chapter  8
Farm-tailored measures to sustain and enhance pollination services
ByRufus Isaacs, Brett Blaauw, Neal Williams, Peter Kwapong, Eric Lee-Mäder, Mace Vaughan
Pages 18

In many parts of the world, crops that require pollination by bees are managed using honey bee hives brought directly to the crop fields. Renting these colonies from beekeepers is common in regions with intensive production of fruit, vegetable, oilseed and nut crops (Delaplane and Mayer 2000), but a significant proportion of global crop production has limited availability of honey bee hives for rental. While these colonies provide large numbers of foraging bees, with flexibility for use where and when they are needed, honey bees may not be the most efficient pollinators of flowers for many of these crops. In these situations, exploration of alternative approaches to support crop pollination requirements has led to the development of other managed bee species, such as bumble bees or solitary Osmia bees that can complement or in some cases replace honey bees (James and Pitts-Singer 2008). In addition to these managed bees, a significant amount of crop pollination can be delivered by some of the approximately 20,000 species of wild bees that have been described. Their contribution can range from partial delivery of the required pollen needs (Isaacs and Kirk 2010; Rogers et al. 2014) to meeting the complete pollination needs of the crop (Winfree et al. 2008), as well as enhancing the pollination provided by honey bees (Greenleaf and Kremen 2006; Brittain et al. 2013a). Overall, their pollination services can provide insurance against the potential loss of honey bees (Winfree et al. 2007). The degree to which these bees contribute to the pollination needs of crops depends on bee population levels and distribution, which are driven by nesting and foraging resources at local and landscape scales (Holzschuh et al. 2012; Kennedy et al. 2013) and by the pollination biology of the bee-crop interactions (Garibaldi et al. 2014). This chapter addresses the factors that farm managers can control to support wild pollinators, and highlights habitat manipulation in particular. We then provide specific examples of

crop systems where such approaches are being developed, are being tested, or are being implemented. As this is currently a developing field, we also discuss some of the challenges that need to be overcome to increase the success and adoption of farm-tailored approaches to pollinator conservation.