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The blue o rchard bee: A native managed pollinator. Christelle Gu é dot Department of Entomology. Most important insect pollinators: Bees. F eed on nectar and pollen Pollen collecting structures ( scopa, corbicula )
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The blue orchard bee: A native managed pollinator Christelle Guédot Department of Entomology
Most important insect pollinators: Bees Feed on nectar and pollen Pollen collecting structures (scopa, corbicula) Display floral constancy (strong tendency to visit flowers of the same type on a single foraging trip): important for pollination because minimizes pollen wastage and stigma clogging with pollen from other species Andrena Osmiabicornis Jeremy Early Wikimedia Commons http://www.natures-desktop.com/images/wallpapers/1600x1200/insects/bee-collecting-pollen.jpg John B. Pascarella, Sam Houston State University pollinator.info
Why are bees important? Whole foods and Xerces Society "Share the Buzz" campaign (2013)
Bees • At least 25,000 known species of bees • Social vs. solitary, 90% being solitary • ~4,500 of solitary spp. in North America • Wisconsin: ~390 spp. (Wolf and Ascher, 2008) Smallest North American bee (Perdita minima) on largest female carpenter bee T'aiRoulston, University of Virginia Stephen Buchmann
Bees: distinguishing characteristics Bees vs. Wasps Robust Slender Hairy Smooth Flat rear legs Slender legs Feed on nectar and pollen Predators mommammiaFlickr James Cane
Life cycle of a solitary bee Mining bee (Andrena sp.): a year in its underground nest as egg, larva, and pupa before emerging to spend a few weeks as an adult. Photos: Dennis Briggs
Ground-nesting solitary bees • ~70% of native bee species nest underground • Resemble ant-nests from above ground • Nests may be as deep as 3’ Photos: Eric Mader, Matthew Shepherd, Dennis Briggs
Cavity-nesting solitary bees • ~30% of native species nest in cavities • Nest in hollow plant stems, old beetle borer holes, man-made cavities • Nest have tunnel partitions constructed of mud, • leaf pieces, or sawdust • Artificially managed for some crops Photos: Edward Ross, Darrin O’Brien, Matthew Shepherd
Bees for fruit tree pollination • Impediments to bee pollination on fruit trees • Early season; bad weather • Short flowering period: 2-3 weeks • Flowers receptive only few days • Cool temperatures slow pollen germination • ovules might degenerate before fertilized • Incompatibility: bees must move between inter-compatible • cultivars in different rows Christelle Guédot, UW-Madison
Flower morphology ♀ organ ♂ organ ≡ Pistil
Apple pollination • Pollinate king blossoms (first to open, produces larger fruit) • Pollinate blossoms with large amount of compatible pollen for high number of seeds, which relates to fruit size and shape • Size of fruit affected by number fruit produced; thinning might be required http://appleharvester.blogspot.com/2011/05/king-blossom.html Christelle Guédot, UW-Madison
Back Front Cell1 Egg Mud partitions Provision The blue orchard bee • Osmialignaria, a native • Solitary but gregarious • Nest in pre-existing cavities • Only females provision nest • Collect nectar and pollen for provision • Collect mud for nesting material
The blue orchard bee Females Male Female 0.4 - 0.6” long Prepupa 5th instar larva inside coccon White pupa Black pupa Adult
Life cycle of blue orchard bee Eggs hatch, larvae grow into pupae Late March April - May June July - Aug Sept - March Dormant adults
Identifying females vs. males • Males smaller than more robust females • Males have longer, more slender antennae • Males have more facial hair • Males do not have scopa, females do http://seabrookeleckie.com/
Life history • Fecundity: 10 - 20 eggs / nesting female (2.5 - 6 ♀ eggs) • Longevity adult females: ~20 days • Females build ~ 2-4 nests in lifetime • Emergence: - males emerge 24-48 hrsafter warming - females emerge 1-3 days later
Why the blue orchard bee? discoverlife.org: Osmia lignariadistribution • Native • Commercial use in 1970’s • Forages in cool weather > 54°F • Visits many tree species: • almonds, apple, pear, cherry, apricot,… Designed by The Polistes Corporation
Why the blue orchard bee? Foraging behavior and pollination effectiveness % Stigmacontact Christelle Guédot, UW-Madison http://www.ars.usda.gov/Research/docs.htm?docid=18333
Why the blue orchard bee? • Blue orchard bees readily move from tree to tree and row to row • Facilitate cross-pollination, rather than pollination within a tree or within a cultivar • Preference for fruit tree pollen: 85-100% Dandelion http://www.swcoloradowildflowers.com Golden currant
Why the blue orchard bee? • Active at low light levels and low temperatures • 33+ hours foraging in 5 days • 15+ hours by honey bees • Usual foragingrange: 300-600 ft • Max. foragingrange: 1,300 ft • Homingability: 4,000 ft
Apple yield with blue orchard bee Commercial Apple Orchard, Utah 53% increase
Why the blue orchard bee? Commercial cherry orchard, Utah * Freezing event; ** missed timing on BOB release; ***high bee predation by birds
Number of females Optimal number of nesting females for adequate pollination In comparison, need 1 - 2.5 honeybee hives / acre (typically 30,000 - 50,000 workers / hive)
Pollination efficiency • Flower efficiency and fidelity • 75 flowers per “load” of pollen and nectar • 15-35 loads per provision • 75 X 25 (avg.) = 1,875 flower visits per provision • Female provisions 7 – 12 cells in her life • A single female visits 10,000-20,000 flowers in her lifetime! • Remember: 85-100% orchard flower pollen Christelle Guédot, UW-Madison
How to manage the blue orchard bee • What do you need to haveblue orchard bees in your orchard? • Care, attention, enthusiasm • Bee stock • Nesting equipment • Appropriate storage facility • Proper handling http://www.sare.org/Learning-Center/Books/How-to-Manage-the-Blue-Orchard-Bee
Nesting shelters • Attach shelter on tree or fence post • Orient SE for longer foraging activity (and more attractive to nesting females) James Cane, USDA ARS Shelter with wooden blocks and chicken wire
Nesting blocks Reeds Prefer wood blocks Paper straws in cavities help for handling and storage Wafer boards
Nesting cavities • 19/64” (7.5 mm) hole diameter • 6” (15 cm) long • Plan on 3-5 nesting cavities per female released
Nesting material • Mud is a vital nesting material • Clayey mud, not sand or loam • Need safe place for gathering mud, within 20-50ft. of nest
A typical BOB season • Example for Northern Utah • March/April • About two weeks prior to expected bloom: • Check flower development • Check weather forecast
A typical BOB season • 2) March/April • Set up nesting materials and mud sources • Incubate bees at 72-76°F (22-25°C) • Emerged bees can be held at 37-41ºF for ~a week
A typical BOB season 3) March/April Release BOB population (200-300 females + 400-600 males per acre for full pollination in almonds, cherries, apples, and pears)
A typical BOB season • 4) May/June • Retrieve nesting materials • Move nests to summer storage (avoid excessive heat, direct sun) • Take measures to avoid parasitism Adult female chalcidwasp, Monodontomerus Blue orchard bee nests by black light trap Note large numbers of drowned Monodontomerusin tray Adult female chalcid wasp, Melittobiachalybii
A typical BOB season • 5) June through August • Monitor development with monthly development checks • Select 10 male cocoons from different nests
A typical BOB season • 6) Mid/late September • Move nests to winter storage (refrigerator) • Check small sample of females from different nests to be sure that all adults • Best if population held for 1 week at 55°F before being placed in artificial wintering at 39°F • Require minimum of 3 months wintering: adults go dormant (diapause)
A typical BOB season • 7) November/December • Quantify population • Remove parasites and diseased bees (now dead) • Prepare nesting materials for the following season Hairy-fingered pollen mite, Chaetodactyluskrombeini Recently emerged male covered with migratory nymphs of hairy-fingered mite Chalkbrood fungus
Summary • Blue orchard beesare superb orchard pollinators • BOBs can be usedalone or along withhoney bees • Easy management • Bees are safe
Acknowledgements • Jordi Bosch • Theresa Pitts-Singer • William P. Kemp • USDA-ARS Beelab