Butterfly Conservation - saving butterflies, moths and our environment
Butterfly Conservation
Hertfordshire & Middlesex Branch
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Transect Monitoring

Transect recording in Hertfordshire & Middlesex

Link sections on this page . . .
Recording introduction page
General recording
Big Butterfly Count
Wider Countryside Butterfly Survey
Branch Annual Reports
Transect Page index

Just under 60 transects are currently being walked in Hertfordshire and Middlesex.

The transects walked in Hertfordshire and Middlesex since 2005 are listed here - click on link for more details

This is the most formal method of recording and should only be carried out by experienced observers who can recognise virtually all butterfly species on the wing and who can commit to walking a set route for all or most weeks from the start of April to the end of September.

A route should take about 30 minutes to walk when there are no butterflies, as this will expand to more than an hour at the height of summer. A good length is between 1-3 kilometres (up to about 2 miles). The route is divided into sections that correspond to particular habitats and there can be up to 15 sections.

This method gives information on the variation in butterfly numbers within the season, and from year to year and can also be invaluable in helping to guide and review management for butterflies on a particular site..

The route must be walked in set weather conditions: There are some weeks, particularly early in the season, when these meteorological conditions cannot be met. Again it is better to walk the transect when it is a bit too cold or too cloudy rather than not to walk it at all, but a careful note of conditions should always be kept.

Records are ideally submitted each week onto the Transect Walker online at the UKBMS website. Registration is needed to use this site and to register a transect if it is a new one.

If you do not have any computer access records can be submitted on paper sheets and sent to Andrew Wood at the end of the season.
Click here to print an online copy of the weekly transect form
Click here to print an online copy of the summary form

Using the online system is preferred as it saves errors generating by transcribing handwritten records.

Andrew Wood (details on Committee page) the local UKNBM coordinator has access to all the records entered and checks the data input and will query any unusual records.
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