Institute of Ag Professionals Proceedings of the 2008 Crop Pest Management Shortcourse & Minnesota Crop Production Retailers Association Trade Show www.extension.umn.edu/agprofessionals Do not reproduce or redistribute without the written consent of author(s).
Honey Bee Protection and Insecticides Marla Spivak University of Minnesota www.extension.umn.edu/honeybees
Large Colony Small Colony
Apiaries
Healthy Honey Bees
Division of Labor in a Honey Bee Colony Honey 15-21 days old - receive nectar - build comb - Hygienic behavior 1-14 d old nurse bees Queen & Brood 3-6 weeks old - pollen & nectar foragers - defenders
Collecting Pollen and Nectar
Umberto Moreno
Variety of pollens with different protein contents Michael Traynor
Pesticide class and types of compounds detected in 108 pollen samples in 2007 Frazier et al 2008. Amer Bee J.
Most frequently detected pesticides in pollen of honey bees
Most frequently detected pesticides in brood nest wax of honey bees
Beekeepers apply pesticides to control parasitic mites on bees Fluvalinate (pyrethroid): 1986-1998 Coumaphos (organophosphate): 1999-2005
Life Cycle of Varroa destructor on Apis mellifera
Impact of Varroa destructor on Apis mellifera: Reduces body weight and longevity Suppresses immune system Vectors bee viruses De Jong et al., 1982, Schneider and Drescher, 1987; Yang and Cox-Foster, 2005
Neonicotinoid systemic insecticide Neurotoxin: binds to and stimulates nicotinic acetylcholine receptors
Neonicotinoids Chemical Brand Names Current Uses imidacloprid thiamoxetham acetamiprid clothianidin Confidor, Merit, Admire, Legend, Provado, Encore, Gaucho, Premise Actara, Platinum, Helix, Cruiser, Adage, Meridian, Centric, Flagship Pristine, Tristar, Assail, Intruder, Adjust Poncho, Titan, Clutch, Belay, Arena blueberries, citrus, cranberries, strawberries, pecans, stone fruits, cotton, corn, melons, vegetables, forestry, ornamentals, turf, and others apple, pecan, stone fruits, melons, peppers, cotton, corn, and others grapes, citrus, canola (seed treatment) citrus, pone fruits, leafy vegetables, ornamentals, and others corn (seed treatment) and canola (seed treatment) with others pending thiacloprid Calypso apples, pears, cotton, and others dinotefuran Dinotefuran none - some pending
Neonicotinoids Toxicity to Honeybees Chemical Acute Contact LD 50 (μg ai/bee) thiamethoxam 0.024 highly toxic clothianidin 0.0439 highly toxic imidacloprid 0.078 highly toxic acetamiprid 8.1 moderately toxic thiacloprid 17.32 practically nontoxic Acute Oral LD 50 (μg ai/bee) 0.005 highly toxic 0.0037 highly toxic 0.0039 highly toxic 15.1 slightly toxic 17.32 slightly toxic
Foraging trip of a weakened bee in our modern landscape:
http://www.art.com/ It used to be if fruit orchard or farm needed bees for pollination, a beekeeper brought in a few colonies for a handshake
Almonds In 2006, over 550,000 acres of almonds in bloom at 2 colonies / acre, growers rented 1.2 million colonies of honey bees In 2010, 750,000 acres will be in bloom almond growers will need more than half of all the commercial honey bee colonies in the US
Simple Beekeeping Economics Current price of honey (wholesale) = $1.20/lb Beekeeper with 2,000 colonies, producing 75 lbs/ colony can gross $180,000 Current price for renting colony for almond pollination = $150/colony Beekeeper with 2000 colonies can gross $300,000 during winter
Recipe for Disaster: 1. Resistant Varroa mites 2. Reduced forage and DIVERSITY of forage 3. Poor bee nutrition 4. Crop and urban pesticides 5. Depressed honey market 6. Increased acreage of almonds, blueberries, cranberries, pumpkins, etc etc etc 7. $$ in pollination contracts 8. Increased movement of bees Mix well and add. New pathogens, new pesticides.
What are the symptoms of Colony Collapse Disorder (CCD)? Healthy colony CCD colony
Varroa Viruses In-Hive Pesticides Nosema Environmental Pesticides Nutrition
What can the public do? Plant flowers! www.xerces.org/poll inator-conservation/ Pay attention to neonicotinoid systemic insecticide use, especially in urban landscapes! Plant bee gardens Encourage roadside plantings of flowers CRP land: put legumes in mix
What can pesticide applicators do? Protect bees from Pesticides Blossoms Bees! Blue orchard bee Honey bee Bumble bee
Honey Plants Clover Alfalfa Basswood Bee Flowers weeds Mustards Birdsfoot trefoil Thistles Dandelion Purple loosestrife Gardens/ fruit trees Vine crops Berries Etc. etc etc
Bees collect corn pollen but only when hungry (low protein content) Bees collect nectar from soybeans in MN only when hot and humid
Bees forage 2.5 miles from colony, on average
Intended Foraging Range for Crop Pollination
Foraging range If the crop is less attractive to honey bees than clover, alfalfa, and other wildflowers
# of foragers Number of foragers vs. Time of day Bees forage sun up to sun down, unless it s raining Sun up Time of Day Sun down
# of foragers Spray Times Sun down to sun up, unless it s raining OK if no residue Kills Bees Best OK if little residue Sun up Time of Day Sun down
Pesticide Kills Foragers can be killed from direct application or residue
Pesticide Kills High mortality in front of colonies is usually due to pesticides
Some pesticides carried back with pollen (or as dust) and stored in hives. Residue kills bees in colony later on (Penncap, Sevin)
Communication and Cooperation Look for apiaries, inquire within 2 mile radius Watch for honeybees on blossoms Notify beekeepers 2-3 days prior to application Consider alternatives (IPM and bee toxicity)
Reducing bee kill Choose pesticides with LOW toxicity and LOW residue Do not spray on blooming plants while bees are foraging Do not allow spray to drift on blooming plants It is best to spray in evening or early morning
Toxicity Most organophosphate and carbamate insecticides are highly toxic to bees Pyrethroids tend to be less harmful in the field due in part to shorter residual effect and repellency Neonicotinoid toxicity being studied intensively
Restricted Entry Intervals - REI The shorter the REI, the better for bees Ambush, Asana, Pounce (pyrethroids) Furadan, Lannate (carbamates) Penncap-M (OP) Lorsban (OP) 12 h 48 h 4 days 24 h
Toxicity Unusually low temperatures at time of application may cause insecticides to remain toxic up to 20 times longer than during warm weather. Cloud cover also may increase residual activity due to lower levels of ultraviolet light which breaks down many pesticides.
Honey Bee Toxicity Groups and Cautions Toxicity Group I Product contains any active ingredient with acute LD50 of 2 micrograms/bee or less. Precautionary Statement if Extended Residual Toxicity is Displayed This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area. Precautionary Statement of Extended Residual Toxicity is not Displayed This product is highly toxic to bees exposed to direct treatment on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds while bees are actively visiting the treatment area.
Honey Bee Toxicity Groups and Cautions in Plain Language Toxicity Group I HIGHLY TOXIC Precautionary Statement if Extended Residual Toxicity is Displayed Do not apply this product or allow it to drift on blooming crops or weeds if bees are or will be foraging in the treatment area. Precautionary Statement of Extended Residual Toxicity is not Displayed Apply only in evening or early morning when bees are not actively foraging in the treatment area or the drift zone.
Honey Bee Toxicity Groups and Cautions Toxicity Group II Product contains any active ingredient(s) with acute LD50 of greater than 2 micrograms/bee but less than 11 micrograms/bee. III All others. Precautionary Statement if Extended Residual Toxicity is Displayed This product is toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product if bees are visiting the treatment area. No bee caution required. Precautionary Statement of Extended Residual Toxicity is not Displayed This product is toxic to bees exposed to direct treatment. Do not apply this product while bees are actively visiting the treatment area. No bee caution required.
# of foragers Spray Times Sun down to sun up, unless it s raining OK if no residue Kills Bees Best OK if little residue Sun up Time of Day Sun down
Neonicotinoids Toxicity to Honeybees Chemical Acute Contact LD 50 (μg ai/bee) thiamethoxam 0.024 highly toxic clothianidin 0.0439 highly toxic imidacloprid 0.078 highly toxic acetamiprid 8.1 moderately toxic thiacloprid 17.32 practically nontoxic Acute Oral LD 50 (μg ai/bee) 0.005 highly toxic 0.0037 highly toxic 0.0039 highly toxic 15.1 slightly toxic 17.32 slightly toxic
www.extension.umn.edu/honeybees