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A Common Pesticide Decreases Foraging Success and Survival in Honey Bees

Authors:
  • UMR CNRS-IRD-Université Paris-Saclay
  • Centre Apicole de Recherche et Information (CARI asbl)

Abstract

Bad News for Bees Neonicotinoid insecticides were introduced in the early 1990s and have become one of the most widely used crop pesticides in the world. These compounds act on the insect central nervous system, and they have been shown to be persistent in the environment and in plant tissues. Recently, there have been controversial connections made between neonicotinoids and pollinator deaths, but the mechanisms underlying these potential deaths have remained unknown. Whitehorn et al. (p. 351 , published online 29 March) exposed developing colonies of bumble bees to low levels of the neonicotinoid imidacloprid and then released them to forage under natural conditions. Treated colonies displayed reduced colony growth and less reproductive success, and they produced significantly fewer queens to found subsequent generations. Henry et al. (p. 348 , published online 29 March) documented the effects of low-dose, nonlethal intoxication of another widely used neonicotinoid, thiamethoxam, on wild foraging honey bees. Radio-frequency identification tags were used to determine navigation success of treated foragers, which suggested that their homing success was much reduced relative to untreated foragers.
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... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;Requier et al., 2017). The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;Requier et al., 2017). The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
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Book Available online at: https://www.bhumipublishing.com/books/ PREFACE Life Sciences have always been a fundamental area of science. The exponential increase in the quantity of scientific information and the rate, at which new discoveries are made, require very elaborate, interdisciplinary and up-to-date information and their understanding. Enhanced understanding of biological phenomenon incorporated with interdisciplinary approaches has resulted in major breakthrough products for betterment of society. To keep the view in mind we are delighted to publish our book entitled "Frontiers in Life Science Volume VII". This book is the compilation of esteemed articles of acknowledged experts in the fields of basic and applied life science. This book is published in the hopes of sharing the new research and findings in the field of life science subjects. Life science can help us unlock the mysteries of our universe, but beyond that, conquering it can be personally satisfying. We developed this digital book with the goal of helping people achieve that feeling of accomplishment. The articles in the book have been contributed by eminent scientists, academicians. Our special thanks and appreciation goes to experts and research workers whose contributions have enriched this book. We thank our publisher Bhumi Publishing, India for taking pains in bringing out the book. Finally, we will always remain a debtor to all our well-wishers for their blessings, without which this book would not have come into existence. Editors CONTENT
... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;. The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;. The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
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... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;. The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
... Since many crops depend on animal pollination for the quantity and quality of their yield, the present global reduction of insect pollinators (Potts et al., 2010) could have a severe impact on human health and food production . It is common practise to introduce managed pollinators, particularly colonies of the western honey bee (Apis mellifera), to meet the need for pollination services in crops (Garibaldi et al., 2017) Contrarily, beekeepers frequently keep managed colonies, at least for a while, away from agriculture, even in regulated regions (Henry et al., 2012) because agricultural landscapes negatively affect honey bee survival through, for example, chemical exposure and narrow flower supply (Potts et al., 2010;Potts et al., 2016;Henry et al., 2012;. The latest research has demonstrated that the introduction of numerous managed colonies into places that are protected may have a negative impact on wild bee colonies (Danner et al., 2016;Thomson, 2016;Geslin et al., 2017;Magrach et al., 2017;Malinger et al., 2017;Norfolt et al., 2018). ...
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... However, the exact causes of this decline are unclear and are still debated in academic circles. In some cases, pesticides appear to negatively affect the health of organisms that spend more time foraging in the fields, such as bumblebees, and this may, in turn, lead to low survival of entire colonies (Henry et al. 2012;Campbell et al. 2019). Landscape changes, due to intensive crops, human land management, or climate change, can be equally or even more harmful for pollinators than pesticides (Holzschuh et al. 2008;CaraDonna et al. 2018). ...
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... Bumblebees are among the most important pollinators in temperate zones, and several species are reared at industrial scales for the purpose of commercial crop pollination, largely in greenhouses [37]. Studies on the effects of neonics on bumblebee biology have revealed a broad spectrum of sublethal negative effects that include reduced food consumption and nest growth [32,38], colony initiation [39,40] and interactions among nestmates [41], and compromised foraging and homing abilities [42][43][44]. Their canonical effects on the cholinergic system cannot easily explain some of these harmful effects. For example, there is evidence that exposure to neonics resulted in attenuated immune defense [45] and reduced fertility [38,[46][47][48]. ...
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... A major additional threat connected to modern agriculture is posed by pesticides, which are considered the second major driver of insect declines (6,7). Much attention has focused on neonicotinoid pesticides, which have severe negative effects on the growth and survival of artificially exposed bee colonies (41)(42)(43). In addition, areas in the vicinity of crops treated with a neonicotinoid pesticide contain fewer solitary bees and reduced growth of bumblebee colonies (44). ...
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The population dynamics of eusocial insects differ significantly from those of non-eusocial animals. With eusocial insects, one has to distinguish between a population of colonies and the population of individuals inside each colony. These two levels are closely related, because the decision whether a colony reproduces or not is mainly determined by its intracolonial population and resource status. In addition, a population's rate of colony mortality is strongly dependent on each colony's intracolonial status. Honeybees collect their food in the environment, their most important ecological aspect is the pollinating of plants. In recent empirical studies, we demonstrated the importance of food supply on the population dynamics of honeybee colonies. In addition, honeybees show division of labor, which occurs in the form of age polyethism, meaning that morphologically almost identical worker bees choose their tasks mainly dependent on age. This task selection system is very flexible and is significantly affected by changes in task-specific workloads or in the age structure of the colony. Recent studies have shown that environmental factors and/or natural or experimental changes in resource supply heavily affect the age structure, resulting in changes in task allocation within the colony. These changes further affect the intracolony population dynamics and age structure. This situation can be described as a set of delayed feedback loops. We created a mathematically simple honeybee population model (HoPoMo) using difference equations to model the population dynamics and the resource dynamics of a honeybee colony. Our model emphasizes the importance of pollen supply and of brood cannibalism, an aspect that was neglected by other honeybee population models so far. HoPoMo includes simple models of task selection and of nutrient allocation. It allows us to simulate a variety of colony conditions (colony size, intrinsic bee characteristics, resource status) and a variety of environmental conditions (rain, temperature, botanical resource availability). The model can be easily parameterized with real weather data and with experimental colony treatments, so that we can use the model to interpret empirical experimental data. We successfully compared the predictions of our model with data gained from the literature and from own experiments. Extensive sensitivity analysis revealed that the model's predictions of population dynamics are very stable, except at very low mortality rates. And finally, we demonstrate, that the model can be used for several environmental conditions of honeybee living: controlled bee hives, scientifically used colonies and wild-life honeybees.
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In spite of the tremendous public interest in the recent large honeybee losses attributed to colony collapse disorder, there is still no definitive explanation for the phenomenon. With the hypothesis that nutritional stress due to habitat loss has played an important role in honeybee colony collapse, I analyze the land use data in United States to show that the colony loss suffered by each state is significantly predicted by the extent of its open land relative to its developed land area. I provide further support for this hypothesis by showing that states with the largest areas of open land have a significantly higher honey yield on a per colony basis. I discuss how increasing loss of foraging resources could be synergistically acting with emerging diseases to stress honeybee populations and the importance therefore for preserving natural areas that act as important pollinator habitats.