Pollinators: Who are the players and what can we do to protect them?

Christelle Guédot Department of Entomology

•Transfer of grains from anthers (male parts) to stigma (female parts)

•Self-pollination: transfer within a flower or flowers of same plant

•Cross-pollination: transfer between plants Why is pollination important?

1. Ecological ~80% of flowering plants rely on for gene transfer (seed and pollen). Fruits and seeds comprise ~25% of diets of birds and mammals; so lack pollination means scarce resources 2. Agricultural pollinate ~2/3 of world’s crops account for 1/3 of food we eat

3. Economics of pollination ~$15 billion per year to the US economy $217 billion worldwide (Science Daily 2008)

GardenSouth Major insect pollinators

> 70% flowering plants (~250,000 spp.) require an insect to move pollen Most important insect pollinators: Bees

1. Feed on and pollen 2. Pollen collecting structures (scopa, corbicula) 3. Display floral constancy Osmia bicornis

Andrena

Jeremy Early

Wikimedia Commons

John B. Pascarella, Sam Houston State University

http://www.natures- desktop.com/images/wallpapers/1600x1200/i nsects/bee-collecting-pollen.jpg pollinator.info Directed pollen transfer

Pollen ‘sticks’ to pollinator, Pumpkin pollen facilitated by pollen grain morphology Bees pack pollen on pollen basket during grooming Passive movement (i.e., unintentional) between flowers John Kimbler Electrostatic charge aids in pollen transfer Pollen flow commonly skewed towards short distances (i.e., a few meters), but can be substantial (African fig tree- system max = 160 km!) Why are bees important?

Whole foods and Xerces Society "Share the Buzz" campaign (2013) Bees

• At least 20,000 known species of bees (more than birds and mammals combined!) • Social vs. solitary, 90% being solitary • ~4,500 solitary spp. in North America

Stephen Buchmann • Wisconsin: ~400 spp. Smallest North American bee (Perdita minima) on largest female carpenter bee

Native Exotic

T'ai Roulston, University of Virginia The honeybee

Honeybees account for 45% of crop pollination

• 7 species of honeybees • Western honeybee, Apis mellifera only species in North America • Non-native, introduced in 1600s http://www.hdwallpapersinn.com/honey-bee-wallpapers.html • Social colonies founded by single queen • Colonies are perennial • Hive with typically 30 to 50,000 workers Bumblebees

All bumble species in genus Bombus, meaning “booming” • 250 known species (probably most discovered) • 49 species in U.S. • Social colonies founded by single queen (only queen overwinters) • Most abundant native pollinators of both crops and wild flowers

James Nieh/UCSD Steve Javorek (AgCanada) Eric Mader, Elaine Evans Solitary bees

Polyester bee (Colletes sp) Leafcutter bee (Megachile sp.)

Photos: James Cane; Steve Javorek (Ag Canada); Edward S. Ross Solitary bees

Metallic sweat bee (Agapostemon sp.) Yellow-faced bee (Hylaeus sp.)

Mason bee (Osmia sp.) Sweat bee (Halictus sp.)

Photos: Bruce Newhouse; Edward S. Ross; Mace Vaughan; USDA-ARS/Jack Dykinga Solitary bees

Sunflower bee (Svastra sp.) Carpenter bee (Xylocopa sp.)

Photo: Bob Hammond, CSU Coop Ext

Long-horned bee (Mellisodes sp.)

Photo: Bob Hammond, CSU Coop Ext Life Cycle of a Solitary Bee

Mining bee (Andrena sp.): a year in its underground nest as egg, , and before emerging to spend a few weeks as an adult.

Photos: Dennis Briggs The Xerces Society Activity periods of bees

May et al. 2015 MSU Extension Bulletin E3245 Ground-nesting solitary bees

Most (70%) nest underground

Photos: Eric Mader, Matthew Shepherd, Dennis Briggs Cavity-nesting solitary bees

Other 30% nest in pre-existing cavities • Nest in hollow plant stems, old beetle borer holes, man-made cavities • Artificially managed for some crops

Jim Cane Stephen Buchmann

Photos: Edward Ross, Darrin O’Brien, Matthew Shepherd Cavity-nesting solitary bees

Blue orchard bee • Native pollinator • Great pollinator of orchard trees (almond, , cherry, apricot,…) • Used in commercial pollination

Photo: Eric Mader Pollinator protection and conservation Pollinator decline

Colony collapse disorder: Honeybees

In 2006, U.S. beekeepers reported losses of 30-90% of hives

Main symptoms: very low or no worker bees, queen is alive, with larvae present, and no dead bodies inside or in front of hive (thus hard to study potential causes…) Honeybees

Currently, estimated 2.62 million colonies of honeybees in USA Pollinator decline

Factors associated with honeybee declines:

• pests and pathogens • Poor nutrition • Bee management practices • Agricultural practices and pesticides • Habitat fragmentation

Not a single factor, but a combination of factors Pests and pathogens

Since 1984, multiple introduction of invasive species: • parasitic tracheal mite Acarapis woodi (identified 1984) • parasitic mite Varroa destructor (identified 1987) • Africanized honey bees (1991) • small hive beetle Aethina tumida (identified 1996) • Israeli Acute Paralysis Virus - IAPV (identified 2007) • gut parasite Nosema ceranae (identified 2007)

USDA CCD 2012 Annual Progress Report Pests and pathogens

Parasitic mite: Varroa destructor • Single most detrimental pest of honeybees • Introduced from Eastern Asia and identified in U.S. hives in 1987 • Blood sucking parasites that also transmit viruses to bees • Cause significant colony losses each year

Varroa destructor

http://www.ibra.org.uk/articles/20080609_5

Photo: USDA-ARS/Scott Bauer Poor nutrition

Monoculture, i.e. almond and other commercial crops provide no diversity of food Bee management practices

Not uncommon for beekeeper to travel 37,000-40,000 miles per year to pollinate 4 or more different crop

Nicholas Calderone

http://www.personcountybeekeepers.org

Rucker et al 2001 Pesticide exposure

Pesticides: insecticides, fungicides, and herbicides (and adjuvants)

2013 Regents of the University of California Pesticide exposure

How do pesticides affect pollinators • Lethal effects: acutely toxic to bees and result in death • Sublethal effects: do not kill bees but affect performance that inhibit tasks such as olfactory learning, foraging, reproduction, longevity,…thus affecting colony health • Synergistic effects: toxic effects when in combination with other pesticides

http://www.pollinator.ca/ Pesticide exposure

List of pesticides found in pollen on honeybees returning to hive

Fungicides Herbicides Insecticides

Pettis et al 2013 PlosOne 8: 1-9 Pesticide exposure

Imidacloprid registered in 1994

http://water.usgs.gov/nawqa/pnsp/usage/maps/show_map.php?year=1993&map=IMIDACLOPRID&hilo=L Pesticide exposure

Organic-approved pesticides not necessarily safe for bees • Pyrethrins = Dangerous for Bees! • Spinosad = Dangerous for Bees! • Beauveria bassiana = Dangerous!

Okay when not directly applied to bees (i.e. non-blooming crops or at night): • Insecticidal soap • Horticultural oil • Neem

Reduce Bee Poisoning from Pesticides Oregon State University https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/pnw591.pdf Pollinator habitat

• Loss of suitable habitat • Fragmentation into smaller isolated habitat patches

Rusty patched bumble bee Yellow banded bumble bee Bombus affinis Bombus terricola Pollinator conservation and protection

Russ James http://www.xerces.org/wp-content/uploads/2014/09/MidwestPlantList_web.pdf Pollinator conservation: Provide resources

• Provide a variety of pollen/nectar sources • Provide season long forage (min. 3 per season)

Hyatt Regency Atlanta

Getty Images: Dan Kitwood Photos: Matthew Shepherd (Xerces Society) Plants for Midwest

Native flowers • Blazing star • Lupine • Goldenrod • Spiderwort • Asters • Penstemon • Prairie clover • Milkweed • Purple cone flower • Beebalm • Leadplant • Joe Pye weed • Cup plant

The Xerces Society Photos: Eric Mader Plants for Midwest

Woody plants • Redbud • Apple • Plum • Basswood • Wild rose • Pussy willow • Hawthorn • Ninebark • Raspberry • Blueberry

The Xerces Society Pollinator conservation: Prevent diseases

• Avoid locating honey bees near conservation areas

• Diseases can be spread through pollen Pollinator conservation: Pesticide protection

• Pesticides not tested on native pollinators

• Use the lowest risk/lowest concentration

• Avoid dusts and micro-encapsulated products

• Avoid products with long residual (systemic)

• Time applications to avoid bees

• Spray in the evening when bees not active Pollinator conservation: bee-friendly farming

Protect ground nests: • Reduce Tillage • Avoid soil fumigants • Minimize plastic mulch

Photo: USDA-ARS Pollinator conservation: Provide nesting habitat

Provide bare soil for ground nesters

• Cut/burn limited areas

• Retain bare land/untilled areas

• Clear away some plants from well drained slopes

• Use cover crops that serve as forage Pollinator conservation: Provide nesting habitat

Provide cavities for cavity nesters: • Prefer wood • Provide artificial nesting holes

Russ James

http://www.kinsmangarden.com / Wisconsin Fruit News Wisconsin Fruit website http://fruit.wisc.edu Questions?

Christelle Guédot [email protected] (608) 262-0899