jackdaw | The Naturephile

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!

‘If men had wings and black feathers, few of them would ever be clever enough to be crows’

Henry Ward Beecher
Clergyman, wit and abolitionist

I’m incarcerated at home at the moment, having been laid low with a seasonal Yuletide dose of coughing and spluttering so I haven’t been out observing, photographing and recording. Consequently, this is an ‘armchair post’ using old photographs, and constructed in the warmth of my dining room.

It has been inspired by the superb book ‘Corvus‘ by Esther Woolfson which describes living with many different birds including a rook and a magpie. If you haven’t yet read ‘Corvus‘, insist on a copy as a stocking filler this Christmas. It’s a beautiful book and is beautifully observed and written, one of the best nature books I’ve ever read. It’s very informative, funny and thought provoking and has led me to ponder the enduring relationship between humans and our wild creatures.

Jackdaw (Corvus monedula) sitting on a fence at the top of one of Bempton Cliffs in East Yorkshire

The title of this post ‘Rookes, Crowes and Choughes‘ uses archaic (Tudor) names for three of the Corvids (crow family), ‘choughs’ at that time also included jackdaws, as used in one of the most unpleasant pieces of legislation this country ever promulgated, viz, ‘Destruction of Crows, etc. Act 1532’. This act was passed under Henry VIII and was extended under the reign of Elizabeth I with promulgation of the ‘Preservation of grain Act, 1566’. Together known as the ‘Vermin Acts’, they established a legal framework for the destruction of animals and birds of all descriptions which were deemed a threat to food supplies:

‘…to doo and cause to be don as moche as hym or theym reasonably shall or may be to kill and utterly destroye all manner of Choughs, Crowes and Rookes comyng, abyding, bedying or hauntying (their property) upon peyne of grevous amerciaments to be levied by distress of the goodes and catalles of the Offendours.’

Landowners and workers were thereby legally compelled to actively destroy corvids and communities could be fined up to 20 shillings for failing to meet every year with the court appointed functionary to agree methods to achieve this goal. Along with corvids; kingfisher (believe it or not!) dipper, woodpecker, shag, hedgehog, mole, polecat, fox, rat, badger, weasel, stoat, otter, wild cat and pine marten were all slated for destruction. Kites and ravens fetched remuneration of one penny, a badger or fox, 1 shilling, on presentation of a head as proof of its demise. There was therefore a real financial gain to be made by killing these creatures. (It’s interesting to note how many of the proscribed species are currently the subject of protection legislation and conservation programs.)

Henry VIII didn’t stop there, he also passed the ‘Sumptuary Law’ of 1510, to be updated several times under Elizabeth I and known collectively as ‘The Statutes of Apparel’, which governed what could be worn by which social strata thus establishing a dress code regarding furs. Royalty could wear ermine and substrata of nobility could wear fox, otter etc… . Open season was thus declared on all furry animals.

However, and it is a big however, it is very easy to sit in the comfort of our centrally heated houses with our cars and our convenience stores, and pass glib judgement on people of those times. In the 16th century many harvests failed, early death from disease was a ubiquitous presence in the lives of all people, rich and poor, and one way to stave off such a fate was to eat healthily. Anything which threatened the food supply was therefore deemed vermin to be exterminated.

Religious factors also played a part, e.g. the otter’s diet was predominantly fish so their flesh was deemed by the church to be sufficiently fishy to be eaten for religious reasons instead of fish. God help the otter.

Carrion crow (Corvus corone) foraging for insects

The Vermin Acts were repealed in the mid 18th century but the practices they enforced only started to abate in the early to mid 20th century. That reflects a blood lust in humans which is anachronistic and indicative of a deeply unpleasant side of human nature that in our more enlightened times one may hope would find an outlet in other, more civilised, pursuits. So it is infinitely less problematic to pass judgement on the contemporary activities of hare coursers, badger baiters, egg collectors and misguided land stewards who still trap, poison and shoot red kites… or hen harriers etc., etc..

Back to crows, I have never subscribed to the point of view that members of the crow family are malevolent, wantonly destructive, or the harbingers of doom, as popular culture has historically portrayed them. And they certainly didn’t merit the attempts at wholesale extermination decreed for them in Tudor times.

I have often watched a couple of hundred rooks assemble in the mornings over Histon church amidst much cawing and general hubbub prior to disappearing en masse either as one, or in several smaller groups to feed in the local fields. I’ve also watched them wheeling in the air, playing tag, and indulging in what can best be described as pure devilment with their fellows and with other species of birds. They seem to possess a keen intelligence probably essential for a creature which lives socially in very close proximity to hundreds of others. The habit of all members of the corvid clan of caching food items, and then re-caching an item if they know they were watched first time round, indicates they have self awareness, awareness of others and coherent notions of the intent of others, and the ability to plan accordingly. And of course a very impressive memory.

Some of the Histon churchyard rooks (Corvus fruglilegus) taking to the air over a field to the north of Histon…
…and a single member of the mob on the ground looking for leatherjackets

It has also been demonstrated from a neuroanatomical standpoint that corvids have a high ‘encephalisation quotient’ – ratio of brain to body size – which renders them capable of higher levels of brain activity and I think that is adequately demonstrated by just watching them for a short time – 10 minutes observation has been enough to convince me on some occasions. ‘Bird brains’ they certainly aren’t!

The key point, it seems to me, is that scientific elucidation of relative intelligence levels between species is a somewhat redundant enterprise in many ways except than as part of an effort to change human perception, and hopefully educate people that random massacre of wild animals is not acceptable. I find it bizarre and shameful that it has ever been considered a reasonable occupation by humans to slaughter billions of animals for no particularly good reason. It is incumbent on all species to share our surroundings with each other in order to maintain a functioning and healthy place which we can justly claim to have managed in a sustainable way.

Blimey, there we are. Nothing like a dose of flu to catalyse a bit of pre-Christmas moralising. But I think if everyone were to read Esther Woolfsons ‘Corvus‘ it may impart a deeper understanding and respect for our fellow creatures in many more people. I think attitudes to other creatures are changing as the enormous amount of available information is accessed by people all over the world, but preserving wildlife will be a perpetual process as wildlife is squeezed into smaller and smaller pockets of true wilderness. I hope we can find a working balance.