Butterfly Conservation - saving butterflies, moths and our environment
Butterfly Conservation
saving butterflies, moths and our environment
White-letter Hairstreak Project 2007-2009
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White-letter Hairstreak Recording Project - How will it work?

Many people find searching for White-letter Hairstreaks difficult, but our experience in Hertfordshire and Middlesex is different. The project will take the form of two phases - the finding of elm in spring when in flower and the subsequent seeds which are highly visible - and then to looking for the very active males in the treetops at the very beginning of the flight period.

A computer programme has randomly selected sixteen 10km squares from each 100 x 100km square in England, Wales and the south of Scotland, with a total of 240 areas to be sampled. Within each 10km square, just one 1km square has been randomly selected and this is the initial square to be visited.

Since these squares are completely random, there has been no selection by habitat, so it's quite possible a 1km square might be in the middle of a lake or on the top of a mountain. To see the map and 10km squares selected click here................

First identify the 1km square selected in your area (please tell us so we can mark it off) and then visit to search for elm. Remember that the flowers and seeds are often obvious in spring. If you do find elm, please let us know. Once you have found some elm, you can if you like search for eggs and larvae* (see note below).

If you are positive there is no elm in the target 1km, then revert to look for elm in the standard 2km square that contains that 1km. If again you are positive there is no elm in the 2km square, then look for elm somewhere in the 10km square. This may be more time consuming but hopefully there should be some elm to be found somewhere. The ease or difficulty of finding the elm will be a key component of the project. Please keep us informed whenever you find any suitable elm at 1km, 2km or 10km level.

Please do not trespass - if you are unable to visit the key 1km or 2km square because the land is private please tell us but continue to search the 10km square for elm.

Whether you found the elm at 1km, 2km or 10km level, return at the beginning of the flight period (preferably early morning or late afternoon) and look for the highly visible and very active males. At the beginning of the flight period there is little risk of the butterfly being mis-identified for another species e.g. Purple Hairstreak or Vapourer moth.

For more information on identifying elm and watching males on territory click here........

*Although the presence of multiple eggs would indicate a colony and such records are very welcome, at this early stage in the survey we would also like to find out how closely eggs and larvae counts can be related to adult sightings. Therefore, if eggs are found, we would like to encourage recorders to return, if possible, in the 2007 or 2008 flight season during the period of peak tree-top activity (see Survey tips - adults) to try for adults, so that we can gather some information on this aspect.

If you would like to contact the co-ordinators and discuss the project or telephone 07866654056.

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