- Author: Kathy Keatley Garvey
Take Benicia, Solano County. Its little hot spots near the Carquinez Strait--think trees growing near sun-warmed asphalt--yield early almond blooms, often as early as New Year's Day.
At the Matthew Turner Park in Benicia, today, honey bees buzzed around the almond blossoms, gathering pollen and nectar. But the honey bees were not alone.
Yellow-faced bumble bees, Bombus vosnesenskii, were foraging, too. It's always a treat to see honey bees in the almonds, but it's a double treat to see a bumble bee.
Pollination of California's almond acreage is as intense as it is huge. The 2016 almond acreage totaled 1.2 million acres--940,000 bearing and 300,000 acres non-bearing, according to a report issued in April 2017 by the California Department of Food and Agriculture, in cooperation with the National Agricultural Statistics Service of the U.S. Department of Agriculture. This year, California has more than a million acres of bearing almonds, and each acre requires two bee hives for pollination. The leading almond-producing counties? Kern, Fresno, Stanislaus, Merced and Madera.
Solano County, of course, doesn't make the list, but when you want to see the early almond blooms, it's the place to "bee."
Which reminds us of the research, Synergistic Effectgs of non-Apis Bees and Honey Bees for Pollination Services, published by an international team of scientists in the Jan. 10, 2013 edition of The Proceedings of the Royal Society B. The researchers, including pollination ecologist Neal Williams of UC Davis, found that honey bees are more effective at pollinating almonds when other species of bees are present.
When blue orchard bees and wild (non-managed) bees such as bumble bees, carpenter bees and sweat bees, are foraging in almonds with honey bees, the behavior of honey bees changes, resulting in more effective crop pollination, said lead author Claire Brittain, then of the Neal Williams lab. She earlier worked as a post-doctoral fellow at Leuphana University of Lüneburg, Germany.
“These findings highlight the importance of conserving pollinators and the natural habitats they rely on,” Brittain told us in a news release. “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.”
Agroecologist Alexandra-Maria Klein, now a professor at Leuphana University, served as the project lead while a postdoctoral fellow in the UC Berkeley lab of conservation biologist/professor Claire Kremen. In fact, Klein and Kremen initiated the project in 2008 and continued working on the project together in 2009 and 2010. Williams joined the team in 2010.
Native pollinator specialist Robbin Thorp, now a distinguished emeritus professor of entomology at UC Davis, identified 50 different species that the team found. They included bumble bees, small carpenter bees, sweat bees, digger bees, mining bees and blue orchard bees.
Take a look around you during the almond pollination season. The honey bees are not alone.
- Author: Kathy Keatley Garvey
Ironically, it occurred the first day of National Pollinator Week.
Sujaya Rao, an Oregon State University (OSU) entomologist working the case, will be speaking on "The Buzz on Native Bumble Bees in Western Oregon: Why They Thrive and Die," from 12:10 to 1 p.m., Wednesday, May 18 in Room 230 of Wellman Hall. The talk, hosted by the UC Davis Department of Entomology and Nematology, is open to all interested persons.
Scientists attributed the massive bumble bee die-off to the active ingredient Dinotefuran, a neonicotinoid.
The Oregon Department of Agriculture (ODA) then put temporary restrictions on the use of 18 pesticides containing Dinotefuran.
The Xerces Society for Invertebrate Conservation was appalled by the die-off, as many of us were--and still are. Mace Vaughan, the Xerces Society's pollinator conservation director, said in a press release: “To our knowledge, this incident is the largest mass poisoning of bumble bees ever documented, and thankfully ODA is taking the issue very seriously. After interviewing the landscaping company that maintains dozens of ornamental trees around the Target parking lot, ODA investigators learned that the pesticide Dinotefuran had recently been applied. Investigators confirmed that Dinotefuran, sold under the trade name ‘Safari,' belongs to a class of insecticides called neonicotinoids that have been linked to bee deaths in recent years."
“Because neonicotinoids are long-lasting in plant tissues and can be found in flower nectar and pollen, and because they have been implicated in the global decline of honeybees, there have been growing concerns about their safety for pollinators,” the Xerces Society related in the press release.
Scott Black, executive director of the Xerces Society, noted that the pesticide was applied to the tree while it was flowering, an action that violates the product's instructions. “Beyond the fact that a pesticide was applied to plants while they were attracting large numbers of bees, in this case the pesticide was applied for purely cosmetic reasons. There was no threat to human health or the protection of farm crops that even factored into this decision.”
Rao, an OSU professor and field crop entomologist, specializes in pest management in grass seed and rotational crops, as well as native bee pollinators in agricultural and native landscapes. On her website, she lists her native bee research objectives as:
Determine the diversity and abundance of native bees in diverse cropping systems and surrounding habitats, and evaluate the impacts of bumble bees and honey bees in pollination. Specific areas of research:
- Red and arrow leaf clover
- Blueberries
- Cranberries
- Meadowfoam
It's difficult to think of 50,000 bumble bees dying.
How long has it been since you've seen a bumble bee? Last weekend a yellow-faced bumble bee, Bombus vosnesenskii, buzzed into our Vacaville yard and foraged in the foxgloves.
Then last week, another bumble bee, the black-faced Bombus californicus, frequented the "Purple Ginny" sage (Salvia coahuilensis) in the Häagen-Dazs Honey Bee Haven on Bee Biology Road, UC Davis. Operated by the UC Davis Department of Entomology and Nematology, the half-acre bee garden is open from dawn to dusk.
Now if we could just do more to protect the pollinators...
