Lek Report for 2004
Sandra Maclean,
Black Grouse Recovery Project Officer
9 Achnamara
Lochgilphead
Argyll
PA31 8PU
The Project is funded by a partnership of Scottish Natural Heritage, Forestry Commission Scotland, RSPB Scotland, Scottish Power and an award from the Esmée Fairbairn Foundation.
Survey Coverage and Methodology
1. Survey work in 2004 was extended from the 2002 & 2003 survey area into Oban & Lorne, north-east Mid Argyll, north Helensburgh & Lomond, and north Cowal (Map 1).
2. A total of 127 leks were surveyed in 2004.
3. With the exception of just seven, all leks which held lekking males in the last year in which they were surveyed (2002 or 2003), were resurveyed in 2004.
4. All 2003 Core Area Priority 1and 2 sites were surveyed in 2004.
Re-survey of most of the 2002 & 2003 leks was achieved with the help of West Argyll and Cowal & the Trossachs Forest District rangers, Loch Lomond & the Trossachs National Park Rangers, John Simpson of the MOD Police, members of the Project’s steering and working group and volunteer surveyors.
In 2004 the Project Officer’s target survey area stretched from Strachur and Glen Douglas, north to Glen Orchy and Loch Awe, and west to Balliemenoch and Dalchenna (Map1). Out-with the target survey area, several additional leks were surveyed and areas searched in south Cowal and Mid Argyll. John Simpson of the MOD police surveyed the Helensburgh & Lomond area as far north as Glen Douglas. Ian Hopkins surveyed north Bute.
The Argyll and Bute Black Grouse Project financed a short contract in Lorne undertaken by Tony Millard who surveyed the area from Loch Etive and the Pass of Brander in the north, south to Loch Trallaig and east to Loch Awe (Map1).
The Project was awarded a Community for Biodiversity Grant to finance a contractor to organise and work alongside volunteer lek surveyors. The contract was undertaken by Cristina McAvoy and allowed the Project to achieve a far higher level of community participation in lek surveying than in 2002 or 2003. In addition to the volunteer surveyors that Cristina McAvoy worked with directly on the ground, a further 26 lek survey volunteers were contacted across Argyll and sent the information required to undertake a lek survey in their locality. Most volunteers were asked to re-survey leks which held birds in 2002 or 2003. More experienced surveyors were given new areas to cold search for additional leks.
The methodology used was taken from instructions for the 1995-96 national sample survey (Hancock, M. et al 1999). The maximum number of males attending a lek was recorded between the period of an hour before and an hour after dawn. In 2002-2003 males lekking more than 200m apart were recorded as separate leks. From 2004, single birds lekking within 500m of a previously known lek, were recorded as one lek. Sightings of solo males in the dawn period but which did not display were not included. Where time allowed, repeat visits were made to each lek site, one in the first half of the lek season and one in the second. Where it was possible, several surveyors visited an area, which held several lek sites on the same morning to eliminate the possibility of double counting. However, in practice a single surveyor made most visits.
The Project Officer continued surveying and searching for additional lek sites until 31 May. Three leks were recorded after the main survey period, in the second half of May. These are included in the figures below. It is intended that these will be revisited in 2005. Casual records of lekking males, which were not made according to the above methodology, were accepted for five leks where they provided the highest count for those leks and were not considered to be duplicate records.
Results 2004
The number of lekking male black grouse at all 127 leks surveyed in 2004 is given, area by area, in Appendix 1. The information is tabulated to show the variation in counts at each individual lek for the years 2002-04.
The downward trend found at leks in 2002 and 2003 was repeated at leks surveyed in 2003 and 2004, however, the rate of decline appears to have been a little less severe. Information from the leks surveyed in 2002 and 2003 indicated a 15% decline between the two years. Information from the leks surveyed in 2003 and 2004 indicated a 10% decline between the two years (Table 3). The decline between 2003 and 2004 was restricted to Mid Argyll, Kintyre and Cowal, with numbers of lekking males stable on Bute, showing a slight increase in Oban & Lorne and a major increase in the Helensburgh & Lomond Area. Most notably one lek in the Helensburgh & Lomond Area increased from one lekking male in 2003 to ten males in 2004. Such a major increase is not mirrored elsewhere at leks in Argyll and is difficult to explain. A contributory factor could have been the dry June in 2003 resulting in a good breeding season and chick survival but, given that this good weather in 2003 was enjoyed across Argyll this cannot be the whole story. Where increases in the number of males at leks between 2003 and 2004 were evident in other areas of Argyll, they were very modest. Small increases were evident at several leks in Kintyre, Knapdale, and Cowal. Two new leks holding a total of six lekking males were also located in Kintyre in 2004. The apparent steep decline on Forest Commission Scotland ground within West Argyll Forest District may perhaps be partly due to forestry operations shifting leks to new, and as yet unidentified, locations (Table 2). In West Knapdale, West Argyll Forest District, up to ten birds were recorded in February in the vicinity of the 2003 lek site. However during survey work in April and May 2004, only one displaying male was sighted.
The large increase in the total number of lekking males in 2004 in the Oban & Lorne area is due to the extension of survey to new areas (Table 1).
Maps 2, 3 and 4 show the general distribution of leks in the three survey years but the numbers of lekking males for each lek have been omitted in order to protect the confidences and rights of private landowners. The largest leks in Argyll in 2002 and 2003 years held 7 males. The largest lek in 2004 held 10 males. The average lek size in all three survey years remained below 2 males.
Table 1. Totals of lekking males recorded in Argyll in 2002, 2003 & 2004.
2002 / 2003 / 2004Kintyre / 36 / 26 / 28
Knapdale / 25 / 19 / 12
Mid Argyll (north of Crinan) / 11 / 10 / 11
Mid Argyll & Kintyre Total / 72 / 55 / 51
Oban & Lorne / 11 / 9 / 50**
Bute & Cowal / * / 35 / 29
Helensburgh & Lomond / * / 19 / 36
Total for area surveyed in that year
/ 83 /118
/ 166* No counts available
** Extension of survey coverage
Table 2. Totals of lekking males recorded on Forestry Commission Scotland ground 2002, 2003 & 2004.
Summary / 2002 / 2003 / 2004Kintyre / 13 / 8 / 4
Knapdale / 15 / 11 / 4
Mid Argyll (north of Crinan) / 9 / 4 / 0
West Argyll Forest District Total / 37 / 23 / 8
Lorne Forest District / * / 0 / 3
Cowal & Trossachs Forest District / * / 5 / 3
Total / 37 / 28 / 14
* No counts available
Table 3. Totals of lekking males at leks surveyed in 2003 and 2004 and percentage change between the two years.
Summary / 2003 / 2004 / Percentage changeMid Argyll & Kintyre / 55 / 35 / -36%
Oban &Lorne / 9 / 10 / +11%
Helensburgh & Lomond / 18 / 32 / +78%
Cowal / 24 / 18 / -25%
Bute / 4 / 4 / 0
Total / 110 / 99 / -10%
Summary
Survey work in Argyll 2002-2004 provided further evidence of the serious and continuing decline in the Scottish black grouse population. The Argyll black grouse population has reduced to a serious level and requires urgent conservation action and adequate funding to carry out remedial work.
Whilst a full analysis of habitat preferences has still to be carried out, the majority of leks in 2002 and 2003 in Argyll appeared to be associated with forestry habitats. Whilst this observation held true for most of Argyll in 2004, several leks in the Oban area and the Helensburgh & Lomond area did not show such close association with forestry in 2004.
The Argyll Population in Context
On the basis of current survey knowledge the populations of black grouse to the north of the Argyll boundary, in Morvern and south Lochaber, are modest and unlikely to be a source for immigration to supplement numbers on mainland Argyll. A partial survey in south Morvern in 2003 recorded a total of 10 lekking males at 5 leks. In the west, on the Argyll Islands, black grouse are currently reported only from Islay and Jura. Both island populations appear to be at very low levels and it is unlikely that either island holds more than a few males. To the east of Argyll reasonable populations of lekking males were recorded in 2004 within a few kilometres of Loch Lomond. An exchange of birds between Central Scotland and the Argyll population seems feasible given the distance between lek sites. Lek survey work in Central Scotland 1999-2004 indicated a continued contraction in black grouse range and numbers in that area.
Future Survey Work
The majority of Argyll has been surveyed for lekking males in 2002-2004. North Lorne, Islay and Jura have yet to be surveyed and these areas remain the main focus for the 2005 survey season along with the Core Area sites identified in 2003 and 2004 (Map1). It is hoped that a re-survey of many of the leks identified in 2002-2004 will be possible through a combination of Forest Commission Scotland & National Park rangers, steering and working group members and volunteer surveyors.
Acknowledgements
The following people are thanked for their contribution to survey work: John McAvoy, Fiona Macarthur, John Armitage, Gordon Bishop, Roger Broad, Tom Callan, Rhona Campbell, Marina & Geoff Cowham, Catriona McColl, Donald Macgregor, John Halliday, Malcolm Holder, Ian Hopkins, Paul Kent, Anton Locket, Gus Lennox, Stewart Marshall, Jane Mitchell, George Newall, Pam Johnson, Robert Macpherson, Ian Potts, Ross Preston, Saya Sheridan, John Simpson, Jolyon Small, Blair Urqhuart, Dave Walker, Thomas Wilson, Roger Wright, Fergus Younger, West Argyll Forest District Rangers, Cowal & Trossachs Forest District Rangers, Lorne Forest District Rangers, Loch Lomond and the Trossachs National Park Rangers.
The Project was initiated following the establishment of the Argyll & Bute Biodiversity Partnership and the launch of the Argyll Local Biodiversity Action Plan to address the plight of Black Grouse in Argyll. It is funded by a partnership of Scottish Natural Heritage, Forestry Commission, RSPB Scotland, Scottish Power and an award from the Esmée Fairbairn Foundation.
Survey work in 2004 was supported by a Community for Biodiversity Award from the Argyll & Bute Council.
References
Hancock, M. Baines, D. Gibbons, D. Etheridge, B. & Shepherd, M. (1999) Status of male black grouse (Tetrao tetrix) in Britain 1995-96. Bird Study, 46, 1-15
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Appendix 1 Number of black grouse males at leks 2002, 2003 & 20042002 / 2003 / 2004
Kintyre: Private
* / * / 2
* / * / 4
1 / 2 / 0
2 / 0 / 0
5 / 3 / 4
7 / 4 / 4
* / 1 / 1
4 / * / 3
0 / 2 / 0
1 / * / *
1 / 1 / 1
1 / 1 / 1
1 / 2 / 4
0 / 2 / 0
Kintyre: Forestry Commission Scotland
2 / 0 / *
1 / 0 / *
1 / 1 / 0
* / * / 1
0 / 2 / 0
2 / 1 / 0
1 / 0 / 0
0 / 1 / 0
1 / 1 / 0
0 / 0 / 3
36 / 26 / 28 /
Kintyre total
Knapdale: Forestry Commission Scotland
0 / 2 / 12 / 0 / 0
3 / 2 / 1
0 / 0 / 1
10** / 7 / 1
**lekking males moving between several FCS lek sites 2002
Knapdale: Private
2 / 1 / 25 / 5 / 4
0 / 1 / 0
3 / 1 / 1
0 / 0 / 1
15 / 19 / 12 /
Knapdale total
8
2002 / 2003 / 2004Mid Argyll (north of Crinan Canal): Private
1*** / 0 / 01*** / 1 / 1
2 / 1 / 0
0 / 2 / 1
1 / 0 / 0
1 / 0 / 1
* / 3 / 0
* / 1 / 0
0 / 0 / 1
* / * / 2
* / * / 3
* / * / 1
* / * / 1
Mid Argyll (north of Crinan Canal): Forestry Commission Scotland
1*** / 0 / 01*** / 0 / 0
1 / 0 / *
1 / 0 / *
1 / 0 / *
1 / 0 / 0
1 / 0 / 0
0 / 2 / 0
11 / 10 / 11 /
Mid Argyll (north of Crinan Canal) total
***4 lekking males moving between 2 private and 2 FCS leks 20028
2002 / 2003 / 2004Oban & Lorne: Private
4 / 6 / 64 / * / 2
* / * / 1
* / 1 / 1
* / * / 1
* / * / 1
1 / 1 / 1
* / * / 1
* / * / 1
* / * / 2
* / * / 1
* / * / 1
* / * / 1
* / * / 2
* / * / 1
* / * / 2
* / * / 1
* / * / 1
* / * / 1
* / * / 1
* / * / 3
* / * / 1
* / * / 2
* / * / 1
* / * / 5
* / * / 3
* / * / 1
0 / 1 / 2
Oban & Lorne: Forestry Commission Scotland
2 / 0 / 0* / * / 1
* / * / 1
* / * / 1
11 / 9 / 50 / Oban & Lorne total
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