Tag Archives: black tailed skimmer

Life in the kiln

After a lengthy absence from the blogosphere I’m rushing to squeeze a last post in in 2013. It won’t be topical so I’m harping back to a visit to the Lime Kiln in Cherry Hinton, on the southern edge of Cambridge, from back in July. I posted from here earlier in the year about the resident peregrine falcons.

The main reason for this visit to the Lime Kiln was to see if the peregrines were still in residence. One of them appeared overhead and gave chase to a pigeon, but it was in level flight not in  a stoop so the pigeon made good its escape. It was more like a juvenile practice run than a serious attempt to make a kill. It seemed that the family group had dissipated and were no longer spending the whole day at the Lime Kiln.

A single peregrine falcon – Falco peregrinus – quatering the Lime Kiln

The peregrine is the worlds fastest bird, but only in a stoop, which is gravity assisted and more a controlled fall than real flying. In level flight it is comparatively cumbersome and not the fastest, that accolade goes to a species of swift called the ‘white throated needletail‘ (Hirundapus caudacutus) with recorded level flight speeds of around 70mph (112km/h).

Black tailed skimmer – Orthetrum cancellatum

The black tailed skimmer dragonfly was perched on the chalky ground and this is characteristic behaviour of the species. As the temperature rises above the mid 20’s Celsius he will perch on low vegetation instead. This one is an adult male, his blue abdomen is diagnostic and can only be confused with the male scarce chaser, but he lacks the dark patches at the proximal end of the wings which distinguish the scarce chaser.

The female and the immature skimmer have yellow bodies instead of the blue of the male:

Black tailed skimmer female

I’m not entirely certain whether this skimmer is a female or a juvenile, the juvenile has pale green eyes and the female has darker grey/brown eyes so I think this one is a female. Interestingly, this species is associated with water and males will fiercely defend a bankside territory against other competing males. But as far as I know there is no water in the Lime Kiln so the male above may be a non-territory holding male, and females do spend time away fom water. The black tailed skimmer feeds on a variety of prey and can show a preference for bigger prey species such as butterflies and grasshoppers. They’re ferocious, albeit short lived,  predators!

A pair of jackdaws, Corvus monedula

There were very few birds to be seen on this trip, it was at lunchtime on a very hot day (mid to high 20’s Celsius) so I think they may have been hunkering down in the shade, but I could hear a male whitethroat singing and a family of jackdaws were playing around on the white chalk cliff face.

Because of the relatively young age of the Lime Kiln, and possibly as a result of the unusual nature of the terrain, large areas of the floor are bare chalk and there are less plant species than there may be in a more conventional habitat.

Either a small skipper (Thymelicus sylvestris) or an Essex skipper (Thymelicus lineola) sipping nectar from a self heal flower

One of the wild flowers growing there is self heal (Prunella vulgaris). This skipper butterfly was perched on a self heal flower head but I’m not sure if it’s an Essex skipper or a small skipper, they are very similar in size, shape and colour, and alas I’m not sufficiently expert to unambiguously identify them.

I didn’t manage to publish this post in 2013 so it’s now my first post of 2014. So Happy New Year to everyone, may the next 12 months bring you health and happiness!

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Fenland safari

Wicken Fen is the largest remaining area of true fen in England and has survived because it has been conserved by encasing it in what is effectively a gigantic plastic bag. The earth on the Fen is waterlogged and if the bag weren’t there the water would simply drain away leaving very rich agricultural soils but none of the wildlife associated with fenland habitats. Another result of the water retention is that the Fen is 6-8 feet above the surrounding farmland and the earth literally shakes if you jump hard on the ground as it’s like a saturated sponge.

Because of the water the predominant habitats are reedbeds and waterways which is reflected in the wildlife. The Fen is so rich in wildlife that a hike around there is like a mini safari! I was there on a hot and sunny Sunday morning in June and wildlife of all sorts abounded. In particular the insects were very busy. This dragonfly had recently emerged from the larval stage as an adult and was sitting in the grass drying out before taking to the air.


Black tailed skimmer youngster preparing for it’s first flights

The young skimmer was on the edge of a path which ran alongside one of the lodes (man made water courses) and on the water opposite the skimmer were lily pads and sitting on one of them was a damselfly, warming itself up in the morning sunshine.


Red eyed damselfly (Erythromma najas) in beautiful repose on a lily pad, surrounded by reflections of the clouds

And of course, that time of year is the season for lurv for many creatures, including this pair of variable damseflies (Coenagrion pulchellum) which are in the process of mating. The male is the blue one and he is clasping the female by gripping the back of her head – the pronotum – whilst she has pressed her genitalia against his abdomen to receive the sperm.

As well the inscect diversity the unique habitat of the Fen is home to lots of beautiful plants and flowers, including this common spotted orchid. This orchid is indeed common and can be found in fens, marshes and other wetlands all over England, but is rare in Scotland. Common, or not, I think all orchids are spectacular flowers and it was really good to see them in such numbers on the Fen.

Common spotted orchid – Dactylorhiza fuchsi

Whilst I was busying myself trying to get photogrpahs of the dragons and orchids a kestrel (Falco tinnunculus, Dansk: tårnfalk) was busy overhead. But even better than that a hobby (Falco subbuteo, Dansk: lærkefalk) was on the hunt for dragonflies and small birds.

The hobby is a small falcon which can be seen in these parts in the summer and hunts low over farmland and reedbeds at phenomenal speed. It’s one of very few predators that can hunt swallows and swifts in flight. This one was doing exactly that and in the distance, a few hundred metres away were at least another two. So I guess it was a family and the chicks had recently fledged and the adults were showing them the ropes. So I whiled away a good half an hour watching their breathtaking aerobatic exploits!


Brimstone butterfly sipping nectar from a thistle flower

I did volutary work at Wicken for 3 years or so back around the turn of the Millenium. It was incredibly rewarding and a good opportunity for a lab-based sedentary person such as myself to get outside and do some donkey work under the sky. One of the projects I worked on back then was scrub clearance to create an area suitable for butterflies to breed. I went and had a look at it on this walk for the first time since I helped to create it and it was very different. The scrub we cleared had been replaced by less scrubby, more proper woodland, trees, and there was small open glades with grasses and wild flowers. Whilst I was in there I flushed a leveret, which is about the closest I’ve ever been to a wild hare, it had been sitting tight but made a run for it when I got just a tad too close – about 5m!

So I didn’t manage a picture of the hare but I did manage a shot of the brimstone butterfly above (Gonepteryx rhamni), which I thought was absolutely lovely, sitting on the purple flower and framed by the two grass stems. It was terribly obliging and let me move all round it to get the best angle for a portrait. So this is about the best shot and one I’m very pleased with. I hope you like it too!