Toxostoma Rufum Research Articles

Tick infestation of birds across a gradient of urbanization intensity in the United States Great Plains

Migratory birds play an important role in large-scale movements of ticks and tick-borne pathogens, yet little is known about tick infestation of resident birds (e.g., non-migratory species and migratory species during the breeding season), especially in urban ecosystems. We captured birds during the breeding season in parks and greenspaces in Oklahoma City, Oklahoma, USA, to evaluate overall tick infestation patterns and to determine if urbanization influences infestation prevalence (the proportion of birds parasitized) and intensity (the number of ticks on infested birds). Of 459 birds, 111 (24.2%) had ≥ 1 tick, a high proportion of infestation compared with past North American studies. The most frequently infested species were Carolina Wren (Thryothorus ludovicianus; 56%), Brown Thrasher (Toxostoma rufum; 37%), and Northern Cardinal (Cardinalis cardinalis; 27%). The Lone Star Tick (Amblyomma americanum) comprised half (51%; n = 322) of all ticks on birds; other species sampled included Gulf Coast Tick (A. maculatum) (36%) and Rabbit Tick (Haemaphysalis leporispalustris) (13%). Urbanization intensity (i.e., the percentage of developed land around sites) was inversely related to infestation prevalence for all birds combined and for Carolina Wren, but intensity of infestation was unrelated to urbanization. Our results suggest that non-migratory and migratory birds during sedentary periods are important carriers of ticks in urban areas, and that tick infestation patterns can be influenced by the level of urbanization in the surrounding landscape. Clarifying how urban birds influence tick populations, and how urbanization shapes bird-tick interactions, will increase understanding of tick-borne disease ecology in urban ecosystems.

Passerine birds as hosts for Ixodes ticks infected with Borrelia burgdorferi sensu stricto in southeastern Virginia

The ecology of vector-borne diseases in a region can be attributed to vector-host interactions. In the United States, tick-borne pathogens are the cause of the highest number of reported vector-borne diseases. In the mid-Atlantic region of the eastern United States, tick-borne diseases such as Lyme disease, have increased in incidence, with tick-host-pathogen interactions considered a contributing factor to this increase. Ticks become infected with pathogens after taking a blood meal from a systemically infected host or through a localized infection while co-feeding on a host with other infected ticks. The host not only plays a role in pathogen acquisition by the tick, but can also facilitate dispersal of the tick locally within a region or over greater distances into new geographical ranges outside of their historical distributional range. In this study conducted in southeastern Virginia (USA), we examined the interaction between both resident and migratory bird species and Ixodes ticks, the primary vectors of Borrelia burgdorferi sensu stricto (s.s.) the main causative agent of Lyme disease on the East coast of the United States. Over a two-year period (2012–2014), 1879 passerine birds were surveyed, with 255 Ixodes ticks tested for the presence of Borrelia spp. Eighty passerine birds (4.3 %) representing 17 bird species were parasitized by at least one Ixodes tick, but only three bird species were parasitized by Ixodes ticks that tested positive for B. burgdorferi s.s. Twenty Ixodes ticks (7.8 %) tested positive for B. burgdorferi s.s. with nearly all collected from resident bird species including the Carolina wren (Thryothorus ludovicianus) and brown thrasher (Toxostoma rufum). Given that millions of birds pass through southeastern Virginia during migration, even with the low number of Ixodes ticks parasitizing passerine birds and the low prevalence of B. burgdorferi s.s. found within Ixodes ticks collected, the sheer volume of passerine birds suggests they may play a role in the maintenance and dispersal of B. burgdorferi s.s. in southeastern Virginia.

Exploring environmental coverages of species: a new variable contribution estimation methodology for rulesets from the genetic algorithm for rule-set prediction.

Variable contribution estimation for, and determination of variable importance within, ecological niche models (ENMs) remain an important area of research with continuing challenges. Most ENM algorithms provide normally exhaustive searches through variable space; however, selecting variables to include in models is a first challenge. The estimation of the explanatory power of variables and the selection of the most appropriate variable set within models can be a second challenge. Although some ENMs incorporate the variable selection rubric inside the algorithms, there is no integrated rubric to evaluate the variable importance in the Genetic Algorithm for Ruleset Production (GARP). Here, we designed a novel variable selection methodology based on the rulesets generated from a GARP experiment. The importance of the variables in a GARP experiment can be estimated based on the consideration of the prevalence of each environmental variable in the dominant presence rules of the best subset of models and its coverage. We tested the performance of this variable selection method based on simulated species with both weak and strong responses to simulated environmental covariates. The variable selection method generally performed well during the simulations with over 2/3 of the trials correctly identifying most covariates. We then predict the distribution of Toxostoma rufum (a bird with a cosmopolitan distribution) in the continental United States (US) and apply our variable selection procedure as a real-world example. We found that the distribution of T. rufum could be accurately modeled with 13 or 10 of 21 variables, using an UI cutoff of 0.5 or 0.25, respectively, arriving at parsimonious environmental coverages with good model accuracy. We also provide tools to simulate species distributions for testing ENM approaches using R.

Prevalence and consequences of ants and other arthropods in active nests of Midwestern birds

Many organisms build nests which create unique microhabitats that are exploited by other animals. In turn, these nest colonizers may positively or negatively influence nest owners. Bird nests are known to harbor communities that include both harmful and possibly beneficial species. We quantified the nest arthropod communities of 10 bird species in Illinois, USA, along a land-use gradient, focusing on ant prevalence. We found eight ant species in nests, and for three species, at least part of their colonies inhabited nests. The odorous house ant (Tapinoma sessile (Say, 1836)) was the most common species and maintained the largest colonies in nest material. Forest-cover percentage surrounding bird nests best predicted ant-colony presence. There was little evidence that ant presence influenced abundance or prevalence of other arthropods within nests with the exception of Brown Thrasher (Toxostoma rufum (Linnaeus, 1758)) nests, where a negative association between T. sessile presence and abundance of fly larvae was found. Breeding success did not differ between nests with and without ant colonies for any bird species. Ant species that exhibit polydomy and nomadism may be more likely to occupy ephemeral resources like bird nests than other ants. How widespread this phenomenon is and the degree of commensalism that both parties experience is unclear and warrants further investigation.

The behaviour of Cotinis nitida Linnaeus, the green June beetle (Coleoptera: Scarabaeidae), on mowed lawns makes them especially vulnerable to bird predators

ABSTRACTMales of the green June beetle Cotinis nitida are regularly attacked by birds as they search for females on lawns but which bird species feeds on the beetle changes from year to year. In 2018 for the first time on a farm in northern Virginia, brown thrashers (Toxostomum rufum) joined blue jays (Cyanocitta cristata) as major predators of the beetles. The two species employed very different tactics when hunting for June beetles, with the thrashers searching while walking forward on the mowed lawn while the jays scanned for beetles when perched in trees about the lawn. The beetles became very scarce at the lawn in early July in 2017 and 2018 and their predators apparently moved elsewhere. Subsequently, male beetles were occasionally observed patrolling a nearby hayfield in search of mates with rare copulations recorded after July 15. Because predatory birds could not exploit the beetles in the tall grass of the hayfield it seems likely that the mowed lawn constituted an evolutionarily novel ecological trap which made searching beetles conspicuous and easily captured by beetle-hunting birds.

Nest-Defense Behavior in Response to the Chatter Call in Tachycineta bicolor (Tree Swallow)

Birds produce a variety of vocalizations ranging in function from attracting a mate to alerting others of danger. One vocalization of Tachycineta bicolor (Tree Swallow), the chatter call, is reported to serve as both a mate-attraction call and a nest-defense call. We used playback techniques to investigate the nest-defense behavior of Tree Swallows to calls of Toxostoma rufum (Brown Thrasher; control) and Sialia sialis (Eastern Bluebird; nest competitor), and Tree Swallow shriek (alarm call) and chatter calls. We measured time spent foraging, remaining in the nest box, and on nest defense. Tree Swallows spent 80% of their time on nest defense in response to the chatter call. The chatter-call and shriek-call nest-defense responses were nearly identical. Our data show that the chatter call functions as an alarm call and elicits nest-defense behavior.

Avian Nest Success along a Habitat Gradient in the Cross Timbers Oak Savanna

Abstract Oak savanna, once widespread across central North America, has functionally vanished from most of its range due to land conversion or fire suppression and subsequent afforestation. Savanna-associated bird species have exhibited population declines as a result. One of the few areas containing remnant oak savanna is the vast Cross Timbers ecoregion of the south-central Unites States. Previous research in the Midwest showed some bird species exhibited higher rates of nest success (i.e., lower predation of eggs and nestlings) in restored savannas than in closed-canopy forests. Our objective was to quantify patterns of avian nest success across a gradient from open-canopy oak savanna to closed-canopy forest in the Cross Timbers ecoregion of southeastern Kansas. Daily nest survival rates for four common bird species—mourning dove (Zenaida macroura), yellow-billed cuckoo (Coccyzus americanus), brown thrasher (Toxostoma rufum), and northern mockingbird (Mimus polyglottos)—were modeled against covariates ...

Do Birds Alter Levels of Parental Investment Based on Nest‐Site Habitat Features?

AbstractMany habitats have undergone rapid changes over the past century as a result of anthropogenic activities. Organisms can respond to changes in their environment in many ways, including how much they invest in a given reproductive bout. Optimality theory and life history theory together have provided a framework for understanding how individuals make decisions about the risks and rewards of investing high levels of resources into their offspring within the context of current vs. future reproduction. Shrubland birds in the United States often breed in habitat that has been impacted by humans to varying degrees and provide an ideal system for examining whether organisms alter their levels of parental investment based on the habitat around the nest site. In this study, we assessed levels of nest‐defense behavior during a simulated nest predation event in four shrubland birds: American robins (Turdus migratorius), gray catbirds (Dumetella carolinensis), brown thrashers (Toxostoma rufum), and northern cardinals (Cardinalis cardinalis). We found that thrashers and catbirds exhibited significantly higher levels of nest defense compared to robins and cardinals and that birds with larger broods acted more aggressively in defending them. We also found that thrashers acted less aggressively as the proportion of shrubland around the nest increased and as the proportion of developed land around the nest decreased and that cardinals acted less aggressively as the proportion of developed land around the nest increased. These patterns suggest that nest‐defense behavior can covary with features of the landscape surrounding the nest, but that the factors shaping that behavior can differ by species.

Observation of a Brown Thrasher Nest (Toxostoma Rufum) on Stationary Farm Equipment

Observation of a Brown Thrasher Nest (Toxostoma Rufum) on Stationary Farm Equipment

New Records of Ixodes affinis (Acari: Ixodidae) Parasitizing Avian Hosts in Southeastern Virginia.

Ixodes affinis Neumann (Acari: Ixodidae) is a hard-bodied tick species distributed throughout much of the southeastern United States. Although I. affinis does not parasitize humans, it is a competent vector of Borrelia burgdorferi sensu stricto, the causative-agent of Lyme disease, and thus contributes to the enzootic maintenance of this pathogen. This study presents evidence of I. affinis parasitizing five new host passerine species. During 2012-2014, 1,888 birds were captured and examined for ticks, and 18 immature I. affinis were collected from 12 birds-six Carolina Wrens (Thyrothorus ludovicianus); two Brown Thrashers (Toxostoma rufum); and one American Robin (Turdus migratorius), Eastern Towhee (Pipilo erythrophthalmus), Northern Cardinal (Cardinalis cardinalis), and White-throated Sparrow (Zonotrichia albicollis). Of 15 larvae and 3 nymphs collected, one nymph tested positive for B. burgdorferi DNA. I. affinis was found co-feeding on birds with immature Amblyomma americanum (L.), Ixodes brunneus Koch, Ixodes dentatus Marx, Ixodes scapularis Say, and Haemaphysalis leporispalustris Packard. The results of this research provide a better understanding of I. affinis hosts and identify avian taxa that may play a role in the maintenance and dispersal of this tick species.

Mechanisms of egg recognition in brown-headed cowbird hosts: the role of ultraviolet reflectance

One of the most effective adaptations to counter avian brood parasitism is rejection of the parasitic egg, yet relatively few hosts reject eggs of the brown-headed cowbird, Molothrus ater. Studies have demonstrated that ultraviolet (UV; 300–400 nm) reflectance of eggs plays a role in egg rejection by hosts of parasitic cuckoos Cuculus spp. Only two studies have experimentally tested whether a cowbird host utilizes UV light when making egg rejection decisions, and those studies found no evidence that UV light was a significant factor. We experimentally blocked the UV reflectance of one host egg in the clutches of three rejecter species: brown thrasher, Toxostoma rufum, American robin, Turdus migratorius, and grey catbird, Dumetella carolinensis, to determine whether they utilize UV reflectance when rejecting eggs. We also measured the UV reflectance of each species' eggs. All host species rejected more of their own UV-blocked eggs than they did control eggs, but brown thrashers were significantly more likely to reject their own UV-blocked eggs than were American robins and grey catbirds. Brown thrasher eggs also reflected significantly more UV light than both American robin and grey catbird eggs. Our results coupled with those from similar studies suggest that hosts with brighter UV-reflecting eggs should be more likely to reject UV-blocked eggs than hosts with duller UV-reflecting eggs. This is the first study to demonstrate that UV reflectance is a parameter used by hosts of the brown-headed cowbird when rejecting eggs and further increases our understanding of the mechanisms of egg recognition in brood-parasitic hosts.

Seasonal use of habitat by shrub-breeding birds in a southeastern national forest

Abstract Populations of shrub-breeding birds are declining in eastern North America, and loss of habitat has been implicated in these declines. Seasonal use of habitat by shrub-breeding birds in the southeastern US remains understudied despite the fact that it is well documented that species resident within a region can shift habitat use dramatically between seasons. To better understand year-round habitat occupancy by shrub-breeding birds, we conducted bird counts and vegetation surveys during summer and winter 2008–2009 within Tuskegee National Forest, Alabama. We used multi-season occupancy models to examine use of habitat and to contrast seasonal occupancy patterns of four species of resident shrub-breeding birds—Brown Thrashers (Toxostoma rufum), Eastern Towhees (Pipilo erythrophthalmus), Northern Cardinals (Cardinalis cardinalis) and Carolina Wrens (Thryothorus ludovicianus). Brown Thrashers and Eastern Towhees are partially migratory—meaning some populations have separate breeding and wintering are...

Annual Survival of Birds Captured in a Habitat Island Bordered by the Urban Matrix of Baton Rouge, LA

Urban habitat fragments may provide birds the resources necessary to sustain viable populations in close proximity to human settlement. Conversely, urban habitat fragments may also act as ecological traps, where birds are lured into habitats that negatively affect reproduction or survival. In this study, we compared annual survival estimates of six common resident bird species captured at Bluebonnet Swamp, a 41.7-ha forest fragment bordered by the urban matrix of Baton Rouge, LA, with values derived from the Institute for Bird Populations' MAPS program to determine if populations sampled in the habitat fragment demographically deviated from regional baseline estimates. We found that three species captured at Bluebonnet Swamp exhibited survival estimates consistent with regional averages, whereas Cardinalis cardinalis (Northern Cardinal), Toxostoma rufum (Brown Thrasher), and Poecile carolinensis (Carolina Chickadee) survival estimates were lower than baseline. Edge effects associated with a relatively small preserve coupled with disease and semiannual movements in and out of the study area may be influencing Cardinal and Thrasher survival. We recommend that other studies focus on measuring avian demographics within habitat fragments to identify and mitigate factors that limit population sustainability in human-modified landscapes, as relative density alone may not be an appropriate metric for understanding the value of habitat fragments to birds.

Dead Birds

I didn't know exactly when my feelings for birds changed. I had once gone for walks in the state park near my home expecting a gift, knowing that I would see a bird that would delight me. I awaited the spring migration of birds through the Piedmont of South Carolina, where I live like a prisoner anticipating release, marking the days and watching and waiting for signs of its coming. First, out of the cold, almost silent, barren winter woods, the lengthening days of January and February would bring the renewed song of the resident birds: cardinals, Carolina wrens, brown thrashers, and robins. Then the fresh, budding leaves of poplar and oaks of March, April, and early May would produce the hatching of caterpillars and other insects. That would entice north, migrating waves of vireos and wood thrush, varied species of subtly beautiful warblers, and bold and brightly colored grosbeaks and tanagers. Each morning, with increasing excitement, I would record these in my journal. But last spring was different. I seldom took the time to look for birds and wrote nothing. For reasons I didn't understand, much of my enthusiasm for birds and most of the rest of life had died.

Bird Nesting in Chickasaw Plum Related to Age of Plum in Oklahoma

Abstract We described passerine nesting in Chickasaw plum (Prunus angustifolia) as related to plum age in north-central Oklahoma during the 2007 and 2008 nesting seasons to better understand the role of plum in bird ecology. We measured properties of nests (height aboveground), nest-supporting stems (height, diameter, age) and nesting stands (age, area). We observed Bell's vireos (Vireo bellii), brown thrashers (Toxostoma rufum), field sparrows (Spizella pusilla), northern mockingbirds (Mimus polyglottos) and painted buntings (Passerina ciris) nesting in plum stands and inferred nesting by blue grosbeaks (P. caerulea), greater roadrunners (Geococcyx californianus), mourning doves (Zenaida macroura) and northern cardinals (Cardinalis cardinalis). Nest height was consistent among species at averages ranging from 0.7 m (se = 0.13, n = 5) for field sparrows to 1.1 m (se = 0.07, n = 30) for northern mockingbirds. Bell's vireos and field sparrows nested on younger stems (average age = 7 y) than the ot...

Modeling regional-scale habitat of forest birds when land management guidelines are needed but information is limited

Conservation planning at broad spatial scales facilitates coherence between local land management and objectives set at the state or provincial level. Habitat suitability models are commonly used to identify key areas for conservation planning. The challenge is that habitat suitability models are data hungry, which limits their applicability to species for which detailed information exists, but managers need to address the needs of all at-risk species. We propose a modeling approach useful for regional-scale conservation planning that accommodates limited species knowledge, and identifies what managers should aim for at the local scale. For twenty at-risk bird species, we built models to identify potential habitat using both literature information and empirical data. Species occupancy within potential habitat depends on the presence of intrinsic elements, which we identified for each species so that managers can enhance these elements as appropriate. For most species, the estimated amount of habitat needed to meet population targets was <10% of the mapped potential habitat, with notable exceptions for Northern Goshawk ( Accipiter gentilis; 100%), Brown Thrasher ( Toxostoma rufum; 63.7%), and Veery ( Catharus fuscescens; 17.9%). Model validation showed that interior forest species models performed best. Our modeling framework allowed us to build potential habitat models to various endpoints for different species, depending on the information available, and revealed a number of species for which basic natural history data are missing. Our potential habitat models provide regional perspective and guide local habitat management, and assist in identifying research priorities.

Host Feeding Patterns of &lt;I&gt;Culex&lt;/I&gt; Mosquitoes (Diptera: Culicidae) in East Baton Rouge Parish, Louisiana

Host feeding patterns were examined for four species of Culex mosquitoes collected from 18 sites in or adjacent to East Baton Rouge Parish, LA, from November 2002 to October 2004. Host DNA from 37 bloodfed Culex coronator Dyar and Knab, 67 bloodfed Cx. salinarius Coquillett, 112 bloodfed Cx. nigripalpus Theobald, and 684 bloodfed Cx. quinquefasciatus Say were identified. The percentages of bloodmeals containing mammalian DNA were 94.6% for Cx. coronator, 82.1% for Cx. salinarius, 66.1% for Cx. nigripalpus, and 40.1% for Cx. quinquefasciatus. Human DNA was detected in 7% of the bloodmeals from Cx. quinquefasciatus and 2.7% of the bloodmeals from Cx. nigripalpus. The northern cardinal was the most frequent avian host of Cx. quinquefasciatus and Cx. nigripalpus. In 2003 and 2004, there was no significant relationship from May through October between the proportion of Cx. quinquefasciatus feeding on mammalian hosts and the date of collection. Of the six avian species most frequently fed on by Cx. quinquefasciatus, the northern cardinal, northern mockingbird, common grackle, and brown thrasher were fed on more frequently than expected based on their abundance. House sparrows were fed on less frequently than expected based on their abundance. These data support the conclusions of previous studies that Cx. quinquefasciatus is the most important vector for both the enzootic amplification and transmission of West Nile virus to humans in southern Louisiana.

Species recognition in a vocal mimic: repetition pattern not the only cue used by Northern Mockingbirds in discriminating songs of conspecifics and Brown Thrashers

Abstract Vocal mimics that produce large repertoires of song types, such as in the Mimidae, have unique challenges discriminating songs of conspecifics from those of other mimids in areas where these species co-occur. We investigated cues used by Northern Mockingbirds (Mimus polyglottos) in discriminating their songs from songs of a sympatric mimid, the Brown Thrasher (Toxostoma rufum). We presented territorial mockingbirds with four playback treatments in which either mockingbird song types or thrasher song types had either a standardized mockingbird repetition pattern (5 repetitions) or a standardized thrasher pattern (2 repetitions). Four measures (time within 2 m of speaker, latency to approach, closest approach, and number of flights) were used to estimate a subject's response to each playback. Subjects responded significantly more strongly to mockingbird song types in a mockingbird repetition pattern than to thrasher song types in either repetition pattern. Responses to mockingbird song types in a t...

EFFECTS OF VEGETATION AND BACKGROUND NOISE ON THE DETECTION PROCESS IN AUDITORY AVIAN POINT-COUNT SURVEYS

We used a bird-song simulation system to experimentally assess the effects of habitat, vegetation structure, and background noise on detection probability in aural avian point counts. We simulated bird songs of seven species in two habitats (mixed pine–hardwood forest and deciduous forest) and two leaf conditions (leaves on and leaves off) with two levels of background noise (~40 dB and ~50 dB). Estimated detection probabilities varied greatly among species, and complex interactions among all the factors existed. Background noise and the presence of leaves on trees decreased detection probabilities, and estimated detection probabilities were higher in mixed pine–hardwood forest than in deciduous forest. At 100 m, average estimated detection probabilities ranged from 0 to 1 and were lowest for the Black-and-white Warbler (Mniotilta varia) and highest for the Brown Thrasher (Toxostoma rufum). Simulations of expected counts, based on the best logistic model, indicated that observers detect between 3% (for the worst observer, least detectable species, with leaves on the trees and added background noise in the deciduous forest) and 99% (for the best observer, most detectable species, with no leaves on the trees and no added background noise in the mixed forest) of the total count. The large variation in expected counts illustrates the importance of estimating detection probabilities directly. The large differences in detection probabilities among species suggest that tailoring monitoring protocols to specific species of interest may produce better estimates than a single protocol applied to a wide range of species.

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...