NBIS Glow-worm Survey

From Springwatch to Glow-worm Watch

With the BBC's Springwatch programme bringing Norfolk wildlife into every living room, a call has gone out to the county's wildlife watchers to help spot a creature that has so far eluded the cameras - the glow-worm.

Norfolk Biodiversity Information Service (NBIS) has launched a survey to find any hot-spots for these fascinating creatures in the county.

HAVE YOU SPOTTED A GLOW-WORM?

(e.g. more than 20 records, including records at more than one location
 and on several different dates

Photo: Glow-worm (Reproduced under Creative Commons Licence - commons.wikimedia.org/wiki/File:Lampyris_noctiluca_glow_worm.jpg)

Glow-worms aren’t worms at all, but belong to a family of beetles called the Lampyridae. You can see them after dark during June and July. Just the adult female glows using a chemical called luciferin – the same chemical used by fireflies - to produce a pale green light to attract a male, she has no wings and a segmented body.

Biodiversity Information Officer, Martin Horlock said: “We don’t have many records of glow-worms in Norfolk – although we think they’re out there. Only the adult females are easy to spot, and then only for a few hours over the course of a couple of weeks at night. If we have a better idea of where they are distributed, we will be able to investigate whether populations are stable and what we can do to help them thrive.”

                                               Glow-worm distribution in Norfolk prior to first public survey (April 2010)

The male adult glow-worm is much smaller than the female and looks like a typical beetle with full wings. Females can be up to 2.5 cm long, whilst males are often half that size. Your best chances of seeing glow-worms are: from mid June to mid July on a moonless or overcast night; on heathland, grass verges, along disused railway lines, churchyards, woodland clearings or rides.

Photo: Glow-worm, Female (Roger Key)                                           Photo: Glow-worm, Male (Roger Key)

If you have spotted them you can record your sightings on line at this website or you can send us your records by email nbis@norfolk.gov.uk, or by post - using our Glow-worm survey form. Records should contain information about : what you saw, where you saw it (grid reference, habitat and place name); how many glow-worms you saw; and who you are.

The survey has been launched as part of UK efforts to raise local awareness of biodiversity during the International Year of Biodiversity (IYB- UK). IYB is a United Nations campaign which seeks to highlight the role biodiversity plays in our lives, and to highlight efforts underway world-wide to safeguard this irreplaceable natural wealth.

More about glow-worms:

As dusk falls in early summer, the wingless females waiting in the grass and low vegetation, display their lights, turning their bodies so their lamps are visible to the males flying above. Male glow-worms have much larger eyes than the females and they fly towards the light, so a glowing female soon attracts a mate. After mating, the female puts out her light and gets on with egg laying. The larvae which hatch from the tiny eggs are just 5mm long at first. They are predatory and feed on small slugs and snails which they seize with their jaws and inject with a toxin. This immobilises and liquefies the prey which can then be eaten. The larvae, which resemble the wingless adult female, live under stones and logs in damp places. The glow-worm life cycle takes one to three years, with adults emerging in June to July. Adult glow-worms don’t feed and live only for a couple of weeks. Although it is the female glow-worm that emits the strongest light, all stages of this insect are faintly luminescent, including the male beetles, larvae and eggs. This may be a warning signal to predators like toads not to eat them, as they’re mildly toxic. Glow worms are fairly widespread in Britain, but localised in distribution. They are usually found on grassy slopes, verges and hedge banks, on heaths and open grassland, especially in chalky areas. They are mostly nocturnal and dislike areas that have been cultivated, or grasslands that have been ‘improved’ (through addition of herbicides or fertiliser). Find out more about glow-worms at www.glowworms.org.uk.

Please tell us if you find any Glow-worms. Records should contain information about: What you saw; When you saw it; Where you saw it (grid reference); and Who you are.

You can record on-line by clicking on the link below. Or you can send us an email at nbis@norfolk.gov.uk or get in touch by phone 01603 224458 or post at NBIS, Room 301, County Hall, Norwich, NR1 2SG.