www.ukbutterflies.co.uk

Upper Thames BC Branch Black Hairstreak 2005 report is available at

http://www.upperthamesbutterflies.co.uk ... 2005SH.pdf

Cheers,

- Pete

Upper Thames BC Branch Black Hairstreak page:

http://www.upperthamesbutterflies.co.uk ... akPage.htm

Cheers,

- Pete

It seems the Black Hairstreak had a population explosion in 2004. How did it fare in 2005?
Were there particularly favourable conditions in 2004?

So far I have records of over 100 visits in 2005 to the various Bl H sites in our region during the butterflies flight period, with just a few more yet to come, this includes visits when no Bl H were seen, from this we can calculate that just under 2.75 were seen per hour, this is way down on the 6.87 seen in 2004, with the highest hourly rate in any of the previous 6 years only 2.2 and lowest .6
The most likely reason for the explosion in 04 was probably the lack of late spring frost's, which we understand has an impact on the number of adults seen.
In 05 we had frost's 9--13 and again on the 15 of May, records indicate that the last explosion in numbers was in 1986 and possibly 1987, as yet I have been unable to discover if there was an absense of late frost's in those years.
What is a mystery is how the little catterpillars can survive the bad weather of the Blackthorn winters which we seem to get every year only to perish when fully grown.
Hope this answers your Question. U.T.T.B. Bl H Champion

Black Hairstreak eggs have a reputation for being hard to locate. We have a search party lined up for Saturday so let's hope the weather is kind!

best wishes

Tom Dunbar