In order for society to be able to capitalize upon the value of bees in pollination and environmental monitoring, a variety of solutions to the taxonomic impediment will be required. Bees are essential components of almost all of the world’s terrestrial ecosystems. They provide both pollination services, and are excellent indicators of the state of terrestrial environments including responses to global warming. A major challenge to knowing how to manage wild bees for pollination services, or to using their occurrence as an indicator of ecosystem health is the taxonomic impediment to identifying the exact name of a pollinator. Knowing the taxonomy of a bee assists in knowing many aspects of its ecology and natural history – where it nests, for instance, and how it may be affected by climate. Bee experts are too few to provide identification services all around the world. Furthermore, a beginner trying to identify bees faces immense obstacles. Yet this taxonomic impediment is not insurmountable.

Pollinator management at different levels

Biodiversity in agricultural landscapes can provide important pollination services, and serve as a critical form of insurance against the risks of pests and diseases amongst managed pollinators. Specific practices that farmers can undertake to promote pollinators on their farms, however, are less well understood or appreciated. FAO, working with experts, has carried out an initial survey of existing good practices to conserve and manage wild pollination services, upon which new practices can be based.  Farmers can introduce measures to promote pollinators at a variety of different scales. Most commonly, farmers can make modifications to how they apply farming practices in their fields that will benefit pollinators.  But there are other scales of management that are also important, from practices on non-farmed land and field edges, to management of agricultural landscapes.

Field scale

At the field scale, pollinator-friendly practices include minimizing the use of farm chemicals, through organic production, integrated pest management, or finding alternatives to agrochemicals. A reduction in the use of herbicides, as well as pesticides, is recognised as having benefits for keeping pollinators in the crop fields. One innovative mango farmer in Ghana switched to clearing the weeds manually instead of chemically, despite a seven-fold increase in costs. Herbicides killed the weeds to their roots, whereas they were quick to regenerate with the rains when cut by machete; by allowing the weeds to selectively flourish when the mangos were in bloom, he could attract more pollinators into his fields and boost fruit yields. Cardamom farmers in the Western Ghats in India are learning to subtly manipulate shade-tree cultivation in their fields to ensure continuity of pollinators. Because cardamom requires pollinators for fruit production it is crucial to ensure that large numbers of pollinators are available during the blooming season. Most pollinators of cardamom are wild and thus move freely through the landscape. Because cardamom does not bloom year round, pollinators may leave cardamom plantations once blooming finishes and they do not necessarily return the following season. Many cardamom farmers also cultivate coffee, with an even shorter mass blooming season. Farmers are beginning to plant a diversity of flowering tree species (called “sequential blooms”) that provide reliable pollen and nectar resources for valuable native bees at times of the years when neither cardamom nor coffee is blooming. For example, farmers may use two species of Schefflera whose flowers are attractive to bees. Both flower almost immediately after coffee finishes blooming in the region and just before cardamom begins – thus greatly reducing the number of bees that leave plantations during the off-season.

Farm scale

The way farmers organise different land uses across their farms can influence pollination services. In Colombia, farmers recognised that they encouraged pollinator populations by conserving diverse cropping patterns in their farms, for example by combining mixed cropping, kitchen gardens and agroforestry systems, and providing habitat on their farms for bees. Similarly, farmers in Tanzania understood and encouraged the nesting of carpenter bees in their houses, despite some minor structural damage.

Landscape scale

Farmers from many regions recognised that they benefited from areas of natural vegetation in close proximity to farmland. Such habitat patches provided flowering resources and nesting sites that sustain pollinators. Pollinator resources – such as Acacia trees – often had multiple benefits for farmers, providing not just food for pollinators but tradable commodities or livestock feed at critical points, or sources of traditional medicines. In Colombia, farmers recognised the importance of maintaining biological corridors across the landscape for native flora and fauna. Practical applications of good practices in on-the-ground settings are informative for people learning to better manage pollination services. Evaluation of good practices for their impacts on pollinators, and their relative costs and benefits to farmers and land managers is also useful, since the value of these practices must withstand the test of providing sufficient benefits, considering the time, effort and costs of implementing them.

In multiple agro-ecosystems and ecologies, pollinator-friendly management practices have been identified that serve to enhance yields, quality, diversity and resilience of cropping systems:

• Preserving wild habitat.
• Managing cropping systems, flower-rich field margins, buffer zones and permanent hedgerows to ensure habitat and forage.
• Cultivating shade trees.
• Managing for bee nest sites, e.g. by leaving standing dead trees and fallen branches undisturbed. 
• Reducing application of pesticides and associated risks.
• Establishing landscape configurations that favour pollination services
   
   

Pollination Information Management System (PIMS)

The Pollination Information Management System, (PIMS) is being developed through collaboration between FAO and a number of national level organizations concerned with the conservation and sustainable use of pollination services for sustainable agriculture. The PIMS serves to organize and deliver accurate information on managing pollination services of key crops, globally, to farmers, farm advisors and land managers. The system is designed to help users to answer the following questions:

• What are the pollination needs of a particular crop?
• What is the current understanding of managing the pollination of a particular crop?
• What studies have been carried out on the pollination of this crop? 
• What is known about the pollinators of this crop?

Determining the need for insect pollination

There are a number of ways to find whether a particular crop benefits from insect pollination. It is impossible to keep pollinating insects away from an area of crops without caging it, and the most common procedure is to enclose parts of the crop in insect-proof screen cages which should be as large as practical, and put honeybee colonies in some but not others. Other plots, of the same area as that covered by a cage, are left exposed. Hence comparison is made of the three treatments: (a) caged with bees; (b) caged without bees; (c) not caged and visited by pollinating insects including honeybees from nearby colonies. Sometimes insecticide is applied to plots caged without bees to eliminate all pollinating insects. Ideally both the caged plots with and without bees should be treated with insecticide if the effect of the bees alone is being determined, but this often entails confining the bees to their colonies for a day or so, with a consequent loss in pollinating efficiency. Sometimes additional screen cages are used with a mesh size that excludes large insects, such as bees, but not small ones from entering; however, it is difficult to know precisely what effect the use of cages with different size mesh does have on the insect population and on any pollination by wind. The cages themselves cannot reproduce field conditions inside because of differences in temperature, humidity, shading, air movement and attack by pests, and often have an adverse effect on plant yield especially in warm climates. Attempts are sometimes made to determine the effects of shading and reducing wind inside cages by using cages without tops or without sides, but as these treatments probably also reduce bee visits, it is again difficult to evaluate the results obtained. Attempts that have been made to prevent wind and insect pollination by covering the cages of control plots with clear plastic sheets must alter the environment inside greatly.

Dealing with climate change

Pollination management practices can also be applied to mitigate climate change. Many good farming practices that sustain the ability of agroecosystems to deliver ecosystem services involve measures to increase ground cover and crop-associated biodiversity. Hence, measures to promote pollinators include providing more non-crop flowering resources in fields, such as cover crops, strip crops or hedgerows.

1. Promote policies that support pollination-friendly actions such as land use planning and, as applicable, responsible use of pesticides.
2. Build capacity for sustainably managing pollinators.
3. Raise awareness of the contribution of pollination to sustainable agriculture and livelihoods.

Adaptation

Ecosystem services build important measures of resilience and risk mitigation into agriculture – elements that are increasingly important under changing climates. The greater number and kinds of facilitative interactions in an ecosystem – any ecosystem, but even more so in a simplified farming system – means that as conditions change, there are different groups of organisms that are favoured to continue providing ecosystem services. Farming communities may best adapt to climate change impacts on pollinators by:

• Giving consideration to the season long resources needed by pollinators, both before and after crop flowering (often provided by wild or semi wild areas of habitat in agricultural landscapes)
• Ensuring connectivity of natural habitats in farming areas, so that pollinators can more easily disperse and make needed range shifts in response to changing climates.

 

Mitigation

Measures to promote beneficial insects that help to reduce crop pests, similarly to measures to promote pollinators, include providing more non-crop flowering resources in fields, such as cover crops, strip crops or hedgerows. Many possible mitigation measures, taken together, contribute to the long-term stability of agroecosystems by helping to provide greater and more continuous biomass cover on-farm. These same practices, retaining large quantities of biomass and soil organic matter, may serve to enhance the ability of agricultural systems to sequester carbon.  Farmers and farming communities have the potential to undertake measures that can conserve and strengthen linkages between different aspects of agrobiodiversity, and contribute to long-term stability in the face of climate change.