Use this URL to cite or link to this record in EThOS:
Title: The effects of extremely low frequency electromagnetic fields on insects
Author: Shepherd, Sebastian James
ISNI:       0000 0004 7234 3002
Awarding Body: University of Southampton
Current Institution: University of Southampton
Date of Award: 2018
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
Flying insect species are currently in decline, including many species that provide important pollination ecosystem services. Combined exposure to various environmental stressors are associated with insect declines, including land-use change, pesticide use and climate change, but the potential biological and environmental effects of extremely low frequency electromagnetic fields (ELF EMFs) are poorly understood. ELF EMFs are pervasive in the environment, and anthropogenic ELF EMF pollution has increased greatly in recent years. Despite this, little has been done to consider the potential environmental impacts of ELF EMFs. Given that there is evidence that ELF EMFs can have biological effects, it is important to explore these biological stimuli and their potential to affect insects in the environment. Here the biological effects of ELF EMFs on important insect species were investigated, with two-fold aims of both increasing understanding of the biological effects of ELF EMFs, and determining whether field-realisitc levels of ELF EMFs have the potential to cause envrionemental stress to insects. ELF EMF impacts were investigated with the desert locust, as an economically important agricultural pest and a species that provides utility in understanding insect neurophysiology, and the honey bee, as a globally important pollinator and a well known study species for insect cognitive behaviour. Short-term exposure to high levels of ELF EMFs was found to affect neurophysiology, and reduce locomotory function in locusts, as well as increase stress protein levels in bees and locusts, and affect honey bee cognitive behaviour. Acute exposure to ELF EMFs at levels that can be encountered regularly in the environment around man-man sources for ELF EMFs reduced honey bee performance in olfactory learning assays, affected flight behaviour, and affected feeding and flight performance in a semi-field scenario. Further to this, some of these impacts of ELF EMFs on cognitive behaviour and flight were reduced when ELF EMFs were applied in combination with other well-known environmental stressors, neonicotinoid insecticides. These findings give a more detailed indication of some of the physiological effects that may underpin changes in insect locomotory behaviour that occur after short-term exposure. This is the first time that powerline simulating ELF EMFs have been directly measured and applied to insects in the context of considering the ecological effects (and thus using field-realistic exposure levels) of the ELF EMFs, rather than just the biological effects. This is the first indication that short-term and acute ELF EMF exposure can affect insect cognitive behaviour, and these effects have been shown to occur at levels which can be encountered in the field by a globally important pollinator species, the honey bee. This is also the first indication that acute field-realistic ELF EMF exposure can affect insect locomotory behaviour in the environement. This research describes new effects of ELF EMFs on insect biology and establishes that ELF EMFs have a potential to affect insect ecology, such that future ELF EMF understanding must be focused in further exploring mechanisms by with ELF EMFs cause biological effects, as well as the larger scale ecological risk assessment of ELF EMF impacts from powerlines.
Supervisor: Newland, Philip ; Jackson, Christopher Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available