Rationale for action
Pollination is critical to human agriculture and native ecosystems alike, with an estimated 35% of the world's flowering plants depending on animals-most of them insects-for pollination. Animal pollinators in the north temperate zone include bees, butterflies, moths, wasps, flies, beetles, ants, and bats. Insects make up the vast majority of pollinator species, and bees are the most important pollinators. About 17000 species of bee have been identified; who knows how many more are yet to be discerned? There are about 4500 kinds of wild bee in North America. In Britain it has been estimated that there are about 250 wild bees, most of which are solitary insects. Many of them share our gardens with us, and about a quarter of them are considered rare or endangered. Gardens are very important for their conservation.
Although the European honey bee is the best-known crop pollinator, research shows that native bees contribute substantially to the pollination of many crops. In addition, native bees provide incalculable value as pollinators of native plants. Wild bees are defined as all of the members of the superfamily Apoidea (bees) other than the genus Apis (honey bees). Most efforts to improve crop pollination have been made with the honey bee (Apis mellifera) which is the principal pollinator of most insect-pollinated crops. Management of wild bees has been tried only for crops which, under at least some circumstances, are poorly or inefficiently pollinated by honey bees. Wild bee management has been used for red clover seed, and apples, but principally in the areas where their pollination by the honey bee presents particular problems.
The management of wild bees for crop pollination can be described as a new entomological industry, which in the United States involves well over $1,000,000 per year in terms of expenditures and benefits. It has become an industry with several facets, including the manufacture and sale of equipment, the propagation and sale of bees, pollination on a contract basis, and the propagation and use of bees by seed growers. Amateur bee keepers have been slow to engage with wild bees, but they would seem to be well qualified for the task.
While significant media attention has been devoted in recent years to the decline of honey bees, there is also evidence for the loss of wild pollinators. In some cases the fates of those wild native pollinators are significantly worse than the introduced honey bee. Causes of declines are difficult to pinpoint, but loss of habitat due to increasing urbanization, expansion of intensive agriculture, invasive species, introduced diseases and parasites, and the widespread use of pesticides all negatively impact pollinator populations. Protecting, enhancing, or providing new habitat is the best way to conserve native pollinators.
Environmental Benefits
Ecosystem enhancement
Unlike many of the crucial but often abstract and contentious environmental issues facing us today, the highly publicized decline of honey bees, bumble bees, butterflies, and other iconic flower visitors inspires broad public sympathy and motivates grassroots efforts. By focusing on their needs for habitat, and protection from pesticides, pollinator conservation provides a convenient framework for achieving multiple goals.
Frequently, habitat enhancements for pollinators can provide numerous other environmental benefits. Most obviously, flower-rich native plant landscapes support greater biodiversity, supporting not only pollinators, but also other beneficial insects (including those that prey upon pests), songbirds, and small mammals. Pollinator enhancements can also be integrated into engineered greenspaces.
Links between Rural and Urban Communities
Natural habitat on or close to farms and gardens has a direct influence on pollinator diversity and abundance. Incorporating pollinator habitat in urban areas increases the resiliency of local food systems and connects urban and rural communities through shared interests. Urban gardeners can be encouraged to incorporate pollinator friendly plants in their gardens to provide corridors deep into urban territory.
Practices aimed at restoring natural habitat near farm landscapes not only provide conservation benefits, but also increase growers's security by helping them take full advantage of the crop-pollinating native bees and other beneficial insects. Working with landowners to modify land management practices, such as the timing and intensity of mowing, can also positively impact pollinators. This tangible link between restoring habitat for pollinators and improving crop production helps farmers, park managers, and all citizens understand the importance of natural areas; thus increasing their willingness to support the protection and restoration of these habitats.
Landscape Aesthetics
High-quality pollinator habitat by definition consists of diverse flowering plants that bloom throughout the entire growing season. Studies have linked the availability and quality of public greenspaces to neighbourhood crime reduction, increased property value, and urban livability. Attractive greenspaces increase local residents' sense of place and investment in public spaces, facilitates a strong connection to their community and a willingness to protect their surroundings.
Pollinator Conservation and Public Spaces
Pollinator conservation and habitat enhancement efforts can often be incorporated into land management plans for publicly owned parks, rights-of-way, and natural areas. Simple measures such as incorporating pollinator-friendly plants, reducing the use of pesticides, and strategically timing maintenance activities such as mowing can all help support local pollinator populations.
City, county, or agency-owned owned brownfield sites, such as abandoned industrial waterfronts, and land awaiting development could be relatively easy to enhance for pollinators with low-cost, non-invasive wildflower seed mixes (e.g., species like California poppy, clarkia. and cosmos). Such mass wildflower seedings can improve aesthetics, and reduce the need for routine mowing to maintain visual standards. Such an approach could save money by reducing maintenance costs.
Recommended actions
1 Natural areas can be managed for diversity and abundance of pollinator-friendly plants, nest sites, and butterfly larval host plants. Land managers can, and indeed should, continue efforts to remove invasive species that reduce overall flowering plant diversity. Although some invasive species provide limited resources for pollinators, they do so at the expense of diverse native plant communities that can supply nectar and pollen for a greater variety of animals over a longer period of time.
2 Incentive programmes and partnerships can be supported and expanded to help the region's landowners to create pollinator-friendly, flower-rich habitats in natural and working landscapes. At multiple levels, cost-share assistance and conservation project grants are available and these incentive programmes are a critical link in creating on-the-ground conservation change.
3 Both urban and rural landowners can be engaged to eliminate, minimize, and/or mitigate the impacts of insecticide use on pollinators.
4 Pollinator habitat connectivity can be created across the urban corridor through backyard habitat, eco-roofs, green streets, school, community, and public gardens, and public parks. By emphasizing connectivity, pollinator populations can move in the landscape and re-colonize areas when disturbance occurs.
5 NGOs can educate urban landowners about the diversify of bees and other pollinators in the region. Those education efforts can be more fully integrated into the important research work already underway in universities and government agencies. This is part of a growing citizen science movement where everyone can provide information about successes and failures.