Brassicas, leafy salads, oilseed rape and legumes: Developing and evaluating management strategies to mitigate woodpigeon Columba palumbus damage to crops

The Problem:

The current proposal takes forward the findings of the APHA (2014) review (FV426: A review of the woodpigeon costs to brassicas, salad crops and oilseed rape and the effectiveness of management activities) in order to address key gaps in practical woodpigeon management to mitigate crop damage. The proposed study will develop and evaluate different control measures to reduce woodpigeon grazing activity, and by association crop damage, to acceptable levels and provide growers with best practice advice.

The project will involve a number of elements:

• Field evaluation of selected traditional deterrents deployed in an integrated manner based on findings from APHA (2014). Trials will evaluate the practicality, effectiveness and cost of deployment in one study area of OSR and one study area of horticultural brassicas and salad.
• The field trials will include evaluation of novel techniques previously shown to have potential as woodpigeon deterrents.
• The findings of the field trials will inform the development of improved best practice guidelines, utilising traditional and novel techniques, based on optimising resource and labour input and deterrent effect.
• Population control at a landscape level involving coordinated shooting over a delineated area (e.g. 10km square) during Spring/early Summer.
• Monitoring of woodpigeon movements and habitat use at the level of the flock to investigate changes in movement patterns and habitat use by woodpigeons in response to non-lethal and lethal control.
• Preliminary investigation of capturing and tagging woodpigeons in order to investigate changes in movement patterns and habitat use by individual woodpigeons in response to non-lethal and lethal control.
• Preliminary investigation of drones for surveying, monitoring and deterring grazing woodpigeons.
• Liaison with relevant stakeholders, including Horticultural Development Council (HDC), Home Grown Cereals Authority (HGCA), crop associations – Leafy Salad Growers, Brassica Growers Association, Processed Vegetable Growers Association, National Farmers Union (NFU), British Association of Shooting and Conservation (BASC).

• The benefits for stakeholders will be fully realised from one further step, which is outwith the scope of this project: Facilitation of future knowledge transfer to relevant stakeholders via a range of fora such as workshops and crop association conferences.

Benefits to industry

From a successful outcome, growers could benefit from improved best-practice guidance as a consequence of:

• Improved yield and uniformity of maturity at harvest, currently lost due to reduced photosynthetic leaf area suffered through grazing during the early stages of growth of OSR, peas, horticultural brassicas and salads.
• Reduction in wastage - mature brassica and salad crops grazed by woodpigeons result in loss of marketable crop (out of specification) and costly input materials to produce the wasted crop.
• Reduced labour and capital costs managing deterrents more effectively.
• Fewer complaints from retailers and consumers concerning damaged produce.
• Potentially less microbial contamination of the finished product from woodpigeon faecal soiling.

The results of the project will be delivered back to the growers via a range of fora such as workshops and crop association conferences (outwith the current proposal). The findings will also be written into a best practice document for circulation amongst growers (outwith the current proposal). It is anticipated that at least one publication in a scientific research journal will be produced that will facilitate dissemination to the wider scientific and industry communities.

Aims and objectives:

1. Project aim(s):

The overarching project aims are:

• To develop and evaluate the effectiveness of management measures to mitigate the impact of woodpigeon damage to horticultural brassicas, leafy salads, oilseed rape and legumes.

2. Project objective(s):

• To undertake field trials to evaluate the effectiveness of deterrents deployed in an integrated management strategy (IMS) on the crops of interest. The techniques and approaches to be evaluated will include those that have been identified in a previous Animal and Plant Health Agency (APHA) review of management options (Parrott et al. 2014: FV426).

• To undertake an evaluation of population management, using shooting, to reduce woodpigeon grazing activity.
• To undertake preliminary investigations of woodpigeon capture and tagging/marking and its potential for monitoring woodpigeon movements and habitat use in response to crop protection measures.
• To undertake preliminary evaluation of the potential for the application of unmanned aerial vehicles (drones) in the monitoring and management of woodpigeon grazing activity.