Lek counts are a tool used to monitor capercaillie numbers in Scotland and have been carried out consistently across the capercaillie range since 2002, with the exception of 2020 due to Covid restrictions. Lek surveys involve licensed surveyors counting the number of male birds that attend known leks. The surveys are coordinated by the Capercaillie Advisory Officer and funded by the Cairngorms Capercaillie Project, NatureScot and the RSPB.
As capercaillie are a protected species under the Wildlife and Countryside Act (1981), all lek counts are completed under a Schedule 1 license from NatureScot. Surveyors are trained and follow strict protocol to gather accurate data and reduce the risk of disturbing the birds.
Lek locations can move, so they are often ‘cold-searched’ in advance. This involves surveyors checking sites for signs of capercaillie during the daytime to identify hotspots of activity. These surveys are followed up by early morning lek counts which start at dawn and take place during April and early May. The counts primarily involve surveyors counting male birds seen from hides, which surveyors enter the night before and sleep in to reduce disturbance. The number of visits to a lek are also limited to reduce potential disturbance and generally leks are only counted once each spring.
The results from the counts provide an insight into population trends and inform local management for capercaillie. The counts are not intended to provide an overall population estimate for capercaillie as it is only a partial dataset. For example, female capercaillie can be missed as they do not attend leks every morning and young males do not attend leks until they are ready to breed.
The national survey, which has been repeated every 6 years since the early 1990s involves surveyors walking multiple transects across the capercaillie range during the winter. As the whole capercaillie range is surveyed through this process, the results can be used to inform population estimates.
The latest national survey in 2021/22, carried out by the RSPB and part-funded by the Cairngorms Capercaillie Project, estimated that there are now only 542 capercaillie in Scotland. 542 birds is the lowest recorded level since the start of the national survey in 1992 – 1994; 51% lower than the 2015/16 estimate; and 85% of the Scottish capercaillie population now lives in the Cairngorms National Park.
Key results from the 2023 lek counts
There was an increase of 19 lekking males in 2023 compared to 2022, with a total of 168 lekking males counted. This was due to an increase in the Strathspey and Easter Ross populations, whilst Deeside remained the same as 2022 and Perthshire and Moray / Nairnshire both declined by 1 bird respectively.
There was an increase in leks occupied, with 6 more occupied compared to 2022. Again, this was due to an increase in leks occupied in Strathspey and Easter Ross, whilst Deeside remained the same as 2022 and Perthshire and Moray / Nairnshire both declined by 1 lek respectively.
The survey effort remained consistent.
The weather was mostly favourable in early April, with more rain and colder temperatures in late April and early May.
2023 is the first year since 2015 that there has been an increase in the total number of lekking males recorded in Scotland. The total number has been declining since 2015, with the exception of 2021 and 2022, where the number of males remained the same.
Strathspey remains the stronghold for capercaillie in Scotland and the periphery populations remain in a perilous position, with low numbers of males consistently being recorded. Whilst an increase was recorded in both the number of males and number of leks occupied in Easter Ross, the lowest count to date for the Moray / Nairnshire population was reported, with only 1 male being recorded.
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