Thought you might like to see what I came up with in the end, Littlestone, as you were the one listening to my online rants about lack of inspiration on Firday night. I didn't use the barn owl in the end. I went for a heron and some swallows:

http://www.janetomlinson.com/images/paintings/buttercupsnearoxford.jpg

No megaliths, though, so I guess this is WAAAY off topic. (grovelling apologies to purists)
J
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