Friday 28 May 2010
Where applicable, I will tag any new posts with odonata content so that a search can be used to filter out the feathers. If you do visit the birdy blog looking for dragonflies, please leave a comment. If I get enough comments, I will re-consider splitting again, but for now, I cannot justify the time running two blogs.
See you at Redgannet and thanks again.
Tuesday 23 February 2010
The first water I came to was the Victoria lily pond. Dragonflies seemed to like the raised edges of the lilies and 4 species were quickly found here.
The first appeared dark from most angles but when the light caught it a deep blue was apparent. Trolling through the photographs on http://www.africa-dragonfly.net/ I found a likely suspect in Black Percher Diplacodes lefebvrii It spent much of it’s time chasing off other odes that entered it’s airspace.
The second ode of the day nearly fell prey to a young Green-backed Heron. The large blotches at the base of the hindwing, the distinctive venation and the yellow/brown triangular windows give me confidence to name it as a Phantom Flutterer Rhyothemis semihyalina.
Number three was an Aeshnid which would not sit to have his picture taken. I believe that it was the Blue Emperor Anax imperator as the only blue aeshnid I can see evidence of in Mauritius. It was present at every body of water and moist patch that I encountered.
Number four stayed at some distance but the yellow spots on the side of it’s abdomen gave me cause to consider Ringed Cascader Zygonyx torridus as an initial identity. Z torridus does occur in Mauritius and I could find no other suitable candidate until I checked the female Black Percher which is a real possibility. Close by is a shallow grassy pond, fed and drained by a stream. On prominent points around the pond, 2 types of skimmer were conspicuous. One was an Orthetrum species. The very pinched abdomen at S3 &4 possibly indicated the Epaulet Skimmer Orthetrum chrysostigma, but I rather fancy Spectacled Skimmer Othetrum icteromelas for this one. It has a dark shoulder stripe and darker anterior margins to it’s pterostigma.
The other was the increasingly familiar Violet Dropwing Trithemis annulata. This ode has gained popularity with this blogger because of it’s ease of identification. But now I come to look at the last sections of it's abdomen..... can anyone confirm please?
Perched on debris in the draining stream was my one and only zygoptera of the day I have yet to identify this one. It seemed to prefer being very close to the water. It either perched on midstream debris or on low, overhanging grass.
Lastly, a poor observation of yet another frustrating Orthetrum. I noted the stripes on the thorax, but have nothing that compares to it in any information that I can find.
Tuesday 9 February 2010
On to Powai Lake within a 10 minute taxi-ride from the hotel. The water margins were choked with water hyacinth, but there seemed to be little in the way of odonata there. Instead, where the weeds had been pulled from the water and allowed to dry, Asian Amberwings, Brachythemis contaminata, were in position on prominent stalks. These were by far the most populous dragonfly of the day, seemingly abundant all around the lake.
A rough road ran alongside the lake leaving a stagnant ditch separating it from the main road. The ditch held damselflies with another C. coromandelianum and some of what I suspect to be a Pseudagrion sp possibly microcephalum (Pseudagrion microcephalum has been confirmed by Saurabh Sawant, the mastermind of Mumbai).
One was hovering over the water and I wondered if an in-flight shot might be possible. I was pleased with the way it came out. Two other damselflies have me stumped at the moment. My usual method is to consider females and young males or colour morphs of species already seen, but I can’t find a good match. They are currently labelled Mumbai ode 01 and Mumbai ode 02, but I feel they deserve better names than that (Saurabh Sawant again comes to the rescue with Ischnura senegalensis).
Odonata species; 4
Ceriagrion coromandelianum 4, Pseudagrion microcephalum 8, Ischnura senegalensis 2, Asian Amberwing Brachythemis contaminata 150
Thursday 28 January 2010
I started at the hotel at which we were staying, The Lord Charles at Somerset West. There is a small dam in the grounds which has plenty of lily pads and emergent growth around the edges.
First were some Common Bluetails, Iscnura senegalensis. This one was infested with mites.
Orthetrum species seem to abound in Cape Town and I was trying to get a handle on which was which.
Samways gives potentially 5 blue Orthetrum that might occur here and they are all reasonably common.
The individual above was especially dark and I believe this one to be a female.
A Common Citril, Ceriagrion glabrum was a pleasure to find.
A blue dropwing was seen at the edge of a pool and at the outflow to the river. The Navy and the Roundhook Dropwing appear pretty much identical and habitat and elevation should be considered. Pools and ponds for the Roundhook and rocky, shallow streams for the Navy. Above 700m for the Roundhook and below for the Navy. There is overlap, so they must be properly inspected in the hand which I have not yet tried to do.
Make you own mind up if you can.
At a picnic area near Paarl Rock, a small pond and garden kept me entertained for the afternoon.
I think I was high enough to call a Roundhook Dropwing, Trithemis dorsalis. In numbers was an acidic red dragonfly easily identified as the Red-veined Dropwing, Trithemis arteriosa.
Also present in large numbers was a small damselfly, the Swamp Bluet, Africallagma glaucum. Mostly it was found in the grass-like rushes beside a small stream in the gardens.
The late evening found me back at Heldeberg Nature Reserve. A small pond near the café here held my attention for quite some time. Again the Orthetrum proved confusing and the Red-veined Dropwing were abundant.
I managed a decent photo of a Two-striped Skimmer, Orthetrum Caffrum, though strictly speaking it appears to have four stripes. I suspect this may be a young male.
In the lawned area, a tiny pond has grasses surrounding it. Here was another Common Citril.
My favourite find of the week was a Boulder Hooktail, Paragomphus cognatus at Harold Porter Botanical Gardens, It was sitting on a rock beside a fynbos browned stream.It was not co-operative and I took a long while to get this shot. I chose my spot and sat to wait. As I sat, I noticed a Cape Sprite, Pseudagrion furcigerum on a mid-stream rock.
At a shallow pond further up the slope I had to get wet for another shot of a Swamp Bluet. I think that some bracketing is called for. I have been using extension tubes recently to allow super-macro focussing. The results are sometimes a little over-exposed.
Finally a Nomad, Sympetrum fonscolombii rounded out my odonata for Cape Town.
Tuesday 19 January 2010
Accra in Ghana however, is basking in 35C heat and the odonata are active through January.
There is a post on http://www.redgannet.blogspot.com/ for the bird fanciers and for those who prefer a more detailed commentary.
I am still stunted in my growth as a dragonfly spotter due to a lack of available field guides and would appreciate any assistance in identifying the following odes.
Around the African Regent Hotel in Accra, I found these three in a small patch of flowers at the entrance to the reception. Compared to the one pictured earlier from the scrubby area, this one shows a white stripe on the thorax bordered in black. Note the yellow on the upper legs opposed to plain black on the previous insect. The pterostygma is also yellow insted of black. Number three is slightly bluer than it appears in the photo. I wonder if it might be an Epaulet Skimmer, Orthetro Chrysostigma. The pterostigma seem a little elongated and I can see no sign of a yellow base to the hindwing for a perfect match, but the pinched abdomen makes me consider this as a possiblity. If it proves to be so, then no.2 is a good candidate for the female. They were only a few meters apart. Contestant number four shows from two different angles.
These last two were in the hills about 35 kms inland in the Aburi Botanical Gardens.Number five was found in a shaded area and the flash has washed out it's blue colour a little. Finally, number six was found close to no. five, but was favouring the dappled sunlit areas.
I have put out a few tentative feelers into the world of web, in the hope that somewhere out there, someone knows.
Here's hoping that someone finds this post and has some ideas.
Sunday 6 December 2009
My thanks go to Mr Ian Rocoto from http://odonata-malaysia.blogspot.com/ for his guiding hand and experienced eye.
Thanks also to Steve Covey who writes http://wiltshire-dragonfly-news.blogspot.com/ for the common name for Ceriagrion cerinorubellum
Singapore Botanic Gardens have some great habitat for dragonflies and in the limited time between the birding and before the onset of rain, I indulged myself.
There is a post on http://www.redgannet.blogspot.com/ if you need the logistics, or if you want to check out the birdies.
I found some old favourites as well as some new ones.Identification is still taking time. I am used to field guides for birds which are detailed in the extreme. The guides for odonata simply do not cut the mustard in comparison. Like birds, damselflies and dragonflies have sexual differences and age characteristics with regional variations too, not forgetting the larval stage. Most guides in this field show the male only with sketchy detail for differentiating between similar species. Websites are proving to be my best source of information, but they are limited by mostly being photographic, which cannot compete with detailed drawings that accentuate characteristics. I am currently working with my guide to Hong Kong, but managed to augment that with a small volume from the gardens gift shop.
Just inside the gate on Napier Road is the Marsh Garden. It is a small, shallow, still body of water with some emergent water plants and some weed. Around it are decorative plantings. At 07.00 when the sun began to rise, there were odonata already in position, waiting. The temperature only dropped to 28C last night so they should not take long to warm up.Neurothemis fluctuans, male.
Without an adequate guide, I took the first odes to be Russet Perchers, Neurothemis fulvia. Actually, they were Neurothemis fluctuans. I could not find a common name for them.Neurothemis fluctuans, young male
Neurothemis fluctuans, male
In an area given over to formal brick-built ponds with water lilies, some damselflies were stirring. On an unopened flower bud was a Pseudagrion microcephalum and on some floating lily leaves was an Common Bluetail, Ischnura senegalensis. I planned to return there later in the day to see if any would pose on an open flower.
Crimson Dropwing Trithemis aurora femaleOn Symphony Lake, the most obvious dragonflies were the Crimson Dropwing, Trithemis aurora. An Ictinogomphus decoratus, sat way out over the water on a horse-tail rush.
By the time I returned to the brick ponds, the Crimson Dropwings had arrived. They seemed to prefer the brick edges of the ponds as perches. On the lake, they had been using bank-side vegetation to sit out. As I had hoped, there were some Blue Dashers, Brachydiplex chalybea, perched on the open lilies making a beautiful picture.
I had promised myself a second look at the Marsh Garden before the rain set in. I was distracted on the way there by a male Rhodothemis rufa. I only had a very short time left, but managed a quick look at a medium-sized libellullid. I have named him Orthetrum testaceum, on advice from Ian. If I had known, I would have been looking for a tuft of setae on S2.
The other problem with odonata field guides is that they are usually incomplete. How can I definitively make an identification when I do not have the complete set to make a proper comparison?
I made a second visit to the gardens the next morning and spent most of my time in the Marsh Garden, but also managed to get to the Eco Pond which accounted for the Blue Percher, Diplacodes trivialis and the Green Skimmer, Orthetrum Sabina.
I had not impressed myself with my photography on the first day and wanted to return to see if I could do better. I found that for macro photography like this and when using the big lens at full throttle, locking the mirror up avoids the vibrations that have been plaguing me up ‘til now.
In the Marsh Garden, to my delight, I found a couple of new zygoptera. The first was Ceriagrion cerinorubellum. What a shame that such a beauty does not have a common name. Stop press. A comment comes from Steve Covey of http://wiltshire-dragonfly-news.blogspot.com/ the common name is Orange-tailed Marsh Dart Orange-tailed Midget Agriocnemis femina young male
Superficially similar, but much smaller was the Orange-tailed Midget, Agriocnemis femina Orange-tailed Midget Agriocnemis femina mature male.
A mature male and young male of this species were chasing each other through the bank-side rushes.
I warmed to the task of photographing the myriads of Neurothemis, still under the misapprehension that they were the fulvia sp. Only when I managed to find “A pocket guide Dragonflies of Peninsular Malaysia and Singapore” by A.G. Orr, did I notice that there were more Neurothemi than I had realised. By now it was raining and I had to return home that evening, so I am now poring over the photos trying to get good ID. I needed someone better aquainted with Singaporean odonata than I am to confirm their identities. To that end Ian Rocoto kindly perused the post and made suggestions that I am pleased to adopt.
Odonata species; 11
Common Bluetail Ischnura sengalensis 1, Pseudagrion microcephalum 1, Orange-tailed Marsh Dart Ceriagrion cerinorubellum 2, Orange-tailed Midget Agriocnemis femina 2.
Ictinogomphus decoratus 3, Blue Percher, Diplacodes trivialis 1, Green Skimmer, Orthetrum Sabina 2, Crimson Dropwing Trithemis aurora 30, Rhodothemis rufa 8, Orthetrum testaceum 2, Neurothemis fluctuans 20