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James H. Cane

Bio: James H. Cane is an academic researcher from Utah State University. The author has contributed to research in topics: Pollinator & Pollination. The author has an hindex of 41, co-authored 129 publications receiving 11260 citations. Previous affiliations of James H. Cane include Agricultural Research Service & United States Department of Agriculture.
Topics: Pollinator, Pollination, Pollen, Apoidea, Megachilidae


Papers
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Journal ArticleDOI
TL;DR: It is found that fruit, vegetable or seed production from 87 of the leading global food crops is dependent upon animal pollination, while 28 crops do not rely upon animalPollination, however, global production volumes give a contrasting perspective.
Abstract: The extent of our reliance on animal pollination for world crop production for human food has not previously been evaluated and the previous estimates for countries or continents have seldom used primary data. In this review, we expand the previous estimates using novel primary data from 200 countries and found that fruit, vegetable or seed production from 87 of the leading global food crops is dependent upon animal pollination, while 28 crops do not rely upon animal pollination. However, global production volumes give a contrasting perspective, since 60% of global production comes from crops that do not depend on animal pollination, 35% from crops that depend on pollinators, and 5% are unevaluated. Using all crops traded on the world market and setting aside crops that are solely passively self-pollinated, wind-pollinated or parthenocarpic, we then evaluated the level of dependence on animal-mediated pollination for crops that are directly consumed by humans. We found that pollinators are essential for 13 crops, production is highly pollinator dependent for 30, moderately for 27, slightly for 21, unimportant for 7, and is of unknown significance for the remaining 9. We further evaluated whether local and landscape-wide management for natural pollination services could help to sustain crop diversity and production. Case studies for nine crops on four continents revealed that agricultural intensification jeopardizes wild bee communities and their stabilizing effect on pollination services at the landscape scale.

4,830 citations

Journal ArticleDOI
TL;DR: The work group encourages increased education and training to ensure that both the lay public and resource managers understand that pollination is one of the most important ecological services provided to agriculture through the responsible management and protection of wildland habitats and their populations of pollen-vectoring animals and nectar-producing plants.
Abstract: Following reports of dramatic declines in managed and feral honey bees from nearly every region of North America, scientists and resource managers from the U.S., Mexico, and Canada came together to review the quality of the evidence that honey bees as well as other pollinators are in long-term decline and to consider the potential consequences of these losses on the conservation of biodiversity and the stability of the yield of food crops. These experts in pollination ecology confirmed that the last 5 years of losses of honeybee colonies in North America leave us with fewer managed pollinators than at any time in the last 50 years and that the management and protection of wild pollinators is an issue of paramount importance to our food supply system. Although there are conclusive data that indicate 1200 wild vertebrate pollinators may be at risk, data on the status of most invertebrate species that act as pollination agents is lacking. The recommendations from a working group of over 20 field scientists, presented here, have been endorsed by 14 conservation and sustainable agriculture organizations, research institutes, and professional societies, including the Society for Conservation Biology. Among the most critical priorities for future research and conservation of pollinator species are (1) increased attention to invertebrate systematics, monitoring, and reintroduction as part of critical habitat management and restoration plans; (2) multi-year assessments of the lethal and sublethal effects of pesticides, herbicides, and habitat fragmentation on wild pollinator populations in and near croplands; (3) inclusion of the monitoring of seed and fruit set and floral visitation rates in endangered plant management and recovery plans; (4) inclusion of habitat needs for critically-important pollinators in the critical habitat designations for endangered plants; (5) identification and protection of floral reserves near roost sites along the “nectar corridors” of threatened migratory pollinators; and (6) investment in the restoration and management of a diversity of pollinators and their habitats adjacent to croplands in order to stabilize or improve crop yields. The work group encourages increased education and training to ensure that both the lay public and resource managers understand that pollination is one of the most important ecological services provided to agriculture through the responsible management and protection of wildland habitats and their populations of pollen-vectoring animals and nectar-producing plants. Consecuencias Potenciales de la Disminucion de Polinizadores en la Conservacion de la Biodiversidad y la Estabilidad en la Produccion de Cosechas de Alimentos Resumen: Debido a los constantes reportes de disminuciones dramaticas de abejas productoras de miel tanto manejadas como silvestres en casi todas las regiones de Norteamerica, cientificos y manejadores de recursos de Estados Unidos, Mexico y Canada se reunieron para revisar la calidad de las evidencias de que las abejas, asi como otros polinizadores se encuentran en una disminucion a largo plazo y para considerer las consecuencias potenciales de estas perdidas en la conservacion de la biodiversidad y la estabilidad de las cosechas de alimentos. Estos expertos en ecologia de la polinizacion confirmaron que los ultimos cinco anos de perdidas de colonias de abejas en Norteamerica nos ubican con menos polinizadores manejados que en ningun otro momento en los ultimos 50 anos y que el manejo y proteccion de polinizadores silvestres es un aspecto de suma importancia para nuestro sistema de abastecimiento de alimentos. A pesar de que existen datos concluyentes que indican que 1200 polinizadores vertebrados silvestres podrian encontrarse en riesgo, se carece de datos sobre la situacion de la mayoria de las especies de invertebrados que actuan como polinizadores. Las recomendaciones de un grupo de trabajo de mas de 20 cientificos, presentadas aqui, han sido respaldadas por 14 organizaciones de conservacion y agricultura sustentable, institutos de investigacion y sociedades de profesionistas incluyendo la Sociedad para la Biologia de la Conservacion. Entre las prioridades mas criticas de investigacion y conservacion de especies de polinizadores se encuentran; 1) incrementar el enfoque en sistematica de invertebrados, monitoreo y reintroduccion como parte del manejo de habitat critico y planes de restauracion; 2) evaluaciones de varios anos de los efectos letales y subletales de pesticidas, herbicidas y la fragmentacion del habitat en las poblaciones silvestres de polinizadores dentro y alrededor de las 10 Pollinator Declines Allen-Wardell et al. Conservation Biology Volume 12, No. 1, February 1998 tierras de cosechas; 3) inclusion del monitoreo de semillas y frutas y las tasas de visita en los planes de manejo y recuperacion de plantas; 4) inclusion de las necesidades de habitat para polinizadores criticamente importates en las designaciones de habitat critico para plantas amenazadas; 5) identification y proteccion de reservas florales cerca de sitios de percha a lo largo de “corredores de nectar” de polinizadores migratorios amenazados; y 6) inversion en la investigacion y manejo de una diversidad de polinizadores y sus habitats adyacentes a sitios con cosechas para poder estabilizar e improvisar la produccion de las cosechas. El grupo de trabajo hace un llamado para estimular un incremento en educacion y entrenamiento para asegurar que tanto el publico como los manejadores de recursos entiendan que la polinizacion es uno de los servicios ecologicos mas importantes aportados a la agricultura a traves del manejo responsable y la proteccion de habitats silvestres y de sus poblaciones de animales vectores de polen y plantas productoras de nectar.

884 citations

Book ChapterDOI
TL;DR: Study on the mechanism(s) of pollen digestion remain inconclusive, but suggest that differences in digestibility among pollen types may reflect differences in pollen wall porosity, thickness, and composition.
Abstract: This paper reviews the literature concerning digestion and nutrient content of pollen. Four topics are addressed in detail: 1) The mechanism of pollen digestion by animals; 2) The efficiency of mechanical and digestive removal of pollen content by various animals; 3) Range and taxonomic distribution of pollen nutrients, and 4) Adaptive hypotheses proposed to associate pollen chemistry with pollinator reward. Studies on the mechanism(s) of pollen digestion remain inconclusive, but suggest that differences in digestibility among pollen types may reflect differences in pollen wall porosity, thickness, and composition. Although hummingbirds reportedly digest pollen very poorly, most animals studied, including those that do not regularly consume pollen, can digest 50–100% of ingested grains. Overlooked and recent research of pollen protein content shows that pollen grains may contain over 60% protein, double the amount cited in some studies of pollen-feeding animals. Adaptive hypotheses that associate pollen starch and pollen caloric content with pollinator reward remain unsubstantiated when critically viewed through the lens of phylogeny.

590 citations

Journal ArticleDOI
TL;DR: This database compares pollen protein concentration with pollination mode, pollen collection by bees, and distance from stigma to ovule, after accounting for phylogeny through paired phylogenetic comparisons and a nested ANOVA including taxonomic rank.
Abstract: Pollen ranges from 25% to 61% protein content Most pollen proteins are likely to be enzymes that function during pollen tube growth and subsequent fertilization, but the vast range of protein quantity may not reflect only pollen–pistil interactions Because numerous vertebrate and invertebrate floral visitors consume pollen for protein, protein content may influence floral host choice Additionally, many floral visitors pollinate their host plants If protein content influences pollinator visitation, then pollinators are hypothesized to select for increased protein content of host plants We analyzed or gleaned from the literature crude pollen protein concentrations of 377 plant species from 93 plant families Using this database, we compared pollen protein concentration with (1) pollination mode, (2) pollen collection by bees, and (3) distance from stigma to ovule, after accounting for phylogeny through paired phylogenetic comparisons and a nested ANOVA including taxonomic rank We found that pollen pr

466 citations

Journal ArticleDOI
TL;DR: Overall, bee response to urban habitat fragmentation was best predicted by ecological traits associated with nesting and dietary breadth, had species been treated as individual units in the analyses, or pooled together into one analysis, these response patterns may not have been apparent.
Abstract: Urbanization within the Tucson Basin of Arizona during the past 50+ years has fragmented the original desert scrub into patches of different sizes and ages. These remnant patches and the surrounding desert are dominated by Larrea tridentata (creosote bush), a long-lived shrub whose flowers are visited by > 120 native bee species across its range. Twenty-one of these bee species restrict their pollen foraging to L. tridentata. To evaluate the response of this bee fauna to fragmentation, we compared species incidence and abundance patterns for the bee guild visiting L. tridentata at 59 habitat fragments of known size (0.002-5 ha) and age (up to 70 years), and in adjacent desert. The 62 bee species caught during this study responded to fragmentation heterogeneously and not in direct relation to their abundance or incidence in undisturbed desert. Few species found outside the city were entirely absent from urban fragments. Species of ground-nesting L. tridentata specialists were underrepresented in smaller fragments and less abundant in the smaller and older fragments. In contrast, cavity-nesting bees (including one L. tridentata specialist) were overrepresented in the habitat fragments, probably due to enhanced nesting opportunities available in the urban matrix. Small-bodied bee species were no more likely than larger bodied species to be absent from the smaller fragments. The introduced European honey bee, Apis mellifera, was a minor faunal element at > 90% of the fragments and exerted little if any influence on the response of native bee species to fragmentation. Overall, bee response to urban habitat fragmentation was best predicted by ecological traits associated with nesting and dietary breadth. Had species been treated as individual units in the analyses, or pooled together into one analysis, these response patterns may not have been apparent. Pollination interactions with this floral host are probably not adversely affected in this system because of its longevity and ability to attract diverse pollinators but will demand careful further study to understand.

335 citations


Cited by
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Journal ArticleDOI
TL;DR: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols used xiii 1.
Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

14,171 citations

Journal ArticleDOI
TL;DR: It is found that fruit, vegetable or seed production from 87 of the leading global food crops is dependent upon animal pollination, while 28 crops do not rely upon animalPollination, however, global production volumes give a contrasting perspective.
Abstract: The extent of our reliance on animal pollination for world crop production for human food has not previously been evaluated and the previous estimates for countries or continents have seldom used primary data. In this review, we expand the previous estimates using novel primary data from 200 countries and found that fruit, vegetable or seed production from 87 of the leading global food crops is dependent upon animal pollination, while 28 crops do not rely upon animal pollination. However, global production volumes give a contrasting perspective, since 60% of global production comes from crops that do not depend on animal pollination, 35% from crops that depend on pollinators, and 5% are unevaluated. Using all crops traded on the world market and setting aside crops that are solely passively self-pollinated, wind-pollinated or parthenocarpic, we then evaluated the level of dependence on animal-mediated pollination for crops that are directly consumed by humans. We found that pollinators are essential for 13 crops, production is highly pollinator dependent for 30, moderately for 27, slightly for 21, unimportant for 7, and is of unknown significance for the remaining 9. We further evaluated whether local and landscape-wide management for natural pollination services could help to sustain crop diversity and production. Case studies for nine crops on four continents revealed that agricultural intensification jeopardizes wild bee communities and their stabilizing effect on pollination services at the landscape scale.

4,830 citations

Journal ArticleDOI
TL;DR: The nature and extent of reported declines, and the potential drivers of pollinator loss are described, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them are reviewed.
Abstract: Pollinators are a key component of global biodiversity, providing vital ecosystem services to crops and wild plants. There is clear evidence of recent declines in both wild and domesticated pollinators, and parallel declines in the plants that rely upon them. Here we describe the nature and extent of reported declines, and review the potential drivers of pollinator loss, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them. Pollinator declines can result in loss of pollination services which have important negative ecological and economic impacts that could significantly affect the maintenance of wild plant diversity, wider ecosystem stability, crop production, food security and human welfare.

4,608 citations

Journal ArticleDOI
27 Mar 2015-Science
TL;DR: The stresses bees are experiencing from climate change, infectious diseases, and insecticides are reviewed, with concern that the authors may be nearing a “pollination crisis” in which crop yields begin to fall.
Abstract: Bees are subject to numerous pressures in the modern world. The abundance and diversity of flowers has declined, bees are chronically exposed to cocktails of agrochemicals, and they are simultaneously exposed to novel parasites accidentally spread by humans. Climate change is likely to exacerbate these problems in the future. Stressors do not act in isolation; for example pesticide exposure can impair both detoxification mechanisms and immune responses, rendering bees more susceptible to parasites. It seems certain that chronic exposure to multiple, interacting stressors is driving honey bee colony losses and declines of wild pollinators, but such interactions are not addressed by current regulatory procedures and studying these interactions experimentally poses a major challenge. In the meantime, taking steps to reduce stress on bees would seem prudent; incorporating flower-rich habitat into farmland, reducing pesticide use through adopting more sustainable farming methods, and enforcing effective quarantine measures on bee movements are all practical measures that should be adopted. Effective monitoring of wild pollinator populations is urgently needed to inform management strategies into the future.

2,526 citations

Journal ArticleDOI
01 Mar 2011-Oikos
TL;DR: The global number and proportion of animal pollinated angiosperms is estimated as 308 006, which is 87.5% of the estimated species-level diversity of fl owering plants.
Abstract: It is clear that the majority of fl owering plants are pollinated by insects and other animals, with a minority utilising abiotic pollen vectors, mainly wind. However there is no accurate published calculation of the proportion of the ca 352 000 species of angiosperms that interact with pollinators. Widely cited fi gures range from 67% to 96% but these have not been based on fi rm data. We estimated the number and proportion of fl owering plants that are pollinated by animals using published and unpublished community-level surveys of plant pollination systems that recorded whether each species present was pollinated by animals or wind. Th e proportion of animal-pollinated species rises from a mean of 78% in temperate-zone communities to 94% in tropical communities. By correcting for the latitudinal diversity trend in fl owering plants, we estimate the global number and proportion of animal pollinated angiosperms as 308 006, which is 87.5% of the estimated species-level diversity of fl owering plants. Given current concerns about the decline in pollinators and the possible resulting impacts on both natural communities and agricultural crops, such estimates are vital to both ecologists and policy makers. Further research is required to assess in detail the absolute dependency of these plants on their pollinators, and how this varies with latitude and community type, but there is no doubt that plant – pollinator interactions play a signifi cant role in maintaining the functional integrity of most terrestrial ecosystems. Plant – pollinator relationships may be one of the most ecologically important classes of animal – plant interaction: without pollinators, many plants could not set seed and reproduce; and without plants to provide pollen, nectar and other rewards, many animal populations would decline, with consequent knock-on eff ects for other species (Kearns et al.

2,448 citations