Wednesday, 2 October 2013

Nature Notes 2008


A Paean to Teal
Male teal
by Lip Kee, Singapore
Before I started birdwatching three & a half years ago, I only knew of teal along with widgeon as ducks that hunters stalked, shot and ate - I assumed they must be big fat birds like mallards. In bird guides they were described and illustrated as very definite colours - chestnut, green and yellow etc.
I first saw real teal within the last three years, and then initially only as far-off black spots out on the water that other birdwatchers had pointed out. Then I saw some myself but still from a long way away - I could just see their yellow rear patch to identify them and that was all, any closer approach and they were gone.
So it came as something of a revelation to see them at very close quarters on the Bristol Ornithological Club trip to Farlington Marshes, and then close again at Kings Weston Lane reservoir last week. How different from bird guide illustrations! Far from being definite colours, they conjure up words like ethereal, satiny, silvery...  Every different angle and quality of light casts them differently - now the head seems quite pale, then it suddenly appears as flashing patterns of red and green. Their bodies shimmer with subtle colours and the yellow patches fade and flash back to prominence -  like the exquisite members of some Diaghilev ballet, Schehezerades of the water...

Geology musings
Because it's so dark and wet and blowy, and probably because I've started a geology course on understanding sedimentary rocks, I've been doing a little musing....
....Imagine that human history finished right now (you can give or take a few hundred years) - what would the geological record look like in say 5 or 10 million years? That's about the shortest geological period in which to get a meaningful view, amounting to a sedimentary section a few inches thick. What would happen to cities? Skyscapers? Allow for about 1mm of compacted sediment being laid down every 100 years.
Here are some images to conjure with:
- In 5 million years there would be some movement of continents, but not a huge amount.
- If another ice age occurred, glaciation could fell a city, and chunks of building would be carried along, to drop out as erratic boulders hundreds of miles away. Then they’d be subject to further erosion and deposition...
- I can imagine a single skinny conglomerate layer worldwide, representing all our civilisation, and containing little shards of plastic detritus, and weird chemical compounds.
- I wonder what would happen to those new artificial islands the Arabs are developing, full of skyscapers etc.? There’s not a lot of extreme weather there, like hurricanes. Seas rising would perhaps start their downfall - it wouldn’t take too much erosion to wash away the foundations. When they fell in the sea they would form lovely new coral colonies...
Anyone got any other images?

Ernest Thompson Seton
'Wolf scratching':
ETS life study
I was very moved last night to watch a programme narrated by David Attenborough, about Ernest Thompson Seton, the 19th to 20th century American writer and naturalist.
I have mentioned him once before in this group when we were discussing favourite birds I think – I said I’d like to be a sociable rook, and had been inspired in this by ETS’s writing about the rooks’ life from their point of view, plus his lovely drawings. I read his books extensively as a child but never seemed to have heard him mentioned since, and it gave me a real start to see the original Victorian-style cover of ‘Wild Animals I Have Known’ on the screen – so familiar to me yet not seen for so long.
I was thinking about him when Des Bowring started his thread about which books had inspired people to become interested in nature. I didn’t respond because, I now realise, the books that had absolutely gripped me were ones about what it was like to BE a wild creature and this seemed somehow childish and frivolous in light of Des’ question. The Kipling ‘Mowgli’ books fell into this category, and till I was almost a teenager I was counting down, ‘I’ve still got 8-7-6…3 years left to become a jungle child like Mowgli and learn those skills and live like that…’ (I think Mowgli left the jungle when he was 15?).
Otherwise I knew little about ETS, and it was great to find out how his intense love of the American wilderness and the animals who inhabited it was so influential in changing public awareness, forming the first national parks, and creating the start of an environmentalist/ecological movement there. And only now, 100 years on, has his view that a wilderness needs its balance of predators as well as prey started coming to fruition (specifically the wolf which was the core of Attenborough’s programme and the epiphany causing ETS’ change from hunter to preservationist). Maybe more people and children will start reading his books again?

by Des Bowring
Walking the River Thames
I just spent a couple of days walking the River Thames and gravel lakes around Letchlade. It’s odd after being used to cliff paths to walk on the level mile after mile, as well as the dream-like quality of being alone by a smoothly swift-flowing river in Spring. There seemed to be a wren in almost every bush, singing so loud it was almost deafening. Many reed buntings and chaffinches, but few warblers, and I only saw one heron.
- Blackbird: On Monday dusk I sat by the river and listened to a  blackbird practice an unusual song phrase over and over. Sometimes he gave it jazzy twists, sometimes he transposed it into a different key.
- Swans: At dusk I saw a lovely sight - two pairs of young swans ‘mirroring’each others' dips, ducks and
Angry mute swan
by Mike Pennington
nuzzles etc, sometimes in parallel and sometimes as a mirror. Next day I saw some fine examples of ‘threat’ behaviour, with the male’s neck laid back so far and the head pulled down so low it was almost invisible behind the raised wings, and paddling hard enough to raise a bow wave.
- Rooks: I’ve seen such a mass of rookeries on this trip, as well as on a previous one passing though Salisbury Plain to Lulworth Cove. Are they doing particularly well this year? My Bed & Breakfast bedroom in Lechlade looked out one, and I admired the elegant curve the rooks took through the branches as they swooped down and up from their nests. An elderly gent told me that the height of their nests is supposed to foretell the weather - the higher the better the summer. If so, then some rookeries give a concensus on fair, while others are a mixed bag and hedging their bets.
- Terns: there were quite a few terns flying up and down the river. Now tell me this: what do terns have against the south west? I’ve not seen a tern along the coast in south or west Wales, Somerset, Devon, Cornwall or Dorset. The times I have, it’s been along the Grand Union Canal in and up from London, on the Isle of Wight crossing, and here.
- Swallow: I had the closest view I’ve had yet of a swallow, sitting placidly on a post and allowing one to fully appreciate the beauty of its gunmetal blue back glistening in the sunshine.
- Fish: I saw a large flotilla of largish long fish sized between about 30-40cm (Thames trout? Chub?) cruising silently a couple of inches below the water surface, remaining there as long as I watched. It was strange because though I was constantly looking into the river, I otherwise didn’t see other fish and only saw a few splashes.
- Fritillary flowers: In one riverside meadow field I saw some unusual reddish flowers in the distance. On
Snake's Head Fritillaries
by Tony Hisgett, Birmingham
inspection they turned out to be a whole area of fritillaries with the largest blooms I’ve ever seen - larger than any garden centre display. Can the botanists shed any light on this? (Snake's Head Fritillaries - as the water meadows fringing the river flood, the bulbs are washed downstream to propagate new areas)
- Hare: I saw a fine hare startling two curlews grazing in a field, as it lolloped between them.
- Agression: You can really feel the hormones in the air at this time of year, the forceful singing and the aggression. On my first evening a group of cows with their calves on a field with the footpath through it had a go at me. Next day having a drink at a riverside pub a domestic goose drove me from the garden. And on the river path one wren stayed so fearlessly close as I walked past its bush that I thought it would have a go at me too!

Swifts - fooling the eye
Swifts are here! About 10 so far, not singing, but if flight can express joy that's what they're showing in abundance. Saw a stunning manoeuvre: a pair close-coupled and moving in tandem did a sudden perfect turn
'on the spot'. They also have this strange ability like Spitfires, to apparently appear out of nowhere and then disappear again into empty sky - how do they do that? Is it a *Derren Brown effect? (* British illusionist)

Swift, by Ken Billington

Swifts - fooling the eye
Since my recent 'Derren Brown' comment on how swifts deceive the eye as they fly, I have been studying the flight of our local Filton swifts to try and understand how. This is what I have noticed:
- They bank swiftly from side to side. This means they often present their slimmest profile to view.
- They frequently do that little shimmer of the wings.
- They can turn on a sixpence and zoom off at massive speed in another direction.
The combination means that often they present their slimmest profile and do a little shimmer, which totally fools the eye - blurring their existence and rendering them momentarily almost invisible. If they then immediately zoom away in another direction, your eye has lost them and it's as though they had disappeared!
Why do they bank and shimmer? Is it to fool prey, or predators, or both, or to shake moisture from their wings? It struck me with the recent thunderstorm and rain, what it means to stay up in all that weather permanently. It really makes sense of their extra size and sturdiness compared with swallows and martins - you gotta be strong!

Darwin and Engels
Having finished and much enjoyed Darwin's 'The Expression of the Emotions in Man and Animals ' I was intrigued in the introduction to learn that Engels read it and while appreciating the contents, despised the way it was written - 'typically English', he said. I assume he meant that it is written in a very informal,  non-academic way, fully admitting where there are gaps in evidence, giving many examples from observing his own children, and even having notes saying things like, 'Prof Soandso has pointed out the weakness in my argument here, and I must agree with him.'
Now it's a long time since I read Marx and Engels who very much changed my way of thinking, and whom I admire for putting 'who profits?' into historical analysis and thus actually making sense of history instead of a meaningless list of monarchs and battles. And I can't remember how 'pseudo-scientifically' it was written, but I feel if their works had been written more in the Darwin style it would have been harder for the Soviets to turn it into ironclad dogma with an apparently scientific basis. Because of course there wasn't such a basis - it was the authors' own ideas and observations, pertinent though they may have been.
It was also an eye-opener to learn how the anthropologist Margaret Mead and her followers villified Darwin's work (unscientifically) because of certain concerns they had about its use politically (how Soviet!). Yet now I understand Mead herself is discredited in many ways - for instance, she was a mere 23 when she went to Samoa, and the Samoans admitted to later workers (with a better grasp of the language and culture) that they had fed her a lot of stories of the sort they could see she wanted to hear - that'll be the juicy sexy ones I expect.
Sorry, this isn't strictly wildlife, just wanted to get that off my chest.

South Pembrokeshire coast
I have been walking the South Pembrokeshire coast for 4 days west of Manorbier, from Stackpole towards Milford Haven.
- Firstly, I encountered an extraordinary huge caterpillar and I’m longing to know what it is: it was 2 ½ inches long, as thick as my finger, brilliant green and regularly banded with thin velvet black stripes with small white spots. It was perservering on the sandy coast path though there was inviting vegetation on each side, but not making too good a job of it as it kept tilting or flopping rather helplessly sideways. (Wasn’t identified - possibly an escaped rarity)
- Peregrines along the coast: My first evening I saw what I thought what was swifts mobbing a kestrel. A day later I saw what I thought was a buzzard and kestrel again being mobbed by martins and swallows - then realised they were both peregrines. Later again I saw what I thought was a buzzard on a post: big, upright pose - but no, again it was a peregrine; as I approached it flew off, went ito a steep dive down the cliff, and soared up fast almost vertically to a favoured perch on the cliff face.I watched a larger bird take a small prey to what could have been a nest site - a smooth, well-worn little sheltered platform on an inaccessible cliff; while the ‘smaller’ ‘browner’ birds I had mistaken for kestrels flew around as it ate. On my last day very early in the morning I saw a threesome flying together east above the beach. Obviously I was watching family groups, though whether the same one on different sections of coast, or different ones I don’t know. After doing peregrine watches on the Downs you’d think I’d have all this identification off pat, but it is always different on one’s own without expert eyes to help!
- Funnel webs on the cliff path from Freshwater Bay to Stackpole: many of the gorse bushes displayed complex gauze web structures, all leading back to a funnel if inspected closely. Some of the attaching margins were covered or formed of a shiny membrane that glinted in the sun; and I also noticed that though the sun was hot enough to have burned away any dew on surrounding vegetation, some of the webs held what appeared to be big dew drops on the gauze, adding to the sparkling appearance. One funnel was in its purest form: like a narrow-necked, wide-bottomed beaker of gauze, delicately attached at three points to three gorse sprigs.
- The cliffs west from Stackpole are where the Old Red Sandstone turns to Carboniferous. From a level
by Alan Rolfe
plateau on top they drop smooth and vertical about 150-200 feet - worse than vertical in many places where they actually slope inwards about 5 degrees. Stretches for climbers alternate with stretches left for breeding birds - and you can see why the birds need protection 'cos on a hot, still Saturday these awe-inspiring cliffs were infested with climbers. I asked one group how they rated them for difficulty on a UK scale and they said - very hard - smooth, very few holds, overhangs... Progressing west there are more heartstopping sights for the vertiginously challenged: Horseman’s Leap where a stack has separated from the main cliffs by just two or three feet - but look down and those three feet are sheer from top to roiling sea at the bottom... A natural arch where the underside is thin and cut perfectly level horizontally about 40 feet above the sea, looking like a guillotine or drawbridge... Places where from the narrowest gap the sea has carved a deep narrow isosceles triangle inland, isosceles in plan but again completely vertical sides... Savage grandeur... Beautiful limstone-meadow flora.
The clifftop heathland from St Govans towards Milford Haven was full of a lovely selection of small birds: whinchat, stonechat, wheatear, linnet, goldfinch, pippet; and gatekeeper, meadow brown and other butterflies in profusion as well as an occasional red admiral, marbled white, and blue. Chough sightings increased from scattered couples grazing to family groups in playful flight; and a local birder said a bit further west Dartford warblers had been breeding for the first time in the last couple of years.

by Des Bowring
Yesterday there were a pair of crows eating apples on next door's tree. They attacked the fruit with extraordinary - frightening - force, great pecking blows that sent showers of the fruit flesh about.

‘E O Wilson’s ‘Sociobiology’
I have just finished reading a great science classic, E O Wilson’s ‘Sociobiology’, 1980 abridged edition (‘Sociobiology: the systematic study of the biological basis of all social behaviour.’). This is one of those extraordinary books whose main tenets and observations have pervaded our/society’s minds so completely that one does not recognise the source until one reads the original - like Freud and the concept of the unconscious. One of the book’s most significant observations to me, is how throughout the animal kingdom there are intrinsic conflicts between the needs and desires of the individual, the family, and the groups containing the family and individual. The torments mankind suffers because of these conflicts are not ours alone, nor are they in any way necessarily reconcilable (except at a spiritual level) - much though we and our politicians would often like to hope otherwise.
Another striking thing is how one can be reading an analysis of a creature as humble as a flatworm or other invertebrate and thinking, ‘Oh my God, that’s just like humans.’ Lower creatures have some sophisticated behaviour, and we are so often not alone in our reactions... Anyway, I recommend it to those who like this sort of thing.

Fennel engineering
by Alvesgaspar
I have been very struck and impressed this year, by two fennel plants growing in my garden. Their slender stems grow up to about 6' tall and by the later summer are weighted by substantial flower / seed heads. However they survive every storm going without bending or breaking - a miracle of natural engineering. Just now I cut their stems down and was able to study their structure in more detail. The stems are segmented like bamboo, hollow and pith-lined in section. Perhaps the most impressive thing is to tug the cut stems at the base. They do not thicken there in any appreciable way, but one can feel that they are welded deeply into the root structure, and neither stem nor root responds at all to heavy pulling. Amazing! Ove Arup Engineers, eat your heart out!

Starling display
I saw a nice sight from my loft a couple of days ago, on a sunny, windy late afternoon. A flock of about thirty starlings gradually increased to about fifty and collected on the roof opposite. They flew up and around in a cloud, and then suddenly dispersed to the large bare ash tree behind the roofs where they distributed themselves evenly throughout the outer branches, looking like leaves or bunches of ash keys. Every now and then one would drop away like a falling leaf, and seemingly, as the wind gusted strongly, a whole group were 'blown' out of the tree and away together out of view.

This morning a crow was perched on a roof ridge opposite, holding some carrion; it held the flesh firmly down with one foot while tearing off pieces with its strong beak, and head and neck. I was very intrigued to see how similar this behaviour was not only to a larger raptor like an eagle, but also say to a lion or tiger, holding down prey with a big paw and tearing off flesh with powerful teeth, jaws and head.

Sparrows in the park
In my local park on the sunny afternoon this Wednesday, sparrow song was loudly in evidence. Particularly on the south-facing boundary made up of high bramble and ivy thickets, the sparrows made a positive 'wall of sound' of wonderful zest and vigour.

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