The effects of protein supplementation, fumagillin treatment, and colony management on the productivity and long-term survival of honey bee (Apis mellifera) colonies.

In this study, we intensively measured the longitudinal productivity and survival of 362 commercially managed honey bee colonies in Canada, over a two-year period. A full factorial experimental design was used, whereby two treatments were repeated across apiaries situated in three distinct geographic regions: Northern Alberta, Southern Alberta and Prince Edward Island, each having unique bee management strategies. In the protein supplemented treatment, colonies were continuously provided a commercial protein supplement containing 25% w/w pollen, in addition to any feed normally provided by beekeepers in that region. In the fumagillin treatment, colonies were treated with the label dose of Fumagilin-B® each year during the fall. Neither treatment provided consistent benefits across all sites and dates. Fumagillin was associated with a large increase in honey production only at the Northern Alberta site, while protein supplementation produced an early season increase in brood production only at the Southern Alberta site. The protein supplement provided no long-lasting benefit at any site and was also associated with an increased risk of death and decreased colony size later in the study. Differences in colony survival and productivity among regions, and among colonies within beekeeping operations, were far larger than the effects of either treatment, suggesting that returns from extra feed supplements and fumagillin were highly contextually dependent. We conclude that use of fumagillin is safe and sometimes beneficial, but that beekeepers should only consider excess protein supplementation when natural forage is limiting.

Effect of Fumagilin-B treatment timing on nosema (Vairimorpha spp.; Microspora: Nosematidae) abundance and honey bee (Hymenoptera: Apidae) colonies under winter management in the Canadian Prairies.

Fumagilin-B is used to treat nosema infection in honey bee colonies; however, it is unclear whether treatment consistently reduces Vairimorpha ceranae (Fries et al.) abundance and improves colony strength and survival in the Canadian Prairies. This study assessed spring and fall fumagillin treatments on nosema abundance, colony strength, and mortality in 2 different beekeeping regions within Alberta, using both indoor and outdoor wintering management at each site. We compared 4 fumagillin treatments: Spring-only, Fall-only, Spring-and-Fall, and Control (no treatment). The spring treatment dose was ~68 mg/colony, whereas the fall treatment dose was 120 or 48 mg/colony, depending on the year. We found that the colonies were infected predominately with V. ceranae, with V. apis (Zander) present only in mixed infections in a subset of colonies. Although treatment in either the spring or fall did reduce nosema abundance in the short term, it did not eliminate the infection, making continued monitoring necessary. Colony strength was improved by spring treatment in some locations but not consistently, possibly due to the treatment timing or low dose. The combined spring and fall treatment increased colony survival over winter in one of 2 yr. Wintering method did not interact with treatment to affect nosema abundance in the spring. There does not appear to be a significant residual benefit of fall treatment as it did not reduce spring nosema abundance or increase colony population. Therefore, spring treatment should be applied to reduce spring V. ceranae abundance rather than relying on residual efficacy from previous fall treatments.

Consumption of Supplemental Spring Protein Feeds by Western Honey Bee (Hymenoptera: Apidae) Colonies: Effects on Colony Growth and Pollination Potential.

Adequate nutrition is required to support productive honey bee colonies, therefore beekeepers supplement colonies with additional protein at targeted time points. We tested the effects of commercially available protein feeds in spring, in advance of colonies being used for hybrid canola pollination. The feed treatments across the three-year study included the following patty types: Global 15% pollen, Global 0% pollen, Bee Pollen-Ate, FeedBee, and Healthy Bees, as well as an unsupplemented control in year two of the study only. The amount of feed consumed varied among colonies, treatments, date, and year. Similarly, there were also differences in feed efficiency (bees reared per gram of feed consumed), likely due to the relative availability of external forage sources to supplement the feed provided. Unsupplemented colonies were able to rear less brood, and subsequently had fewer adult bees than supplemented colonies, in an apiary where pollen was not abundant. Differences in consumption among treatments often failed to translate in to differences in amount of brood reared or subsequent adult population. All the protein feed treatments contained all ten amino acids essential to honey bees, however lysine and arginine were below the optimal proportion required for growth in all patties except the FeedBee patty. The amount of protein and amount and types of sugars and fats in the products also varied among product type and batch. The results of this study demonstrate a benefit to supplementary spring protein feeding to increase honey bee colony populations in advance of a summer pollination market.

Comparison of Honey Bee (Hymenoptera: Apidae) Colony Units of Different Sizes as Pollinators of Hybrid Seed Canola.

We compare two different sizes of honey bee colony units: singles (one brood chamber) and doubles (two brood chambers) in hybrid seed canola pollination in southern Alberta in 2014 and 2015. Currently, canola seed production companies only contract double-brood chamber units to pollinate canola in southern Alberta, but it may be advantageous to the industry if singles could also be contracted for pollination, as they are in many other crops. To evaluate the differences between the colony units, we measured population size, nectar and pollen foraging, nectar and pollen load weights, pollen collection, and honey production. The colony populations of both the single- and double-brood chamber hives in this study were highly variable. In 2015, there was no difference between the single- and the double-brood chamber colonies in adult bee populations, and the singles had more sealed brood than did the double-brood chamber colonies. Our findings indicate that in comparison to doubles, on a per-frame basis, singles yield more pollen, more nectar foragers, similar or more pollen foragers, and similar amounts of honey. Therefore, we conclude that singles could be used to provide the same level of pollination services as doubles currently do in hybrid seed canola pollination, and growers should focus on receiving healthy populous colonies, regardless of the number of brood boxes.

Pollen Collection, Honey Production, and Pollination Services: Managing Honey Bees in an Agricultural Setting.

Hybrid canola seed production is an important pollination market in Canada; typically both honey bees (Apis mellifera L. (Hymenoptera: Apidae)) and Alfalfa Leafcutting bees (Megachile rotundata Fab. (Hymenoptera: Megachilidae)) are concurrently managed to ensure pollination in this high-value crop. Beekeepers are paid to provide pollination services, and the colonies also produce a honey crop from the canola. Pollen availability from male-fertile plants is carefully managed in this crop to provide an abundance of pollen to fertilize male-sterile ('female') plants. This abundance of pollen represents an underutilized resource for beekeepers, and an opportunity to diversify the hive-products produced for market in this management system. We used a commercial-style pollen trap to collect pollen from colonies twice weekly for the duration of canola pollination, and compared the honey production and amount of sealed brood in colonies with pollen traps to those without pollen traps. We found that while pollen trapping reduced honey production, there was no negative impact on brood production, and at current market prices, the per-hive revenue was higher in colonies from which pollen was trapped. Pollen trapping honey bee colonies in the context of hybrid canola pollination, therefore, offers beekeepers an opportunity to diversify their products and increase their revenue.