scholarly journals Pesticide exposure affects flight dynamics and reduces flight endurance in bumblebees

2018 ◽  
Author(s):  
Daniel Kenna ◽  
Hazel Cooley ◽  
Ilaria Pretelli ◽  
Ana Ramos Rodrigues ◽  
Steve D. Gill ◽  
...  
Keyword(s):  
Agricultural Land ◽  
Pesticide Exposure ◽  
Bombus Terrestris ◽  
Central Place ◽  
Foraging Efficiency ◽  
Flight Performance ◽  
Insect Pollinator ◽  
Exposed Workers ◽  
Flight Mills ◽  
Summary Statement

AbstractThe emergence of agricultural land use change creates a number of challenges that insect pollinators, such as eusocial bees, must overcome. Resultant fragmentation and loss of suitable foraging habitats, combined with pesticide exposure, may increase demands on foraging, specifically the ability to reach resources under such stress. Understanding the effect that pesticides have on flight performance is therefore vital if we are to assess colony success in these changing landscapes. Neonicotinoids are one of the most widely used classes of pesticide across the globe, and exposure to bees has been associated with reduced foraging efficiency and homing ability. One explanation for these effects could be that elements of flight are being affected, but apart from a couple of studies on the honeybee, this has scarcely been tested. Here we used flight mills to investigate how exposure to a field realistic (10ppb) acute dose of imidacloprid affected flight performance of a wild insect pollinator - the bumblebee, Bombus terrestris audax. Intriguingly, intial observations showed exposed workers flew at a significantly higher velocity over the first ¾ km of flight. This apparent hyperactivity, however, may have a cost as exposed workers showed reduced flight distance and duration to around a third of what control workers were capable of achieving. Given that bumblebees are central place foragers, impairment to flight endurance could translate to a decline in potential forage area, decreasing the abundance, diversity and nutritional quality of available food, whilst potentially diminishing pollination service capabilities.Summary StatementAcute neonicotinoid exposure impaired flight endurance and affected velocity of Bombus terrestris workers, which may dramatically reduce colony foraging potential and pollination provision in pesticide applied landscapes.

Epigenetic study of global gene methylation in PON1, XRCC1 and GSTs different genotypes in rural and urban pesticide exposed workers

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Amal Saad-Hussein ◽  
Mona Mohamed Taha
Keyword(s):  
Dna Methylation ◽  
Dietary Habits ◽  
Pesticide Exposure ◽  
Alu Elements ◽  
Adverse Health Effects ◽  
Rural And Urban ◽  
Environmental Determinants Of Health ◽  
Pcr Rflp ◽  
Exposed Workers ◽  
Health And Disease

AbstractBackgroundEpigenetic represents a study of occurred heritable gene expression changes without changing in the DNA sequence. It includes DNA methylation and miRNA expression that attract increasing attention as potential links between the genetic and environmental determinants of health and disease. Pesticide exposure is associated with adverse health effects and DNA methylation due to oxidative stress induced following its exposure. This study aimed to define the association of genetic polymorphisms of XRCC1, PON1, GSTP1 and GST genes with global genes DNA methylation in urban and rural occupationally pesticides exposed workers.MethodsThis study included 100 pesticides exposed workers; 50 rural sprayers (RE) and 50 urban researchers (UE). Controls included equal numbers. DNA methylation of global genes was evaluated by pyrosequencing assay. XRCC1, PON1 and GSTP1 genotyping were assessed by PCR–RFLP, and GST M1 and T1 were performed by PCR.ResultsThe results of this study revealed that most genotypes in XRCC1, PON1, GSTP1 and GST genes were associated with LINE-1 hypomethylation among UE group. However, heterozygote genotypes (Gln-Arg and Ile-Val) in XRCC1 and GSTP1 genes, respectively, were associated with LINE-1 hypermethylation among UE compared with other corresponding genotypes. Only GSTT1 polymorphism recorded a significant change in percent methylation of Alu elements among urban and rural groups.ConclusionUrbanization could play an additional risk for epigenetic changes associated with pesticide exposure, and that could be attributed to the quality of life including their dietary habits, working and living in closed areas, and their exposure to extra pollutions emitted from urbanization sources.

scholarly journals Multiple-stage decisions in a marine central-place forager

2016 ◽  
Vol 3 (5) ◽  
pp. 160043 ◽  
Author(s):  
Ari S. Friedlaender ◽  
David W. Johnston ◽  
Reny B. Tyson ◽  
Amanda Kaltenberg ◽  
Jeremy A. Goldbogen ◽  
...  
Keyword(s):  
Foraging Behaviour ◽  
Central Place ◽  
Foraging Efficiency ◽  
Feeding Rates ◽  
Marine Animals ◽  
Air Breathing ◽  
Baleen Whales ◽  
Multi Stage ◽  
Central Place Forager ◽  
Prey Patches

Air-breathing marine animals face a complex set of physical challenges associated with diving that affect the decisions of how to optimize feeding. Baleen whales (Mysticeti) have evolved bulk-filter feeding mechanisms to efficiently feed on dense prey patches. Baleen whales are central place foragers where oxygen at the surface represents the central place and depth acts as the distance to prey. Although hypothesized that baleen whales will target the densest prey patches anywhere in the water column, how depth and density interact to influence foraging behaviour is poorly understood. We used multi-sensor archival tags and active acoustics to quantify Antarctic humpback whale foraging behaviour relative to prey. Our analyses reveal multi-stage foraging decisions driven by both krill depth and density. During daylight hours when whales did not feed, krill were found in deep high-density patches. As krill migrated vertically into larger and less dense patches near the surface, whales began to forage. During foraging bouts, we found that feeding rates (number of feeding lunges per hour) were greatest when prey was shallowest, and feeding rates decreased with increasing dive depth. This strategy is consistent with previous models of how air-breathing diving animals optimize foraging efficiency. Thus, humpback whales forage mainly when prey is more broadly distributed and shallower, presumably to minimize diving and searching costs and to increase feeding rates overall and thus foraging efficiency. Using direct measurements of feeding behaviour from animal-borne tags and prey availability from echosounders, our study demonstrates a multi-stage foraging process in a central place forager that we suggest acts to optimize overall efficiency by maximizing net energy gain over time. These data reveal a previously unrecognized level of complexity in predator–prey interactions and underscores the need to simultaneously measure prey distribution in marine central place forager studies.

Disembedded Capitals Reconsidered

1980 ◽  
Vol 45 (1) ◽  
pp. 132-145 ◽  
Author(s):  
Robert S. Santley
Keyword(s):  
Agricultural Land ◽  
Evolutionary Model ◽  
Central Place ◽  
Craft Specialization ◽  
Local Market ◽  
Political Strategy ◽  
Site Location ◽  
Labor Input ◽  
Monte Alban ◽  
Valley Of Oaxaca

The concept of a disembedded capital is viewed as a specious construct. The logical foundations of disembeddedness of political authority from local commerical hierarchies are viewed as largely untenable, at least in prehispanic Mesoamerica, and the close parallels between Monte Albán and Teotihuacán in terms of general site location, access to prime agricultural land, level of craft specialization required to meet local needs, and local market patterns suggest that both sites had similar roles with respect to local central-place support hierarchies. An alternative evolutionary model is then offered, one which relates developments manifest in the Basin of Mexico and in the Valley of Oaxaca to an economic and political strategy which seeks to minimize labor input and amount of systemic risk.

scholarly journals Toxicity of new fungicides for eukaryotic microorganisms isolated from the gut of the food-important vegetable pollinator Bombus terrestris L.

2021 ◽  
Vol 82 (4) ◽  
pp. 54-59
Author(s):  
M. Y. Syromyatnikov ◽  
O. V. Savinkova ◽  
V. N. Popov
Keyword(s):  
Food Security ◽  
Synergistic Effect ◽  
Bombus Terrestris ◽  
Mycelial Fungi ◽  
Agricultural Crops ◽  
Rhodotorula Mucilaginosa ◽  
Sharp Decline ◽  
Insect Pollinator ◽  
Eukaryotic Microorganisms ◽  
Penicillium Commune

Currently, there is a trend in decreasing of the number of pollinators, which is already a matter of food security. Bumblebees Bombus terrestris L. are economically important pollinators of vegetables and other agricultural crops. Recently, it has been suggested that the synergistic effect of pesticides and diseases that affect pollinators contributes to a sharp decline in the number of pollinators. In this work, we investigated the effect of new biodegradable fungicides on eukaryotic microorganisms Penicillium commune and Rhodotorula mucilaginosa isolated from the gut of Bombus terrestris L. larvae. It was shown that the new fungicides studied can inhibit the growth of both mycelial eukaryotic microorganisms and yeast eukaryotic microorganisms. Among the studied substances, the most effective was fungicide 2. The studied substances are selectively toxic only for eukaryotic microorganisms and do not have a toxic effect on animals, in particular insects, and can be used to treat insect pollinator infections caused by fungal microorganisms. It was noted that the new fungicides are more toxic to yeast than to mycelial fungi.

scholarly journals Subjective Symptoms of Male Workers Linked to Occupational Pesticide Exposure on Coffee Plantations in the Jarabacoa Region, Dominican Republic

2018 ◽  
Vol 15 (10) ◽  
pp. 2099 ◽  
Author(s):  
Hans-Peter Hutter ◽  
Michael Kundi ◽  
Kathrin Lemmerer ◽  
Michael Poteser ◽  
Lisbeth Weitensfelder ◽  
...  
Keyword(s):  
Pesticide Exposure ◽  
Acute Effects ◽  
Safety Equipment ◽  
Coffee Plantations ◽  
Excessive Salivation ◽  
Exposed Workers ◽  
Organic Farmers ◽  
Coffee Farmers ◽  
Reported Health ◽  
Precautionary Measures

Acute and sub-acute effects of pesticide use in coffee farmers have rarely been investigated. In the present field study, self-reported health symptoms from 38 male pesticide users were compared to those of 33 organic farmers. Results of cytological findings have been reported in an accompanying paper in this issue. The present second part of the study comprises a questionnaire based survey for various, potentially pesticide related symptoms among the coffee farmers. Symptom rates were generally higher in exposed workers, reaching significance in nine out of 19 assessed symptoms. Significantly increased symptom frequencies were related to neurotoxicity, parasympathic effects and acetylcholine esterase inhibition, with the highest differences found for excessive salivation, dizziness and stomach ache. We revealed a lack of precautionary measures in the majority of farmers. Better education, regulations, and safety equipment are urgently needed.

scholarly journals Using Temporally Resolved Floral Resource Maps to Explain Bumblebee Colony Performance in Agricultural Landscapes

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1993
Author(s):  
Philipp W. Eckerter ◽  
Lars Albus ◽  
Sharumathi Natarajan ◽  
Matthias Albrecht ◽  
Lolita Ammann ◽  
...  
Keyword(s):  
Agricultural Land ◽  
Bombus Terrestris ◽  
Colony Growth ◽  
Agricultural Landscapes ◽  
Wild Plants ◽  
Floral Resources ◽  
Colony Development ◽  
Pollination Services ◽  
Spatio Temporal ◽  
Floral Resource

Wild bumblebees are key pollinators of crops and wild plants that rely on the continuous availability of floral resources. A better understanding of the spatio-temporal availability and use of floral food resources may help to promote bumblebees and their pollination services in agricultural landscapes. We placed colonies of Bombus terrestris L. in 24 agricultural landscapes with various degrees of floral resource availability and assessed different parameters of colony growth and fitness. We estimated pollen availability during different periods of colony development based on detailed information of the bumblebee pollen diet and the spatial distribution of the visited plant species. Total pollen availability did not significantly explain colony growth or fitness. However, when using habitat maps, the weight gain of colonies, the number of queen cells, and colony survival decreased with increasing distance from the forest. The better explanation of bumblebee performance by forest proximity than by (plant-inferred) pollen availability indicates that other functions of forests than pollen provision were important. The conservation of forests next to agricultural land might help to sustain high populations of these important wild pollinators and enhance their crop pollination services. Combining different mapping approaches might help to further disentangle complex relationships between B. terrestris and their environment in agricultural landscapes.

Displacement of Tasmanian native megachilid bees by the recently introduced bumblebee Bombus terrestris (Linnaeus, 1758) (Hymenoptera : Apidae)

1999 ◽  
Vol 47 (1) ◽  
pp. 59 ◽  
Author(s):  
Peter B. McQuillan ◽  
Andrew B. Hingston
Keyword(s):  
Exotic Species ◽  
Bombus Terrestris ◽  
Limited Resource ◽  
Foraging Efficiency ◽  
Native Bees ◽  
Ambient Temperatures ◽  
The Impact

The assertion that the recently introduced large earth bumblebee, Bombus terrestris, does not compete with other bees was investigated by examining the impact of B. terrestris on the foraging of two species of Chalicodoma(Megachilidae) on flowers of Gompholobium huegelii (Fabaceae). Chalicodoma spp. spent less time at each flower during the afternoon in quadrats where B. terrestris foraged than at quadrats from which B. terrestriswas excluded, indicating that standing crops of nectar were depleted by B. terrestris during the course of the day. This decline in resources was associated with reductions in the numbers of flowers visited, and the amount of time spent foraging, by Chalicodoma spp. It is proposed that the native bees avoided foraging in the quadrat where B. terrestris occurred as a response to reduced foraging efficiency in that situation. Thus, B. terrestris displaced these two species of Chalicodoma through competition for a limited resource. The high densities at which B. terrestris occurred, together with its ability to forage at lower ambient temperatures than the native bees, exacerbated the impact of this exotic species. The possibility that this will adversely affect pollination in G. huegelii is also discussed.

scholarly journals Cytotoxic and Genotoxic Effects of Pesticide Exposure in Male Coffee Farmworkers of the Jarabacoa Region, Dominican Republic

2018 ◽  
Vol 15 (8) ◽  
pp. 1641 ◽  
Author(s):  
Hans-Peter Hutter ◽  
Abdul Khan ◽  
Kathrin Lemmerer ◽  
Peter Wallner ◽  
Michael Kundi ◽  
...  
Keyword(s):  
Dominican Republic ◽  
Organic Farming ◽  
Pesticide Exposure ◽  
Field Studies ◽  
Cell Integrity ◽  
Buccal Cells ◽  
Genotoxic Effects ◽  
Local Conditions ◽  
Exposed Workers ◽  
The Impact

Intensive agrochemical use in coffee production in the Global South has been documented. The aim of this study was to investigate cytotoxic and genotoxic effects of pesticide exposure in male farmworkers in the Dominican Republic comparing conventional farming using pesticides to organic farming. Furthermore, feasibility of the buccal micronucleus cytome assay (BMCA) for field studies under difficult local conditions was tested. In a cross-sectional field study, pesticide exposed (sprayers) and non-exposed male workers on coffee plantations were interviewed about exposure history, and pesticide application practices. Buccal cells were sampled, and BMCA was applied to assess potential effects on cell integrity. In total, 38 pesticide-exposed and 33 non-exposed workers participated. Eighty-four and 87%, respectively, of the pesticide-exposed respondents did not use masks or gloves at all. All biomarkers from the BMCA were significantly more frequent among exposed workers—odds ratio for micronucleated cells: 3.1 (95% confidence interval: 1.3–7.4) or karyolysis: 1.3 (1.1–1.5). Buccal cells as sensitive markers of toxic oral or respiratory exposures proved feasible for challenging field studies. Our findings indicate that the impact of pesticide use is not restricted to acute effects on health and wellbeing, but also points to long-term health risks. Therefore, occupational safety measures including training and protective clothing are needed, as well as encouragement towards minimal application of pesticides and more widespread use of organic farming.

scholarly journals Ecology dictates the value of memory for foraging bees

2021 ◽  
Author(s):  
Christopher D. Pull ◽  
Irina Petkova ◽  
Cecylia Watrobska ◽  
Grégoire Pasquier ◽  
Marta Perez Fernandez ◽  
...  
Keyword(s):  
Short Term Memory ◽  
Foraging Ecology ◽  
Bombus Terrestris ◽  
Single Species ◽  
Foraging Efficiency ◽  
Short Term ◽  
Selection Pressures ◽  
Term Memory ◽  
Ecological Selection ◽  
Cognitive Trait

Summary“Ecological intelligence” hypotheses posit that the benefits of cognitive investment vary with foraging ecology, and provide a key framework for understanding the evolution of animal learning and memory1–4. However, although certain ecological selection pressures have been found to correlate with brain or neural region size5–8, empirical evidence to show that any specific cognitive trait is useful in certain environments but not others is currently lacking. Here, we assay the short-term memory of bumblebee (Bombus terrestris audax) workers from 25 identically reared colonies, before allowing each colony to forage in a landscape where forage availability varies seasonally. Through analysis of the bees’ lifetime foraging careers, comprising >1700 foraging trips over two years, we show that performance on a task designed to test short-term memory predicts individual foraging efficiency – a fitness proxy that is key to colony reproductive output – in plentiful spring foraging conditions. However, this relationship is reversed during the summer floral dearth, when the costs of cognitive investment may outweigh the benefits. Our results provide evidence that the value of a cognitive trait depends upon the prevailing ecological conditions and suggest that temporal changes in that environment could place contrasting selection pressures on memory within a single species.

Sign in / Sign up

Export Citation Format

Share Document