Survey of Pathogens and Parasites of Bumble Bees (Bombus Latreille Spp.) in Illinois and Selected Areas of Northern California and Southern Oregon PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Survey of Pathogens and Parasites of Bumble Bees (Bombus Latreille Spp.) in Illinois and Selected Areas of Northern California and Southern Oregon PDF full book. Access full book title Survey of Pathogens and Parasites of Bumble Bees (Bombus Latreille Spp.) in Illinois and Selected Areas of Northern California and Southern Oregon by Christina M. North. Download full books in PDF and EPUB format.
Author: Christina M. North
Publisher:
ISBN:
Category :
Languages : en
Pages : 150
Get Book Here
Book Description
Author: Christina M. North
Publisher:
ISBN:
Category :
Languages : en
Pages : 150
Get Book Here
Book Description
Author: Elena Gratton
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Bumble bees (Bombus spp) are critical pollinators contributing to native ecosystems as well as agricultural production. At least half of the studied bumble bee species in North America are experiencing population declines and range contractions due to interacting factors such as habitat loss, climate change, invasive species, and pathogens. Pathogens can cause disease, reduce fitness, and shorten lifespans. Moreover, infection rates are increased in bee populations that are stressed by poor nutrition or exposure to pesticides, and thus pathogen prevalence can serve as a broader bioindicator of poor conditions. Given the myriad of factors impacting bumble bees, a comprehensive approach is needed to assess which biotic and abiotic factors are most important for determining the health of bees across diverse landscapes. Through multi-state and multi-year analysis, I examine how environmental conditions affect bumble bee pathogen levels and communities at different spatial scales. First, I assess whether levels of four bumble bee pathogens and distributions of bumble bee species are driven by variation in habitat at a local scale by leveraging the replicated hill and valley system in Central Pennsylvania. I then evaluate if associations between pathogen levels, bumble bee species, and environmental conditions observed in Pennsylvania are also found in North Carolina. In Pennsylvania, I found that different communities of both pathogens and bumble bees were found between forested hills and developed valleys, with viral loads higher in valleys and loads of one pathogen, Crithidia bombi, higher in forests. Valley habitats were dominated by Bombus impatiens, a disturbance resilient bee, while the forest habitats hosted more diverse bumble bee communities. Through DNA barcoding I found that there has been significant misidentification of B. sandersoni as B. vagans or B. perplexus, all of which are found primarily in forested landscapes. The North Carolina data, consistent with data from Pennsylvania as well as other studies in the United States, demonstrate that bumble bee pathogen loads are higher in areas with more honey bees and developed land. However, across the broader datasets, there were variable effects of floral resources and bee community composition on pathogen loads. For example, areas with more floral resources were associated with decreased viral loads in honey bees in North Carolina and in bumble bees in Pennsylvania; but were associated with increased viral loads in North Carolina bumble bees. Moreover, these data show more floral resources support more diverse bumble bee communities, but more diverse communities may facilitate increased loads of some pathogens (e.g., Crithidia) for which some bumble bee species are more susceptible. Ultimately this thesis highlights several outstanding research issues and provides management recommendations. Pathogen transmission and prevalence can clearly be influenced by habitat type but the complexity of landscapes, changing bumble bee communities, and variable susceptibility of different bumble bee species means there is not a single, simple solution to reducing the effects or loads of pathogens for bumble bees. Generally, the presence of honey bees and increased disturbance lead to increased pathogen prevalence. Thus, management efforts should be targeted to improving habitat quality through increased floral and nesting resource quality, which reduces pathogen levels in both honey bees and bumble bees. Higher quality habitat can improve bumble bee community diversity, which can potentially reduce transmission rates, though this depends on the specific species involved. Future studies should focus on species showing declines, to better understand the disease dynamics. While there was partitioning of pathogens at a local scale, the overall loads of pathogens shift over larger regional scales, highlighting the value of examining effects from local to broader landscape scales.
Author: Sarah A. Maxfield-Taylor
Publisher:
ISBN:
Category : Bumblebees
Languages : en
Pages : 112
Get Book Here
Book Description
Bumble bees (Hymenoptera: Apidae) are important native pollinators in wild and agricultural systems, and are one of the few groups of native bees commercially bred for use in the pollination of a range of crops. In recent years, declines in bumble bees have been reported globally. One factor implicated in these declines, believed to affect bumble bee colonies in the wild and during rearing, is natural enemies. A diversity of fungi, protozoa, nematodes, and parasitoids has been reported to affect bumble bees, to varying extents, in different parts of the world. In contrast to reports of decline elsewhere, bumble bees have been thriving in Oregon on the West Coast of the U.S.A. In particular, the agriculturally rich Willamette Valley in the western part of the state appears to be fostering several species. Little is known, however, about the natural enemies of bumble bees in this region. The objectives of this thesis were to: (1) identify pathogens and parasites in (a) bumble bees from the wild, and (b) bumble bees reared in captivity and (2) examine the effects of disease on bee hosts. Bumble bee queens and workers were collected from diverse locations in the Willamette Valley, in spring and summer. Bombus mixtus, Bombus nevadensis, and Bombus vosnesenskii collected from the wild were dissected and examined for pathogens and parasites, and these organisms were identified using morphological and molecular characteristics. Queens of Bombus griseocollis, Bombus nevadensis, and Bombus vosnesenskii were reared in captivity, and those that died or did not initiate nests were also examined for pathogens and parasites. In addition, the immune responses of healthy and infected bees were compared, to examine the effects of a common bumble bee gut pathogen Crithidia bombi (Kinetoplastida: Trypanosomatidae) on its host. This thesis reports that wild bumble bees in western Oregon are infected with the protozoa Apicystis bombi (Neogregarinida: Ophrocystidae) and Crithidia bombi, the fungus/microsporidian Nosema bombi (Microsporidia: Nosematidae), the nematode Sphaerularia bombi (Nematoda: Tylenchida), and two dipteran parasitoids, one unknown and one belonging to the family Conopidae (Diptera: Conopidae). In addition, this research presents the first ever report of infection by the larval pathogen Ascosphaera apis (Ascomycota: Ascosphaerales), in reared bumble bee adults. New host and distribution records are also presented for C. bombi, N. bombi, and S. bombi. The study found that bumble bees infected with C. bombi had lower activated levels of immune responses than healthy bees. The thesis discusses the long-term implications of study findings, and addresses the threat that bumble bee diseases pose to bee pollinators through shared environments.
Author: Nils Cordes
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Several bumble bee species in North America appear to have undergone rapid declines in abundance and distribution. Bombus franklini is probably extinct; B. occidentalis and B. affinis currently are experiencing extensive range reductions; and a shift in the range of B. pensylvanicus indicates a similar trend. In an unprecedented survey, 9,909 specimens of 36 bumble bee species in 38 states were collected and evaluated for presence of pathogens, but I focused on the microsporidium Nosema bombi and its prevalence in two putatively declining species, B. occidentalis and B. pensylvanicus, and four stable species, B. impatiens, B. bimaculatus, B. bifarius and B. vosnesenskii. Crithidia bombi, a protozoan bumble bee pathogen was common in some species, particularly B. mixtus, B. impatiens and B. bimaculatus. It was present in 2.6% of all examined specimens and occurred across most of the United States. Nosema bombi was recovered from 2.9% of all collected specimens. It was present in bumble bee populations in 26 of the surveyed states, predominantly in B. occidentalis (37%) and B. pensylvanicus (15.2%), the species considered to be declining. N. bombi infections occurred in these two hosts in more than 40% of surveyed sites, significantly more than for other hosts. Recovered N. bombi isolates were genetically identical to European strains. The only variation in the pathogen among host species was found in the internal transcribed spacer (ITS) region of the rRNA gene, indicating the presence of multiple alleles and a single nucleotide polymorphism (SNP) that may be unique to North American bumble bee species. Slight variation in infectivity was documented, with only B. occidentalis bees developing infections after oral inoculations. It is still unclear whether N. bombi is contributing to population declines, but correlation of declining species and pathogen prevalence suggest higher susceptibility of these host species. The findings of this thesis support the hypothesis that N. bombi is Holarctic in distribution.
Author: National Research Council
Publisher: National Academies Press
ISBN: 0309102898
Category : Technology & Engineering
Languages : en
Pages : 327
Get Book Here
Book Description
Pollinators-insects, birds, bats, and other animals that carry pollen from the male to the female parts of flowers for plant reproduction-are an essential part of natural and agricultural ecosystems throughout North America. For example, most fruit, vegetable, and seed crops and some crops that provide fiber, drugs, and fuel depend on animals for pollination. This report provides evidence for the decline of some pollinator species in North America, including America's most important managed pollinator, the honey bee, as well as some butterflies, bats, and hummingbirds. For most managed and wild pollinator species, however, population trends have not been assessed because populations have not been monitored over time. In addition, for wild species with demonstrated declines, it is often difficult to determine the causes or consequences of their decline. This report outlines priorities for research and monitoring that are needed to improve information on the status of pollinators and establishes a framework for conservation and restoration of pollinator species and communities.
Author: Kayla Mundy-Heisz
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Bumblebees (Bombus spp.) pollinate a variety of wild floras and agricultural crops. However, some species are in decline due to a variety of interacting stressors: climate change, habitat loss and degradation, parasites and disease, and pesticides. Pesticides, particularly the neonicotinoids, a group of systemic insecticides, have been implicated in declines of European bumblebee species, but the effects of systemic insecticides are less clear for many North American species. One aim of this thesis was to determine the relative acute oral toxicity of systemic insecticides on Bombus impatiens (Cresson, 1863) workers in comparison to honey bee workers (Apis mellifera Linnaeus, 1758). Thiamethoxam was observed to be the most acutely toxic, followed by sulfoxaflor, flupyradifurone, and cyantraniliprole. A secondary aim was to determine if thiamethoxam fed to wild B. impatiens and Bombus bimaculatus (Cresson, 1864) queens for 14 days would result in any changes in the queen's ability to establish and maintain a colony for reproduction. However, many queens died during the experiment, preventing statistical analysis of the surviving colonies' outputs. In an ancillary aim to record parasite prevalence in queens, conopid larva and tracheal mites were not as commonly detected as nematodes and external mites. A third aim was to determine the usage of conventionally managed farm field margins by bumblebee queens. More bumblebee queens were observed foraging in farm field margins than in the paired natural areas, although more bumblebee queens were observed nest searching in the natural areas. A fourth aim was to compare the bumblebee species captured with different sampling techniques. Active (targeted netting) and passive (Blue Vane Traps, BVTs) sampling were completed in conventionally managed farms and paired natural areas. There were no differences in species richness caught between the two sampling techniques, however, when comparing sampling technique and site combinations, significantly greater species richness was found in passively sampled natural areas. In contrast, a significantly greater abundance of bumblebees was caught with active sampling in natural areas than in farms, but there was no difference between the sties when sampling with BVTs.
Author: George LoCascio
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Declines in several pollinator species are due to a variety of factors, including pathogens. Incorporating pollinator-friendly plant species into wild and agricultural habitats could reduce the stress of pathogens if food sources act medicinally against pathogens. Previous research demonstrated one domesticated sunflower cultivar (Helianthus annuus) can dramatically reduce a gut pathogen (Crithidia bombi) of the common eastern bumble bee, Bombus impatiens. To ascertain the breadth of this medicinal trait, we tested whether pollen from several H. annuus cultivars and four relatives could also reduce C. bombi infections in B. impatiens. We also investigated whether timing of exposure to sunflower pollen relative to time of infection affected the strength of this medicinal trait. In all experiments, bees were infected and then fed their respective pollen diets for a week before they were dissected to assess infection. In our first experiment, all pollen from Helianthus species and relatives reduced C. bombi cell counts compared to our single species control of buckwheat (Fagopyrum esculentum). In our timing of exposure experiments, a one-time exposure to sunflower pollen present at the time of infection did not lower infection levels. In longer exposure trials, sunflower pollen suppressed C. bombi infection with a strength inversely proportional to the time between treatment and infection. Our results suggest that medicinal pollen may be widespread in the Helianthus genus and potentially throughout the Asteraceae family. Thus, these results provide insights into how strategic plantings of certain floral resources can help mediate and influences pollinator disease dynamics.
Author: California. Department of Food and Agriculture
Publisher:
ISBN:
Category : Bumblebees
Languages : en
Pages : 37
Get Book Here
Book Description
Author: Rehanon Pampell
Publisher:
ISBN:
Category : Bumblebees
Languages : en
Pages : 124
Get Book Here
Book Description
"Major world pollinators include bees, beetles, flies, butterflies, birds and bats, all of which help pollinate over 75% of Earth's flowering plant species and nearly 75% of the crops. In arctic and subarctic regions, bumble bees are considered important pollinators; however, immediate concerns involving climate change, colony collapse disorders in honey bees, and lack of faunistic insect studies in Alaska emphasize the need to study bumble bees in interior Alaska. Seventeen species of bumble bees were identified from three localities: Delta Junction, Fairbanks, and Palmer, Alaska. Not all species were recovered from all localities and species richness and relative abundance varied by years. Delta Junction displayed the highest relative bumble bee abundance representing approximately 50% of the overall total of bumble bees collected during the two year study. Overall, the most common bumble bees near agricultural lands were B. centralis, B. frigidus, B. jonellus, B. melanopygus, B. mixtus, and B. occidentalis. Their populations and local diversity were highly variable from year to year. A species believed to be in decline in the Pacific North West states, B. occidentalis, was collected in relative abundance up to 13.5%; this species was collected from the three sites studied. Preliminary data indicates that bumble bees were found to be infected by Nosema and nematodes with infection rates up to 12.5% and 16.7% for Nosema and nematodes respectively. Of the eight species infected by parasites, B. occidentalis displayed the highest Nosema infection, while B. centralis was the species with the highest infection of nematodes"--Leaf iii.
Author: Lynn V. Dicks
Publisher: Pelagic Publishing
ISBN: 1907807020
Category : Nature
Languages : en
Pages : 147
Get Book Here
Book Description
This book brings together scientific evidence and experience relevant to the practical conservation of wild bees. The authors worked with an international group of bee experts and conservationists to develop a global list of interventions that could benefit wild bees. They range from protecting natural habitat to controlling disease in commercial bumblebee colonies. For each intervention, the book summarises studies captured by the Conservation Evidence project, where that intervention has been tested and its effects on bees quantified. The result is a thorough guide to what is known, or not known, about the effectiveness of bee conservation actions throughout the world. Bee Conservation is the first in a series of synopses that will cover different species groups and habitats, gradually building into a comprehensive summary of evidence on the effects of conservation interventions for all biodiversity throughout the world. By making evidence accessible in this way, we hope to enable a change in the practice of conservation, so it can become more evidence-based. We also aim to highlight where there are gaps in knowledge. Evidence from all around the world is included. If there appears to be a bias towards evidence from northern European or North American temperate environments, this reflects a current bias in the published research that is available to us. Conservation interventions are grouped primarily according to the relevant direct threats, as defined in the International Union for the Conservation of Nature (IUCN)’s Unified Classification of Direct Threats.
