Details of Award
NERC Reference : NE/K007106/1
[AGRIFOOD] Are neonicotinoid seed dressings used on arable crops impacting on non-target herbivorous insects in arable field margins?
Training Grant Award
- Lead Supervisor:
- Professor D Goulson, University of Sussex, Sch of Life Sciences
- Grant held at:
- University of Sussex, Sch of Life Sciences
- Science Area:
- Terrestrial
- Overall Classification:
- Terrestrial
- ENRIs:
- Biodiversity
- Environmental Risks and Hazards
- Science Topics:
- None
- Abstract:
- Neonicotinoid insecticides are currently the most widely used insecticides globally, with 1.3 million hectares of arable crops treated in the UK in 2010. They are systemic insecticides, generally applied as a seed dressing, with the active ingredient being absorbed by the growing plant and providing protection against insect herbivores. Recent studies have demonstrated that the low concentrations of neonicotinoids which transfer to the nectar and pollen of treated flowering crops such as oilseed rape can have substantial negative effects on bees. Here we propose to examine whether the environmental impacts of neonicotinoids on non-target organisms extend beyond bees. Recent research has demonstrated that ~98% of the active ingredient does not go in to the crop. Some is released as dust during seed drilling, and much goes into soil water where it can persist for long periods. Levels of neonicotinoid sufficient to kill herbivorous insects have been detected in dandelions growing in field margins. We hypothesize that neonicotinoids may be having a hitherto unrecognized impact on a range of non-target herbivorous insects in farmland, with knock on effects for predatory species such as insectivorous birds. To evaluate this, we will address the major knowledge gaps: 1. Establish the levels of neonicotinoids in field margin/ hedgerow vegetation in UK farmland. This requires replicated sampling of a range of non-target plant species growing in field margins adjacent to seed-treated crops plus controls, with screening of samples for neonicotinoids. Plants to be sampled will span both woody and herbaceous species. Fieldwork will focus on (a) the RSPB's Hope Farm - an arable farm in Cambridgeshire offering a range of hedgerow and field margin managements and detailed field-by-field data on cropping histories and agrochemical treatments and (b) an RSPB nature reserve adjacent to seed-treated crops, to assess whether neonicotinoids are also impacting on high biodiversity value land. 2. The student will conduct bioassays to determine whether concentrations of neonicotinoids found in (1) are adequate to induce mortality or significant sublethal effects in a selection of insect herbivores. This will focus in part on insect groups known to be important in the diet of declining farmland birds (Wilson et al 1999); namely rasshoppers, leaf-beetles, weevils, Lepidoptera (adults and larvae) and tipulids (adults and larvae). 3. Studies on bees suggest that exposure to field-realistic levels of neonicotinoids can have significant sublethal impacts on behaviour, notably impaired foraging and navigation. The student will develop behavioural assays for Lepidoptera to quantify impacts upon both larvae and adults, including assaying the ability of adults to learn associations with food rewards. 4. Direct evidence of sub-lethal neonicotinoid impacts on birds is absent, but one declining species - the Linnet - depends heavily on ripening rape seed as a nestling food sources. Long-term declines stabilised in the late 1980s as oilseed rape acreages increased but have declined again since the mid-1990s, especially in England where neonicotinoid usage is most prevalent. RSPB holds a large and detailed nest success and nestling diet database for Linnets in Oxfordshire collected in the 1990s. The student will revisit the same study areas to collect a comparative data set and test (a) whether nest success levels are reduced compared with the mid-1990s, (b) whether rape and dandelion seeds fed to chicks contain neonicotinoids, (c) whether nesting survival and condition is correlated with prevalence of neonicotinoids in the seeds in nestling diet. 5. We will use data from the UK Breeding Birds Survey to determine the temporal and spatial associations between neonicotinoid usage, and the regional population trends of those farmland birds likely to be sensitive to them.
- NERC Reference:
- NE/K007106/1
- Grant Stage:
- Completed
- Scheme:
- DTG - directed
- Grant Status:
- Closed
- Programme:
- Open CASE
This training grant award has a total value of £73,198
FDAB - Financial Details (Award breakdown by headings)
| Total - Fees | Total - RTSG | Total - Student Stipend |
|---|---|---|
| £13,978 | £10,026 | £49,194 |
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