Glow-worms Lampyris noctiluca L (Coleoptera: Lampyridae) in Essex
Declines
L. noctiluca has declined in areas such as Epping Forest which used to possess scattered colonies
in the early 1900s (Leutscher 1974). Although the forest was particularly targeted during the 2001
survey, individuals were not observed at any of the five sites which were visited. Only one colony
has been recorded within the forest in recent times (at Goldings Hill on 10th June 1992, TQ431982).
therefore L. noctiluca is probably very rare in this area. Searches in 2001 at other sites with old
records for L. noctiluca were mostly unsuccessful. This species would appear to be extinct at
Maldon Wick, Hazeleigh Wood, Chatham Green and the seawall at North Fambridge. Some colonies
are also extremely threatened, predominantly by development pressures. For example, although
several colonies were recorded in the grounds of the Braintree Freeport complex in 2001, an adjacent
housing development has severely reduced grassland habitat availability and consequently the
number of individuals in one of these colonies has rapidly declined since the late 1990s.
Transect recording
L. noctiluca was observed at 16 of the sites where transect walks were conducted. A total of 507
glowing females were recorded during the transect walks. The majority of these individuals were
observed in period one (9th - 22nd July), during which the highest count of the survey also occurred.
In the subsequent walk periods, observations gradually declined and only 104 individuals were
recorded in period three (6th - 19th August). The highest count during the final period occurred at
Hadleigh Castle, which was the only site where more individuals were observed in the final walk
period than in the previous two.
Overall, counts of L. noctiluca individuals were generally very low (Fig. 3). Observations comprising
only one glowing female occurred nine times during the survey. Although four counts comprising
over 30 individuals did occur during the survey, three of these were recorded at One Tree Hill. The
highest count of the survey was 76 glowing females, which were observed at One Tree H ill on July
11th.
Fig. 3. Frequency of counts
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Essex Naturalist (New Series) 19 (2002)