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Agroforestry can provide ecosystem services and benefits such as soil erosion control, microclimate modification for yield enhancement, economic diversification, livestock production and well-being, and water quality protection. By adding increased structural and functional diversity in agricultural landscapes, agroforestry practices can also affect ecosystem services provided by insect pollinators. This chapter provides a summary of existing scientific information on how temperate agroforestry systems influence insect pollinators and their pollination services. Our assessment indicates that agroforestry practices can provide three primary benefits for pollinators: (1) providing habitat including foraging resources and nesting or egg-laying sites, (2) enhancing site and landscape connectivity, and (3) mitigating pesticide exposure. In some cases, agroforestry practices may contribute to unintended consequences such as becoming a sink for pollinators, where they may have increased exposure to pesticide residue that can accumulate in agroforestry practices. Through a more comprehensive understanding of the effects of agroforestry practices on pollinators and their key services, we can better design agroforestry systems to provide these benefits in addition to other desired ecosystem services.

Agroforestry can provide ecosystem services and benefits such as soil erosion control, microclimate modification for yield enhancement, economic diversification, livestock production and well-being, and water quality protection. Through increased structural and functional diversity in agricultural landscapes, agroforestry practices can also affect ecosystem services provided by insect pollinators. A literature review was conducted to synthesize information on how temperate agroforestry systems influence insect pollinators and their pollination services with particular focus on the role of trees and shrubs. Our review indicates that agroforestry practices can provide three overarching benefits for pollinators: (1) providing habitat including foraging resources and nesting or egg-laying sites, (2) enhancing site and landscape connectivity, and (3) mitigating pesticide exposure. In some cases, agroforestry practices may contribute to unintended consequences such as becoming a sink for pollinators, where they may have increased exposure to pesticide residue that can accumulate in agroforestry practices. Although there is some scientific evidence suggesting that agroforestry practices can enhance crop pollination and yield, more research needs to be conducted on a variety of crops to verify this ecosystem service. Through a more comprehensive understanding of the effects of agroforestry practices on pollinators and their key services, we can better design agroforestry systems to provide these benefits in addition to other desired ecosystem services.

Our growing human population will be increasingly dependent on bees and other pollinators that provide the essential delivery of pollen to crop flowers during bloom. Within the context of challenges to crop pollinators and crop production, farm managers require strategies that can reliably provide sufficient pollination to ensure maximum economic return from their pollinator-dependent crops. There are unexploited opportunities to increase yields by managing insect pollination, especially for crops that are dependent on insect pollination for fruit set. We introduce the concept of Integrated Crop Pollination as a unifying theme under which various strategies supporting crop pollination can be developed, coordinated, and delivered to growers and their advisors. We emphasize combining tactics that are appropriate for the crop’s dependence on insect-mediated pollination, including the use of wild and managed bee species, and enhancing the farm environment for these insects through directed habitat management and pesticide stewardship. This should be done within the economic constraints of the specific farm situation, and so we highlight the need for flexible strategies that can help growers make economically-based ICP decisions using support tools that consider crop value, yield benefits from adoption of ICP components, and the cost of the practices. Finally, education and technology transfer programs will be essential for helping land managers decide on the most efficient way to apply ICP to their unique situations. Building on experiences in North America and beyond, we aim to provide a broad framework for how crop pollination can help secure future food production and support society’s increasing demand for nutritious diets.

North America has more than 4000 bee species, yet we have little information on the health, distribution, and population trends of most of these species. In the United States, what information is available is distributed across multiple institutions, and efforts to track bee populations are largely uncoordinated on a national scale. An overarching framework for monitoring U.S. native bees could provide a system that is responsive to national needs, resources, and capacities. Five major action areas and priorities for structuring a coordinated effort include: (1) Defining the scope, aims, and cost of a national native bee monitoring program; (2) Improving the national capacity in bee taxonomy and systematics; (3) Gathering and cataloging data that are standardized, accessible, and sustainable; (4) Identifying survey methods and prioritizing taxa to monitor; and (5) Prioritizing geographic areas to be monitored. Here, we detail the needs, challenges, and opportunities associated with developing a multi-layered U.S. national plan for native bee monitoring.

Pollinator conservation and rangelands don’t seem like obvious bedfellows. In this era of sustainability, the connection between pollinator conservation and row crops or pollinator conservation and orchards is obvious. But pollinator conservation and rangelands? The reality is that pollinators are a key component of a healthy rangeland ecosystem. As Kevan stated, pollination is “central to all human beings, livestock, and wildlife.”1 Pollinators are essential for rangeland food production, help with nutrient cycling, and are prey for many birds. In essence, they hold a central position in wildlife food webs. For example, many migratory songbirds require a diet of berries, fruits, and seeds from insect-pollinated plants and pollinator larvae are an important component of the diet of many young birds. Belfrage et al. demonstrated that butterfl y diversity was a good predictor of bird abundance and diversity, apparently due to a shared requirement for a complex plant community.2 Pollinators perform such a range of ecological services in natural ecosystems that they are clearly a keystone group in nearly all terrestrial ecosystems and are necessary for plant reproduction and in forming the basis of an energy-rich food web.3 The relationship between pollinators and rangeland goes both ways. Pollinators are important for rangelands but rangelands are important for pollinators because they can provide habitat. Pollinators in North America include hummingbirds and bats, but insects—mainly bees, butterfl ies, moths, wasps, fl ies, and beetles—make up the vast majority of pollinators. Of these, bees are considered the most important pollinators in temperate North America. There are approximately 4,000 species of native bees in North America, many of which will thrive in the varied conditions offered by rangelands. Shrubland and scrub habitat, in particular, can be very valuable habitat. Surveys of pollinators in different California plant communities show that the chaparral community has the largest diversity of bees per unit area of any ecosystem type. Bee habitat requires two basic components: fl owers on which to forage and nest sites. Many pollinators are adapted to forage on particular plants, so a diverse community of pollinators requires a diverse array of fl owers. This can be easily provided by native grassland comprising a variety of grasses and forbs. Most native bees are solitary-nesting. Around 70% of bee species nest in the ground, excavating shallow tunnels in patches of bare soil, with most of the remaining 30% nesting in cavities in old trees or plant stems. Bumble bees require a small cavity such as an abandoned rodent hole. Ground-nesting bees (both solitary bees and bumble bees) are likely the most important pollinators in grasslands, but fl ies, beetles, and butterfl ies will also be prevalent. Rangeland pollinators have benefi ts that go beyond the boundaries of the range. The role that adjacent natural habitat (including grassland, shrubland, and other rangeland types) plays in providing crop pollination services is increasingly well understood: The value of crop pollination by native, wild bees in the United States is estimated at $3 billion. Proximity to natural or seminatural nonagricultural land is often an important predictor of pollinator diversity in cropland. There is evidence of declines in both managed and wild pollinators. Causes of declines are diffi cult to pinpoint, but loss of habitat due to increasing urbanization, expansion of intensive agriculture, invasive plant species, and the widespread use of pesticides all negatively impact pollinator populations, as do disease and parasites affecting the pollinators themselves. Protection of habitat is one way in which rangelands can be of great signifi cance in protecting and conserving pollinators. Natural habitat is integral to maintaining a long-term population of native pollinators in agricultural landscapes. However, it is important that management of rangelands and other nonarable lands takes into account native pollinators.

The Value of Pollinators and Pollinator Habitat to Rangelands: Connections Among Pollinators, Insects, Plant Communities, Fish, and Wildlife DOI:10.2458/azu_rangelands_v33i3_gilgert

The loss of biodiversity is a trend that is garnering much concern. As organisms have evolved mutualistic and synergistic relationships, the loss of one or a few species can have a much wider environmental impact. Since much pollination is facilitated by bees, the reported colony collapse disorder has many worried of widespread agricultural fallout and thus deleterious impact on human foodstocks. In this Feature, Spivak et al. review what is known of the present state of bee populations and provide information on how to mitigate and reverse the trend.

The success of all restoration efforts—and indeed, of life as we know it—depends on a healthy and diverse population of native pollinators. Pollinators are critical for seed production and the perpetuation of native plants (and our food crops). Bees are our most important pollinators in North America. Nursery managers, seed producers, and field restorationists can protect and enhance habitat for native bees. Native bees have 3 basic habitat needs. 1) Bees need a constant supply of food—a diversity of plants with overlapping blooming times so flowers are available throughout the growing season. 2) Bees need places to nest. Most native bees are solitary, and none build wax or paper structures like we associate with honey bees or wasps. Most bees nest in small warrens they construct underground, or in narrow tunnels often left behind by beetle larvae in dead trees. Bumble bees require small cavities, either in tree boles, underground (often in old rodent burrows), or under clumps of fallen grass, in which to raise their young, as well as undisturbed duff in which queens burrow and hibernate through the winter. 3) Bees need protection from most pesticides. Insecticides are primarily broad spectrum and are therefore deadly to bees. Indiscriminate herbicide use can remove many of the flowers that bees need for food. Foster bees by observing, protecting, and enhancing nesting sites and year-round sources of pollen and nectar. Vaughan M, Black SH. 2008. Native pollinators and nurseries: how to protect and enhance habitat for native bees. Native Plants Journal 9(2):80-91.

International audience; This chapter proposes a method for estimating risk to honey bees (Apis mellifera) and non-Apis bees from pesticides that are applied through sprays (acting on contact) and through seed or soil treatments and tree trunk injections (acting systemically). It describes the risk assessment process for honey bees and non-Apis bees. Problem formulation articulates the intent of the risk assessment and is predicated on particular protection goals for which the regulatory authority is responsible. The chapter illustrates the proposed risk assessment process identified by the participants of the 2011 SETAC Workshop on Pesticide Risk Assessment for Pollinators. The potential risk to adult honey bees from spray applications is assessed through calculation of an HQ. The screening-level and refined risk assessment processes for soil or seed treatment-applied pesticides incorporate different degrees of ecological realism. Screening-level assessments are typically based on conservative assumptions regarding both exposure and effects.

An essential component of an ecological risk assessment is a prediction of exposure of the organisms being assessed. This chapter outlines exposure pathways for the different pesticide delivery methods, both nonsystemic and systemic, and discusses methods used to predict pesticide exposure to honey bees and non-Apis bees. It provides an outline of techniques employed to measure pesticide residues in relevant matrices and discusses higher tier field study designs that are used to refine bee exposure assessments for specific products. The chapter presents perspectives regarding pesticide application technologies that can be employed to mitigate bee exposure, as well as future research needs to further refine exposure assessments for this taxa. Workshop participants agreed that the most significant route of exposure to bees from foliar-applied pesticides is from both contact and oral exposure to contaminated pollen, nectar, and processed food.

This chapter provides an overview of existing toxicity tests and their strengths and weaknesses, and discusses proposed modifications to existing studies, or additional studies that could address limitations in the current battery of studies. In the European Union (EU), regulatory authorities may require a bee brood feeding test to assess potential hazard of a pesticide on honey bee larvae. The chapter reports toxicity testing with some species of adult non-Apis bees with some frequency. It discusses some of the methods that have been developed to measure the potential sublethal effects of pesticides on honey bees. Laboratory toxicity tests are currently available for evaluating the potential effects of chemicals on bees. Laboratory-based studies will likely continue to focus on individual test organisms; and, although laboratory-based toxicity testing has historically focused on mortality, tests are evolving to provide insight on sublethal effects such as impaired behavior.

This chapter provides an overview of what to consider when planning or assessing either a semi-field or field study for toxicity testing. Elements in the design of semi-field and field studies encompass the study's objectives, the test organism, a study site, methods, endpoints, sample design, quality assurance and quality control standards, and the statistical analysis of the data. A semi-field study is designed to measure exposure or effects and is performed on a crop that is grown outdoors in an enclosed test system with controlled or confined exposure. A field study is designed to measure exposure or effects and is performed on a crop that is grown outdoors with no enclosure. The chapter describes the semi-field and field study for Apis and Non-Apis Bees. Monitoring schemes, for example, the UK Wildlife Incident Investigation Scheme (WIIS), rely on incidents being reported to a central organization.

American Entomologist • Summer 2008 Several non-government organizations (NGOs) in the United States have programs or projects aimed at conserving invertebrates. Organizations such as Conservation International, DiscoverLife, the American Museum of Natural History, and NatureServe, as well as many academic institutions, are documenting biodiversity across the world and developing tools for species identification. The Nature Conservancy collaborates with its partners to protect areas of habitat with exceptional biodiversity, including invertebrates; other groups, such as Defenders of Wildlife, help private landowners manage their lands for biodiversity. Zoos and academic institutions, such as the Oregon Zoo and the McGuire Center for Lepidoptera and Biodiversity, are conducting research on captive rearing and habitat needs for endangered species. Only one nonprofit organization in the United States, however, has the single mission to work exclusively on invertebrate conservation. Established in 1971, the Xerces Society is at the forefront of invertebrate conservation. For almost 40 years, the society has protected endangered species and their habitat, produced ground-breaking books on insect conservation, trained hundreds of farmers and land managers to protect and manage habitat for invertebrates, and raised awareness about the invertebrates of forests, prairies, deserts, streams, wetlands, and oceans. To fulfill its mission, the society undertakes a variety of strategies to educate the public (especially decisionmakers and land managers), create incentives for biodiversity conservation, and improve knowledge of species of concern. These strategies vary in scope from national to local, and cover a wide range of applied approaches to conservation.

American Entomologist • Volume 54, Number 2 In the case of many insects and other invertebrates, basic biology and life history information are unknown. Before protecting a species under the law, we must have, at a minimum, information on the biology, distribution, and threats to the species, not to mention clear documentation of its decline. In the long run, more funding should be allocated to invertebrate survey, systematics, taxonomy, and population ecology so that these species can be identified and cataloged and their life histories understood. ESA members are vital to this effort.

International audience; The foraging patterns of Osmia cornifrons (Radoszkowski) (Megachilidae, Hymenoptera) were determined with an immunomarking method and correlated with fruit set in a commercial tart cherry orchard in Pennsylvania. Adults of O. cornifrons were self-marked with chicken egg-white protein powder from a dispenser nest box placed at the center of the study orchard at early bloom. Flower samples were collected from randomly selected trees (n = 30) located at different distances from the nest box. Flowers were analyzed for the presence of immunomarker protein with enzyme-linked immunosorbent assay. Foraging patterns were determined by measuring the distance and direction of marked flowers from the nest box. While marked flowers were found out to 55 m (maximum distance sampled), most marked flowers were found within 35 m from the nest and the percentage of marked flowers declined rapidly beyond that distance. Fruit density per limb cross-sectional area (cm2) in the study orchard was significantly higher than in the orchard without O. cornifrons, indicating the value of O. cornifrons as pollinators in increasing fruit yield in tart cherries.

Publisher Summary This chapter highlights the endangered insects, their importance, factors causing their endangerment, and how can be they protected. The Xerces blue butterfly, Antioch katydid, Tobia's caddisfly, Roberts's alloperlan stonefly, Colorado burrowing mayfly, and Rocky Mountain grasshopper all were driven extinct by humans, and all foreshadow the fate of the world's endangered insects. With almost 1 million described species, insects eclipse all other forms of animal life on Earth, not only in sheer numbers, diversity, and biomass but also in their importance to functioning ecosystems. The sheer number and mass of insects reflect their enormous ecological impact. The world's ecosystems depend on insects for pollination, decomposition, soil aeration, and nutrient and energy cycling. Endangered species also plays a linchpin role in small, specialized systems, such as caves, oceanic islands, or some pollinator – plant relationships. To conserve insects successfully, the general public, scientists, land managers, and conservationists need to understand the extraordinary value that these organisms provide. It is unlikely that all people will develop an affinity for these animals, but it is plausible that a more compelling depiction of the contributions insects make to human welfare and survival will improve the public's attitude toward these organisms.

In this article we focus on the vital ecological services provided by insects. We restrict our focus to services provided by “wild” insects; we do not include services from domesticated or mass-reared insect species. The four insect services for which we provide value estimates—dung burial, pest control, pollination, and wildlife nutrition—were chosen not because of their importance but because of the availability of data and an algorithm for their estimation. We base our estimations of the value of each service on projections of losses that would accrue if insects were not functioning at their current level. We estimate the annual value of these ecological services provided in the United States to be at least $57 billion, an amount that justifies greater investment in the conservation of these services.