Bird Calls Research Articles

From nose flutes to noise makers.

Flutes in a wide variety of forms often tell important parts of the stories of their cultures. Four flutes dated from about 40 000 years ago give tantalizing hints of the role of arts and music in that prehistoric setting. Thousands of ceramic flutes have been found among Mayan ruins in forms that evoke the calls of birds as well as those that could be used for music. The nose flute was considered in some Polynesian societies to be the only instrument worthy of waking the king, because breath from the nose was not tainted by the lies that mankind speak from the mouth. Finger holes are arranged either to control the length of the air column, or in the ocarina type, their combined area affects the frequency of a Helmholtz resonator. However, the nose flutes from western Polynesia have an intermediate form and a more complex note pattern. Flutes are sounded by an air jet that may come from a fixed fipple or from the player’s mouth or nose. Variations as in the ney and the kawala allow the player much more control and a distinctive tone.

BIRD AGAINST THE HUMEANS

Debate between Humean contingentists and anti-Humean necessitarians in the philosophy of science is ongoing. One of the most important contemporary anti-Humeans is Alexander Bird. Bird calls the particular version of Humeanism he is opposed to ‘categoricalism’. In his paper (2005) and in Chapter 4 of his book (2007) Bird argues against categoricalism about properties and laws. His arguments against categoricalism about properties are intended to support the necessitarian position he calls dispositional monism. His arguments against categoricalism about laws are intended to refute the contingent regularity view of laws (even in its sophisticated Lewisean version) and the nomic necessitation view of Armstrong (which involves a contingent necessitation relation). The general position Bird defends is that properties are necessarily related to the dispositions they bestow on their bearers and laws are necessary truths. I consider two of Bird's arguments against categoricalism about properties, and one of his arguments against the regularity view of laws. Maybe other arguments against categoricalism are persuasive. These, I submit, are not.

Wavewash

The bridge over Dickey Creek has been closed to cars, unsafe, so it's a one-mile hike to Rialto Beach over a paved, road-turned footpath. I like the serene incongruity of traipsing the yellow center line of an autoless strip of pavement, my breathing—the only engine sound, listening to liquid bird calls, and the still-distant surf-boom of the sea. The asphalt is crumbling at the edges, and here on my left, a slide has taken a third of its width into the Quilayute River, where a great blue heron stands in black water. To my right a jungly forest, mixed broadleafs and conifers with a lush undergrowth, presses in on the pavement. To my eyes, accustomed to the semi-arid landscape of eastern Oregon, it seems too verdant. The rainforest and river are reclaiming the road, though, which I can only count as progress. As I tramp in with the forty-odd pounds in my backpack, three ravens lift noiselessly out of the picnic area parking lot. The automobile pull-ups, of tidy concrete, wait for business. I hike past moss-filmed picnic tables, up the high-water gravel hump at the rear of the beach, and stand squinting at mild breakers and a vast litter of bleached-silver drift logs. Sunglasses. Damn it. But I won't go back to the truck. It's taken me too long to get going today, what with a trip from the night's campground back to the town of Forks to buy drugstore medicine for the cold I feel coming on.

Universal Features in the Singing of Birds Uncovered by Comparative Research

Aside from some exceptions, songbird species differ in the structure of their singing and usually also in the size and performance mode their song repertoires. In the past, most studies concentrated on the species specific differences of singing, and thereby contributed to a better understanding of their diversity. In our approach, however, we focussed on the opposite perspective; i.e. we investigated whether and how far songbirds share structural song properties. To have a solid data base we focussed on four species of thrushes which were famous for their large vocal repertoires. The two Asian bird species were Oriental Magpie Robins (Copsychus saularis) and Shama Thrushes (Copsychus malabaricus), the two European species the Common Nightingale (Luscinia megarhynchos) and the Thrush Nightingale (Luscinia luscinia). The latter were incorporated into a sample 40 other European songbird species (Table 1) serving as a framework for our comparative approach (Figure 2, 4). Besides well-known differences among species, our analyses of song material yielded some remarkably similar relationships between structural and functional song properties, which often were shared even by unrelated species. In particular measures of song durations were usually related to song application during vocal interaction. And, individual variation of song duration was mainly a result of differences in syllable repetition within trilled song sections. Although some of these findings were predicted already by former studies (see Todt, 2004), their essentials can be based now on profound data sets of detailed measurement.Keywords: European Thrushes, Asian Thrushes, Copsychus saularis, C. malabaricus, song structure, signal lengths.doi: 10.3126/on.v6i1.1648Our Nature (2008)6:1-14

Antipredator responses of wolf spiders (Araneae: Lycosidae) to sensory cues representing an avian predator

Predator detection and subsequent antipredator response behaviours have been documented in many vertebrate and invertebrate animals, although the degree of specificity in predator recognition and response varies. We examined responses of actively courting adult male Schizocosa ocreata (Hentz) wolf spiders to cues indicating the presence of an avian predator, including visual, seismic (substrate vibration) and acoustic (airborne) stimuli. Spiders responded to acoustic (bird call) and seismic (simulated beak tap) stimuli with cessation of courtship and movement, but increased locomotion when presented with a visual stimulus (bird shadow). Spiders responded to experimental playback of avian acoustic stimuli with antipredator behaviour significantly more often and took longer to return to courtship than when exposed to nonthreatening stimuli. Tests of responses on different substrata to isolate sensory modes revealed that spiders perceive airborne sound from bird calls as substratum-conducted vibration. Results indicate that S. ocreata are capable of recognizing sensory cues associated with avian predators and distinguishing them from nonthreatening stimuli, suggesting that bird predation has been a selection factor in shaping behaviour of this wolf spider species.

Native Writer Profile: Ralph Salisbury

Native Writer Profile:Ralph Salisbury Arnold Krupat (bio) The following brief essay will appear in slightly different form as the introduction to Ralph Salisbury's forthcoming book, Light from a Bullet Hole: New and Selected Poems, 1950–2008. Salisbury, a Cherokee from Iowa, born in 1926, has contributed to many journals and anthologies. Formerly editor-in-chief of Northwest Review, and the recipient of many awards, he is the author of nine books of poetry and two books of short fiction. He is currently professor emeritus at the University of Oregon and lives in Eugene, Oregon, with his wife, the poet Ingrid Wendt. Now in his eighty-third year to heaven, Ralph Salisbury has gifted us with a volume of new and selected poems in which there is no diminution of powers but an amazing further blossoming.1 The selected poems range from his earliest volume, Ghost Grapefruit and Other Poems (1972), through the chapbooks Pointing at the Rainbow: Poems from a Cherokee Heritage (1980) and Spirit Beast Chant (1982), on to Going to the Water: Poems of a Cherokee Heritage (1983), A White Rainbow (1985), Rainbows of Stone (2000), War in the Genes (2006), and Blind Pumper at the Well: Poems from My 80th Year (2008). Light from a Bullet Hole reprises "Some of the Life and Times of Wise-wolf Salt-town," as Salisbury etymologized his name in an autobiographical prose piece published in 1994 in Returning the Gift, and it brings us up to date.2 In "Scarlet Tornadoes," from Ghost Grapefruit, we discover that it was left to his father's "brother to tell me / that we were Cherokee," while in "A Black Half Moon," from Spirit Beast Chant, the child growing up tries out the names: "The [End Page 69] Cherokee—Tsaragi—Cave Men—Groundhogs / 'Yunwiya' their real name—'The People'—his own."3 From A White Rainbow come the poems "A Cherokee History Chapter Written Near the Globe Theater Site" and "Cherokee Initiation Rite: 1981," which may be compared to "Breed Kid's Initiation Rite: 1981," from Rainbows. "Three Visitations or Evocations," from the recent Blind Pumper at the Well, is dedicated to Joe "Dog" Smith, and it begins, "Old friend and fellow Cherokee."4 Also from Rainbows comes the lovely and moving "Being Indian," which opens, "Who we were seemed simple when gun / dropped meat onto plates." Its last stanza details change: The path to Granny's apples and talesTurkey Creek's bramble-tangled bank;the road snow, mud or dust, from my parents' farm,to redskin-plundering Carnegie's free—now tax-supported—library—war,for national survival through colonial tyranny,was my Medicine Way into the 20th Century,being what I was not ever simple again. The title poem of Rainbows, "A Rainbow of Stone," chronicles my Cherokee people's buffalo, deer,plantations, even our holy town,Echota, generations gone. To crime, monoxide, disease,and other city uncertainties.5 But in a vision that persists through Salisbury's work early to late, the poem concludes by imagining a time when even the arrogant sky-scraperswill bend,and, balled into foetal curl, the whole earth will be toe-to-toerainbows, my own and Thunder's and your homeagain. [End Page 70] In another poem from Blind Pumper, the poet appears at fourteen, in "War on, One Brother Sixteen, and I, Fourteen, Try to be Men." At fifteen, as "Direction of Storm," from Going to the Water, tells us, the young poet was struck by lightning on his family's Iowa farm: it "bleached my world / white like hospital sheets." In "Green Gophers," one of the new poems, the older poet sings back this young man who dreamedof targets too big for my air rifle to killand was naughty, though never successfully,in stopping the singing of birds,and joined, as soon as I could,the really naughty army.6 The teenage World War II Army airman appears in many of the poems.7 Thus, earlier, in "Green Smoke," the poet had remembered how, at . . . eighteen, I saved eight men,Nine if I count myself,. . . . . . . . . . . . . . . . .and now I'm a poetAnd try to save everythingI...

Divergence in Avian Communities Following Woody Plant Invasions in a Pine Barrens Ecosystem

We compared avian communities and vegetation characteristics in invaded and uninvaded pine barren ecosystems to test whether invasive woody plants were altering native bird communities. We hypothesized that structural changes in vegetation caused by the invasion of fire-intolerant deciduous trees were altering bird communities in the Albany Pine Bush, east central New York State. We recorded bird calls at 55 stations during breeding season to estimate abundances of breeding birds in areas dominated by fire-dependent pine-shrub savanna and areas dominated by invasive hardwoods (black locust, Robinia pseudoacacia, and aspens, Populus tremuloides and P. grandidentata). Vegetation surveys were conducted surrounding each station to quantify woody plant composition and structure. Sites characterized as invaded had more vegetation layers, twice as much closed canopy, and higher tree stem densities in all but the largest (> 25 cm dia) size classes. Forty-seven bird species were recorded; thirty-three at both invaded and uninvaded sites. Grassland/shrubland birds, such as prairie warbler (Dendroica discolor), field sparrow (Spizella pusilla), red-breasted nuthatch (Sitta canadensis), and eastern towhee (Pipilo erythrophthalmus), were twice as frequent and three times as abundant at uninvaded sites. Native bird species characteristic of closed-canopy forest were more frequent and abundant at stations in invaded sites. Multivariate analyses indicate distinct associations of particular birds with unique combinations of vegetation characteristics that differed between invaded and uninvaded points. A campaign of adaptive fire management holds promise to restore critical avian habitat in protected areas of this threatened barrens ecosystem.

A novel field evaluation of the effectiveness of distance and independent observer sampling to estimate aural avian detection probabilities

Summary 1. The validation of field sampling techniques is a concern for applied ecologists due to the strong model assumptions implicit in all methods. Computer simulations make replication easy, but they do not give insights into how much bias occurs in real populations. Testing sampling methods on populations of known size can establish directly how well estimators perform, but such populations are very hard to find, and replicate, and they may have unusual attributes. 2. We present a field validation of distance and double-observer methods of estimating detection probabilities on aural avian point counts. Our research is relevant to conservation agencies worldwide who design thousands of avian monitoring programmes based primarily on auditory point counts. The programmes are a critical component in the management of many avian species. 3. Our validation used a simulation system which mimics birds calling in a field environment. The system allowed us to vary singing rate, species, distance, the complexity of points, and other factors. 4. Distance methods performed poorly, primarily due to large localization errors, and estimates did not improve for simplified points. 5. For the double-observer method, two pairs of observers tended to underestimate true population size, while the third pair tended to double-count birds which overestimated the population. Detection probabilities were always higher and population estimates lower when observers subjectively matched birds compared to an objective rule and showed a slight negative bias and good precision. A simplified 45-degree matching rule did not improve the performance of double-observer estimates which had a slight positive bias and much lower precision. Double-observer estimates did improve on the simplified points. 6. Synthesis and applications . We encourage ecologists working with sampling methods to develop similar methods of working with simulated populations through use of technology. Our simulated field evaluation has demonstrated the difficulty of accurately estimating population size when limited to aural detections. Problems are related to limitations in the ability of observers to localize sound, estimate distance, and accurately identify birds during a count. Other sources of error identified are the effects of observers, singing rate, singing orientation and background noise.

Automatic detection of short time periodic bird calls in realistic monitoring scenarios

In this contribution, we propose a method for the automatic detection and localisation of bird calls featuring simple as well as highly repetitive structures. Reporting from a research project focused at computer aided acoustical monitoring, a detector for Locustella luscinoides (Savi's Warbler) is presented, performing reliably even on highly distorted recordings. In cooperation with the Animal Sound Archive at the Humboldt University, Berlin, this detector was incorporated into a multimodal censusing method combining GPS-data and automatically annotated audio recordings to perform line mapping. An evaluation of the proposed techniques for unsupervised monitoring purposes was also performed on 20 hours of multichannel recordings from Lake Parstein, a cane brake area in Germany. Finally, exemplifying the discriminative potential of the underlying features, we will point out the application to other members of the Warbler family as well as the detection of cricket and toad sounds.

Experience with VoxNet: a rapidly‐deployable acoustic monitoring system for bio‐acoustic studies

Terrestrial bioacoustic census is a difficult problem because of propagation characteristics, obstructions, the diversity of bioacoustic sources, and the impact of noise. To address this problem we have developed VoxNet, a complete hardware and software platform for distributed acoustic monitoring applications. Each VoxNet node is a portable, self‐contained processor with a small four‐channel acoustic array. Using a distributed set of VoxNet nodes, a forested habitat can be monitored and the behavior of animals can be recorded and analyzed acoustically. In this work we present our experiences applying VoxNet to bioacoustic census. This work is based on data collected using the system during a deployment in Chiapas, Mexico at the Chajul Biological Field Station. The Chajul station is located in a region of dense rain forest and is home to Mexico's most diverse ecosystem. Using VoxNet in this harsh environment, we obtained census estimates based on observation of bird calls.

The Politics of Love in Mandla Myeko's <i>Apho Sikhala Khona Isakhwatsha</i>

During the apartheid era, the media in South Africa were prevented from exercising freedom of speech and this forced its practitioners either to find covert ways of expressing themselves or, in some cases at least, simply to toe the line. Such was the case at the Xhosa language radio station, where radio dramas, for example, could not openly be critical of the regime. This paper examines Mandla Myeko's 1981 play, Apho Sikhala Khona Isakhwatsha (Where the Go-Away Bird Calls), and argues that, despite harsh media legislation (most notably Publications Act Number 42 of 1974) during the period in question, some radio practitioners, such as Myeko, engaged with the apartheid regime, although they had to camouflage messages that could be deemed subversive. In spite of the state's heavy-handed censorship of radio texts, then, some of these anti-apartheid messages reached audiences. In this regard, I concur with Liz Gunner's contention that “[t]he censorship of overtly political themes has not meant that what was being produced did not engage with the harsh consequences of apartheid, or with the desire of listeners both to find a medium which would express their suffering and their search for a better life” (2002, 231). English in Africa Vol. 34 (2) 2007: pp. 67-79

The Best Cake Made Both of Us Sad

The Best Cake Made Both of Us Sad Chris Offutt (bio) Last night’s rain has drained the air of all but blue. I am outside listening to the singing of birds. The Daniel Boone National Forest begins at the tip of my fingertips, while civilization spreads the opposite way. My sons are in the house playing a board game, one I played with my brother as a child, but one of the boys gets mad and the laughter stops. As the sun rises high the heat douses the singing of the birds. I am left soundless—feeling as if I should enter the house and settle the kids or enter the woods and revive the birds. Instead I remain marooned in the shade. Today is that rare day when I’m content to sit in the sun and straddle the boundaries of my life. Earlier this morning I watched my children sleep. Their bodies lay in such abandon, sprawled across the sheet, a testament to the safety they feel at home. I kiss their cheeks knowing that they will never remember it but hoping that the ghost of my kiss will carry throughout their days. The children cheer me up and give me light. Sometimes I lie beside their warmth and worry about my future life after they leave home. Where will I find moments of joy? Who will make me smile and hug me tight? How will I live in a house with no laughter? Perhaps it will be like the woods in winter—occasional visits from the birds who sing briefly and alone. Last night I talked to Arthur on the phone. He tells me he is lonely. His friends are dead; he’s outlived them all. He is back-up man at his temple in order to make a quorum for a minyan, and he sees some people then. They are all retired. They look at their lives and examine what they’ve done with them. One man says, I’ve made a million dollars. Another says, I’ve made two. Someone else has a yacht and a place in Florida. Arthur claims none of these. He says that he is shrinking. The cabinet doors of his kitchen no longer bang the top of his head. [End Page 231] He spent years walking into the doors from his blind side, then getting angry at his wife for leaving them open. At last, he says, old age has made him safe from himself in the kitchen. His body is drawing up, shriveling in advance of death. As he becomes smaller, so does his world, the places he goes—a deli, his backyard, a bakery. Yesterday at the bakery a woman cut line in front of him, but he let it go. Another woman did the same thing, and he said that he was there first, and the worker apologized. She hadn’t seen him standing there. Good thing Arthur says to me, that she didn’t say I was short. I laugh because this is a reference to his having once knocked a young man to the floor of a bank for calling him short. It occurred ten years ago, the day before a visit to Rita and me in Iowa. He was running late. He was nervous about the flight. He told the story with shame and humility but secret pride. At age seventy he could still take care of himself. Now, at eighty, he cannot. The last time he tried to kneel he was unable to rise. He cannot run and he cannot punch. His bowels treat him unfairly. Waw, he says, it’s no fun, this getting old. No fun at all. The key to understanding Arthur is knowing something of myself. I can never be truly happy because I mourn everything in advance—the wilting of flowers before they bloom, children leaving home, the end of each season while still at its apex. I enjoy the sunniest of days while bemoaning that there are not more of them. The same is true of food and sex. Every meal is the finest, which means there will never be another. The last time I made...

Sung Birds: Music, Poetry, and Nature in the Later Middle Ages (review)

Reviewed by: Sung Birds: Music, Poetry, and Nature in the Later Middle Ages Jason Stoessel Sung Birds: Music, Poetry, and Nature in the Later Middle Ages. By Elizabeth Eva Leach. Ithaca: Cornel University Press, 2007. [xiii, 345 p. ISBN-10 0801444908; ISBN-13 9780801444913. $55.] Illustrations, music examples, bibliographical references, index, appendices. In Sung Birds, Elizabeth Leach argues that rationality lay at the heart of many definitions of music in the Middle Ages and, on this basis, sounds like the calls of birds were excluded as musical utterances. But Leach goes further, demonstrating that there existed in medieval musical culture, [End Page 490] on one hand, an inherent tension between the conventional definition of music as a rational art and, on the other hand, the repeated use of references to the natural world as a means of articulating cultural subjectivity and locating musical creativity. Sung Birds consists of six chapters and five appendices that serve the preceding discussion. Chapter 1, "Rational song," argues that birdsong occupies an ontological status that exists outside conventional definitions of music articulated during the Middle Ages. Chapters 2 and 3, "Birdsong and Human singing" and "Birds Sung," examine the nature and use of birdsong and references to birdsong in medieval musical theory and song. Chapter 4, "Silent Birds," extends the discussion of the status of different non-musical sounds like birdsong by studying examples of texts and musical settings from the trecento that includes sounds of dogs barking, and voices of shepherdesses and falconers calling their charges. Chapter 5, "Feminine birds and Immoral Song," continues a thread of discussion established in the previous chapter by examining constructions of femininity in music and the moral status of such constructions. The final chapter, "Bird Debates Replayed," moves beyond the subject material of the Middle Ages to discuss the ontological position of music in modern and post-modern societies. Leach's text demonstrates a cross-disciplinary approach that develops contextual readings of musical culture and its artifacts through the examination of not only music and music theory but also close readings of contemporary literature, both theoretical and literary, that she injects with approaches from gender and sexuality studies. A significant merit of Leach's scholarship is fresh approaches to well-known texts. Rather than perpetuating the accepted reading of Eustaches Deschamps's L'art de dictier (1392), which concludes that the author of this treatise favors poetry over music, Leach demonstrates that Deschamps advocates the marriage of text and music as sung text (p. 59). The author achieves this reading by situating Deschamps's categories of natural and artificial music within the dialectic of John of Salisbury. Similarly a close reading of Arnulf of St. Ghislain's music theory in conjunction with Alan of Lille's De plantu naturae reveals in the former text what may be termed Bahktian textual polyphony. This serves to articulate different levels of meaning, the most learned level reliant on intertexts directed to Christian moral truths. Readers might find the book's sudden digressions into sexuality and psychosexual readings of texts odd at times. It is regrettable that there is no concerted attempt to construct a discussion of sexualities in medieval music in a more orderly fashion. Such a discussion might have begun with the concepts of sexuality such as those narrated far too late on page 267. Instead, we are left with rather general, often jarring interjections that leave the reader wondering what the writer actually means. What are the possible sexual connotations of Giovanni da Firenze's Per larghi prati (p. 202)? Does the piece stage lesbian delight or Bacchic frenzy? Similar questions abound concerning the appropriateness of psychosexual readings (p. 230) heavily indebted to Freud's Three Essays on Sexuality. One difficulty encountered by this reviewer is the author's statement that she wants "to explore the ontology of music in the middle ages" (p. 14). Leach sets out two premises in chapter 1 on the status of music in the Middle Ages as a rational art. The first of these is that the Neoplatonic concept of the three species of music—musica mundana, musica humana, and musica harmonica—resides in a human-based rationality of Pythagorean natural proportionality. The...

THE FUTURE OF ENVIRONMENTAL PHILOSOPHY

The Future of Environmental Philosophy Irene J. Klaver Environmental philosophy is invitational: it in-vites thinking into life as well as life into thinking. Life is vita in Latin—the same vita as in vital and in vitamins. An in-vita-tion leads to new connections, or a renewal of existing relations. This affects how we understand things. As Wittgenstein says, "understanding [...] consists in the very fact that we 'see connections.'"1 This is the case for philosophy in general, it makes connections, reveals relations between entities, thoughts, and events, which elucidates our understanding. Environmental philosophy has (re-)opened certain realms of relevance to philosophical inquiry by foregrounding our connections to the non-human world. It accommodates the broadest invitation: of life itself, including our relation to the conditions of life. The future of environmental philosophy lies precisely in this broad invitation. That means that it needs to occupy a profoundly interdisciplinary place, at the node of multiple institutions and practices. It deals with global issues on a local level and with the effects of local issues on a global scale. This involves science, policy, economy, law, ethics, aesthetics, religion, history, etc. An environmental philosopher is a specific generalist, someone who can connect various relations, sees the multiple angles in a particular perspective, the world in a grain of sand. The evolved environmental philosopher is a translator, translating various concerns along multiple perspectives. Translation is crucial to an understanding of the viewpoints, positions, and situations of others. Environmental philosophy enlarges the category of the "other" with many more entities. This is not a politically correct move to bring so-called repressed voices to the fore, it is to evoke different modes of knowledge and experience, to enhance cultural imagination2 , a crucial component to raising awareness about environmental concerns. In her 1962 book Silent Spring3 , Rachel Carson connected pesticide DDT to the decline in some predatory bird populations and sparked the rise of the environmental movement. She triggered a powerful cultural imagination by invoking a future silent spring without the singing of birds. Hegel saw the owl of Minerva as the symbol of wisdom, spreading "its wings only with the falling of the dusk."4 That is, for Hegel understanding arises after the events, philosophy can never be prescriptive. [End Page 128] Environmental philosophy, on the contrary, is engaged thinking, its understanding arises out of the practices of the everyday. The albatross around our neck is of our own shooting. Environmental ethics and environmental justice might stake out basic prescriptive rules, but these are always born from knowledge of—if not a participation in—certain practices. Environmental philosophy's bird is the spotted owl of social-political engagement, the canary in the mineshaft, but also the sparrow in the backyard. Birds that fly from dawn to dusk, seeing and reporting in the light the practical connections that reveal understanding, possible action, communication needs, and suggest a lexicon for translation. In and through practical connections rises therefore translation and understanding. Understanding is a transformative process—it changes our interpretative frameworks. When we see connections we begin to understand how the dead zone in the Gulf of Mexico is related to agriculture in the midwestern United States thousands of miles away, with watersheds within the Mississippi River Basin draining nitrogen fertilizers into the Mississippi, causing hypoxia in the Gulf.5 Environmental philosophy shows how wetlands are not just wastelands but take nitrogen and phosphorus out of the water, buffer "our" coasts, and feed the migrating birds along their long routes. By not seeing these connections, our wetlands are pumped dry; and by abusing our water, springs disappear, major rivers strand in sand, and dead zones emerge in oceans and seas. "These, too, were silent, deserted by all living things," Rachel Carson states, writing about streams.6 In the twenty first century it is no longer a "fable of tomorrow:" silent springs, silent rivers, silent seas. Environmental philosophy is empirical philosophy dealing with big issues such as global warming, biodiversity, and sustainability, but...

Classification of wolf call types using remote sensor technology

A system is presented for the near-real-time classification of calls from captive Alaskan (Canis lupus occidentalis) and Mexican (Canis lupus baileyi) wolves as well as other ambient sounds such as bird calls and anthropomorphic noise. Signals are detected on a Viper network node at The California Wolf Center using a signal-to-noise ratio based call activity detector. These calls are transmitted over a regional high-speed wireless network (HPWREN) to a remote processing facility located 50 miles from the collection site. Cepstral feature vectors are extracted from candidate calls at the remote facility and are classified using a hidden Markov model pattern recognition system trained with manually labeled data representing the wolf ethogram and other common noises in the soundscape. In an offline evaluation with known segmented data, the system achieves an 84% accuracy. [This work is supported by HPWREN, NSF Grant No. 0426879.]

Birdsong: A Natural History (review)

Reviewed by: Birdsong: A Natural History Michael Branch (bio) Birdsong: A Natural History By Don StapScribner, 2005261 pages, cloth, $24.00; paper, $15.95 As the literature of the past few thousand years makes plain, humans from various cultures have maintained a consistent fascination with—and admiration for—the songs of birds. And if poets have sometimes doubted their ability to adequately describe birdsong, it appears that scientists have not been much more successful. Despite having one of the most compelling subjects in the biological world, scientists who study "avian bioacoustics" continue to be troubled by a number of fascinating questions. Some of these questions involve complex evolutionary issues. For example, what is the role of song dialects within bird communities, and what effect does dialect range have on avian genetic fitness and speciation? But many of the questions that remain will strike readers as surprisingly basic. How do birds learn their songs? What is the window of opportunity for that learning? Why do certain individuals customize their expression of a shared song? Is bird singing strictly related to mating and territorial behavior, or is it possible that birds actually sing for the sheer pleasure of it? Why do birds sing? Don Stap's Birdsong: A Natural History reminds us from the outset that we do not yet know the answer to this fascinating question. Among the pleasures of Birdsong is Stap's effective use of what scientists already know about birdsong to help revivify our admiration for all that chirping and warbling that we hear around our homes. For example, a singing bird uses almost 100 percent of the air passing across its vocal cords to make sound; compare that to the 2 percent or so used by the bird's human neighbor who is singing in the backyard. Or, consider that the average brown thrasher knows more than 2,000 songs. How many of us could [End Page 180] say the same? And many bird species have, over millennia, shaped form to function by developing anatomical adaptations that allow for amazingly complex vocalizations. Many birds, for example, have evolved a syrinx with dual bronchial tubes that can be used to produce sounds of completely different frequencies—a neat trick that allows the bird to simultaneously project two sounds that are not harmonically related and thus, in effect, "[sing] a duet with itself." Though it is not his main subject, Stap is also interested in human conceptions of birdsong, and some of the book's most illuminating moments examine this cultural link between people and birds. "Frogs croak, crickets chirp, wolves howl, and lions roar," he writes, "but birds sing." Do birds communicate in a way that is fundamentally different from other animals, many of which also use vocalizations in complex ways? Or is it the case that the beauty of the warble is in the ear of the beholder? Does our use of the word "song" to describe avian vocalization reflect something fundamental to the sound itself, or do we call bird vocalizations "song" simply as a way of expressing a human aesthetic preference for the sound of the house finch over that of the bullfrog? In discussing this issue of what we might call "acoustic aesthetics," Stap tells fascinating stories of interactions between human and bird "music"—as in the case of Beethoven, Mozart, and Bartók, all of whom incorporated avian melodies into their compositions. (Next time you hear Beethoven's Sixth, listen for cuckoo, nightingale, and quail song!) Birdsong incorporates and describes biological science, but is not itself a scientific book. Instead, Don Stap's primary technique—one that has been used by many environmental writers and documentarians—is to follow scientists around in the field, describing their work and translating their hypotheses and findings into language that nonspecialist readers can understand and appreciate. To this end Stap has made a sort of literary character of his main figure, renowned avian bioacoustics specialist Don Kroodsma. Kroodsma tramps around the world, hauling piles of field equipment and recording gear, and showing infinite patience as he waits for the right moment to funnel a rare song into the cone of his parabolic microphone. While a great deal...

Development of family specific contact calls in the Long‐tailed Tit Aegithalos caudatus

Contact calls are ubiquitous among birds and are important in mediating social interactions. Despite this, the structure and function of these vocalizations have received relatively little attention, and the ontogeny of all bird calls is poorly known. In co‐operatively breeding Long‐tailed Tits Aegithalos caudatus, helpers preferentially provide care at the nests of close relatives and contact calls act as cues for kin recognition. However, it is not known whether these calls act as individual‐specific or family‐specific cues, or if they differ between the sexes. Furthermore, the precise nature and timing of the development of these calls is not known. Here we use spectrographic cross‐correlation to show that two different contact calls in the Long‐tailed Tit exhibit some degree of family‐specificity but no sex‐specificity, and the implications for kin recognition are discussed. We also provide evidence that both call types develop in the nest, and we give one of the first descriptions of nestling vocalizations from hatching through to fledging in a passerine species.

The biology and evolution of music: A comparative perspective

Studies of the biology of music (as of language) are highly interdisciplinary and demand the integration of diverse strands of evidence. In this paper, I present a comparative perspective on the biology and evolution of music, stressing the value of comparisons both with human language, and with those animal communication systems traditionally termed “song”. A comparison of the “design features” of music with those of language reveals substantial overlap, along with some important differences. Most of these differences appear to stem from semantic, rather than structural, factors, suggesting a shared formal core of music and language. I next review various animal communication systems that appear related to human music, either by analogy (bird and whale “song”) or potential homology (great ape bimanual drumming). A crucial comparative distinction is between learned, complex signals (like language, music and birdsong) and unlearned signals (like laughter, ape calls, or bird calls). While human vocalizations clearly build upon an acoustic and emotional foundation shared with other primates and mammals, vocal learning has evolved independently in our species since our divergence with chimpanzees. The convergent evolution of vocal learning in other species offers a powerful window into psychological and neural constraints influencing the evolution of complex signaling systems (including both song and speech), while ape drumming presents a fascinating potential homology with human instrumental music. I next discuss the archeological data relevant to music evolution, concluding on the basis of prehistoric bone flutes that instrumental music is at least 40,000 years old, and perhaps much older. I end with a brief review of adaptive functions proposed for music, concluding that no one selective force (e.g., sexual selection) is adequate to explaining all aspects of human music. I suggest that questions about the past function of music are unlikely to be answered definitively and are thus a poor choice as a research focus for biomusicology. In contrast, a comparative approach to music promises rich dividends for our future understanding of the biology and evolution of music.

Accessible Pedestrian Signals

The U.S. Access Board's Draft Guidelines for Accessible Public Rights-of-Way recommends the use of push-button-integrated accessible pedestrian signals (APSs). This research compared the effect of specific features of push-button-integrated APSs on the ability of blind pedestrians to locate and correctly use push buttons and to cross accurately during the pedestrian phase. A rapid-tick walk signal promoted the fastest onset of crossing compared with speech messages and bird calls and is therefore the preferred signal. However, speech walk indications are needed where two APSs are mounted on the same pole. Although variations in the standard features made little difference to users who were thoroughly familiar with devices, empirical evidence from participants with less knowledge of the devices as well as subjective data lead to the recommendation that APS devices include a push-button locator tone, a rounded push button with an activation tone or message, a tactile arrow incorporated into the push button, responsiveness to ambient sound, and a push-button information message and beaconing in response to an extended button press.

Accessible Pedestrian Signals: Effect of Device Features

The U.S. Access Board's Draft Guidelines for Accessible Public Rights-of-Way recommends the use of push-button-integrated accessible pedestrian signals (APSs). This research compared the effect of specific features of push-button-integrated APSs on the ability of blind pedestrians to locate and correctly use push buttons and to cross accurately during the pedestrian phase. A rapid-tick walk signal promoted the fastest onset of crossing compared with speech messages and bird calls and is therefore the preferred signal. However, speech walk indications are needed where two APSs are mounted on the same pole. Although variations in the standard features made little difference to users who were thoroughly familiar with devices, empirical evidence from participants with less knowledge of the devices as well as subjective data lead to the recommendation that APS devices include a push-button locator tone, a rounded push button with an activation tone or message, a tactile arrow incorporated into the push button, responsiveness to ambient sound, and a push-button information message and beaconing in response to an extended button press.