Managing Bees for Pollination
Honey bees are extremely important for the pollination of crops in Canada. There are over 600,000 colonies of honey bees in Canada and they contribute an estimated $1.3-1.7 billion annually in increased production of fruits and vegetables.
To maximize the potential value from pollination services, the Canadian Honey Council recommends a pollination contract and the following guidelines.
How Many Colonies?
The minimum number of colonies depends on the number of other pollinators present. For apple, blueberry and canola pollination the minimum is 1 colony per acre, with up to 2.5 colonies per acre in high density plantings and 5 colonies per acre where there are no native pollinators.
When to contact the beekeeper?
Contact the beekeeper in fall to discuss spring requirements. Demand for honey bee colonies is high and beekeepers need to know before winter how many hives to prepare for spring pollination. A list of beekeepers who can provide pollination service is available from the provincial associations.
Pollination strength hives contain a minimum of 5 frames of bees and brood with 25-30,000 honey bees. Nucleus colonies are not as efficient as overwintered colonies for pollination. Stronger colonies will forage at lower temperatures than weak colonies.
How to estimate colony strength?
Colony strength can be estimated by counting the number of bees leaving the hive entrance. When the temperature is above 15 degrees C (57 degrees F) and there is no wind, there should be 60 bees per minute leaving the hive.
Rental fee for a strong colony is based on the cost of overwintering bees, feeding, medication, transportation, labour, loss of honey from moving the colony, queen loss during travel and a small percentage is retained as return on investment. The rates for blueberries and apples range from $90-120 per colony for pollination and canola $125-$160 per colony, or higher if there are shortages of honey bee colonies.
When to place hives?
In general it is best to move hives into the pollination field when 20% of the crop is in bloom, although requirements may vary between crops.
Move hives at night to prevent the loss of forager bees left in the field.
Movement of hives to fields or orchards of later blooms should be done only after consultation with the beekeeper. If hives are rotated between locations they should be moved more than 2.4 km and always moved at night to prevent bees returning to their original location.
In orchards it is not necessary to mow the grass except for pest control. The presence of dandelions encourages bees to stay in the orchard and they soon find the highly attractive apple blossom. In some cases, mowing may be beneficial by reducing the chance of poisoning should bees forage on dandelions after a toxic spray was applied.
Provide fresh water if there is no source nearby. Bees will collect water from depressions or wheel ruts which may contain accumulated pesticides. To avoid problems, provide water in a shallow container with a float to prevent bees from drowning. Natural wood (untreated) or styrofoam will support water-collecting bees.
Pre-select the site and mark the drop off points with pallets, doors or old lumber. Hives should be 15-20 cm off the ground.
Grass and weeds shade the entrance and hinder flight. Remove long grass.
Place hives in groups of 4-12, about 200 m apart in all directions. Do not scatter hives individually.
Choose a sunny location, with a south or southeast face . Honey bees forage best when temperature is over 12 degrees C and winds less than 15 km/hr. Shaded hives will not be as active.
In exposed areas place a windbreak on the entrance side of the hive (straw bales work well).
Do not spray insecticide or herbicides while bees are present. Dead bees mean lost income for the beekeeper and lost pollination activity for the grower .
All insecticides can be hazardous to honey bees. Fungicides, herbicides and other agricultural chemicals have varying degrees of toxicity. If spraying is unavoidable, contact the beekeeper before spraying begins. The safest option is to move the colonies from the spray area.
Avoid drift of insecticide into bee yards and adjacent crop or wild plants in bloom.
A contract between the beekeeper and the grower is highly recommended. It provides a written agreement between the beekeeper and the grower and clearly states the responsibility of each party.