A new report has shown that landowners in Co. Wicklow, which has the highest deer population density in Ireland, face significant agricultural and economic losses due to deer grazing.
The Wicklow Deer Management Project found that the differences in grass yields where deer had been grazing compared to where they had been excluded ranged between 10% and 35%.
Through a series of grassland measurements, the report found that a 30% loss of yield due to deer grazing could see a loss of production costs of €180/ac or €445/ha.
However, this loss is a very modest estimate towards potential losses as a result of the grazing impact, the Wicklow Uplands Council which managed the three-year project said.
Grass cages to exclude grazing deer access to the grass growing within the cage were deployed over a 10-12 week period in fields of spring saved grass for silage production.
To determine economic loss, the council looked at the land value as the rental value assigned to a 1st cut of silage and estimated that the 1st cut produces around 45% of yearly production.
TB in deer
A TB testing pilot in conjunction with the Department of Agriculture, Food and the Marine’s (DAFM) veterinary section was also carried out.
To assess the usefulness of hunter-level surveillance in identifying high TB prevalence locations in deer, hunters submitted samples from deer that they considered may have TB for analysis.
Report findings show that TB was found in over 16% of the suspicious deer samples, all of which were found in an area of west Wicklow.
Stating that the western part of the county is currently identified as a “TB blackspot in cattle”, the Wicklow Uplands Council noted that:
“It is important to highlight that these results do not represent a prevalence of TB but are rather an indication of a diagnostic rate at hunter level, as it was suspicious samples that were tested.
“Nevertheless, the findings did, for the first time, prove a presence of TB in deer in west Wicklow and identified hotspot locations that merit further follow up for disease control.”
Since the project began in 2018, five Deer Management Units (DMU), in which landowners and hunters manage deer in a sustainable manner, were established across the county.
A number of key recommendations were produced based on the findings of the project, including:
- Management plans should focus on reducing the adverse impacts associated with deer;
- Increased culling of female deer is required;
- Further detailed analysis of economic loss to grassland and forestry is required;
- All landowners need to consider the leasing of hunting carefully as they have responsibility for ensuring that hunters are operating effectively;
- The TB testing pilot identified TB hotspots in west Wicklow and warrant much further detailed investigation;
- Venison needs to be promoted as a sustainable healthy product;
- The National Deer Management Forum should be reformed as a matter of urgency.
The project was funded by the DAFM, and the Department of Housing, Local Government and Heritage, and managed jointly by the Wicklow Uplands Council and the Wicklow Deer Management Partnership.