Friday 14 November 2014

Damsels – down at the local




In my blog post of 13 September, I showcased some fairly flashy Cape York dragonflies (http://hdpphd.blogspot.com.au/2014/09/cape-dragonflies.html ). But you certainly don’t need to go to such far-flung places to see such diversity. Last weekend I saw two different dragonflies and a damselfly around the pool in my back yard! This is a salt-chlorine swimming pool, not a quiet reedy backyard pond, but it still manages to attract a surprising range of insects, spiders, lizards and birds (subject for another post sometime?).

On this occasion, there was a Blue Skimmer Orthetrum caledonicum (which will pose nicely for the camera), a Tau Emerald Hemicordulia tau (which are forever zipping about and are a real challenge for the 400 mm lens autofocusing), and a Common Flatwing Austroargiolestes icteromelas (which would have sat quietly were it not for the Tau chasing it away into the gloom of the surrounding shrubberies, never to be seen again).

The first two are very common dragonflies in Canberra (and throughout Australia for that matter), but it was the first time I’d ever seen a Common Flatwing (which is a damselfly). I had previously seen just one other flatwing – a Sydney Flatwing Austroargiolestes isabellae – beside Jinden Creek in the upper Shoalhaven Valley in January 2010.

A Blue Skimmer Orthetrum caledonicum (Libellulidae)
on the edge of my backyard swimming pool.


Tau Emeralds Hemicordulia tau (Hemicorduliidae) are usually seen in flight - this one over my backyard pool - rather than perched.  Note the legs are well tucked up against the body.


But this Tau Emerald Hemicordilia tau was perched and was the brightest I've seen
(perhaps newly emerged?). This was at Wedden Mountain National Park in central NSW.


A Common Flatwing Austroargiolestes icteromelas (Megapodagrionidae)
beside the pool briefly before being seen off by a Tau Emerald.


A Sydney Flatwing Austroargiolestes isabellae (Megapodagrionidae)
at Jinden Creek in the upper Shoalhaven Valley, NSW.


Both Saturday and Sunday of last weekend were warm, sunny, and not particularly windy, so my camera took me down to the dam at the local golf course, no more than a 400-metre walk from home.

Here there were the odd Blue Skimmer and Tau Emerald constantly patrolling the edges of the dam, but the fringing reeds and grasses, particularly in one secluded corner, were alive with small damselflies. The most common was probably the appropriately named Common Bluetail Ischnura heterosticta, but there were almost as many Red and Blue Damsels Xanthagrion erythroneurum.

The male Common Bluetails are quite stand out, their double-ended electric blue forms drifting about amongst the vegetation, intermittently settling on selected prominent perches. But there were many more females of the species about, probably something like four or more females to every male; they were less obvious in their drab colours, but very obvious in their intent to populate the dam with as many offspring as possible.

A male Common Bluetail Ischnura heterosticta (Coenagrionidae)

A female Common Bluetail Ischnura heterosticta (Coenagrionidae)
busy laying eggs along a decaying reed stem.


The male Red and Blue Damsels (is that an oxymoron, or just contemporary?) are even more striking. Interestingly, the males of this species outnumbered the females about two to one, and most were paired off, cruising the reed patch in tandem. In fact I never saw an un-paired female. When flying about like this, it’s hard to see who is taking the lead, but when the female starts laying eggs she is definitely the one in control. She’ll work her way down an emergent reed or twig and start laying a sequence of eggs along the submerged substrate. The male obligingly follows, but there was one occasion I witnessed where he had no physical support and was forced to remain airborne while she layed. This made me recall a trip to a friend’s place near Albury back in 2010 where I watched a laying female work her way further and further down a waterlogged twig until both she and the super-positioned male were submerged to a depth of about 10 cm.

A male Red and Blue Damsel Xanthagrion erythroneurum (Coenagrionidae)

A mated pair of Red and Blue Damsels Xanthagrion erythroneurum (Coenagrionidae)

A mated pair of Red and Blue Damsels Xanthagrion erythroneurum (Coenagrionidae)
briefly in the 'wheel' position. 

A pair of Red and Blue Damsels Xanthagrion erythroneurum (Coenagrionidae)
- they stay in tandem while the female lays her eggs.

But sometimes the male has nowhere to perch while she's busy at it!


Somewhat surprisingly, I never saw a single paired-up duo of Common Bluetails. Rather, if a male did show interest in a settled female, either quietly perched or actively laying on a bit of decaying reed, she would cut short his prospective attentions by dissuading him with a brief gossamer fluttering of her wings.  Perhaps they don't stay together long in the tandem formation, or maybe they had been paired up earlier in the day and I just missed it. 

So I was briefly excited when I did see a tandem pair, the male of which was topped and tailed in blue. But on looking at the photos it turned out that this was in fact a pair of Eastern Billabongflies Austroagrion watsoni, the only ones I saw there that day. Indeed the only ones I’ve ever seen!

A mating pair of Eastern Billabongflies Austroagrion watsoni (Coenagrionidae) in the 'wheel' position


After the Common Bluetails and Red and Blue Damsels, the Blue Ringtails Austrolestes annulosus were next most common. These seemed to be a bit more “off by themselves” and I never saw a paired couplet – or even a female as far as I know - and they were very obviously different, much bluer overall when ‘lit upon the end of a reed stem.

A Blue Ringtail Austrolestes annulosus (Lestidae)


There was another species I was expecting to see - the Aurora Bluetail Ischnura aurora. Three years previously, again in November and at exactly the same spot, I had first encountered this species when there were several individuals amongst the many Common Bluetails. They are a very small and delicate damselfly with a very attractive colour scheme in orange, green and blue. I spent quite a while on the lookout for these and eventually saw just the one, just briefly – hence the poor quality of the single photo I got. [I also saw these at Bowra in April this year – see Bowra non birds post - http://hdpphd.blogspot.com.au/2014/05/bowra-non-birds.html .]

A male Aurora Bluetail Ischnura aurora (Coenagrionidae)
surprisingly, the only one I saw at the dam that day.


I’m left wondering what conditions produced the abundance of Red and Blue Damsels this year (yet none that I saw in 2011) but so few Aurora Bluetails. And what will happen as this season progresses? It is still early after all, with the whole of summer yet to come…




Family Lestidae
These damselflies are medium to large. The three non-endemic Australian genera include the Dusky Spreadwing, ten ringtails, and three reedlings. The Blue Ringtail occurs in ponds, riverine pools and lakes across much of the southern half of Australia.

Family Megapodagrionidae
This is a family of small to very large damselflies which, uncharacteristically for damselfies, hold their wings spread out from the body when at rest. The 22 Australian species of Megapodagrionidae belong to five genera, of which four appear to be endemic, from eastern, northern, and south-western Australia. The Common Flatwing occurs in eastern Australia, frequenting rivers, streams and pools. The Sydney Flatwing is restricted to south-eastern New South Wales where it is associated with streams and boggy seepages.

Family Coenagrionidae
The Coenagrionidae has a world-wide distribution, with 13 genera occurring in Australia, of which two are endemic. Coenagrionid damselflies are often brightly coloured, with reds, blues and blacks predominating. The Red and Blue Damsel has an Australia-wide distribution and extends to New Zealand, New Caledonia and Fiji. It inhabits still or slow-moving water bodies. The Eastern Billabongfly occurs across much of eastern and northern Australia and is also in New Caledonia, frequenting both still and flowing waters. The Aurora and Common Bluetails are both inhabitants of sluggish or still waters and both have Australia-wide distributions, the former also occurring from India to the central Pacific, the latter from eastern Indonesia to the Pacific.

Family Hemicorduliidae
This is a widespread family (including Africa, Asia, Australia, the Pacific) of small to medium dragonflies, usually black or dark metallic with yellowish markings. The Tau Emerald is a common vagrant/nomadic species occurring across much of Australia except Cape York and Kimberley regions. They occur in a wide range of water bodies including rivers, lakes, pools, ponds and swamps.

Family Libellulidae
This is a large cosmopolitan family of ‘typical’ dragonflies. The Blue Skimmer is very common and occurs near a wide range of still and flowing waters Australia-wide, extending to Indonesia, New Guinea, and New Caledonia. 

5 comments:

  1. Brilliant stuff Harvey. I assume the new camera continues to deliver the goodies!

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    1. Dragonflies won't let you get close enough to use the macro lens (which is my new component) - all these photos were taken with the old trusty 100-400 lens. But yes, am still very much enjoying the macro lens.

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  2. Lovely. All those Coenagrionidae look just like ours. Reminds me I must submit my records to Faune Touraine for the Odonata atlas for this region that is being created.

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    1. Yep - a cosmopolitan family of look-alikes. I'm having to learn fast!

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  3. Very informative (and enjoyable) posting thanks Harvey. Love the photo of the Tau Emerald in flight!!

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