremen, professor and co-director of the Berkeley Food Institute, University of California, Berkeley:
“If you are a grower or a backyard gardener, this is a ‘must have.' Readable and filled with gorgeous photos and handy charts, this book provides reams of information about how to get the upper hand on your pest issues with reduced or no pesticide use.”
Xerces officials say the release of Farming with Native Beneficial Insects coincides with its launch of a new nationwide workshop series on natural pest control: the Conservation Biological Control Short Course. The course, to begin in the West and Midwest, "provides farmers, crop consultants, and government farm agency staff with a comprehensive, hands-on training in the natural pest management strategies described in the book. A similar workshop model previously offered by Xerces trained tens of thousands of people in farm communities across the U.S. to conserve bees and restore pollinator habitat, and helped facilitate the restoration of more than 100,000 acres of wildflower habitat for bees."
Speaking of "the good guys" and "the good girls," be sure to read the UC Statewide Integrated Pest Management Project's website on beneficial insects and natural enemies. The natural enemies include assassin bugs, bigeyed bugs, brown lacewings, convergent lady beetles, damsel bugs, dustywings, syrphid flies and twicestabbed lady beetles.
What is Integrated Pest Management (IPM)? "Integrated pest management uses environmentally sound, yet effective, ways to keep pests from annoying you or damaging plants. IPM programs usually combine several pest control methods for long-term prevention and management of pest problems without harming you, your family, or the environment. Successful IPM begins with correct identification of the pest. Only then can you select the appropriate IPM methods and materials."
UC IPM points out:
- Many pests can be managed without the use of pesticides.
- Use pesticides only if nonchemical controls are ineffective and pests are reaching intolerable levels.
- Use pesticides in combination with the methods described above.
- Choose pesticides carefully. Use the least toxic, most effective material to protect human health and the environment.
- Examples of least toxic insecticides include:
- Oils; and
- Microbials such as Bacillus thuringiensis (Bt) and spinosad.
The more we learn about pests and the natural enemies of pests, the oft-heard quote, "Keep your friends close and your enemies closer" rings quite true. The more we learn about our enemies, the less likely they will be able to harm us.
We can expect some exciting research to emerge from the U. S. Department of Agriculture's Specialty Crop Research Initiative (SCRI).
And UC Davis pollination ecologist Neal Williams, an assistant professor in the Department of Entomology, is a part it.
Williams and postdoctoral fellow Claire Brittain of the Williams lab will be participating in the SCRI's annual team and advisory committee meeting, to be held Jan. 17-19 in Gainesville, Fla.
Williams is a co-project director of Aspire Project: Augmenting Specialty Crop Pollination Through Integrated Research and Education for Bees, a coordinated agricultural project funded by SCRI. Williams serves as the project leader for habitat enhancement for bees and a co-leader of a project seeking alternative managed bees for almonds.
The meeting will be the first “all-hands-on-deck” meeting to discuss plans for the first field season; to coordinate collection and curation techniques; and to obtain feedback from the Advisory Committee Tentative Plan, according to Rufus Isaacs, berry crops entomology Extension specialist at Michigan State University, Lansing, Mich.
Isaacs directs the Aspire Project for Bees and is the principal investigator of the $1.6-million SCRI grant. (See news release.)
In addition to Williams, the co-project directors are Theresa Pitts-Singer, research entomologist, USDA-ARS Pollinating Insects Research Unit, Department of Biology. Logan, Utah; Mace Vaughan, pollinator program director, Xerces Society, Portland, Ore; and Mark Lubell, Sociology of Sustainability, UC Davis Department of Environmental Science and Policy.
Project Team members are investigating the performance, economics, and farmer perceptions of different pollination strategies in various fruit and vegetable crops. These include complete reliance on honey bees, farm habitat manipulation to enhance suitability for bees, and use of managed native bees alone or in combination with honey bees. The Project Team has a strong outreach focus, said Isaacs, and will deliver its findings to specialty crop agriculture through various diverse routes of traditional and new media, including the Aspire website.
“Our long-term goal is to develop and deliver context-specific Integrated Crop Pollination (ICP) recommendations on how to most effectively harness the potential of native bees for crop pollination,” says Isaacs on the Aspire website. “We define ICP as: the combined use of different pollinator species, habitat augmentation, and crop management practices to provide reliable and economical pollination of crops. This approach is analogous to Integrated Pest Management in that we aim to provide decision-support tools to reduce risk and improve returns through the use of multiple tactics tailored to specific crops and situations. By developing context-specific ICP programs, this project will improve sustainability of U.S. specialty crops and thereby help ensure the continued ability of growers to reap profitable returns from their investments in land, plants, and other production inputs.”
The project objectives are five-fold:
- to identify economically valuable pollinators and the factors affecting their abundance.
- to develop habitat management practices to improve crop pollination.
- to determine performance of alternative managed bees as specialty crop pollinators.
- to demonstrate and deliver ICP practices for specialty crops.
- to determine optimal methods for ICP information delivery and measure ICP adoption
Two other UC-affiliated scientists are involved with the Aspire program: Karen Klonsky, Cooperative Extension specialist with the UC Davis Department of Agricultural and Resource Economics; and Claire Kremen, pollination ecologist and professor at UC Berkeley.
All hands on deck!
An international research team has been researching honey bee pollination of almonds in the three-county area of Yolo, Colusa and Stanislaus since 2008, and what these scientists have discovered is astounding.
The bottom line: Honey bees are more effective at pollinating almonds when other species of bees are present.
The research, “Synergistic Effects of Non-Apis Bees and Honey Bees for Pollination Services,”published in the Jan. 9th edition of the Proceedings of the Royal Society, could prove invaluable in increasing the pollination effectiveness of honey bees, as demand for their pollination service grows.
So when honey bees are foraging with blue orchard bees and wild bees (such as bumble bees and carpenter bees), the honey bee behavior changes, resulting in more effective crop pollination, says lead author Claire Brittain, a former post-doctoral fellow from Leuphana University of Lüneburg, Germany and now associated with the Neal Williams lab at the University of California, Davis.
“These findings highlight the importance of conserving pollinators and the natural habitats they rely on,” Brittain says. “Not only can they play an important direct role in crop pollination, but we also show that they can improve the pollination service of honey bees in almonds.”
Where did this project originate? In the UC Berkeley lab of conservation biologist/professor Claire Kremen, recipient of a MacArthur Foundation (Genius) Award. Also an associate of the UC Davis Department of Entomology, Kremen works closely with the department's bee scientists at the Harry H. Laidlaw Jr. Honey Bee Research Facility.
Brittain, Kremen, Klein and pollination ecologist Neal Williams, assistant professor of entomology at UC Davis (he joined the team in 2010), co-authored the research.
“This is one of our first demonstrations on how to increase the efficiency of honey bee pollination through diversification of pollinators,” Williams said, pointing out that “With increasing demands for pollination-dependent crops globally, and continued challenges that limit the supply of honey bees, such strategies to increase pollination efficiency offer exciting potential for more sustainable pollination in the future.”
Yes. California’s almond acreage is rapidly increasing. Seems like only a few years ago it was 600,000 acres and now it totals 800,000. Each acre requires two bee hives for pollination, but honey bee-health problems have sparked new concern over pollination services.
As Kremen says: “Almond is a $3 billion industry in California. Our study shows that native bees, through their interactions with honey bees, increase the pollination efficiency of honey bees--the principal bee managed for almond pollination--and thus the amount of fruit set.”
What's next? “The project is ongoing and we plan to investigate further the mechanism behind the increased effectiveness of honey bees when other bees are present,” Brittain says. “We are also going to be looking at how to enhance floral resources for wild bees in almond orchards.”
Meanwhile, watch Professor Klein's UC Davis Department of Entomology seminar, presented in February 2010, when she lectured on “Can Wild Pollinators Contribute, Augment and Complement Almond Pollination in California." It drew widespread interest and a capacity crowd. Click on this link: https://admin.na4.acrobat.com/_a841422360/p37649788/ to hear more.
It's not your average garden variety calendar.
It's absolutely bee-utiful.
Native bees reign supreme in “Garden Variety Native Bees of North America,” a calendar produced by University of California alumni as a benefit for two non-profit organizations.
The perpetual calendar, the work of native bee enthusiast Celeste Ets-Hokin and entomologist/photographer Rollin Coville, both of the Bay Area, features native bees found throughout North America, including the leafcutter bee, bumble bee and sweat bee.
The macro photography is simply stunning. Through these photos, you can get up close and personal with bees you may never have even noticed. The ultra green sweat bees are especially spectacular.
Native pollinator specialist Robbin Thorp, emeritus professor of entomology at UC Davis, provided “considerable insight into the biology and ecology of several native bee genera,” said Ets-Hokin.
Also contributing extensively were UC Berkeley faculty members Gordon Frankie and Claire Kremen. Frankie shared his extensive knowledge of native bees in urban gardens. Kremen provided crucial information on native bee crop pollination services, based on her studies in Yolo County.
A portion of the proceeds will benefit the Great Sunflower Project, a national pollinator monitoring and conservation program based in San Francisco, and the Portland, Ore-based Xerces Society for Invertebrate Conservation, which protects native bees and their habitat throughout the United States.
Each native bee comes complete with information, such as the genus, common name, pollen/nectar sources, emergence time, nesting habit, and distinguishing characteristics.
For instance, you'll learn that bumble bees are excellent crop pollinators; they pollinate such crops as tomatoes, cranberries and blueberries better than honey bees.
You can attract bumble bees to your own garden by planting such pollen/nectar sources as giant hyssop (Agastache); manzanita (Arctostaphylos), ceanothus (Ceanothus); California poppy (Eschscholzia), sunflower (Helianthus); and beard tongue (Penstemon).
It's all there--all there on the calendar.
Coville, who received his doctorate in entomology from UC Berkeley in 1978, has been photographing insects and spiders for more than 25 years. He is collaborating with Thorp and Frankie on a number of projects, including a book on urban bees. It's due out next year.
Ets-Hokin, a UC Berkeley zoology graduate, devotes her time to the public awareness and conservation of native bees. For the past several years, she has collaborated with the Alameda County Master Gardeners in establishing a native bee demonstration garden at Lake Merritt, Oakland.
Coville takes many of his images there and now he has Ets-Hokin hooked on photography.
Preview the calendar here. Want to order one or more? Go to the printer's website.