̽��ֱ�� of Cambridge - ornithology

Poet, activist, bird watcher: exploring John Clare as nature writer

amb206 — Tue, 29 Aug 2017 08:00:00 +0000

̽��ֱ��poet John Clare (1793-1864) was a keen natural historian who knew the countryside in all its moods. His various jobs saw him labouring in farms and gardens; his gravestone remembers him as the ‘peasant poet’. Best known for his verse, Clare also wrote prose accounts of the plants and animals he observed in his native Northamptonshire.

In a foreword to the anthology, ̽��ֱ��Poetry of Birds, broadcaster and bird watcher Tim Dee notes that Clare wrote about 147 species of British wild birds “without any technical kit whatsoever”. His records contain 65 first descriptions of birds for Northamptonshire alone. ̽��ֱ��term ‘nature writing’ had yet to be coined in the early 1800s – but Clare was undoubtedly ahead of his time in the way that he wove his detailed observations of the natural world into his writing.

Dee is one of the speakers who will be talking about ‘Clare and the Art of Bird Watching’ at a symposium held on September 15, 2017 at the David Attenborough Building. ̽��ֱ��event is a collaboration between the Centre for John Clare Studies (English Faculty) and the Cambridge Conservation Initiative (CCI), itself a partnership between Cambridge ̽��ֱ�� and a cluster of conservation organisations.

CCI’s emerging programme on the arts, science and conservation is coordinated by Dr John Fanshawe, who has been seconded from Birdlife International. He explains: “Bringing together academics and practitioners is a core ambition of the community in the David Attenborough Building. John Clare, both as a poet and activist, is a perfect catalyst for exploring the close observation and in situ localism in which so much conservation is rooted.”

̽��ֱ��symposium will bring together literary scholars with ornithologists, nature writers and artists to consider what it means to observe and record birds. How, for example, does Clare look and watch, and how does he translate what he observes into words? How do today’s artists and writers respond to his work?

“ ̽��ֱ��idea is to raise questions about the act of bird watching, recording, understanding and classification, both in the early 19th century and the present day, dwelling in particular on the importance of localism and the distinctiveness of Clare’s environment and voice to his writing about birds,” says Dr Sarah Houghton-Walker from the Centre for John Clare Studies.

Academics speaking at the symposium include Dr Francesca MacKenney (Bristol), Dr Mina Gorji (Cambridge) and Dr Jos Smith ( ̽��ֱ�� of East Anglia). Participants will also hear from printmaker Carry Akroyd, textile artist Anita Bruce, and nature writers Alex Preston and Derek Niemann.

Clare’s work has long inspired artists whose work celebrates the natural world. Akroyd says: “John Clare is such a visual poet. He wrote outside, his eyes wide open to everything, and wrote inside with visual memory. He switches between a wide-angle bird’s eye-view of the landscape to hand-lens detail, and even now makes us see more.”

Birds soar through the lines of English poetry, but for Clare’s contemporaries they played an especially important symbolic role. “Shelley’s skylark is transcendentally a spirit. Keats’ nightingale is significant because it represents a sublime kind of not-knowing,” says Houghton-Walker.

Clare, however, insists on the real and the particular. He knows exactly how and where the birds he writes about nest; he knows how many eggs those birds lay; and he leaves behind a meticulous record of every detail, right down to the appearance of the markings on each egg.

“He’s intensely interested in habitat, behaviour and song, but also, increasingly, in the threats to birds from his fellow men. He insists on a vital accuracy in his descriptions which continue to astonish scientific natural historians, and yet produces poetry about birds which can claim to be some of the very best in the language,” says Houghton-Walker.

“Clare’s greatest achievement is the conjunction of scientific accuracy with what he calls ‘poetic feeling’. He possesses a depth of knowledge only achievable by painstaking observation of birds’ behaviour as it changes with the seasons. He scorns those poets who don’t take the time to watch and merely recycle, often inaccurate, poetic conventions.

His patient observation is rewarded with an intimate knowledge which is exhibited throughout his prose and poetry. He’s especially fascinated by nests – something that has been discussed by many critics.”

A determination to represent nature accurately led to struggles, too. Voicing his frustration at his inability adequately to transcribe the song of the nightingale, Clare wrote that “many of her notes are sounds that cannot be written the alphabet having no letters that can syllable the sounds”.

MacKenney says: “Clare was extraordinarily inventive in his attempts to get the sounds of birds into his own writing. But the ‘peasant-poet’ was not naive. Throughout his poetry Clare demonstrates a profound respect for the abiding 'mystery' of birds and their songs.”

Without binoculars and with nothing but his senses to rely on, Clare gave us some of the most compelling nature writing of the 19th century.

To illustrate some of the wonders of birds and their behaviour, the symposium will include a screening of ‘Murmuration X 10’, a short film by filmmaker Sarah Wood and Helen Macdonald, author of H is for Hawk, and a guided tour of the avian collection at the Museum of Zoology.

For more details and to book a place at the symposium ‘Clare and the Art of Bird Watching’ click here.

Inset image: Carry Akroyd's ‘Evening Crows’ linocut illustration from 'This Happy Spirit’.

At a symposium next month (15 September 2017) academics, artists and ornithologists will share their responses to the work of 19th-century poet John Clare, whose patient and accurate observations of birds in field and hedgerow continue to astonish and inspire.

Clare’s greatest achievement is the conjunction of scientific accuracy with what he calls ‘poetic feeling’. He possesses a depth of knowledge only achievable by painstaking observation of birds’ behaviour as it changes with the seasons.

Sarah Houghton-Walker

Carry Akroyd

'Swifts' lithograph from Carry Akroyd's 'Found in the Fields' series (detail)

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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How humans and wild birds collaborate to get precious resources of honey and wax

amb206 — Fri, 22 Jul 2016 08:17:43 +0000

Humans have trained a range of species to help them find food: examples are dogs, falcons and cormorants. These animals are domesticated or taught to cooperate by their owners. Human-animal collaboration in the wild is much rarer. But it has long been known that, in many parts of Africa, people and a species of wax-eating bird called the greater honeyguide work together to find wild bees’ nests which provide a valuable resource to them both.

Honeyguides give a special call to attract people’s attention, then fly from tree to tree to indicate the direction of a bees’ nest. We humans are useful collaborators to honeyguides because of our ability to subdue stinging bees with smoke and chop open their nest, providing wax for the honeyguide and honey for ourselves.

Experiments carried out in the Mozambican bush now show that this unique human-animal relationship has an extra dimension: not only do honeyguides use calls to solicit human partners, but humans use specialised calls to recruit birds’ assistance. Research in the Niassa National Reserve reveals that by using specialised calls to communicate and cooperate with each other, people and wild birds can significantly increase their chances of locating vital sources of calorie-laden food.

In a paper (Reciprocal signaling in honeyguide-human mutualism) published in Science today (22 July 2016), evolutionary biologist Dr Claire Spottiswoode ( ̽��ֱ�� of Cambridge and ̽��ֱ�� of Cape Town) and co-authors (conservationists Keith Begg and Dr Colleen Begg of the Niassa Carnivore Project) reveal that honeyguides are able to respond adaptively to specialised signals given by people seeking their collaboration, resulting in two-way communication between humans and wild birds.

This reciprocal relationship plays out in the wild and occurs without any conventional kind of ‘training’ or coercion. “What’s remarkable about the honeyguide-human relationship is that it involves free-living wild animals whose interactions with humans have probably evolved through natural selection, probably over the course of hundreds of thousands of years,” says Spottiswoode, a specialist in bird behavioural ecology in Africa.

“Thanks to the work in Kenya of Hussein Isack, who electrified me as an 11-year-old when I heard him speak in Cape Town, we’ve long known that people can increase their rate of finding bees’ nests by collaborating with honeyguides, sometimes following them for over a kilometre. Keith and Colleen Begg, who do wonderful conservation work in northern Mozambique, alerted me to the Yao people’s traditional practice of using a distinctive call which they believe helps them to recruit honeyguides. This was instantly intriguing – could these calls really be a mode of communication between humans and a wild animal?”

With the help of honey-hunters from the local Yao community, Spottiswoode carried out controlled experiments in Mozambique’s Niassa National Reserve to test whether the birds were able to distinguish the call from other human sounds, and so to respond to it appropriately. ̽��ֱ��‘honey-hunting call’ made by honey-hunters, and passed from generation to generation, is a loud trill followed by a short grunt: ‘brrr-hm’.

To discover whether honeyguides associate ‘brrr-hm’ with a specific meaning , Spottiswoode made recordings of this call and two kinds of ‘control’ sounds : arbitrary words called out by the honey-hunters and the calls of another bird species. When these sounds were played back in the wild during experimental honey-hunting trips, birds were much more likely respond to the ‘brrr-hm’ call made to attract them than they were to either of the other sounds.

“ ̽��ֱ��traditional ‘brrr-hm’ call increased the probability of being guided by a honeyguide from 33% to 66%, and the overall probability of being shown a bees’ nest from 16% to 54% compared to the control sounds. In other words, the ‘brrr-hm’ call more than tripled the chances of a successful interaction, yielding honey for the humans and wax for the bird,” says Spottiswoode.

“Intriguingly, people in other parts of Africa use very different sounds for the same purpose – for example, our colleague Brian Wood’s work has shown that Hadza honey-hunters in Tanzania make a melodious whistling sound to recruit honeyguides. We’d love to know whether honeyguides have learnt this language-like variation in human signals across Africa, allowing them to recognise good collaborators among the local people living alongside them.”

̽��ֱ��greater honeyguide is widely found in sub-Saharan Africa, where its unassuming brown plumage belies its complex interactions with other species. Its interactions with humans to obtain food are mutually beneficial, but to obtain care for its young it is a brutal exploiter of other birds.

“Like a cuckoo, it lays its eggs in the nests of other birds, and its chick hatches equipped with sharp hooks at the tips of its beak. Only a few days old, the young honeyguide uses these built-in weapons to kill its foster siblings as soon as they hatch,” says Spottiswoode. “So the greater honeyguide is a master of deception and exploitation as well as cooperation – a proper Jekyll and Hyde of the bird world.”

Human cooperation is crucial to honeyguides because bees’ nests are often hidden in inaccessible crevices high up in trees – and honeybees sting ferociously. Therefore the honeyguide waits while an expert human undertakes the dangerous tasks of subduing the bees (by smoking them out using a flaming bundle of twigs and leaves hoisted high into the tree) and extracting the honey from within, usually by felling the entire tree. There is no competition for the prize: the honey-hunters harvest the honey and honeyguides devour the wax combs left behind.

Co-author Dr Colleen Begg adds: “ ̽��ֱ��Niassa National Reserve is as much about people as it is about wildlife, and this is really exemplified by these human-honeyguide interactions that have been forged over thousands of years of coexistence. While many people consider wilderness not to have people in it, at Niassa people are an essential part of the landscape.”

This foraging partnership was recorded in print as early as 1588, when a Portuguese missionary in what is now Mozambique observed a small brown bird slipping into his church to nibble his wax candles. He described how this bird had another remarkable habit: it led men to bees’ nests by calling and flying from tree to tree. Once the nest was located, he wrote in his account of life on the eastern African coast in the 17^th century, Ethiopia Oriental, the men harvested the honey and the bird fed on the wax.

“What João dos Santos described was what we now call a mutualism between species. Mutualisms are crucial everywhere in nature, but to our knowledge, the only comparable foraging partnership between wild animals and our own species involves free-living dolphins who chase schools of mullet into fishermen’s nets and in so doing manage to catch more for themselves. It would be fascinating to know whether dolphins respond to special calls made by fishermen, as Pliny the Elder asserted nearly two thousand years ago,” says Spottiswoode.

“Back in Africa, we’re fascinated by the evolution of the honeyguide-human mutualism and, as a next step, we want to test whether young honeyguides learn to recognise local human signals, creating a mosaic of honeyguide cultural variation that reflects that of their human partners. Sadly, the mutualism has already vanished from many parts of Africa. ̽��ֱ��world is a richer place for wildernesses like Niassa where this astonishing example of human-animal cooperation still thrives.”

̽��ֱ��project was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) in the UK and the DST-NRF Centre of Excellence at the FitzPatrick Institute in South Africa.

For further information on this and other projects go to www.africancuckoos.com and www.niassalion.org

Inset images: Yao honey-hunter Orlando Yassene harvests honeycombs from a wild bees’ nest in the Niassa National Reserve, Mozambique (Claire Spottiswoode); Yao honey-hunter Orlando Yassene holds a female greater honeyguide temporarily captured for research in the Niassa National Reserve, Mozambique (Claire Spottiswoode); Yao honey-hunter Orlando Yassene chops open a bees’ nest in a felled tree in the Niassa National Reserve, Mozambique (Claire Spottiswoode); Yao honey-hunter Orlando Yassene holds a wax comb (honeyguide food) from a wild bees’ nest harvested in the Niassa National Reserve, Mozambique (Claire Spottiswoode); Claire Spottiswoode interviewing honey-hunter Issufo "Kambunga" Jaime (Mbumba Marufo).

By following honeyguides, a species of bird, people in Africa are able to locate bees’ nests to harvest honey. Research now reveals that humans use special calls to solicit the help of honeyguides and that honeyguides actively recruit appropriate human partners. This relationship is a rare example of cooperation between humans and free-living animals.

What’s remarkable about the honeyguide-human relationship is that it involves free-living wild animals whose interactions with humans have probably evolved through natural selection, probably over the course of hundreds of thousands of years.

Claire Spottiswoode

How honeyguide birds talk to people

Claire Spottiswoode

Yao honey-hunter Orlando Yassene holds a male greater honeyguide temporarily captured for research in the Niassa National Reserve, Mozambique.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

̽��ֱ��owl and the wind turbine: how stealth feathers could help reduce noise pollution

amb206 — Wed, 09 Sep 2015 13:54:14 +0000

Scroll to the end of the article to listen to the podcast.

Owls fly silently: not all species of owl but those species that rely on stealth in hunting small animals. People have known this for hundreds of years but until recently no-one has understood quite how these magical birds manage to swoop undetected on their scurrying prey.

̽��ֱ��puzzle of how the wings of certain species of owls are adapted to minimise the sound that their wings make has been solved by a partnership between researchers at the ̽��ֱ�� of Cambridge and two institutions in the USA.

̽��ֱ��key to the puzzle lies in the intricate structure of owls’ feathers – and especially the plumage on the trailing edge of their wings.

̽��ֱ��researchers have now been able to replicate this structure by producing a prototype surface (patented in 2014) which has potential applications in wind turbines and a wide range of fans. Its use could significantly reduce the noise generated by these products.

An especially promising end-use for the surface is for on-shore wind turbines which are heavily ‘braked’ to reduce noise pollution. ̽��ֱ��braking makes the turbines less efficient.

̽��ֱ��story began in 2010 when Dr Justin Jaworksi, then a researcher in the Department of Applied Mathematics and Theoretical Physics (DAMTP) at Cambridge ̽��ֱ��, decided to look in detail at the structure of owls’ wings.

At DAMTP, Jaworski (who is now at Lehigh ̽��ֱ��) worked with Professor Nigel Peake, a specialist in aeroacoustics known for his work on aircraft, to identify how owls’ wings differed from those of other birds.

They found three key differences. ̽��ֱ��first difference, unrelated to silent flight, is that owls’ wings are have a serrated leading edge in a way that enables them to plunge steeply downwards and then take off again.

̽��ֱ��other two differences combine to enable owls to fly stealthily so that they can hear their prey without it hearing them. “ ̽��ֱ��feathers on the upper wing surface have a particularly detailed and complex micro-structure with layer upon layer of interleaved barbs and hairs,” said Peake.

Much of the noise from wings – whether the wing of bird, plane or fan – originates at the trailing edge where the air passing over the wing surface becomes suddenly turbulent.

Owls have a neat solution to this problem. “At the trailing edge of their wings, owl feathers produce a flexible and porous fringe which reduces air turbulence by smoothing the passage of air,” said Peake.

No other species of bird possesses these features. Even more significantly, species of owl (such as fish owls) not requiring an acoustic stealth advantage do not possess them either.

To understand how the features unique to owl wings contribute to soundlessness, and in order to replicate the surfaces created, Jaworski and Peake have been collaborating with Professors William Devenport at Virginia Tech and Stewart Glegg at Florida Atlantic ̽��ֱ�� in a project funded by the US Office of Naval Research.

“We used advanced mathematical tools in a wind tunnel to show that the role of the fringe on owls’ wings is to negate something called the ‘Flowes Williams and Hall effect’. ̽��ֱ��porous elastic fringe filaments are a much softer ‘sound scatterer’ than a sharp rigid edge,” said Peake.

̽��ֱ��role of the complex feather structure is more of a mystery but the collaborators have been able, to some extent, to replicate its effect in the laboratory. “What appears to be crucial is the way that the fine hairs form a ‘canopy’ perhaps shielding the basal surface of the wing from pressure fluctuations in the turbulent air flow,” said Peake.

" ̽��ֱ��whole project has been very exciting. We’ve been able to use advanced mathematics to understand an amazing natural phenomenon, which then inspired us to develop a practical engineering solution to a really challenging noise pollution problem."

̽��ֱ��intricate structure of owl’s wings was noted more than 300 years ago by Francis Willughby (1635 to 1672), the polymath who compiled one of the world’s first comprehensive and analytical ornithologies. Several species of owl feature in Willughby’s Ornithologia libri tres which was published by his more famous friend and colleague John Ray (1627 to 1705).

Willughby studied at Trinity College, Cambridge, where the Wren Library holds a copy of the ornithology he authored. ̽��ֱ��lavishly produced volume contains dozens of plates showing birds categorised by their characteristics. ̽��ֱ��accompanying text reveals Willughby’s passionate interest in the wonders of the natural world.

Of the eagle-owl, Willughby writes: “ … in the great feathers of the Wings and Tail distinguished with broad, transverse, blackish lines or bars; which lines are so formed, especially in the Tail, that each of the broader are terminated above and below by other narrower ones, like borders or fringes, disposed in a triple order, and at certain intervals distant from each other, as in Hawks.”

Next in the Cambridge Animal Alphabet: P is for critters that are part of one of the most significant of all human-animal relationships.

Have you missed the series so far? Catch up on Medium here.

Inset images: Barn owl in flight (Chris Thompson); Barn Owl (Pat Gaines); Owls from Ornithologia libri tres by Francis Willughby (Wren Library, Trinity College).

The Cambridge Animal Alphabet series celebrates Cambridge's connections with animals through literature, art, science and society. Here, O is for Owl, the researchers using their wing structure to inspire aeroacoustic developments, and the lavish drawings of them found in one of the world's first ornithologies.

We’ve been able to use advanced mathematics to understand an amazing natural phenomenon, which then inspired us to develop a practical engineering solution

Nigel Peake

Wren Library, Trinity College

Small Owl from Ornithologia libri tres by Francis Willughby

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

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