Category Archives: Cherry Hinton Lime Kiln

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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The fastest falcon

In fact, not just the fastest falcon, the fastest creature on the planet. Under its own steam, with a little assistance from gravity, the peregrine falcon (Falco peregrinus, Dansk: vandrefalk) can reach up to 150mph (240km/hr) in a stoop. And that is a staggering number!

Cherry Hinton lies on the southern edge of Cambridge, and on the southern edge of Cherry Hinton is an ancient chalk pit known as the ‘Lime Kiln’. The Lime Kiln is a very interesting place, it’s a very large hole in the ground where the chalk has been quarried for millenia and converted to lime for building and agriculture. It’s lined with white chalk cliffs and it’s now a nature reserve managed by the local Wildlife Trust, and there’s nothing quite like it within a radius of many miles of Cambridge.


In June I had heard a rumour that a pair of peregrine falcons were nesting in the Lime Kiln. This was big news because until very recently I only saw them on the more wild and woolly parts of the UK coast where they hunt pigeons and seabirds. But in the last few years I’ve seen them fairly regularly, if infrequently, over the fields and fens of Cambridgeshire. I think the Lime Kiln must be the only rock face resembling the peregrine’s natural habitat within a 50 mile radius, which makes it even more remarkable that they found it and nested there.


To have a pair actually nesting on the edge of Cambridge was very exciting, so I paid a visit to the Lime Kiln to see if I could see them for myself. I’d been advised by a friend of the approximate location so it was fairly easy to find them sitting on the chalk face in full view, making occasional sorties into the air.

The peregrine is the fastest creature when it stoops on its prey, but it is not the fastest bird in level flight. That accolade goes to the wonderfully named ‘white throated needletail’ (Hirundapus caudacutus), which is a species of swift and can reach speeds of up to around 70mph (112km/hr) on the flat.


The peregrine’s wingspan is around 1m and the female weighs up to 1.1kg. So a bird colliding with a 1.1kg attacker travelling at 150mph is invariably going to come off second best. These awesome predators have other adaptations to protect themselves during high speed descents onto prey including a membrane which covers the eyes and baffles in the nostrils to prevent very high speed air flow from damaging their lungs.


The pair at the Lime Kiln have apparently nested there for the last three years and I believe that in their first year they raised one chick, the second year they got three away and this year they only managed one due to the dreadful weather through the springtime. But five chicks in three years is a fine tally.


I saw them over the Lime Kiln on several visits and watched them scaring the bejeezus out of the local pigeons, not during a a serious hunt, just a high speed chase on the flat, but the pigeons took it seriously and showed a surprising turn of speed too. I also saw a falcon in a stoop and another with prey in its talons which it passed to its beak whilst on the wing, which is behaviour more normally associated with the hobby.


These birds are magnificent and I’m hoping they return again to breed next year, and if they do I won’t be able to stop myself sharing some more pictures with you!