Lek counts are a tool used to monitor capercaillie numbers in Scotland and have been carried out consistently across their range since 2002. This involves licensed surveyors counting the number of males that attend known leks, which is coordinated by the Capercaillie Advisory Officer and funded by the Cairngorms Capercaillie Project, Forestry and Land Scotland, NatureScot and the RSPB.
As capercaillie are a legally protected species, under the Wildlife and Countryside Act (1981), these lek surveys are completed under a Schedule 1 license from NatureScot. Surveyors are fully trained and follow strict protocol to gather accurate data and reduce the risk of disturbance.
Lek locations can move, so they are often ‘cold-searched’, which involves surveyors checking potential lek sites for signs of capercaillie during a daytime walk-through, to identify hotspots of activity. These are followed up by early morning lek counts (start from 4am), which take place in April/early May, and primarily involve surveyors counting males seen from hides, which they enter and sleep in the night before, to reduce disturbance. The number of visits to a lek are limited to reduce potential disturbance and are generally only counted once on an annual basis.
These results provide an insight into population trends and inform local management for capercaillie. These counts are not intended to provide an overall population estimate for capercaillie as it is only a partial dataset e.g., female capercaillie can be missed as they don’t attend leks every morning and not all males attend leks (e.g., juvenile males will be missed).
The national survey, which has been repeated every 6 years since the early 90’s surveys capercaillie across their range, so the results are used to inform populations estimates. The 2021/22 national survey estimated that there are now only 542 capercaillie in Scotland.
There was an overall decline of 31 lekking males in 2021, compared to 2019 data. There was a decline in total number of birds in Strathspey and Deeside/Donside, with an increase of 1 bird in Easter Ross and Moray / Nairnshire and Perthshire remaining the same as 2019.
There was an overall decline of leks occupied, with 15 fewer lek sites occupied compared to 2019 data. Strathspey had 9 fewer leks occupied this year, Easter Ross had 4 fewer leks occupied, Deeside / Donside had 2 fewer leks and Moray / Nairnshire and Perthshire remained the same as 2019.
The weather was favourable (mostly dry & still) for the majority of these lek counts. However, there was a break in the weather after the 25th of April, with rain and snow on most days, which may have impacted the few counts completed between the 26-30th of April.
These lek counts demonstrate that there has been a consistent decline in lekking birds between 2015 (which was the highest total count during this period) and 2021. There is more fluctuation in leks occupied, but 2021 had the lowest number of leks occupied during this time period. Strathspey remains the stronghold for these birds, but numbers have also consistently declined since 2016, rather than remaining stable, and the other populations remain at low numbers.
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