Glow Worms at Sherwood Forest 2012
Click here for details of individual females during 2012
2012 Glow Worms - a detailed summary
Current research work on Glow Worm larvae
 
Final update - August 7th 2012

Following the end of the adult glowing season in early August, we have since published our detailed summary of the 2012 glowing season, but have continued our efforts and are now engaged in accumulating data on Glow Worm larvae during the Autumn months.

Night time surveying at Clipstone Old Quarter, has revealed that there are good numbers of larvae at the top of section J, but counts from other sections surveyed have been very low or none at all. Details on our current research work, can be found by clicking the appropriate link above.

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2012 Spring larvae and adult Glow Worm sightings (Clipstone Old Quarter)
Glow Worms (both adults and larvae) are recorded as follows.....L = larva ..... M = male .....F = female
Note that the male count in the following table, also includes the 'in flight' flash which is characteristic of male Glow Worms.
 
Date   Stage     Additional notes
.........................   L M F      
February 28th   2 0 0     Amazed to find two larvae on our first site visit of the season this evening. Larval lengths were 16mm and 15mm and both were active in section D of the path. Site visited from 17:10h-18:00h. Weather cloudy and mild.
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February 29th   0 0 0     No larvae found this evening. Site visited from 17:30h-18:15h. Weather clear and cool.
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March 3rd   0 0 0     No larvae found this evening. Site visited from 16:50h-17:50h. Weather cloudy and fairly mild.
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March 10th   0 0 0     No larvae found this evening. Site visited from 16:30h-17:30h. Weather clear and mild.
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March 11th   1 0 0     One 17mm larva found in section D this evening. Site visited from 17:00h-18:00h. Weather clear and mild.
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March 22nd   3 0 0     Three larvae found and once again, all were in section D. Larval sizes included singles measuring 16mm, 20mm and 27mm. Weather clear and feeling quite warm.
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March 23rd   1 0 0     One 18mm larva found in section B this evening. Site visited from 17:25h-18:15h. Weather clear and mild.
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March 24th   0 0 0     No larvae found this evening. Site visited from 17:20h-18:15h. Weather clear and mild.
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March 25th   0 0 0     No larvae found this evening. Site visited from 18:10h-19:20h. Weather clear and warm.
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March 26th   0 0 0     No larvae found again this evening. Site visited from 17:50h-18:45h. Weather clear and warm.
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March 27th   0 0 0     No larvae found again this evening. Site visited from 18:45h-19:45h. Weather clear and warm.
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March 28th   1 0 0     One 19mm larvae found this evening in section D, but thought dead as it was curled on it's side. Potted and taken home, but revived and seems OK. Site visited from 18:15h-19:20h. Weather clear and warm.
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March 29th   0 0 0     No larvae found this evening. Site visited from 18:45h-19:45h. Weather clear and warm.
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March 30th   0 0 0     Yet again there were no larvae found this evening. Site visited from 18:15h-19:20h. Weather clear and warm.
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March 31st   1 0 0     One 27mm larva found trampled in section B of the path this evening. Was thought dead and taken home, but remains alive. Site visited from 19:30h-20:00h. Weather clear and cool.
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April 2nd   3 0 0     Three larvae recorded this evening. All coming from section D, with lengths of 21mm (two) and one at 15mm. Site visited from 18:30h-19:30h. Weather cloudy and mild.
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April 4th   0 0 0     No larvae found again this evening. Site visited from 18:45h-19:40h. Weather overcast and cool.
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April 5th   0 0 0     No larvae found this evening. Site visited from 18:30h-19:30h. Weather clear and mild.
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April 6th   0 0 0     No larvae found. Site visited from 18:35h-19:35h. Weather cloudy and mild.
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April 7th   2 0 0     Two larvae recorded from section B this evening. Larval lengths 21mm and 17mm. Site visited from 17:30h-18:25h. Weather cloudy and mild.
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April 8th   4 0 0     A total of four larvae found this evening, but one 17mm larva in section A had been freshly trampled minutes before. Larval lengths of the three live larvae were 23mm, 19mm and 17mm. Site visited from 17:05h-18:05h. Weather cloudy and mild.
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April 10th   1 0 0     A single 19mm larva found in section D this evening. Weather was clear and mild. Site visited from 18:00h-19:00h.
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April 11th   3 0 0     Three larva found this evening, one of which was dead. Larval lengths were 27mm and two at 19mm (one dead) Weather cloudy and mild. Site visited from 17:15h-18:05h.
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April 12th   1 0 0     One 17mm larva found this evening. Weather sunny spells and fairly mild. Site visited from 17:30h-18:30h.
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April 13th   0 0 0     No larvae found. Site visited from 17:00h-18:00h. Weather sunny and feeling mild.
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April 14th   0 0 0     No larvae found. Site visited from 17:45h-18:55h. Weather cloudy and breezy, feeling cool.
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April 15th   0 0 0     No larvae found. Site visited from 17:15h-18:15h. Weather sunny and partly cloudy, feeling cool.
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April 16th   0 0 0     No larvae found. Site visited from 18:45h-19:50h. Weather cloudy and quite breezy.
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April 17th   2 0 0     Two larvae found this evening, despite the unpromising conditions. Larval sizes 22mm and 24mm. Site visited from 17:15h-18:00h. Weather cloudy, breezy and feeling cool.
 
April 20th   2 0 0     After two very wet days with no site visit, two large larvae found this evening, measuring 23mm and 27mm. Site visited from 17:40h-18:20h. Weather cloudy, with occasional light rain.
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April 21st   1 0 0     One larva found in section D this evening, measuring 20mm. Weather sunny, but slightly breezy. Site visited from 17:35h-18:30h.
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April 22nd   2 0 0     Two larvae found this evening measuring 15mm and 24mm. Weather overcast with some rain. Site visited from 17:50h-18:50h.
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April 24th   6 0 0     Perfect conditions and a later survey start paid off with six larvae this evening. A range of larval sizes including 2 x 14mm, 17mm, 19mm, 23mm and 24mm. Site visited from 19:00h-20:00h, weather fine and mild.
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April 26th   1 0 0     One 19mm larva found this evening, just prior to heavy rain. Site visited from 18:50h-19:30h. Weather, cloudy and mild, then heavy rain.
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April 28th   0 0 0     No larvae found. Site visited from 18:10h-19:05h. Weather cloudy and breezy, some rain.
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April 30th   11 0 0     A surprising count of 11 larvae found this evening. Larval lengths included 13mm, 15mm, 16mm, 2 x 18mm, 2 x 19mm, 21mm, 22mm, 25mm and 27mm. Weather fine and mild and site visited from 19:00h-20:10h.
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May 1st   0 0 0     No larvae found. Site visited from 18:30h-19:30h. Weather cloudy and breezy after rain during much of the day.
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May 2nd   8 0 0     Another good count with eight larvae found. All measured 21mm or larger. Site visited from 19:00h-20:15h, weather overcast and breezy.
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May 3rd   2 0 0     Two larvae found late evening, measuring 17mm and 21mm. A survey for adults revealed no females. Site visited from 19:45h-21:30h. Weather overcast and mild.
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May 4th   0 0 0     No larvae or adults found this evening. Site visited from 20:30h-21:50h. Weather cloudy with some light rain and feeling cool.
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May 5th   0 0 0     No larvae or early adults found again this evening. Site visited from 20:00h-21:45h. Weather cloudy and mild.
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May 6th   1 0 0     One 23mm larva found this evening and no adults found in a later search. Weather clear and cool, site visited from 20:10h-21:50h.
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May 7th   5 0 0     Five larvae found this evening, all over 20mm length. A later survey for possible early adults again proved negative. Weather cloudy and mild, with light rain. Site visited from 20:05h-21:50h.
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May 8th   5 0 0     Another five larvae found this evening, with lengths of 18mm, 27mm, 20mm and 2x21mm. Still no adults found. Weather clear and mild. Site visited from 20:35h-21:55h.
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May 9th   0 0 0     No adults found during a thorough search this evening. Weather cloudy with rain, site visited from 21:30h-22:15h.
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May 10th   0 0 0     No larvae or adults found tonight. Weather clear and mild, site visited from 20:45h-22:15h.
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May 11th   1 0 0     A single 24mm larva found this evening and no adults in a later search. Weather clear and feeling cool. Site visited from 20:30h-22:00h.
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May 12th   0 0 0     No larvae or adults found tonight. Weather clear and mild, site visited from 20:45h-22:15h.
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May 13th   0 0 0     No adults found tonight. Weather clear and mild. Site visited from 21:30h-22:10h.
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May 14th   0 0 0     No larvae or adults found tonight. Weather clear and feeling quite cold. Site visited from 21:00h-22:15h.
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May 15th   0 0 0     No adults found tonight. Weather clear and feeling cold, especially at the lowest part of the site. Site visited from 21:30h-22:20h.
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May 16th   0 0 0     Still no adults recorded, but colder this evening than the previous night. Site visited from 21:45h-22:20h.
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May 17th   0 0 0     No adults found tonight. Weather cloudy and mild with occasional very light rain. Site visited from 21:40h-22:15h.
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May 18th   0 0 0     No adults found. Weather cloudy with rain. Site visited from 21:35h-22:15h.
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May 19th   0 0 0     No adults found. Weather cloudy and very mild. Site visited from 21:40h-22:30h.
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May 20th   0 0 0     Despite slightly warmer conditions, no adults have appeared despite the usual thorough site survey. Weather clear and mild, site visited from 22:00h-22:45h.
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May 21st   0 0 0     No adults found. Weather cloudy and mild. Site visited from 21:50h-22:40h.
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May 22nd   0 0 0     No adults found. Weather clear and warm. Site visited from 21:50h-22:50h.
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May 23rd   0 0 0     No adults found. Weather clear and warm. Site visited from 22:00h-23:00h.
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May 24th   0 0 0     No adults found. Weather clear and warm. Site visited from 22:00h-23:00h.
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May 25th   0 0 0     No adults found. Weather clear and warm, with a slight breeze. Site visited from 21:55h-23:05h.
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May 26th   0 0 0     Once again, no adults found. Weather clear and very mild. Site visited from 22:00h-23:00h.
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May 27th   0 0 0     No adults found. Weather clear and warm. Site visited from 22:10h-23:00h.
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May 28th   0 0 0     Still no females found, despite the hot and sunny weather this past week. Silte visited from 22:00h-23:00h. Weather clear and very warm.
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May 29th   0 0 0     No adults found again, but a first encounter with a glowing Geophilid Centipede made up for this. Full account on the 2012 Insect News page. Site visited from 22:10h-23:10h. Weather clear and warm.
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May 30th   0 0 1     The first female of the season finally appeared this evening, located in the grass strip, near the top of section D. Site visited from 22:10h-23:20h. Weather partly coudy and very warm, ground temperatures of 13°C at T1 (lowest point) and 14°C T2 (highest point).
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May 31st   0 0 1     No sign of Female 001 this evening, but a new female was located at the edge of the field in section E. Site visited from 22:10h-23:20h. Weather clear and mild with a bright moon and ground temperatures of 10°C at T1 and 11.5°C at T2.
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June 1st   0 0 4     Female 001 was glowing again this evening and F002 still present. Two new females were found in section D. Weather overcast and warm with a temperature of 12°C at both T1 and T2. Site visited from 22:30h-23:40h.
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June 2nd   0 0 8     Eight females found this evening, with four new females. Weather overcast and mild with a temperature of 12°C at both locations. Site visited from 22:20h-23:40h.
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June 3rd   0 0 0     No females found this evening in very wet conditions. Weather, persistant rain all day and during the survey. Temperatures of 8°C at T1 and 11°C at T2. Site visited from 22:10h-23:00h.
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June 4th   0 0 6     Six females found this evening, with one new female (F009) found within 12" of F002. Weather overcast, slightly breezy and fairly mild. Temperatures of 11°C and 10°C, with the temperature actually slightly warmer at the lowest point (T1). Site visited from 22:10h-23:20h.
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June 5th   0 0 7     Seven females found this evening despite the damp conditions, with two new females in section D. Weather overcast and mild with persistant drizzle, becoming lighter. Temperatures of 11°C at T1 and 12°C at T2. Site visited from 22:10h-23:10h.
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June 6th   0 0 4     Just four females this evening, but one was new. Weather, a heavy shower late afternoon and slightly misty over grassy areas during the survey. Temperatures of 10°C at T1 and 12°C at T2. Site visited from 22:20h-23:20h.
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June 7th   0 0 0     No females found this evening, once again in very wet conditions. Weather, persistant rain all day, becoming lighter during the survey. Temperatures of 10.5°C at T1 and 11°C at T2. Site visited from 22:20h-23:00h.
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June 8th   0 0 6     A total of six females found this evening (one new). Weather, rain on and off for much of the day, becoming dry and windy. Temperatures of 11°C at T1 and 12°C at T2. Site visited from 22:10h-23:15h.
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June 9th   0 0 0     No females found this evening. Weather, feeling mild, clear skies and slightly misty, with temperatures of 10°C at T1 and 11°C at T2. Site visited from 22:25h-23:35h.
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June 10th   0 0 24     A decent emergence of females this evening, with 18 new females out of a total of 24 across the site. Weather, clear and mild with temperatures of 12°C at T1 and 12°C at T2. Site visited from 22:20h-23:45h.
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June 11th   0 0 33     Another good evening, with a total of 33 females found, including 17 new females. Most of the new females appearing, were at the top part of section D. Female 007 reappeared after an absence of a record eight evenings. Weather, overcast with some occasional light drizzle and a temperature of 9°C at both T1 at T2. Site visited from 22:10h-23:45h.
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June 12th   0 0 14     14 females found tonight with just one new female in section M. Weather, overcast but skies clearing and a temperature of 12°C at both T1 at T2. Site visited from 22:20h-23:45h.
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June 13th   0 0 40     A total of 40 females found on the survey, with 13 new females. Weather overcast with occasional (mostly light) rain and temperatures of 12°C at T1 and 11°C at T2. Site visited from 22:20h-00:30h.
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June 14th   0 0 38     An excellent count given the weather conditions, with a good emergence of females in section P, out of a total of 14 new females this evening. The count probably would have been slightly higher, but many females in section D failed to appear. Weather overcast with steady rain becoming heavy. Temperatures of 11°C at T1 and 10°C at T2, site visited from 22:25h-00:10h.
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June 15th   0 0 79     An unexpected large rise in the count this evening, with 79 females including 30 new females. Weather overcast and mild, with a thunderstorm and then showers early afternoon, leading to temperatures of 12°C at T1 and 11°C at T2. Site visited from 22:30h-00:35h.
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June 16th   0 0 70     Another good count this evening and probably the two highest consectutive counts we have had here. 14 new females found this evening and still no males have been recorded with females yet. Weather, partially clear skies, breezy and mild with temperatures of 12°C at T1 and 13°C at T2. Site visited from 22:25h-00:40h.
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June 17th   0 0 71     Quite a number of females failed to appear this evening in what seemed perfect conditions, but there was still another very good count and the third consecutive evening with a total of over 70. Some 19 new females were recorded, but still no males have yet to be found with females. Weather, overcast and warm with temperatures of 12°C at both T1 and T2. Site visited from 22:35h-00:35h.
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June 18th   1 1 16     Just four new females this evening, out of a surprisingly low total of 16. Conditions obviously affected the number of females glowing, with most of those found, being extremely low to the ground. One was even found under moss. One larva was recorded glowing briefly and one male noted. Weather, a fine dry day led to clear skies by dusk and temperatures of 11°C at T1 and 10°C at T2. Site visited from 22:40h-00:15h.
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June 19th   0 3 58     Feeling less damp and cool this evening than yesterday, obviously helped the count as 58 females were found, including 23 new females. Weather, warm and dry during the day, but clouding over late evening, then clearing later. Temperatures of 13°C at both T1 and T2. Site visited from 22:20h-00:35h.
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June 20th   0 2 60     Another 60 females this evening with 29 new females. Weather lightly overcast and dry, with a temperature of 12°C at both T1 and T2. Site visited from 12:45h-00:40h.
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June 21st   0 3 60     60 females recorded again, but with 18 new females. The numbers of new females in some sections may already be in decline, although other sections, such as F, G, K and J, have only just started to, or have yet to produce females. Weather partially overcast, aftera period of heavy rain during the morning. Temperatures of 11°C at T1 and 12°C at T2. Site visited from 22:30h-00:20h.
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June 22nd   0 0 50     Ten new females out of another healthy total of 50 females found this evening. Weather partially overcast and quite windy, but mild with temperature of 13°C at both T1 and T2. Site visited from 22:35h-00:25h.
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June 23rd   0 2 57     Counts remaining unusually high again, with 57 females found this evening. A good emergence of new females, included 23 scattered across much of the site and two found in a new section (S) shown in the two arial site maps below. Weather dry and overcast, with rain from around 23:45h and remaining mild. Site visited from 22:45h-01:00h.
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June 24th   0 2 44     A strange survey this evening and although 43 females were present, none of the numerous females in the grass sections C and D were glowing. This is something we have noted on rare occasions in previous years, despite conditions seeming favourable. However, a cluster of four females were found in another previously unrecorded area during the survey. Weather, clear skies and feeling warm, with temperatures of 13°C at T1 and 14°C at T2. Site visited from 22:35h - 00:15h.
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June 25th   0 1 52     A good emergence of females in many areas other than on grass. Best section was the top of section E, where 13 females were glowing in close proximity, joining the four present the previous night. Once again, there were very few females recorded in the grass sections of A, B, C and D. Weather clear and warm, with temperatures of 13°C at T1 and 14°C at T2. Site visited from 22:20h-00:25h.
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June 26th   0 3 43     43 females found this evening, with 17 new females. Sections E and O are the most active sections currently, but F091 (D) and F031 (A) both reappeared in the grass strip. Weather was partially overcast and very warm, with temperature of 19°C at T1 and T2. Site visited from 22:20h-00:10h.
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June 27th   0 0 30     A total of 29 females found this evening, including 15 new females and the first records from sections G and L. Weather clear and warm, with temperatures of 17°C at T1 and 18°C at T2. Site visited from 22:30h - 00:40h.
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June 28th   1 5 26     26 females found this evening, with a 13mm larva also found motionless and glowing on a dead Bracken stem. Weather clear and warm again, with a temperature of 17°C at both T1 and T2. Site visited from 22:30h-00:20h.
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June 29th   0 3 29     A total of 26 females, which was largely made up of 18 new females. Weather mostly overcast and breezy, but feeling warm with a temperature of 17°C at both T1 and T2. Site visited from 22:30h-00:10h.
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June 30th   0 2 25     A better count than had been expected, with 25 females found this evening. 13 new females made up nearly 50% of the total count. Weather clear with a bright moon and breezy, becoming cloudy. Temperatures of 12°C at T1 and 13°C at T2. Site visited from 22:15h-00:15h
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July 1st   0 1 26     26 females recorded this evening, with 12 new females. F265 reappeared again after being found mating with a male on June 29th, though this is not the first instance of this. Weather, cloudy and mild with temperatures of 12°C at T1 and 13°C at T2. Site visited from 22:15h-23:55h.
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July 2nd   0 1 36     Back up to 36 females this evening, with another good emergence of new females (16) mostly at the top of section E. Weather overcast and warm with temperatures of 16°C at T1 and 17°C at T2. Site visited from 22:15h-00:05h.
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July 3rd   0 2 36     36 females again this evening with 13 new females. Weather overcast and persistant heavy drizzle, but warm with temperatures of 17°C at T1 and 18°C at T2. Site visited from 22:15h-23:50h.
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July 4th   0 1 42     Despite a torrential downpour for around 15 minutes, 42 females were found this evening, with 19 new females. Weather, becoming dry after rain, then slowly clearing and warm, with temperatures of 17°C at T1 and 18°C at T2 again. Site visited from 22:50h-00:45h.
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July 5th   0 3 53     There was the largest emergence of new females of the season this evening, with 34 new females appearing out of a total of 53 found during the survey. Weather was dry after a couple of heavy showers during the afternoon and turning very misty, but warm and with temperatures of 18°C at T1 and 19°C at T2. Site visited from 22:20h-00:35h.
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July 6th   0 0 31     31 females found this evening, despite the very wet day prior to surveying. 14 new females were among the total. Weather dry and misty after persistant rain till mid-evening, with ground temperatures of 12°C at T1 and 14°C at T2. Site visited from 22:15h-00:05h.
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July 7th   0 2 53     Back up to 53 females again this evening, with 14 new females among the total. Weather overcast and feeling warm again, with ground temperatures of 16°C at T1 and 17°C at T2. Site visited from 22:30h-00:30h.
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July 8th   0 1 46     The good numbers of females continues, with nine new females out of a 46 total. Weather overcast and warm, with a heasvy shower late evening after a dry day, leading to ground temperatures of 17°C at T1 and 18°C at T2. Site visited from 22:15h-00:00h.
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July 9th   0 0 58     Another increase in the number of females, with a count of 58 present this evening. Weather was overcast but dry after heavy showers during the afternoon, feeling warm again with temperatures of 16°C at T1 and 17°C at T2. Site visited from 22:10h-00:10h.
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July 10th   0 0 37     Very heavy rain during the afternoon may have led to a drop in numbers this evening, but 37 females were still found. Weather dry and overcast, but with temperatures rising a degree from the initial temperatures taken, to reach 13°C at T1 and 14°C at T2 by the end of the survey. Site visited from 22:10h-00:00h.
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July 11th   0 1 24     24 females found this evening with four new females. Weather clear and feeling cooler after a dry day, with temperatures of 9°C at T1 and 12°C at T2. Site visited from 22:15h-23:50h.
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July 12th   1 2 60     Another unexpected rise in the number of females present this evening, with 22 new females in a high site total of 60. One 13mm larva was found glowing in section G. Weather, dry and overcast and much warmer than the previous evening, with temperatures of 12°C at T1 and 14°C at T2. Site visited from 22:10h-00:15h.
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July 13th   0 0 46     Despite rain over most of the day, there was another good count this evening with a total of 46 females and just three were new. Weather overcast and dry after a wet day, temperatures of 12°C at T1 and 13°C at T2. Site visited from 22:10h-23:55h.
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July 14th   0 2 36     Down to 36 females this evening, with five new females. Weather, clear skies aftera largely dry day, but with showers late afternoon and a temperature of 12°C at both T1 and T2, but ground temperature was lower (9°C) in the grass strip. Site visited from 22:15h-23:50h.
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July 15th   1 3 53     Back up to 53 females this evening, with 11 new females scattered across the site and a 12mm larvae found in section J. Weather, dry and clear with temperatures of 12°C at T1 and 14°C at T2. Site visited from 22:05h-00:00h.
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July 16th   0 1 53     A combination of four new females, females re-appearing after two nights missing and those present again from last night, all helped make up the evening total of 53 females. Weather partially overcast, becoming clear and still warm. Temperatures of 16°C at T1 and 17°C at T2. Site visited from 22:00h-23:45h.
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July 17th   1 1 46     Nine new females were among a total of 46 this evening. Weather partially overcast and warm, with a temperature of 18°C at both T1 and T2. Site visited from 22:00h-00:00h. Another glowing larva (12mm) was found in section J.
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July 18th   0 3 40     Still 40 females this evening, including four new females. Weather dry all day (an afternoon thunderstorm missed the survey area) with a temperature of 16°C at both T1 and T2. Site visited from 22:05h-23:50h.
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July 19th   0 0 31     31 females found this evening, with many of those present over the past few nights seemingly mated. Two new females in sections G and E. Weather, heavy rain early morning, then on and off most of the day and still raining for part of this evening's survey. Temperatures of 13°C at both T1 and T2. Site visited from 21:55h-23:20h.
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July 20th   1 0 28     Looks like the start of the season's decline, with 28 females found, but no new females for the first time since the first week of June. A 10mm larvae was found wandering and glowing about a foot away from Female 566 in section J. Weather, overcast and dry until late into the survey, but rain all morning and into the early afternoon. Temperatures were 12°C at T1 and 13°C at T2. Site visited from 22:10h-11:45h.
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July 21st   0 2 32     A total of 32 females this evening, with three new females present. Weather, dry and lightly overcast, temperatures of 13°C at T1 and 14°C T2. Site visited from 22:20h-23:50h.
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July 22nd   1 1 29     29 females this evening, with three new females. A 15mm larva was glowing as bright as a female in section J. Weather, dry and clear with temperatures of 15°C at T1 and 16°C at T2. Site visited from 21:50h-23:15h.
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July 23rd   0 0 30     Three new females again this evening in a total of 30 found during the survey. Weather, dry and clear, warm again with temperatures of 17°C at T1 and 18°C at T2. Site visited from 22:00h-23:25h.
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July 24th   0 1 27     Down to 26 females present, with just a single new female. Weather, dry and very warm with temperatures of 20°C at T1 and 21°C at T2. Site visited from 21:55h-23:15h.
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July 25th   0 1 23     23 females found this evening, with one new female in section S, that was hardly glowing (one of just a few dim females this season). One meale found 'in cop' with a female this evening. Weather, dry and warm with temperatures of 16°C at T1 and 17°C at T2. Site visited from 22:00h-23:15h.
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July 26th   0 1 18     Down to below 20 females for the first time since June 18th, with just 18 found this evening. Weather, generally clear and very mild, with a temperature of 18°C at T1 and T2. Site visited from 21:45h-23:05h.
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July 27th   0 0 14     No new females and just 14 found this evening. Weather, partially overcast, dry and cooler than of late, with temperature of 13°C at T1 and 14°C at T2. Site visited from 22:00h-23:10h.
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July 28th   0 0 11     No new females in the survey count of just 11 this evening. Weather, dry, clear and relatively mild, with temperatures of 12°C at T1 and 13°C at T2. Site visited from 22:00h-23:00h.
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July 29th   0 0 9     Nine females present. Weather, dry, clear and cooler than the previous evening, with temperature of 10°C at T1 and 11°C at T2. Site visited from 21:50h-23:00h.
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July 30th   0 0 5     Down to just five females this evening, all of which were glowing in locations in the shadow of the bright moonlight. Weather, dry and clear again with temperatures of 9°C at T1 and 10°C at T2, although the air temperature felt several degrees cooler. Site visited from 21:45h-22:45h.
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July 31st   0 0 6     Six females present this evening, with F576 turning up again in section D. Weather, dry, warm and overcast and rain for most of the day. Temperatures of 15°C at T1 and 16°C at T2, site visited from 22:00h-22:50h.
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August 1st   0 0 7     Back up to seven females, with F566 glowing again after missing the last two evenings. Weather clear and quite warm, with temperatures of 15°C at T1 and 16°C at T2. Site visited from 22:00h-22:45h.
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August 2nd   0 0 7     Seven females again this evening, but there was surprisingly a new female in section J. Weather, partially overcast and very mild, with temperatures of 13°C at T1 and 14°C at T2. Site visited from 21:40h-22:45h.
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August 3rd   0 0 6     A count of six females tonight. Weather was cloudy and continuing quite warm with temperatures of 14°C at both T1 and T2. Site visited from 21:45h-22:35h.
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August 4th   2 0 4     Just four females this evening, but two small larvae (12mm and 11mm) were found glowing in close proximity near the top of section J. Weather, partially overcast and becoming clear with temperatures of 13°C at T1 and 14°C at T2. Site visited from 21:45h-23:00h.
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August 5th   0 0 1     Just F566 found glowing this evening. Weather partially overcast, fairly mild and becoming misty. Temperatures of 10°C at T1 and 11°C at T2. Site visited from 21:45h-22:45h.
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August 6th   0 0 0     No females recorded this evening, despite a thorough search of all areas. Weather clear and fairly mild, with temperatures of 11°C at T1 and 12°C at T2. Site visited from 21:35h-22:15h.
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August 7th   0 0 0     No females recorded again this evening. Weather clear and mild, with temperatures of 10°C at T1 and 11°C at T2. Site visited from 21:35h-22:20h.
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August 16th   4 0 0     A short search for larvae this evening, produced three at the top of section J and one in section F. Larval sizes were 12mm, 14mm and two at 15mm. Weather, overcast and very mild, site visited from 23:15h-23:45h.
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August 17th   1 0 0     Another search for larvae this evening, resulted in one 10mm larva glowing on a small stone at the top of section J agian. Weather overcast with some light rain and site visited from 21:45h-22:45h.
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August 19th   11 0 0     11 larvae found this evening. Weather clear and mild. Site visited from 21:40h-23:30h.
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August 20th   15 0 0     15 larvae found this evening. Weather, partially clear skies and warm. Site visited from 21:30h-23:30h. Temperatures were 17°C at T1 and dropping to just 16°C atT2.
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August 21st   13 0 0     A total of 13 larvae were found this evening, which despite surveying several other sections, were all in section J. Weather, clear skies after torrential showers during the mid-late afternoon period, leading to temperatures of 13°C at both T1 and T2.
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August 22nd   17 0 0     Nearly four hours surveying resulted in 17 larvae being found this evening/night. Larval sizes ranged from 9mm (our smallest ever) to 25mm. Sections D, E (lower part) F, G, I, J, K, L, M, N and S, were surveyed at least twice. Weather clear and mild with temperatures of 14°C at T1 and 13°C at T2 at 22:00h, dropping to 9°C at T1 by 01:20h. Site visited from 21:40h-01:30h.
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August 23rd   14 0 0     14 larvae found this evening, with a 28mm female larva found in section F being the largest of the size ranges. The following sections were surveyed, D, E, F, G, I, J, K, L, M and O. Weather overcast and warm with no wind. Site visited from 21:20h-23:45h. Minimum temperatures of 13°C at T1 and 14°C at T2.
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August 24th   11 0 0     A total of 11 larvae were found this evening, Weather, overcast and cloudy, becoming wet with heavy rain. Site visited from 21:20h-23:00h.
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August 25th   7 0 0     Just seven larvae found this evening, with some evidence that they were becoming more active, the longer it stayed dry. Weather, heavy showers most of the day and well into the evening, with a temperature of 13°C at T1 and T2. Site visited from 22:00h-01:45h.
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August 26th   14 0 0     14 larvae found this evening. Weather clear with a bright moon and temperatures of 12°C at T1 and 13°C at T2. Site visited from 21:10h-23:15h.
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August 27th   3 0 0     Just three larvae found this evening. Weather, rain most of the evening which cleared shortly before surveying, but feeling warm with a temperature of 14°C at T2. Site vistied from 21:20h-23:25h.
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August 28th   3 0 0     A further three larvae found again, all were found in areas shaded from the bright moonlight which severely interfered with surveying. Weather, clear and mild with temperatures of 11°C at T1 and 13°C at T2. Site visted from 21:20h-23:05h.
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September 15th   18 0 0     A total of 18 larvae found this evening, with 16 of the total being found after 22:15h, when larvae seemed to become more active. The following sections were surveyed, D, F, G, I, J, K, L and M. Weather clear and mild with temperatures of 10°C at T1 and 11°C at T2 by 00:00h. Site visted from 20:45h-00:30h.
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September 20th   8 0 0     Eight larvae found this evening, with three located in section L. Sections L, M, N, K, J, D, S, F, G, I and E were all surveyed. Temperatures of 11°C at T1 and 12°C at T2 were recorded at 23:00h, weather overast and mild. Site visited from 21:00h-00:10h.
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September 22nd   1 0 0     Just a single larva (unmeasured) found glowing in section J this evening, probably due to the cooler temperature. Sections L, M, F, G, I, J and K were surveyed. Weather clear and cool, with temperatures of 7°C at T1 and 8°C at T2 at 21:00h. Site visited from 20:15h-21:45h.
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October 3rd   0 0 0     No larvae found this evening in an hour's surveying, but temperature only at 7°C at T1 and 8°C at T2. Sections L, K and J surveyed, with site visited from 19:30h-20:30h.
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October 10th   3 0 0     An hour's survey produced three hunting larvae near the top of section J this evening. Weather lightly overcast, with tempertures of 8°C at T1 and 9°C at T2. Sections F, K, J and L were surveyed.
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October 13th   0 0 0     No larvae found this evening, but a clear sky and tempertures of 6°C at both T1 and T2. Sections L, M, J and K were surveyed. Site visited from 20:00-21:05h.
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October 15th   0 0 0     No larvae found. Weather clear and feeling mild, with tempertures of 8°C at both T1 and T2. Site visted from 19:30h-20:45h.
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October 17th   4 0 0     Four larvae found this evening and all between 21:25h-21:55h. Weather lightly overcast, becoming cloudy with light rain and tempertures of 8°C at T1 and 9°C at T2, later dropping to 8°C at T2. Sections D, F, I, J, K and L were surveyed.
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October 18th   2 0 0     Two larvae found. Weather, lightly overcast and mild with a temperature of 11°C recorded at T1 and T2. Sections F, J, K, L, M and O were surveyed several times each. Site visited from 21:30h-23:30h.
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October 19th   4 0 0     Four larvae found in just under three hours surveying this evening. Weather overcast with some light rain, mild with initial tempertures of 12°C at T2, later falling to 9°C. Sections D, F, G, I, J, K and L were surveyed several times each. Site visited from 21:00h-23:50h.
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October 20th   1 0 0     Just a single larvae found this evening. Weather overcast with a temperature of 8°C at both sites. Sections D, F, G, I, J, K, L, M and N surveyed. Site visited from 21:30h-23L30h.
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October 22nd   6 0 0     A surprising total of six larvae recorded this evening. Weather foggy (making the whole site extremely dark) and very mild, with a temperture of 12°C, dropping to 11°C at T2. Sections F, G, I, K, L and J were surveyed several times, but all larvae were found in the upper part of section J.
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October 23rd   11 0 0     The mild conditions seem to have prompted more larvae to become active, with a total of 11 found this evening. Weather overcast, with the cloud lowering after 22:00h. Temperature 12°C at both T1 and T2. Sections D, F, G, I, J, K, L and M were surveyed. Site visited from 19:30h-22:30h.
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October 24th   2 0 0     Another mild and damp evening, but just two larvae found, although one of these measuring just 7mm in length was obviously off a 2012 female. Weather, overcast with almost constant drizzle with the temperature at T2 dropping from 12°C to 10°C. Sections D, F, G, I, K, J, L and M were surveyed. Site visited from 19:30-22:00h.
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October 25th   0 0 0     No larvae found this evening. Weather, lightly overcast, becoming clear with bright moonlight. Temperature of 7°C at T2. Only the darker sections of F, G and J were surveyed because of moonlight interference. Site visited from 19:30h-20:40h.
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November 6th   0 0 0     No larvae found despite quite favourable temperatures of 8°C at T2. Sections D, F, G, I and J were surveyed. Site visited from 19:30-21:00h.
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November 7th   0 0 0     No larvae found. Weather lightly overcast with skies clearing. Temperature at T2 dropping quickly from 8°C-6°C. Sections D, J and F were surveyed. Site visited from 19:15h-20:45h.
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November 8th   0 0 0     No larvae found. Weather lightly overcast with the temperature at T2 dropping from 10°C to 7°C. Sections D and J were surveyed. Site visited from 20:10h-21:10h.
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November 9th   0 0 0     No larvae found this evening. Weather overcast with light rain and a temperature at T2 of 8°C. Sections O, L, J and K were surveyed. Site visited from 20:15h-21:20h.
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November 12th   2 0 0     Two very late larvae found this evening in section J. Weather, clearing skies with temperature at T2 of 8°C, dropping to 6°C. Only section J was surveyed, site visited from 19:30h-20:30h.
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November 13th   0 0 0     No larvae found this evening. Weather overcast and mild, with a temperature of 9°C at both T1 and T2. Sections F, G, I, J, L and M were surveyed. Site visited from 18:05h-19:15h.
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December 16th   0 0 0     No larvae found this evening. Weather, clearing skies and a temperature of 4°C at T2. Site visited from 21:05h-22:00h.
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December 22nd   0 0 0     No larvae found this evening. Weather overcast and very mild with a temperature of 11°C at T2. Site visited from 18:50h-19:50h.
 
 
Below:- Arial map showing the positions of all female Glow Worms at Clipstone Old Quarter during 2012.
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Below:- Arial map showing the survey route we take each night. Sections A, B, C and D are the only areas where larval counts are made. This map has recently been updated (June 24th 2012) to include the extension to section E and the new section S, following the discovery of Glow Worms along these paths/tracks for the first time. The two yellow dots show the two locations (highest and lowest points on site) where the temperature is taken during the season.
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Larval sizes found during Spring 2012
    Glow Worm larval size/average per year  
Week/period . 2009 2010 2011 2012 Wkly avg
March 22-31 . ..... ..... 18.03mm/27 21.16mm/6 19.59mm
April 1-7 . 23.33mm/3 21.27mm/13 18.64mm/70 19.00mm/5 20.56mm
April 8-14 . 21.14mm/14 19.58mm/17 19.19mm/31 19.66mm/9 19.89mm
April 15-21 . 20.45mm/10 20.78mm/18 19.78mm/53 23.20mm/5 21.05mm
April 22-29 . 23.32mm/25 18.74mm/53 19.97mm/39 18.77mm/9 20.20mm
April 30-May 6 . 22.95mm/20 23.20mm/5 21.87mm/8 20.95mm/22 22.24mm
May 7-14 . 22.08mm/17 23.25mm/4 ..... 22.30mm/10 20.72mm
May 15-22 . ..... 19.66mm/6 ..... ..... .....
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Spring average . 22.21mm/89 20.92mm/116 19.58mm/228 20.45mm/66 .....
  Always looking to contribute something different to the study of Clipstone Old Quarter's Glow Worm population, we have recently been looking at the average size of all the larvae found since 2009. This proved to be quite interesting and has revealed some striking differences from year to year, something that we had not realised before.

In 2009 and 2010, the average larval sizes were considerably greater than those recorded in 2011. In 2009, the average length was found to be 1.30mm larger than in 2010, but a huge 2.63mm larger than in 2011. So far, 2012 has seen an average increase in larval lengths of around 0.50mm, over the figures recorded for 2011.

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The table above shows the averages attained during each weekly period of larval surveying since 2009. This year's data will be added daily as the Spring progresses. The table should be self explanatory, with the average larval lengths shown in millimetres per week. The figure after the forward slash represents the total number of larvae from which the weekly average is calculated.
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We have looked at the period of April 1st -7th of each survey year, taken the average larval size found and then compared them with the recorded rainfall between the months of May to August & September to March.  
Summer period Rainfall . Winter period Rainfall Survey period Spring Size (Avg)
May 08 - Aug 08 313.80mm . Sep 08 - Mar 09 452.00mm April 1-7 2009 23.33mm
May 09 - Aug 09 306.10mm . Sep 09 - Mar 10 462.70mm April 1-7 2010 21.27mm
May 10 - Aug 10 223.90mm . Sep 10 - Mar 11 372.00mm April 1-7 2011 18.64mm
May 11 - Aug 11 215.20mm . Sep 11 - Mar 12 340.50mm April 1-7 2012 19.00mm
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The rainfall is based on Met Office rainfall data for the Midlands area. There seems to be a possible correlation between Spring larval sizes and the amount of rainfall during the preceding 11 months. In the table, we have divided the 11 months into two periods, just to see if the data held up for the preceding Summer, as it seems to do with the preceding Winter. But two other factors to consider are food availabilty (which would be as affected by rainfall as larval growth) and the mean temperature throughout both periods. Adult female Glow Worms very rarely glow when the temperature is below 8°C, so it would be safe to assume that larvae will also be inactive at similar temperatures.
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Month   Size range Size (Avg)
June . 10-17mm/4 14.25mm
July . 13-22mm/16 15.00mm
August . 13-27mm/13 17.23mm
  So what of larval sizes during the rest of the year? It is generally agreed that most larvae take two years to reach maturity, but there are obviously exceptions to this rule depending on how much food a larva finds within it's first three or four months after hatching, otherwise adults would be expected to occur every other year. Larvae found in June- August will have hatched from eggs laid about a year previous and will continue to grow until passing a second Winter nearly full grown and completing their growth the following Spring.
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We currently have data on a total of 33 larvae found during the period June to August in the past three years. The average larval lengths are broken down and shown in the above table. As before, the figure after the forward slash represents the total number of larvae from which the average is calculated.
     
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