ID dragonfly please

[Rosebine]

Please could anyone help with ID of this dragonfly. It emerged on 24/08/2010 from our garden pond filled in June 2010. One photo is from 24/08 and other from next day. Due to wet and windy weather it was very battered so we gave a helping hand with a sheter on garden canes.

[GuyF]

Hi and welcome to the site!
This is a male Southern Hawker - Aeshna cyanea. Hopefully he emerged successfully but sadly I think the wings look like they haven't expanded properly, dragonflies are very vulnerable at this stage and it's easy for things to go wrong, well done for helping him out though!
Guy

[JRsbugs]

I'm not quite understanding how this can have emerged from a pond which was only filled in June this year? These take a lot longer than 2 months to mature, unless it crawled into the pond from a nearby pond.

I wonder if you could 'fill' us in a little more, I'm curious! I have had one laying eggs around my pond last year and this year, they are usually doing that around early September. My pond was only made at the end of July last year but I think these can take at least 2 years or more to mature.

Janet

[RoyW]

Originally Posted by JRsbugs

I'm not quite understanding how this can have emerged from a pond which was only filled in June this year? These take a lot longer than 2 months to mature, unless it crawled into the pond from a nearby pond.

Southern Hawker larvae do take 2-3 years to grow before they emerge in this country. I think that it is unlikely that a larva would crawl from one pond to another, but I guess that it could be possible (perhaps due to over crowding?).
If the filling date of June 2010 was not an error I think that the most likely explanation is that the larva was unknowingly introduced with plants added to the pond. Dragonfly & damselfly larva are often transported in this way - including a couple of damselflies in Kent recently that seem to be an Asian species, introduced to ponds with weed from Indonesia!

[JRsbugs]

Thanks Roy, it will be interesting to see what Rosebine says, then we might have a clearer picture one way or the other.

I wonder how the weed got here from Indonesia Roy, plant regualtions would require customs check before leaving the country unless it came in without and slipped through customs as many plants would.

Were the damselflies flying free? Same species, male and female? That could prove interesting!

[RoyW]

Originally Posted by JRsbugs

Thanks Roy, it will be interesting to see what Rosebine says, then we might have a clearer picture one way or the other.

Indeed - always best to find out from the people who are most likely to know the details!

Originally Posted by JRsbugs

I wonder how the weed got here from Indonesia Roy, plant regualtions would require customs check before leaving the country unless it came in without and slipped through customs as many plants would.

I know nothing about the import regulations, but there seems to be little doubt that everything was above board in this case. The manager of the aquarium where the weed came from in one of the cases was happy to say that most of the weed comes from Indonesia (there's no absolute proof that the weed concerned had definitely come from there though).

Originally Posted by JRsbugs

Were the damselflies flying free? Same species, male and female? That could prove interesting!

Both were immature females found by garden ponds (in Dartford & Orpington), and are probably Ischnura senegalensis. Males of this species could very easily be overlooked as Blue-tailed Damselflies (Ischnura elegans) - but I seriously doubt that a population could become established!
Anyway, this is off the original topic of the thread. The story of the second one can be read here if you are interested: Scarce Blue-tailed Damselfly, Kent - BirdForum

[JRsbugs]

Originally Posted by RoyW

Anyway, this is off the original topic of the thread. The story of the second one can be read here if you are interested: Scarce Blue-tailed Damselfly, Kent - BirdForum

I had an interesting long read, and found some more good dragonfly sites along the way!

I don't think Rosebine realised what would be started by their first post here! In a way, it might be still on topic.

[RoyW]

Originally Posted by JRsbugs

I don't think Rosebine realised what would be started by their first post here! In a way, it might be still on topic.

Yeah - apologies for that Rosebine!
Hopefully it's all of interest to you...

[Rosebine]

Originally Posted by GuyF

Hi and welcome to the site!
This is a male Southern Hawker - Aeshna cyanea. Hopefully he emerged successfully but sadly I think the wings look like they haven't expanded properly, dragonflies are very vulnerable at this stage and it's easy for things to go wrong, well done for helping him out though!
Guy

Thanks for the welcome and for the ID Guy. I was very uncertain, partly because of the supposed timescale from laying: but see responses below. At first I thought just of species that had been spotted visiting earlier in the summer. What would you highlight as the main distinguishing features?
Brian

[Rosebine]

Originally Posted by JRsbugs

I'm not quite understanding how this can have emerged from a pond which was only filled in June this year? These take a lot longer than 2 months to mature, unless it crawled into the pond from a nearby pond.

I wonder if you could 'fill' us in a little more, I'm curious! I have had one laying eggs around my pond last year and this year, they are usually doing that around early September. My pond was only made at the end of July last year but I think these can take at least 2 years or more to mature.

Janet

Thanks for your comments Janet and thanks also to Roy.
The pond was filled in June this year. There are no other ponds within half a mile which was one reason why we wanted to establish a pond for wildlife.
I thought first just in terms of the species observed flying/mating/laying from June onwards. I have tried to avoid foreign/invasive plant species but have purchased/cadged native plants and "seeded" the pond with samples of water/mud/debris from established ponds. Any larvae introduced must have been quite small at that stage (i.e. not noticed) but that is a possible explanation.
Incidentally I read that its eggs can be laid in "mossy bank" or "rotting wood" so pleased that both are habitats developing by design around the pond. However, how/when do the larvae then get into the water? Why would it emerge at this time of year? Is there another cycle of mating and egg laying to overwinter as eggs or larvae?