Felix wrote:Apparently, samples of mature larvae taken and reared through in recent years from sites around the south of England reveal that Chalkhill Blue larvae are being heavily parasitised. I am not yet aware of what specie of hymenoptera is responsible, but watch this space for more details...
Felix.
Hello Felix,
This would be very interesting. There was no obvious explanation for the dramatic fall in numbers. 2003 was a good year for Chalkhill Blues. The numbers reduction was in subsequent years. However, 2003 may still not have been maximum numbers. Mill Hill recorded about 800 per acre, total in 20 minutes, in 2003. Numbers fell to 200 an acre in 2007.
In Germany, numbers have been more than this in the past. However, I would expect in England that 800 per acre was near the maximum nowadays.
The numbers of Common Blues have also fallen.
History of Mill Hill
http://www.glaucus.org.uk/MillHillHistory.html
Mill Hill 2004
Winter-Spring 2004
http://www.glaucus.org.uk/MillHill2004.html
Summer-Autumn
http://www.glaucus.org.uk/MillHill2004Summer.html
http://www.glaucus.org.uk/Vetch2004.html
Mill Hill 2005
http://www.glaucus.org.uk/MillHill2005.html
Shoreham Bank 2005
http://www.glaucus.org.uk/VetchTrail2005.htm
Mill Hill 2006
http://www.glaucus.org.uk/MillHill2006.html
Shoreham Bank 2006
http://www.glaucus.org.uk/VetchTrail2006.htm
Mill Hill Flikr Search
http://www.flickr.com/search/?q=mill%20 ... 5580%40N00
Mill Hill 2007
http://www.glaucus.org.uk/MillHill2007.html
Shoreham Bank 2007
http://www.glaucus.org.uk/VetchTrail2007.htm
Mill Hill 2008
http://www.glaucus.org.uk/MillHill2008.html
Shoreham Bank 2008
http://www.glaucus.org.uk/VetchTrail2008.htm
Cheers
Andy Horton
glaucus@hotmail.com
Adur Valley Nature Notes (including Shoreham-by-Sea, West Sussex)
http://www.glaucus.org.uk/Adur2008.html
http://www.glaucus.org.uk/Adur2007.html
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