Glow-worms Lampyris noctiluca L. (Coleoptera: Lampyridae) in Essex:
results of the 2001 Essex Glow-worm survey
TIM GARDINER, MICHELLE PYE & ROBIN FIELD
Centre for Environment and Rural Affairs (CERA), Writtle College, Lordship Road, Writtle,
Chelmsford, CU1 3RR
Abstract
A countywide survey of the Glow-worm Lampyris noctiluca L. (Coleoptera: Lampyridae) was
undertaken in 2001, which aimed to ascertain the current distribution of this species. The survey
involved establishing a transect at a potential or known site and walking it three nights during the
summer. In addition, casual observations of L noctiluca were accepted so that the Essex distribution
could be determined. The survey indicates a widespread but localised distribution for L noctiluca,
although this species is not as rare as previously thought, with observations having occurred at 43
sites since 1992.
Numbers of L. noctiluca observed on the transect walks were mostly low. The highest count of the
survey occurred at One Tree Hill, where 76 individuals were observed. One Tree Hill is part of
Langdon Hills Country Park, near Basildon, and is of great importance for L. noctiluca in Essex, as
37% of individuals recorded during the transect walks were observed at this site. The preferred
habitats were meadow and scrub, predominantly in dark, unlit areas. Few L. noctiluca individuals
were recorded near any form of artificial lighting. The status of this species in Essex appears to be
relatively secure in the short-term, although development pressure, pollution and neglect of sites
are the main long-term threats.
Introduction
For many centuries the Glow-worm Lampyris noctiluca L. (Coleoptera: Lampyridae) has inspired
naturalists and poets due to the pale green glow which is emitted by the adult female on warm
summer evenings. Leutscher (1974) fondly recalls his camping days in Epping Forest when
specimens were collected and hung in jam-jars inside tents, with the light emitted apparently strong
enough to read by. The female's glow is produced via a complex series of chemical reactions and
is used to attract the flying adult male. L. noctiluca is primarily an insect of unimproved grassland
and other habitats such as old woodland (Tyler 1994).
In Essex, L. noctiluca has been described as rare (Corke 1984), with the county recorder having
records for only 13 sites (Hammond pers.comm.). Many of these records are extremely old and
give very imprecise information on the exact location of the observed colony, for example, TM02
Colchester 1903. The apparent rarity combined with the possible under-recording of this species
in Essex led the authors to organise a countywide survey of L. noctiluca in 2001. The main aims of
the survey were to ascertain the current distribution and main strongholds for L. noctiluca in Essex.
Method
Survey participants were required to count glowing females along a chosen transect route on three
occasions during July and August 2001. In addition, any casual records of L. noctiluca since 1992
were accepted so that the distribution of this species could be more accurately ascertained. The
survey was widely publicised in various newspapers throughout the county and on BBC Radio
Essex. Leaflets were distributed to nature reserve visitor centres and a press release was posted on
Essex Naturalist (New Series) 19 (2002)
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