Butterflies in the Stevenage area

Welcome!

Stevenage transect annual totals
Knebworth Park transect annual totals
Knebworth Woods transect annual totals

This website provides information on butterflies reported in the Stevenage area since 1993. The reports are based on records submitted by observers for the area encapsulated in the Ordnance Survey grid reference TL22 10km decad which includes villages Walkern and Great Wymondley, for example. I am most indebted to Andrew Wood, the county butterfly recorder, for supplying the records and a big thank you to all the recorders without which this project would have been possible. Records for 1993 and 1994 relate to my transect only covering the southern section of Fairlands Valley Park.

Distribution maps are taken from the MapMate database onto which the TL22 data had been applied. The distribution for all species is represented at 2km level (tetrad) as is standard for county distribution maps. Presence of a particular species in a tetrad is dependent on when it was seen since 1995. For the 1995-2009 period presence is denoted by an un-filled diamond; presence during 2010-2019 is represented by a blue square. The darker the blue square the more records submitted and probably increased abundance. Green circles imply that the species was seen since 2019.

Abundance charts refer to timed or monitored visits only like transects and walks undertaken for the Wider Countryside Butterfly Survey otherwise to discern trends would be meaningless. The Big Butterfly Count records are not being counted because the scheme was initiated only in 2010 but references to it are noted for any significant sightings.

I had considered using all data for phenology (flight period) charts but there appears to be a proportionately large number of records for late July and August (the school summer holidays) and of course the Big Butterfly Count scheme takes place during this period. Transect data only is used for preparing phenology charts except for the rarer species where phenology might be better represented for a wider area, for example, the TL22 decad as a whole.

Only species which were reported since 1995 and those seen on the Stevenage transect since 1993 are described. The one exception is the Brown Hairstreak, with unconfirmed reports from Norton Green. Those species, excluding migrants, not believed to hold colonies in the Stevenage area are highlighted in red on the left.

To find out more on species in general refer to the 'Species Accounts' webpage or click on the species you are interested in, on the left.

I must thank Ian Carle, Jenny Oxley, Bob Press and Jo Ward for allowing me to have access to records and collections at the Herts Environmental Records Centre (HERC) at Grebe House, St Albans, Mill Green Museum at Hatfield, Hitchin Museum and Stevenage Museum respectively. I am grateful to Bob Clift for his help and checking my web pages on his Mac.

Photographs on this website were taken by me unless otherwise stated.

If you wish to make comments regarding content on the website or anything else please email me.