Tag Archives: Falco peregrinus

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!

The Isle of Wight, Part 2

My first view of the Needles, at the western tip of the Isle of Wight, was a long time ago when I flew round them in a light aircraft. The weather was much like it is below and it was quite a spectacle!

The Needles looking across to the Isle of Purbeck. Old Harry Rocks are the thin sliver of white chalk in the distance at 11 o’clock from the lighthouse

I’d heard it said that the Needles were at one time joined to the Old Harry Rocks at the southern end of Studland Bay, around 15 miles away on the Isle of Purbeck. I’d thought it entirely possible but never had it confirmed. And then just after I took this photograph I overheard a very knowledgeable old gentleman telling his companion all about the local geology, so I stood close by and earwigged the conservation.

As you can see, the Needles are made of limestone and apparently they were once a single strip of rock with a gap in the middle from which a single calcareous stack protruded, known as ‘The Needle‘. And then in the 18th century a storm caused a collapse which resulted in the Needles of today.

But before that, Old Harry and the Needles were a single limestone structure and the Isle of Wight wasn’t an Isle, and the Solent – the stretch of sea which separates the Isle of Wight from the mainland – was the River Solent. But around 4-5000 years ago a storm breached the limestone wall and the River Solent became a seaway overnight and the inhabitants of the Isle of Wight were cast adrift on a new island. And interestingly, all the rivers on the mainland from Poole Harbour in the west eastwards to Portsmouth: the Meon, Itchen, Test, Avon, Frome and Piddle all flow southward, and those on the Isle of Wight: the Eastern Yar, Western Yar, Newtown, Wootton Creek and Medina all flow northward, and they all drained into the River Solent.

Pyramidal orchid – Anacamptis pyramidalis

The terrain all around the Needles is chalk downland which has very characteristic flora and fauna, amongst which is the pyramidal orchid and this lone flower was lurking at the edge of The Needles carpark. It thrives on the chalk downs to such a degree that it has been chosen as the county flower of the Isle of Wight. In the air high over the car park was a peregrine falcon (Falco peregrinus, Dansk: vandrefalk) but I didn’t have a telephoto lens with me on this trip, so alas, no pictures. From the car park it’s about a mile to walk to The Needles themselves and on a sunny day it’s a terrific walk, the views are magnificent.

To the east, north and west the air was full of falcons, songbirds, bees and butterflies, and when we got to the very end there was a historic naval gun emplacement. In WWII the gun guarded the Solent and the strategically important ports of Poole, Southampton and Portsmouth against enemy shipping, and just over the top of the cliff from the gun emplacement was a test site for missile engines which had been hewn from the rock – a hangover from the Cold War. The whole thing was fascinating, geologically, biologically and historically!

Teasels – Dipsacus fullonum

Whilst trying to photograph a stonechat which was darting around next to the path I noticed these teasels which were still sporting their downy purple flowers. I have lots of photographs of the dried out brown seedheads of teasels after they’ve flowered but but I’ve been after a good one of the flowers themselves. And I think this is the best backdrop I could have found, looking out across the Solent towards the New Forest on a sunny day.

Also flitting around in the chalky grassland were hundreds of chalkhill blue butterflies. It was a very windy day and I think the butterflies may have been staying down low becausse of the wind, preferring to be stationary rather than risk being blown away. Consequently they were fairly easy to get close to:

Chalkhill blue male (Lysandra coridon)

I absolutely love blue butterflies. In fact anything living and blue – insects, flowers, fish reptiles – blue seems to convey a unique beauty on a creature, so to see so many of these blues was a real pleasure. And the chalkhill blue is a big butterfly too, with a wingspan of 33-40mm.

One of the curious facts about blue butterflies is that some of them are actually brown, and with chalkhills as with common blues, the females are brown:

The female chalkhill blue. She’s brown, not blue, but still a beauty!

Chalkhill blues mating, the brown female is on the left

Apparently this year was a particularly good one for the chalkhill blue. Despite being a devastating one for most other butterfly species in the UK, there were huge numbers of breeding chalkhills recorded in their traditional territories, and in my humble opinion that’s very good news indeed.

The view along the north of the island looking east towards Southampton, with yachts racing toward us

The geology of this part of the south coast is remarkable too. Limestone was formed at the bottom of oceans by the compaction of dead shellfish over millions of years, so it may seem odd to find it at the top of the cliffs. Or indeed whole cliffs made of it. There is a clue to how this happened in the cliff below, which is looking round to the southeast from The Needles, in which there are clearly delineated strata in the rock running upwards from left to right at around 45 degrees. The reason for angled strata is that in this part of the world tectonic shifts have concertinad the rock strata all the way from the east of England along the south coast as far as Dorset to the west forcing them upwards.

This folding of the rock means that in the east the rock is relatively young but the deepest, oldest, layers have been exposed in Dorset around the town of Lyme Regis. So the region around Lyme is referred to as the ‘Jurassic Coast’. Of which more in a subsequent post.

All those flocking waders

The Cambridgeshire Fens can be a bleak and windswept part of the world as the winter months descend, and today it was very bleak and very windswept, but it’s a great location for getting out and seeing some exciting and scarce wildlife.


A small flock of lapwing and golden plover over Burwell Fen

For those of you who don’t know the Fens they’re characterised by wide open flatness and big skies. They were originally under water but were drained by Dutch engineers in the 17th and 18th centuries to leave high quality arable land. The soil is extremely rich in organic material which gives the soil the rich black colour evident in the picture above.

I set off there on Saturday with my friend David because there had been a report on the Cambridge Bird Club website of short eared owls (Asio flammeus, Dansk: mosehornugle) in the vicinity. After wending our way through Swaffham Prior and Reach we rocked up at Tubney Fen where we sat in a new National Trust hide overlooking a new pond with new reed beds which had four coots (Aythya fuligula, Dansk: blishøne) and a pair of mute swans (Cygnus olor, Dansk: knopsvane) paddling on it. And no other signs of life whatsoever.

As we watched, the mute swans took off and looped round low right in front of us and landed back on the water. At least one of them landed on the water in the spectacular and graceful way that mute swans do. The other one crash landed on the ground just short of the water and after regaining its equilibrium stood looking highly indignant but managed to retain it’s dignity in a way that only a mute swan could in those circumstances. We hoped it wasn’t injured but it looked to be suffering from little more than damaged pride.

After another five minutes sat in the hide the lack of further activity and the low temperature caused us to move on, and on the way back to the car we spotted eight whooper swans in a field several hundred meters away. The whooper (Cygnus cygnus, Dansk: sangsvane) is a winter migrant to the UK and a very scarce breeder, usually less than ten pairs a year will breed here. It’s a similar size to the mute swan but it’s neck is straighter and the beak is straight with a black tip and pale yellow base. Their breeding territory is in the high Arctic and they migrate south as far as Africa for the winter.


A family unit of eight whooper swans – two adults with white plumage and the charateristic yellow beak and six cygnets with pale grey/white plumage and without the yellow beak

We decided to move on to Burwell Fen from Tubney Fen and on the way we were considerably closer to the swans so we stopped for another look. And as we looked David noticed that a pale brown stripe in an adjacent field was in fact a flock of golden plovers (Pluvialis apricaria, Dansk: hjejle) and lapwings (Vanellus vanellus, Dansk:  vibe). When I was a kid I spent a fair amount of time out and about exploring the countryside and huge flocks of lapwing consisting of hundreds and possibly thousands of birds were a fairly common sight. But their numbers have been dwindling for decades and these days I’m pleased if I see more than twenty. A carrion crow was getting agitated in the tree beyond the plovers because a buzzard (Buteo buteo, Dansk: musvåge) was perched there too, but the crow wouldn’t get too close and the buzzard just sat tight and ignored it. There turned out to be 243 lapwing in this flock and for me that alone justified the trip.


Around 10% of the lapwing in our flock of 243

There were also several hundred golden plover. As we watched another even bigger flock joined them and when they were flushed into the air we could see another flock as big again in the middle distance and beyond that another that was enormous. So we estimated that between these flocks there were several thousand birds. It was a amazing sight.

The flocks of waders eventually settled so we made off further into the Fen, pausing to gaze at a group of roe deer (Capreolus capreolus) relaxing in a field:


These very well camouflaged roe deer didn’t seem at all perturbed by our presence

As we watched the deer, a sparrowhawk (Accipiter nisus, Dansk: spurvehøg) quartered the field and then a peregrine falcon (Falco peregrinus, Dansk: vandrefalk) swooped past car, travelling with the customary haste that species is renowned for.

Arriving eventually at a car park, we continued on foot over a bridge where several kestrels (Falco tinnunculus, Dansk: tårnfalk) were quartering all the fields around and almost immediately spotted a short eared owl. It was perched on a fence post in the middle of the adjacent field and I initially mistook it for a little owl because I was looking at it from front-on and I could only see the top half, but when we saw it through David’s spotting scope we could clearly see it was of the short eared variety.

Short eared owl hunting rodents the easy way, not wasting any energy

As a result of the inclement weather, low light and strong wind, and only having a 300mm lens I couldn’t get any good photographs, but it’s unmistakeably a short eared owl, so I’m happy.

We saw various small songbirds such as chaffinch (Fringilla coelebs,  Dansk: bogfinke) and goldfinch (Carduelis carduelis, Dansk: stillits), five bird of prey species, whooper swans, and countless thousands of golden plover and lapwing. So despite the cold it was fine way to spend a Saturday morning.