A long-term monitoring network to underpin deer management in Scotland: a pilot study

• Between 60,000 and 70,000 red deer are culled across Scotland annually.
• In partnership with deer managers in both the private and public sector, we have set up a long-term monitoring network which will provide data on deer performance and health.
• This will enable us to investigate the spatio-temporal response of deer to environmental change
• Results are channelled to deer managers and policy makers via web sites and bulletin boards so that evidence based, locally specific, sustainable deer management strategies can be developed.

Some provisional analyses are summarised here.

Assessing the accuracy of estimating the age of deer in Scottish larders

Quantifying the age-specific spatial and temporal variation in body mass and reproductive status is essential if we are to detect the response of populations to environmental change.

• Accurate ageing requires detailed laboratory techniques which are impractical for management.
• Managers rely on assessing age on the pattern of tooth eruption and wear.

Initial results indicate that:

• Age estimation by stalkers and rangers was good overall:
  • 34% of samples estimated by stalkers were in agreement with the laboratory age with 31% within +/- 1 year and 16% within +/- 2 years.
• Managers tended to overestimate the age of the samples:
  • 49% of the samples overestimated
  • but only 18% underestimated.
• There were no mistakes when estimating the age of calves,
  • 11% of the yearlings were wrongly aged as calves or 2 years old.
  • 30% of 2 year olds were wrongly aged as yearlings or as 3 or 4 years old.

These findings clearly indicate the need to establish a consistent protocol of age estimation across larders, together with a training programme so that the accuracy of the age is as reliable and consistent across Scotland.

What is driving the reproductive condition of deer hinds?

• The reproductive status of animals is one of the most valuable indices to estimate the condition and performance of wild mammals.
• We have analysed the ovaries from culled female deer to quantify their age-specific reproductive status.
• The analysis indicates that in both moorland and woodland populations, no calves were pregnant.
• Around 20% of the yearlings and 85% 2 year old were pregnant and pregnancy rates started to decline from age 6 onwards.
• Hinds from moorland areas had consistently lower pregnancy rates than those from woodland which reflects the lower body mass in these populations.

Contact: Dr. Javier Perez Barberia