Welcome to the Dragonflies of Worcestershire
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This site is intended as a follow up to the book "The Dragonflies of Worcestershire", by Mike Averill, keeping recorders informed about the latest distribution of dragonflies in the county. Records are always welcome of any sightings and you can forward those records in a number of ways (See ways of recording information), one simple way is to email this site using the Send sightings / Contact tab on the top bar. Unusual sightings or queries can also be sent in the same way and Mike will happily answer them
The site also contains information about where to see dragonflies and what is going on in the county and is geared towards monitoring the flying season
If you want identification help try the British Dragonfly Society ID Page Here
What's on this front page?
Headline News
The status of the Club-tailed Dragonfly in Worcestershire
On the Wing 2023 - what to look for
On the Wing A look back at the 2022 Sightings and emergences
Dragonfly Buzz- science news about Dragonflies
All the first sighting dates for each species are in the table at the bottom of this page
All the annual accounts are found under the more tab
This site is intended as a follow up to the book "The Dragonflies of Worcestershire", by Mike Averill, keeping recorders informed about the latest distribution of dragonflies in the county. Records are always welcome of any sightings and you can forward those records in a number of ways (See ways of recording information), one simple way is to email this site using the Send sightings / Contact tab on the top bar. Unusual sightings or queries can also be sent in the same way and Mike will happily answer them
The site also contains information about where to see dragonflies and what is going on in the county and is geared towards monitoring the flying season
If you want identification help try the British Dragonfly Society ID Page Here
What's on this front page?
Headline News
The status of the Club-tailed Dragonfly in Worcestershire
On the Wing 2023 - what to look for
On the Wing A look back at the 2022 Sightings and emergences
Dragonfly Buzz- science news about Dragonflies
All the first sighting dates for each species are in the table at the bottom of this page
All the annual accounts are found under the more tab
Thinking of going to Cyprus this year? You could combine that with the 2023 International Congress of Odonatology which is being held in Cyprus in June.
The symposium will be held in the resort town of Paphos, on Cyprus. The congress venue will be Neapolis University, which has modern facilities and onsite accommodation. There will be field trips to see the small but interesting list of species found locally. June is the optimum month for odonatologists to visit Cyprus, when dragonflies are most abundant and the charismatic species Epallage fatime (Odalisque), Anax immaculifrons (Magnificent Emperor), Europe’s largest dragonfly, and Caliaeschna microstigma (Eastern spectre) and the island’s speciality, Ischnura intermediate (Persian Bluetail) are at their peak
https://worlddragonfly.org/meetings/ico2021-preview/
The symposium will be held in the resort town of Paphos, on Cyprus. The congress venue will be Neapolis University, which has modern facilities and onsite accommodation. There will be field trips to see the small but interesting list of species found locally. June is the optimum month for odonatologists to visit Cyprus, when dragonflies are most abundant and the charismatic species Epallage fatime (Odalisque), Anax immaculifrons (Magnificent Emperor), Europe’s largest dragonfly, and Caliaeschna microstigma (Eastern spectre) and the island’s speciality, Ischnura intermediate (Persian Bluetail) are at their peak
https://worlddragonfly.org/meetings/ico2021-preview/
Ever wondered what happens to all the dragonfly records that you send in?
Locally that data is used by the Biological Records Centre at Worcester to answer queries about the impact of any land use changes. Nationally the whole of the country's data is used to assess how dragonflies are doing on a regular basis. See the item in Dragonfly Buzz (Bottom of this page) about how the Small red-eyed Damselfly has affected other native species as it colonised the UK
The British Dragonfly Society has produced The State of Dragonflies 2021 and you can see the full document here
Headline information from this report says that Trend analyses carried out by the UK Centre for Ecology & Hydrology for this BDS show that 19 of our resident and/ or regular migrant species (41%) have significantly increased in occupancy since 1970. These included common and/or widespread species and scarce and/or localised species, as well as five new colonists. Just five (11%) of our resident and regular migrant species have shown significant declines overall. One of these is a widespread damselfly, two are predominantly upland and/or northern species, and two are specialists of seepages, pools and small streams. In addition, one scarcer migrant has shown some signs of a decline, though appearances have always been somewhat erratic. Most of these changes are likely to be down to Climate change. For Worcestershire, it means that we now have 33 species recorded, with 9 new species since 1995. But there are fears that the commoner species may be declining so it is important to record all the dragonflies that you see on a field visit including the common ones.
Locally that data is used by the Biological Records Centre at Worcester to answer queries about the impact of any land use changes. Nationally the whole of the country's data is used to assess how dragonflies are doing on a regular basis. See the item in Dragonfly Buzz (Bottom of this page) about how the Small red-eyed Damselfly has affected other native species as it colonised the UK
The British Dragonfly Society has produced The State of Dragonflies 2021 and you can see the full document here
Headline information from this report says that Trend analyses carried out by the UK Centre for Ecology & Hydrology for this BDS show that 19 of our resident and/ or regular migrant species (41%) have significantly increased in occupancy since 1970. These included common and/or widespread species and scarce and/or localised species, as well as five new colonists. Just five (11%) of our resident and regular migrant species have shown significant declines overall. One of these is a widespread damselfly, two are predominantly upland and/or northern species, and two are specialists of seepages, pools and small streams. In addition, one scarcer migrant has shown some signs of a decline, though appearances have always been somewhat erratic. Most of these changes are likely to be down to Climate change. For Worcestershire, it means that we now have 33 species recorded, with 9 new species since 1995. But there are fears that the commoner species may be declining so it is important to record all the dragonflies that you see on a field visit including the common ones.
How is the Club-tailed Dragonfly doing at Bewdley, Worcestershire.
Click here to see how many Club-tails (Gomphus vulgatissimus) have emerged in the long running transect count. . Please report any sightings especially if you see any near the River Avon
Click here to see how many Club-tails (Gomphus vulgatissimus) have emerged in the long running transect count. . Please report any sightings especially if you see any near the River Avon
Recording the commoner Wildlife
People don't record the commoner animals, we have very few records of house mice for instance, and so the Wildlife Trust is running a spot the common species in your area, and this year we are still looking for Broad-bodied chasers and Large Red Damselflies as well as some new subjects like Mistletoe and Goosander.
https://www.worcswildlifetrust.co.uk/wildlife-sightings
People don't record the commoner animals, we have very few records of house mice for instance, and so the Wildlife Trust is running a spot the common species in your area, and this year we are still looking for Broad-bodied chasers and Large Red Damselflies as well as some new subjects like Mistletoe and Goosander.
https://www.worcswildlifetrust.co.uk/wildlife-sightings
Worcestershire’s 31st Dragonfly/Damselfly found - this time not a migrant dragonfly but the near threatened --------- Scarce Blue-tailed Damselfly
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A new species for Worcs, this time a damselfly appeared at Feckenham in August 2020. This is a species that was predicted as likely to get to Worcestershire but it was expected to be found in one of the gravel pits first. As its name suggests it is like the Blue-tailed which is ubiquitous in the county but this new species is associated with heathland or semi natural habitats like recent gravel workings. They often go for what seems like very temporary habitat lsuch as water filled wheel ruts.
Look for the way the blue tail is slightly moved down the abdomen compared to the standard blue-tail. Immature females are a striking orange colour which stands out from other blue-tails with which they can be found. The flight season doesn't normally go very far beyond the end of August A second site was found at Ryall in 2021 and is proving to be a strong colony in 2022 Photo – Andy Warr |
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Worcestershire’s 32nd dragonfly added to the list.
Quite unexpectedly the Keeled Skimmer has been seen for the first time. Once again Andy Warr proves to be the man on the spot when he managed to photograph three males at a gravel pit near Upton. Worcestershire has always been in a bit of a blank spot for this species despite it being widespread in Europe. It likes streams, ditches and runnels as well as acid bogs, flushes and seepages. The exact location cannot be disclosed because it is a working gravel pit with restricted access. Anyone going there would obviously do so at their own risk see On The Wing 07 Aug 2022 photo Andy Warr |
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Things to look forward to in 2023
The 33rd species recorded in the County, the Willow Emerald will no doubt expand rapidly this year after suddenly appearing in 2022. This species is the second most successful damselfly to colonise England in recent times following after the Small Red-eyed Damselfly. As the name implies the Willow Emerald is associated particularly with willow growing close to water. You can even look for this species in the winter as the female leaves characteristic scars on willow branches as it lays its eggs in to the bark. Young branches which hang over water are favoured and the Dragonfly society will accept records of these scars.
The species may be confused with other emerald damselfly species, but can be distinguished by:
- Large, pale pterostigma (wing spots).
- Prominent green spur on the side of the thorax.
- No blue colouration in males.
- Pale white appendages of the male
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One way to look for the presence of the Willow Emerald is to search willow branches that are over -hanging water for scars where the females have laid eggs.
On The Wing 2023
What will be the first record? a Large red damselfly, a vagrant Emperor
A look back to what was on the wing in 2022
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08 Oct 2022 We had a shot a few weeks ago of a Flying Southern Hawker so it is useful to borrow this one from Roger Mason which features a Migrant Hawker. They do a lot of hovering so you should be able to see the darker thorax with short yellow shoulder marks compared to the much larger headlamp bars on the top of the thorax in the Southern Hawker. These two species will still be around as long as the weather is occasionally warm and bright.
24 Sep 2022 A bit like buses, after the first Willow Emerald, suddenly we have got 5 locations. Spetchley park is proving to be the site with most individuals and yesterday the latest addition is Feckenham, where one male was seen by Keith Reilly
09 Sep 2022 The Willow Emerald may well be hiding in plain site as we now find that it had been unknowingly photographed on the 24th August at Grafton Wood and today it has been seen at Spetchley and a further site in Birmingham. They may be already more widespread than we think (Ph. below Roger Mason)
21 Aug 2022 With talk of common species possibly being less common, it was good to see something at Kemerton Lake that restored some faith. The post in the shot below was covered with what was probably thousands of shed cases of Common Blue Damselflies. This is only the part of the top of the post which was completely shrouded in exuviae. Under some of those, an Emperor case can just be seen.
07 Aug 2022 Totally unannounced the 32nd Dragonfly to Worcs, is found at a Gravel pit at Ryall. Three males were seen today and it is a mystery where they came from with the nearest populations being Clee Hill and the Forest of Dean. It’s regrettable that as a working site the precise location can’t be advertised. Thanks to Andy Warr for getting the first confirmed record for the county and for the photo .
15 July 2022 Some good work by Andy Warr has followed a colony of getting on for nearly 100 Scarce Blue-tailed Damselfly at Ryall including the fabulous orange immature female phase called Aurantiaca
11 July 2022 I might have been wondering where all the Emperors were a few days ago but having just been to the excellent Kemerton Bird hide which sits in a lake, I can tell you there were stacks there. Ideal to photograph as Great Crested and little Grebes pass amongst 6 egg laying female Emperors. All around and up the sides of the hide, larval cases hung like reserve trophies!
09 July 2022 Some species might have seemed scarce today but others were busy keeping the next generation going like these Azure damselflies egg laying, en mass, at Feckenham
06 July 2022 The last of the damselflies to emerge, the Small Red-eyed is emerging now and some have been seen at Malvern by Roger Mason (Photo); near Feckenham and Hartlebury
15 Jun 2022 The first Brown Hawker was seen today at Upton Warren by Des Jennings (Ph below)
11 Jun 2022 It feels like the season is progressing when Common Darters start to show and the first was seen at Feckenham by Andy Warr. Note the straw coloured line in the legs which shows it isn’t a Ruddy Darter in which case they would be all black
10 Jun 2022 Showing quite early this year, the first emerald Damselfly was seen at Grafton Wood by John Tilt
07Jun 2022 The first Golden Ringed Dragonfly or rather its larval case was found in a wet flush in Wyre Forest today. Amazing how one of the largest dragonflies can live in damp sphagnum moss, and be able to hunt other creatures by stealth tactics
04 Jun 2022 It’s been a disappointing year for Clubtail emergences this year with the lowest count for 16 years. Hopefully it’s only a temporary blip. It is sometimes assumed that dragonflies can decide to emerge next year if the weather is poor but synchronised species like clubtails decide if they are to emerge in the previous autumn depending on their body weight condition. Cool weather can make freshly emerged individuals vulnerable to attack by spiders and scorpion flies
26 May 2022 Already the season has advanced enough to see our regular hawker, the Southern hawker emerging for the first time. This one seen by Keith Falconer at the Fold, Bransford
21 May 2022 Amongst the newly emerged Scarce Chasers at Hillditch was one that didn’t get away. It’s likely that this one died before the Scorpion fly got stuck in as they only go for carrion (Ph Mike Averill)
19 May 2022 The first Emperors were seen today at Westmancote, making this the earliest date since 2007. The huge mask or lower jaw is a giveaway (photo: John Chapman)
13 May 2022 The first record of a Broad-bodied Chaser is rather late this year. However several were seen by Carol Taylor and John Tilt whose photo this is, at Grafton Wood today
10 May 2022 There are four key species listed for Worcestershire, that characterise the county and one of those is the Four spotted Chaser. Definitely becoming more common over the last 10 years, the first one has been seen at Penny Hill, today by John Tilt. The shot below from 2016 at Penny Hill
30 Apr 2022 Another first appearance, on such a warm day, was this Beautiful Demoiselle, seen by Andrew Pitt on the Salwarpe at Upton Warren
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09 Nov 2022 The common Darter has been quoted as being less common than it was but this species really comes in to its own if there is late warm weather as in Indian summer. This year we are getting mild weather in to November and Common Darters seize the opportunity to pair up and lay eggs. Several pairs were seen at Feckenham today
24 Sep 2022 Two reasons for posting this shot from Andy Warr. Firstly It’s a super shot and the angle of the wings is unusual in a resting damselfly. Normally this rotation only occurs on the up wing stroke during flying, when there is no lift and it allows the wing to go up ready for the nest down stroke without catching the air
17 Sept 2022 Prospects of Willow Emerald being seen next year just got better as Des Jennings finds egg-laying scars at Fox Hollies Pool. This is the only type of breeding record for any species in the UK which is accepted where one of the normal stages of the life cycle are not present like pairing, egg laying, larvae or exuviae.
03 Sep 2022 We have been waiting for the much heralded Willow Emerald in Worcestershire for a while now, so how nice for long standing recorder Des Jennings to be the first one to see it. Des operates in the old Vice County area of N.E. Worcestershire and he found a male at Fox Hollies Park, Acocks Green. This means that we can no longer assume all Emerald Damselflies seen are Lestes sponsa. (Ph below Des Jennings)
06 Aug 2022 It’s not easy to identify flying dragonflies when all the markings appear as a blurr, but this super shot from Madi Farmer captures a Southern Hawker in flight and you can easily see it’s a male. Note how they tuck their front legs neatly behind the head
29 July 2022 Below average rainfall this year plus record high temperatures have dried shallow wetlands including scrapes at Feckenham, Ponds at Hartlebury Common and Penny Hill Quarry. At Penny Hill The two species capable of sitting out the dry spell, Emerald Damselfly and Ruddy Darter were very evident today. Their ability to use vegetation to conceal eggs until the Autumn rains enables them to overcome these dry periods where other species can’t.
12 July 2022 There are a growing number of new housing developments with water storage systems (Sustainable Urban Drainage Systems). These could be a new aquatic area for wildlife but do they hold water all the time. If you see a new one please let me know if it does. An example of a new one is the Warndon 6 on the Evesham road from Warndon / M5 roundabout. The photo below is a new site at Eckington
12 July 2022 John Lane and his remarkable garden in Malvern, has done it again with the first Migrant Hawker recorded this year. Not surprisingly the second earliest date in recent years
09 July 2022 Today was perfect for dragonfly activity with light winds; wall to wall sun and 25°C, yet some species were noticeably secretive. Only saw 2 Emperors all day and very few Banded Demoiselles at Eckington. Can it be too hot, well it can but it wasn’t anything like that today
22 Jun 2022 Exactly the same first date as last year for the Ruddy Darter. There were many at the Croome river. This one has obviously been out for several days and even looks a bit like a Red –Veined darter, but note the waisted abdomen and the all black legs
15 Jun 2022 Are we to get any Lesser Emperors this year was the question? This was answered by Andy who saw and photographed this one at Ripple. The green eyes and blue saddle distinguish it from our normal blue Emperor
12 Jun 2022 Exciting news from a gravel pit near Upton today as Andy Warr discovers a substantial colony of Scarce Blue tailed Damselflies mating and egg laying so at last positive proof that they have bred in Worcs. It is most likely that they all emerged there too
10 June 2022 Following the finding of the first larval case at Croome earlier this year of a Hairy Dragonfly, we have a record of a female (below), thanks to Keith Falconer; not previously seen there. Further proof that the site continues to be occupied by this new species
04 Jun 2022 Although the Clubtailed Dragonfly hasn’t done so well this year at Bewdley, the White-legged Damselfly on the other hand has, with over 100 emerging so far at the same 100 metre site.
28 May 2022 It’s been a while since we had a Worcestershire Dragonfly Field meeting so it was really good to meet at Ripple to explore the wonderful wetland that has been left after gravel extraction. 25 people attended and although cool weather made it slow work we did get 14 species. Unfortunately the Hairy Dragonfly didn’t show until 15:30 when most people had drifted away. Clubtails and Scarce Chasers were seen though, sitting along the river bank edit.
Female Clubtail below from Eden Tanner 
21 May 2022 Also seen for the first time today at Croome and Hillditch Pool, were the first Scarce Chasers (Ph Andy Warr)
21 May 2022 It’s a busy time for first emergers and it was the time of Black-tailed skimmers to show themselves at Ripple. Photo Andy Warr
21 May 2022 It is really good to see the Hairy Dragonfly at the bottom end of the Croome River again for the third year running. This and the newly established Scarce Chasers make this a very important site (Ph Andy Warr)
20 May 2022 With new life there are the inevitable failures and this Large Red has obviously failed to emerge for some reason; winds, rain etc. but there is always something to take advantage like this Scorpion fly - Photo Martin Chapman
13 May 2022 There have been a few sightings today of a White-legged damselfly from Witley Court and Ripple, which is quite early for the species.
06 May 2022 River temperatures are reaching 15°C, now and that is a trigger for the Clubtail Dragonflies to change from an aquatic life to an aerial one. The first adult male was seen at Bewdley today
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30 April 2022 One day makes a lot of difference and while yesterday maximum temperatures were 11°C, today we reached 18°C, which meant a flush of freshly emerged damselflies down at Ripple where Andy Warr reported four new species
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Azure Damselfly (Ph- Andy Warr)
Blue-tailed Damselfly (Ph- Andy Warr)
15 April 2022 A sudden change in the weather running in to Easter meant temperatures rose to over 20°C and so a few Large Red Damselflies have been seen. The first one reported was from Richard Horton at Penny Hill
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Common Blue Damselfly (Ph- Andy Warr)
Red-eyed damselfly (Ph- Andy Warr)
21 April 2022 A Banded Demoiselle, was seen at Upton Warren today, by Andrew Pitt and that was the second earliest in recent years.
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Dragonfly Buzz
Jared Tibbetts had a surprise on the 8th Jan 2020, when he found what looked like 2 Blue-tailed damselflies at Hagley. But it was later when Andy Warr was checking twitter feeds, that he realised that they were not our common Blue-tailed Damselflies at all but the Asian/African species Ischnura senegalensis. This is often the most likely damselfly to be found at that time of year, especially as it was in a garden centre aquarium building. The Larvae are brought in with pond weeds and although they might emerge, they find themselves in the dead of Winter so no hope of surviving. It’s another species for Worcestershire but we can’t add it to the list considering how it got here. ( Ph Jared Tibbetts)
Dragonfly sightings 180 million years ago in Worcestershire
In 1845 fossils were found in an old quarry near Strensham that had a layer of clays ideal for showing the fine detail of insect wings. One of these early damselflies was Liassophlebiidae withersi and a fore-wing of the species was found. It’s usually only the wings that get preserved but in the same quarry a specimen of an abdomen was found which has been named as Liassophlebiidae clavigaster but without more being found of this second specimen, this description can only be tentative. This was a very significant find as not only was it one of the very earliest ancestors of modern damselflies but it proved that the often quoted extinction between the Triassic and Jurassic periods didn't include some creatures at least in that location. Remember that Worcestershire at the time was at the latitude of where Cuba is now.....20° North
In 1845 fossils were found in an old quarry near Strensham that had a layer of clays ideal for showing the fine detail of insect wings. One of these early damselflies was Liassophlebiidae withersi and a fore-wing of the species was found. It’s usually only the wings that get preserved but in the same quarry a specimen of an abdomen was found which has been named as Liassophlebiidae clavigaster but without more being found of this second specimen, this description can only be tentative. This was a very significant find as not only was it one of the very earliest ancestors of modern damselflies but it proved that the often quoted extinction between the Triassic and Jurassic periods didn't include some creatures at least in that location. Remember that Worcestershire at the time was at the latitude of where Cuba is now.....20° North
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A new study – by the University of Exeter and the UK Centre for Ecology & Hydrology – used data from the British Dragonfly Society to see if the arrival of the new species-The Small Red-eyed Damselfly has caused native damselflies and dragonflies to decline.
The results showed most native dragonflies and damselflies were either found more often or were unchanged in areas colonised by the small red-eyed damselfly. However, two damselfly species might have been negatively affected, and more research is needed to investigate this. https://resjournals.onlinelibrary.wiley.com/doi/10.1111/icad.12630?af=R |
There is a new book called The Atlas of the Dragonflies and Damselflies of West and Central Asia, covering for the first time, a detailed overview of the distribution of the damselflies and dragonflies (Odonata) of West and Central Asia, an area covering nearly 8 million km². So if you are looking beyond Europe towards Asia this could be for you. Although not claiming to be an ID book there are 175 species covered with a photo and distribution map.
Bio-inspired robotics: learning from dragonflies
Bioinspired robotic models have developed a dual catapult system for activating the dragonfly nymph’s extendable mask. It had been thought that hydraulic pressure was responsible for operating the mask but this doesn’t have the power to operate the very rapid extension. Acting like a catapult, an internal elastic structure in the dragonfly’s head is activated, that is held by a muscle like a spring. According to the Kiel-based researchers, these types of systems are widespread in the animal kingdom and can be found, for example, in grasshoppers, cicadas or Mantis shrimp. Here
Bioinspired robotic models have developed a dual catapult system for activating the dragonfly nymph’s extendable mask. It had been thought that hydraulic pressure was responsible for operating the mask but this doesn’t have the power to operate the very rapid extension. Acting like a catapult, an internal elastic structure in the dragonfly’s head is activated, that is held by a muscle like a spring. According to the Kiel-based researchers, these types of systems are widespread in the animal kingdom and can be found, for example, in grasshoppers, cicadas or Mantis shrimp. Here
Its true Damselflies consume thousands of sometimes annoying insects
A study led by the University of Turku, Finland has attempted the difficult exercise of assessing how many insects, damselflies consume. Using four species, C. hastulatum, C. pulchellum and E. cyathigerum & C lunulatum they found that over two months they consumed on average 870 gms of insects, mainly chironimids. Each species consumed 29-66 % of their body weight during its life. Their body weights being 33.9 to 35.4 mg’s
Although obviously doing a great job it was pointed out that this was only a small proportion of the insects available and that dragonflies would be the next area of research.
https://doi.org/10.1111/1365-2656.13184
A study led by the University of Turku, Finland has attempted the difficult exercise of assessing how many insects, damselflies consume. Using four species, C. hastulatum, C. pulchellum and E. cyathigerum & C lunulatum they found that over two months they consumed on average 870 gms of insects, mainly chironimids. Each species consumed 29-66 % of their body weight during its life. Their body weights being 33.9 to 35.4 mg’s
Although obviously doing a great job it was pointed out that this was only a small proportion of the insects available and that dragonflies would be the next area of research.
https://doi.org/10.1111/1365-2656.13184
New Proposal about how dragonfly wings developed
Most Insect classification is based on wing morphology but dragonflies have always caused disagreement as to how they formed. A new approach is put forward by Trueman & Rowe claiming to solve several long standing issues. They reinforce some theories that the dragonfly ancestor began when wings developed from two fused legs originally from a crustacean. Later damselflies developed and from them true dragonflies see here
Most Insect classification is based on wing morphology but dragonflies have always caused disagreement as to how they formed. A new approach is put forward by Trueman & Rowe claiming to solve several long standing issues. They reinforce some theories that the dragonfly ancestor began when wings developed from two fused legs originally from a crustacean. Later damselflies developed and from them true dragonflies see here
ED: All good fun but when is someone going to come up with an APP that identifies dragonflies from a wing scan?
Someday, cicadas and dragonflies might save your sight. The key to this power lies in their wings, which are coated with a forest of tiny pointed pillars that impale and kill bacterial cells unlucky enough to land on them. Now, scientists report they have replicated these antibacterial nanopillars on synthetic polymers that are being developed to restore vision. See report in New Scientist
When did you last see a pair of Brown Hawkers in the Cop position?
The sight of lone females, egg laying isn’t unusual but apparently mating is not often seen and if work in Germany is anything to go on it may happen around sunrise. Researchers in Germany (Matutinal Mating in Aeshna grandis-Odonatologica Dec 2017 p 207-226) found that males would search for perched females around sunrise even it was wet and cool. This may be natural selection to pick the hardiest and keenest males apparently! We have very few sightings in Worcs so be on the lookout next year if you are an early bird!
The sight of lone females, egg laying isn’t unusual but apparently mating is not often seen and if work in Germany is anything to go on it may happen around sunrise. Researchers in Germany (Matutinal Mating in Aeshna grandis-Odonatologica Dec 2017 p 207-226) found that males would search for perched females around sunrise even it was wet and cool. This may be natural selection to pick the hardiest and keenest males apparently! We have very few sightings in Worcs so be on the lookout next year if you are an early bird!
Dragonflies are model for the latest drone design. Rather than using rotors this mimic uses four wings just like a dragonfly. Skeeter, as it is called, will have four independently flapping wings, a camera and microphone, and will fly at up to 45 kmph
Dragonfly brains predict the path of their prey showing skills previously thought to be only achieved by mammals
New research from Australia and Sweden has shown how a dragonfly's brain anticipates the movement of its prey, enabling it to hunt successfully. This knowledge could lead to innovations in fields such as robot vision. The Swedish-Australian collaboration resulted in the discovery of brain cells (neurons) in the dragonfly Hemicordulia that enables them to predicatively pursue and catch their flying prey. These neurons make it possible to focus on a small object that moves over a complex background, similarly to how humans can track and catch a ball, even when that ball is moving against the backdrop of a cheering crowd
New research from Australia and Sweden has shown how a dragonfly's brain anticipates the movement of its prey, enabling it to hunt successfully. This knowledge could lead to innovations in fields such as robot vision. The Swedish-Australian collaboration resulted in the discovery of brain cells (neurons) in the dragonfly Hemicordulia that enables them to predicatively pursue and catch their flying prey. These neurons make it possible to focus on a small object that moves over a complex background, similarly to how humans can track and catch a ball, even when that ball is moving against the backdrop of a cheering crowd
Female Dragonflies take a dive to avoid male advances
Reported in the New Scientist female dragonflies have been noted as using extreme tactics to get rid of unwanted suitors: they drop out the sky and then pretend to be dead.
Rassim Khelifa from the University of Zurich, Switzerland, witnessed the behaviour for the first time in the moorland (Common) hawker dragonfly (Aeshna juncea). While collecting their larvae in the Swiss Alps, he watched a female crash-dive to the ground while being pursued by a male. The female then lay motionless on her back. As soon as her suitor flew away, the female took off again. It is probably related to general evasion of predator tactics
Reported in the New Scientist female dragonflies have been noted as using extreme tactics to get rid of unwanted suitors: they drop out the sky and then pretend to be dead.
Rassim Khelifa from the University of Zurich, Switzerland, witnessed the behaviour for the first time in the moorland (Common) hawker dragonfly (Aeshna juncea). While collecting their larvae in the Swiss Alps, he watched a female crash-dive to the ground while being pursued by a male. The female then lay motionless on her back. As soon as her suitor flew away, the female took off again. It is probably related to general evasion of predator tactics
Scent of a Damselfly helps males choose a mate.
To date there is no evidence that damselflies use any sense other than vision (and tactile stimuli) in mate searching and sex recognition. However the results of research in Italy has shown that male damselflies of Ischnura elegans can distinguish between males & females using chemical clues. This is particularly significant where you find a number of colour forms as with this species and it is thought the antennae pick up the clues.
Frati F, Piersanti S, Conti E, Rebora M,Salerno G (2015) Scent of a Dragonfly: Sex Recognition in a Polymorphic Coenagrionid. PLoSONE 10(8): e0136697. doi:10.1371/journal.pone.0136697
To date there is no evidence that damselflies use any sense other than vision (and tactile stimuli) in mate searching and sex recognition. However the results of research in Italy has shown that male damselflies of Ischnura elegans can distinguish between males & females using chemical clues. This is particularly significant where you find a number of colour forms as with this species and it is thought the antennae pick up the clues.
Frati F, Piersanti S, Conti E, Rebora M,Salerno G (2015) Scent of a Dragonfly: Sex Recognition in a Polymorphic Coenagrionid. PLoSONE 10(8): e0136697. doi:10.1371/journal.pone.0136697
A Dragonfly is the world’s greatest traveller: The Globeskimmer (Pantala flavescens) has been known to be a long distance traveller for some time and for this reason has been chosen to be the logo of the World Dragonfly Association.
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Recent genetic work has proved that the species that occurs on all continents except the Antarctic are so close that they have all derived from the same lineage. Most dragonflies and insects never move far from their own pond leading to differences over geological time. Madagascar which has been an island for over 30 million years shows how creatures develop in localised ways as over 90% of dragonfly species are endemic ( only found there). Pantala probably moves 3000 miles in one go around the Indian Ocean and It shows that it easily beats the Monarch Butterfly, the other great travelling insect Citation: Troast D, Suhling F, Jinguji H, Sahlén G, Ware J (2016) A Global Population Genetic Study of Pantala flavescens. PLoS ONE 11(3): e0148949. doi:10.1371/journal
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How much does a Dragonfly eat: more work on the Globe Skimmer by a Japanese University has found that a typical Pantala eats about 14mg’s of food a day equating to about 185 midge like insects. If you think what the population of this worldwide species is then the amount of insects eaten each year is staggering and good reason to encourage dragonflies in mosquito areas (Odonatologica vol 44 No 3 2015)
_There is a new look website for the Worldwide Dragonfly Association click here This new site holds a lot more information about dragonflies around the world
Have you seen the book about the wildlife of the Malvern Hills and the associated common land, published by Pisces and follows the same format as the Wyre Forest Book. With one of the first ever records for the dragonfly database being in Malvern, dragonflies certainly feature in the book.
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First Sightings for each species each year
