-
1.
The Buzz with Bees: Native
and Managed Pollinators
Hannah Gaines Day
Department of Entomology
University of Wisconsin, Madison
-
2.
Protecting wildlife through the conservation of invertebrates and
their habitat since 1971.
Major Programs:
• Endangered species
• Aquatic invertebrates
• Pollinator conservation
www.funet.fi
Advocacy, Education, Restoration, and Applied Research
-
3.
Outline
• The importance of pollinators
• Biology and natural history of bees
• Resource requirements of native bees
• Crop pollination by bees
• Threats to native bees
• Native bee research at UW
• Native bee conservation strategies
-
4.
Pollination
• Transfer of pollen from anthers to stigma
• Wind, gravity, or animal mediated
© Bruce Newhouse
-
5.
Pollinators
• Birds, bats, bees, moths, butterflies
-
6.
Pollinators
• Birds, bats, bees, moths, butterflies
• Bees are the MOST IMPORTANT pollinators
– Actively collect pollen
– Floral constancy
– Branched hairs
-
7.
• 85% of all flowering plants
• 35% of global crop production
R. Winfree
How important are bees?
-
8.
Poor fruit set resulting from poor pollination
-
9.
One in every three bites you eat is
dependent on insect pollination.
-
10.
What is a bee?
• Hymenoptera
– Ants, bees, wasps
•6 legs, 4 wings
• Vegetarian
– Provision nests with pollen
• Great pollinators!
– Pollen sticks to feather-
like hairs
-
11.
Bees versus wasps
• Carnivorous
• Simple hairs
• More aggressive
• Examples: yellow jackets,
hornets, paper wasps
-
12.
Bees versus flies
• Feed on decaying matter,
feces, and blood
• Also feed on nectar
• 2 wings, short stubby
antennae
• Prominent eyes
• Examples: house flies,
hover flies
-
13.
Native bees versus honey bees
• Single, non-native species
• Perennial colony with queen
• Wax hives
• Produce honey
-
14.
Honey bees are not native, but
• Generalist pollinators
• “Easy” to manage
• Work well with modern agricultural system
-
15.
How many bees are there?
• ~20,000 species worldwide
• ~4000 species native to North America
• ~500 species native to Wisconsin
-
16.
Photos: James Cane; Steve Javorek (Ag Canada); Edward S. Ross
Honey bee (Apis mellifera)
Bumble bee (Bombus edwardsii) Leafcutter bee (Megachile sp.)
Polyester bee (Colletes sp)
-
17.
Photos: Bruce Newhouse; Edward S. Ross; Mace Vaughan; USDA-ARS/Jack Dykinga
Metallic sweat bee (Agapostemon sp.) Yellow-faced bee (Hylaeus sp.)
Mason bee (Osmia sp.) Sweat bee (Halictus sp.)
-
18.
Metallic sweat bee (Agapostemon sp.)
Mason bee (Osmia sp.)
Sunflower bee (Svastra sp.)
Long-horned bee (Mellisodes sp.)
Photo: Bob Hammond, CSU Coop Ext
Photo: Bob Hammond, CSU Coop Ext
Carpenter bee (Xylocopa sp.)
Photo: Gene Barickman, IL NRCS
-
19.
Photo: Stephen L. Buchmann
-
20.
Social behavior of bees
• Solitary (majority of species)
• Social (only 10%)
– Honey bees (NOT native)
– Bumble bees
-
21.
Solitary bee life cycle
Spring
Summer
Fall
Winter
(Photos: Dennis Briggs)
-
22.
Social bee life cycle (bumble bee)
Spring
Summer
Fall
Winter
-
23.
Nesting behavior of bees
Ground
Stem
S. Camarzine
Cavity
-
24.
Ground nesting (~70% of bees)
-
25.
P.Westrich
Ground nesting (~70% of bees)
K. Ullmann
-
26.
© Edward Ross
Stem nesting (~30% of bees)
www.pestweb.com
www.warrenphotographic.co.uk
Leaf-cutter bees (Megachile sp.)
-
27.
Stem nesting bees
• Leaf-cutter bees (Megachile addenda)
-
28.
Mud cap closure
Larva Pupa Adult
Pollen mass Egg Mud wall
Cross-section of silk cocoons
Stem nesting bees
-
29.
Stem nesting bees
www.agf.gov.bc.ca
T. Stoehr
• Mason bees (Osmia sp.)
-
30.
S. Camarzine
Cavity nesting (bumble bees)
K. Ullmann
-
31.
Cavity nesting (bumble bees)
• 45 species in North America
• Annual colony with 100-300 workers
• Specialist pollinators of red clover,
blueberry, cranberry, eggplant, tomato
Photos:Eric Mader, Elaine Evans
-
32.
Resource requirements
• Flower availability
– Early spring through fall
• Nesting resources
– Undisturbed soil, woody habitat, or nest boxes
-
33.
Landscapes
• Some landscapes already provide adequate
resources.
A. Bennett
-
34.
Landscapes
• Some do not.
A. Bennett
-
35.
Why is the landscape important?
• Central place foragers
• Flight distance proportional to size of bee
-
36.
Crop pollination by bees
• One in every three bites…
-
37.
Crop pollination by bees
Photo: USDA-ARS/Scott Bauer
-
38.
US Agriculture
www.gallery.photo.net
-
39.
Honey bee decline
• Mites, disease, Colony Collapse Disorder
Photo: USDA-ARS/Scott Bauer
Varroa mite
-
40.
Causes of Colony Collapse Disorder
• Disease/pathogen?
• Israeli Acute Paralysis
Virus?
• New strain of Nosema?
• Pests?
• Poor diet?
• Insecticide exposure?
• Stress?
• Not cell phones or
Bt Corn
-
41.
Honey bee rental rates (CA)
1995-2005
-
42.
Honey bee rental rates (CA)
1995-2005, plus almonds, 2006-2008
2006
2007
2008
-
43.
How does the honey bee decline
effect Wisconsin farmers?
• Hive fees increase
• Hive quality decreases
-
44.
Native bees and crop pollination
• Active earlier in season
and day
• Collect both pollen
and nectar
• Buzz pollination
• No rental fees
• Keep honey bees
moving
• Not susceptible to
honey bee diseases
-
45.
Significance to agriculture
- Native bees provide insurance against
honey bee decline
- Efficient crop pollinators
R. Winfree
-
46.
Photo: Bob Hammond, CSU Coop Ext
-
47.
Native bees and crop pollination
• More efficient than honey bees
• Active earlier and in cooler weather
• Not effected by honey bee diseases
• Free!
-
48.
Native bees also in decline
© Derrick Ditchburn
© Johanna James-Heinz
© Jodi DeLong
© Peter Schroeder
Yellow-banded
Franklin’s
Rusty-patch
Western
-
49.
Images: The Xerces Society
Native bees also in decline
- Yellow Banded Bumble Bee (Bombus
terricolla) once very common, now gone
-
50.
What threats do they face?
- Disease and pathogen from
commercially reared bumble bees
- Agricultural intensification
- Pesticide exposure
- Loss of habitat
-
51.
Bees and Wisconsin agriculture
-
52.
Bee researchers at the UW
Brian Spiesman
Rachel Mallinger David Lowenstein
Hannah Gaines Day
-
53.
Native bees in cranberry
– 182 species of bees
– More woodland = more bees
-
54.
Cage Treatment
p = 0.007
Yield(bbl/acre±SE)
Closed Open
-
55.
Native bees in apple
•~80 species of bees
•>50% of all visits to apple flowers
•Habitat diversity -> bee diversity
-
56.
Native bees in apple
-
57.
Native bees in cucumber
•65 species
•More natural habitat = more bees
-
58.
Native bees in grassland
More flowers = more bees
-
59.
Native bees in biofuels
Werling et al. PNAS 2013
Greater plant diversity = more bees, more pollination
-
60.
Pollinators need habitat
Photo: Rollin Coville
-
61.
How can you provide habitat?
• Nesting resources
• Floral resources
-
62.
Nesting resources
• Artificial nest boxes
K. Ullmann
K. Ullmann
Photos: Matthew Shepherd; NRCS/Lynn Betts
-
63.
Nesting resources
• Bare, undisturbed ground
Photo: Bob Hammond, CO Coop Ext
-
64.
Nesting resources
• Natural habitat
© NRCS Lynn Betts© Mace Vaughan
-
65.
Floral resources - diversity
-
66.
Foraging resources - timing
TAXA APRIL MAY JUNE JULY AUG SEP OCT
Colletes (inaequalis,
validis)
Andrena
Augochlora pura
Augochlorella striata
Halictus (females)
Lasioglossum (females)
Osmia
Bombus
© Data from Steve Javorek, Agriculture Canada
• Bee flight periods in Nova Scotia
-
67.
Floral resources - timing
• Spring ephemerals
-
68.
Floral resources
• Systemic pesticide use in commercial
nurseries
-
69.
Foraging resources
• How to select good bee plants
– Locally native plants are better for native bees
– Minimum of 3 blooming plants at all times
throughout the season (spring, summer, fall)
– PLANT IN CLUMPS FOR BEST RESULT!
-
70.
Protecting the bees
• Restrict insecticide use
•Use active ingredients
with least impact on
bees
•Spray at night
•Consider alternatives
•Companion planting
•Pheromone traps
and baits
•Restrict herbicide use
K. Ullmann
-
71.
Native bee conservation
• Plant diverse floral plantings that bloom
throughout the season
• Create and protect nesting sites (nest boxes,
bare ground, natural areas)
• Limit chemical use in your garden AND ask at
the nursery where you buy plants if plants
have been treated with SYSTEMIC pesticides
-
72.
Take home message
• Bees are important
– 1 in 3 bites you eat depends on bees!
• Relying on a single pollinator species is risky
– Decline threatens our food supply
• Plant flowers!
-
73.
Further resources
The Xerces Society (www.xerces.org)
-
74.
Further resources
The Xerces Society (www.xerces.org)
– Pollinator Conservation Resource Center
•Plant lists
•Conservation
guidelines
•Pesticide
guidelines
-
75.
Further resources
Insect identification
• Bug Guide (www.bugguide.net)
• Discover Life (www.discoverlife.org)
-
76.
Hannah Gaines Day
hgaines@gmail.com
774-392-0498
The information contained in this presentation was prepared by the Xerces Society for Invertebrate Conservation. Formed in 1971, the Society is at the forefront of pollinator conservation, harnessing the knowledge of scientists and public enthusiasm to educate, advocate, and implement conservation efforts across the country.
The Xerces Society is named after the now extinct Xerces Blue butterfly, the first butterfly to go extinct in North America due to human activities.
Before I get into the details of my research, I wanted to briefly talk about bees in general. First of all, what makes a bee a bee?
Beginning in the upper left hand corner is our non-native European honey bees, but our native bees come in a wide range of colors and sizes, here are some contrasting examples…
…to over an inch in length like the carpenter bee here on the right.
Adult for only 4 weeks
Unlike honey bees which exist in perennial colonies, bumble bees form annual colonies formed in the spring by a solitary queen. This comparison is similar to that of a perennial plant vs. an annual one. In the life cycle diagram above, the yellow bee is the queen. After raising her initial brood, they take over the foraging and nest construction duties, and the queen stays inside the nest laying eggs. Late in the season the colony will raise new queens which leave the nest and hibernate in leaf litter of loose soil alone over the winter. The old queen and the old colony dies in the fall.
Finally, many additional materials are available from the Xerces Society. Among these are fact sheets on the role of native pollinators, artificial nest construction and management guidelines, farm management booklets, and links to various regional resources. Most Xerces Society publications are available as free downloads on our website.
The life cycle of these solitary tunnel-nesting bees is similar to that of solitary ground-nesting bees, however the brood cells are typically constructed in a linear arrangement separated by a series of mud or leaf partitions. Many people have heard of mason bees and leafcutter bees, both are examples of tunnel-nesting solitary bees.
NJ example
CA example
Price for honey bee rentals for crop pollination likely to rise: already reported higher for blueberries in New England and at least one big supplier in PA doesn’t have enough bees to fulfill apple contracts in NY.
Fewer honey bees available
Over 50% decline in number of managed hives since 1950
70-100% decline in feral colonies since the 1990s
Causes: Disease, pests, honey prices, and Colony Collapse Disorder
In 2006-7, about 25% of beekeeping operations in the U.S. lost an average of 45% of hives.
CCD losses in 2007-09 were similar.
We still do not know exactly what is causing CCD. Right now, the following issues are still being explored for their potential role in CCD.
Disease: We are familiar with Nosema apis (typically sickens hive during Fall/Winter), but new Nosema = N. ceranea (seems to hit in the summer and acts faster)
Pests: Already causing significant declines, could be helping to spread disease or weaken colonies
Insecticides: Still being investigated. In some countries, the neonicitinoids have been implicated, but no strong evidence of CCD link
Stress: Comes up often, and might be a factor, but certainly not the cause (honey bees have been shipped around for thousands of years, since the time of the Pharaohs in Egypt)
Cell phones: One of the primary reasons the general public knows about declining honey bees is because of the purported linkages between cell phone towers and bees abandoning their hives…totally Bogus!
Bt: very unlikely.
Poor diet and insecticides are two primary areas where the NRCS can help, either improving habitat or increasing use of IPM and/or conservation biological control.
This graph illustrates the average cost of honey bee hive rentals for several key California crops. Note that almonds (represented by the top bar) rose from an average of $45/hive in 1995, and by 2005, as we saw bee shortages beginning to increase, the average cost rose to $75/hive.
And then, as colony collapse disorder hit the nation, this is what happened to the average hive costs that almond growers were paying…
Average hive rental prices rose to almost $200. So in just over a decade, the almond industry alone has experienced a nearly 4 fold increase in pollination costs. Keep in mind that there are over 600,000 acres of almonds in California, and the orchards are typically stocked at a rate of 2 hives per acre. At that stocking rate a little over half of all the honey bee hives in the U.S. are required for this one industry.
Our native bees, in many cases, are on a bee-for-bee basis significantly more efficient pollinators than honey bees.
From a crop security perspective it is essential that we begin thinking about ways to diversify the ecological service of pollination. Our best available alternative to honey bees are the wild native bees that have been in the background all along. Photo of squash blossom full of male squash bees (Peponapis sp).
Many of our native bees are also in decline. Of particular importance are members of the subgenus Bombus. This is a closely related group of “sister species” that range across the country. Once they accounted for some of the most common bees in their range, now they are nearly impossible to find, especially in agricultural areas.
As an example, the yellow banded bumble bee in a 1995 survey was the most common bee found in northern Wisconsin where it was a highly valued pollinator of cranberry. In a follow-up survey in 2005 it constituted less than 1% of all the bumble bees found in the state.
Cranberries are one crop that require insect pollination to produce fruit. The majority of Wisconsin cranberry growers rent 2-5 hives of honey bees per acre to meet these pollination requirements, costing them tens of thousands of dollars each year. In order for growers to manage their property to support more native bees, we first need to understand what habitats and resources native bees are responding to in the landscape.