City Birds Research Articles

Do Bewick´s Wren (Thryomanes bewickii) nestlings experience thermal stress in nest-boxes in a tropical urban city?

Urban areas present thermal environments that may be challenging for altricial nestlings, particularly in early development. We aimed to evaluate whether altricial Bewick's Wren (Thryomanes bewickii) nestlings experienced thermal stress in the nest-box during the early- and late-developmental stages. We determined the thermoregulatory set point (thermoneutral range) of nestlings by measuring cloacal body temperature of five nestlings from three nests, every other day from hatching until they fledged. We also exposed nestlings to a thermal challenge from day 5 to determine the age of endothermy. We used dataloggers to determine the thermal environment inside and outside of three nest-boxes, and obtained the operative temperature for nestlings in the nest-box using 3D-printed models corresponding to early- and late-developmental stages. Ambient temperatures inside the nest box fluctuated throughout the day, being colder at night just before day-break (min range: 10.4°C – 10.8°C), and hotter in the afternoon (max range: 25.8°C - 28.3°C). However, temperatures in the nest-box did not reach the extreme high and low outside temperatures, and were warmer at night. Nestlings reached age of endothermy at 9 ± 2.3 days after hatching, and showed a thermoneutral range of body temperature above ambient temperatures in the nest-box. Operative temperatures of models in the nest-box closely followed ambient temperatures, and were below nestlings´ thermoneutral range. Therefore, nestlings could experience thermal stress when parents do not provide additional buffering while off the nest for foraging. Although nest-boxes provide limited thermal benefits for nesting birds in tropical cities, they still provide valuable nesting and roosting sites where natural cavities are limited in availability.

Opposite Responses of Native and Nonnative Birds to Socioeconomics in a Latin American City.

Due to the massive increase of the urban population, a global target is to achieve sustainable cities that are sensitive to nature and environmentally just for urban dwellers. To accomplish this, it is important to understand the responses of native and nonnative birds, identify the environmental variables that promote native species and limit nonnative species, and understand how they vary among socioeconomic groups. Although many cities in the Global South exhibit strong social and environmental segregation, few studies have investigated the relationship between socioeconomics and biodiversity. Therefore, to help promote ecological justice and biodiversity conservation in the developing world, we investigated the influence of socioeconomic level and woody cover on bird species richness and abundance in the city of Santiago de Chile. We also investigated whether bird response changes with species provenance-it is important to understand the response of native birds separately from nonnative birds because they imply opposite management strategies (e.g., conservation vs. species control/eradication). Thus, we surveyed 120 sites located in residential areas of high, medium, and low socioeconomic levels across the city and fit generalized linear (mixed) models that described bird species richness and abundance for total, native, and nonnative birds according to socioeconomic level and woody vegetation cover. We found that both socioeconomic level and woody vegetation cover influenced the bird community, but their effects changed with bird species origin, having opposite effects on native and nonnative birds. Residential areas where wealthier people live supported greater species richness and abundance of native birds than residential areas where people of lower socioeconomic status live. In contrast, residential areas where vulnerable people live had greater bird abundance that was mainly composed of nonnative birds. Therefore, affluent neighborhoods provide more opportunities to encounter native birds and experience nature close to home than poorer neighborhoods. Due to woody cover having positive effects on native birds and a negative influence on nonnative birds, increasing tree and shrub cover will contribute to supporting more native birds in residential areas deprived of woody vegetation, which are commonly low socioeconomic areas. Additional variables that can explain bird response among residential areas of different socioeconomic levels need to be investigated to better understand the factors influencing the distribution of birds in cities and promote a more biodiverse and environmentally just city.

Історія вивчення зимової орнітофауни міст України

Knowledge of wintering avifauna and the study of wintering aspects of birds make it possible to obtain information about the diversity and status of the populations of birds during one of the most unfavorable periods of their life. Significant changes in climatic conditions in winter period during the last decades in Europe are noticeable. They affect winter distribution and dynamics of a number of bird species. In particular, new species appear, what may be caused by changes in wintering places or migration routes, or birds that were previously migratory remain for the wintering. Therefore, systematic research of winter avifauna in the territory of urban agglomerations of different levels is a relevant and important task for today. In our opinion, the study of winter avifauna of urban agglomerations can be classified into several groups: year-round, global, partial and selective. The vast majority of winter avifauna studies were partial, conducted by scientists specializing in the study of individual species or groups of birds. Most often, ornithologists focused their attention on predators and birds of the wetland complex. Nowadays, according to the results of research conducted by ornithologists of Ukraine, we can distinguish three distinctive stages, which are not entirely clear, but reflect the development of research on winter avifauna and are indicative in the selection of research objects and territories. The first stage is the study of wintering birds of Ukraine of large water bodies or territories, such as areas with non-freezing ponds; the second – records and study of individual species or groups of birds, in particular wintering of shrikes, representatives of the Corvidae family, and the third – direct research of avifauna in urbocoenoses. The latter stage of research is the most recent. Now, ornithologists drew their attention to avifauna changes in urban agglomerations due to the increasing urbanization rates, which may cause a decrease in the species diversity and number of birds in cities in the nearest future, as a result of their displacement and the impossibility of staying in an anthropogenic environment.

The surface urban heat island effect decreases bird diversity in Chinese cities

The audiovisual experience of observing birds in cities provides numerous benefits to residents, but their diversity is endangered by urbanization. Although the magnitude of the surface urban heat island effect (hereafter SUHI) has grown in recent years, its impact on bird diversity has not been adequately investigated. Here, we calculate the SUHI in 336 Chinese cities and we document the implications of the SUHI for avian species richness and functional diversity during the 2001, 2011, and 2019 breeding and non-breeding seasons. We predict that the SUHI will result in greater species richness and functional diversity in urban areas during the non-breeding season, especially for cities located within colder regions of China where the SUHI is more likely to relax thermoregulatory costs and reduce the propensity of some species to migrate. We predict that the SUHI will result in decreased species richness and functional diversity during the breeding season due to increased physiological stress, especially for cities located within warmer regions of China. Our findings showed that the SUHI was associated with lower species richness and lower functional diversity of birds in urban areas compared to suburban areas during both the breeding and non-breeding seasons. These results suggest that the SUHI induced birds to avoid urban areas or to move to cooler suburban areas during both the breeding and non-breeding seasons. This effect persisted irrespective of a city's size or geographical location. Our findings suggest that the SUHI is degrading bird diversity in Chinese cities.

Ingrained city rhythms: flexible activity timing but more persistent circadian pace in urban birds.

Urbanization dramatically increases the amount of light at night, which may disrupt avian circadian organization. We measured activity patterns of great tits breeding in the city and forest, and subsequently measured two clock properties of these birds under controlled conditions: tau (endogenous circadian clock speed) and after-effects (history dependency of the clock relative to previous conditions). City and forest birds showed a high repeatability of activity onset (0.60 and 0.41, respectively), with no difference between habitats after controlling for date effects. Activity duration and offset showed more variance, without a difference between birds from the two habitats. Tau did not differ between city and forest birds, however, city birds showed stronger after-effects, taking more days to revert to their endogenous circadian period. Finally, onset of activity was correlated with clocks speed in both habitats. Our results suggest that potential differences in activity timing of city birds is not caused by different clock speeds, but by a direct response to light. Persistence in after-effects suggests a reduced sensitivity of the clock to light at night. Urbanization may select for clock properties that increase the inertia of the endogenous circadian system to improve accuracy of activity rhythms when exposed to noisier lighting cues.

Study of human knowledge and attitude toward urban birds in Faisalabad city, Pakistan.

Birds are very valuable indicators of species richness and endemic patterns in a specified ecosystem, which eventually help the scientist to measure the environmental degradation. The aim of present study was to know human knowledge and attitude toward urban birds in Faisalabad city, Pakistan. The study conducted in four consecutive months: November 2019 to February 2020. Population of birds was noted from eight residential towns of Faisalabad city, data were collected through questionnaire. Faisalabad has a reasonably large population of birds and present data show that, there is a significant difference between favorite bird of residential areas and institutions. The pigeon received the most likeness in bird population among residential area residents, while the myna received the least. The most popular bird in Faisalabad institutions was the sparrow, while the least popular bird was the common myna. Bird adaptation percentage of residential areas and institutional areas of Faisalabad was the highest for parrot and sparrow respectively. People in residential areas and institutions, on the other hand, adapted least to common myna. It is concluded that people of the study area like birds and offered food and high population of birds are present in study area.

Intestinal worms parasitic in some types of birds in Tikrit city and their effect on the intestine histological picture

Intestinal worms parasitic in some types of birds in Tikrit city and their effect on the intestine histological picture

City birds are changing their tune

City birds are changing their tune

Drivers of avian habitat use and detection of backyard birds in the Pacific Northwest during COVID-19 pandemic lockdowns

Birds living in developed areas contend with numerous stressors, including human disturbance and light, noise, and air pollution. COVID-19 pandemic lockdowns presented a unique opportunity to disentangle these effects during a period of reduced human activity. We launched a community science project in spring 2020 to explore drivers of site use by and detection of common birds in cities under lockdown in the U.S. Pacific Northwest. Our goals were twofold: (1) consider how intensity of urbanization, canopy cover, and availability of bird feeders and bird baths influenced avian habitat use; and (2) quantify how daily changes in weather, air pollution, and human mobility influenced detection of birds. We analyzed 6,640 surveys from 367 volunteers at 429 monitoring sites using occupancy models for 46 study species. Neither land cover nor canopy cover influenced site use by 50% of study species, suggesting that backyard birds may have used a wider range of habitats during lockdowns. Human mobility affected detection of 76% of study species, suggesting that birds exhibited species-specific behavioral responses to day-to-day changes in human activity beginning shortly after initial lockdown restrictions were implemented. Our study also showcases how existing community science platforms can be leveraged to support local monitoring efforts.

Unexpected dispersal of Australian brush‐turkeys (Alectura lathami) in an urban landscape

AbstractAustralian brush‐turkeys (Alectura lathami) are atypical urban colonising birds due to their poor flight and dispersal ability, ground foraging and nesting behaviour, and lack of parental care for their chicks. Despite this, they have become increasingly common in urban areas in Australia, including major cities such as Sydney and Brisbane. The drivers of the brush‐turkey spread into urban areas, and the mechanisms behind their dispersal remain poorly understood due to the difficulty of tracking individual birds over multi‐year timescales. Here, we report on the long‐distance dispersal of individually tagged brush‐turkeys within greater Sydney, observed through the Big City Birds citizen science project. While 84 tagged brush‐turkeys remained within 2 km of their tagging site for the duration of observations, 9 of the tagged birds travelled 8–37 km from their tagging site without returning. This is the first time this dispersal behaviour has been observed in this species and contrasts previous observations of strong site fidelity, suggesting that further research is needed into brush‐turkey dispersal behaviour, particular in urban areas. Our observations demonstrate the value of citizen science methods for long‐term monitoring of individually marked animals, and the potential for the wing‐tagging method to be applied to other charismatic species.

Small farmlands can serve as open habitat for birds in subtropical cities of southern China

AbstractGreenspace or green cover is one of the major factors affecting urban avian diversity. In China, small farmlands producing vegetables are relatively common in cities. Although these farmlands could be a part of greenspaces, their habitat value for birds is rarely known. I investigated how these farmlands influenced winter bird community in two cities of southern China, using the multivariate latent variable model. I considered three green cover types: crop (mostly vegetables), weed (pioneer spontaneous vegetation), and wood (tree/shrub). I calculated the percentage of each green cover at local (50 m radius circular area) and landscape (500 m radius circular area) scales. Of 30 bird species, the abundance of 13 species decreased as crop cover decreased with increasing woody cover at the local scale, whereas the abundance of only two bird species increased with decreasing crop cover. Habitat preference of species mediated these responses, leading to a strong association between the open habit trait and the negative responses. Open habitat bird species richness was also negatively affected by decreasing local crop cover. Tree/shrub bird species richness showed a positive response to decreasing crop cover but the explanatory power of the local scale model was low. Variables at the landscape scale were rarely associated with species abundance or richness. These results suggest that small vegetable‐dominant farmlands can serve as open habitat for birds in urban areas where greenspace largely consists of tree/shrub vegetation. The results also indicate that urban bird diversity is more influenced by local habitat features than landscape‐scale features.

Overwintering in a megacity: Urban green areas and migratory birds in Mexico City

Nearctic-Neotropical migratory birds are threatened by land-use change throughout their complex annual cycles. While urbanization is an essential driver of land-use change, it is unclear how it affects migrant birds. Although migratory birds are more diverse in non-urban patches of native vegetation than in urban areas, neotropical cities can host diverse assemblages of overwintering migrant birds. Migratory birds in neotropical cities tend to be closely associated with urban green areas (UGAs). However, how their presence and abundance are affected by the habitat elements of UGAs and the urban matrix of neotropical cities is poorly understood. In this study, we compared the migratory bird species richness and abundances among UGAs and the urban matrix of the southern section of the megacity of Mexico City and native vegetation sites outside the city. Our results show that UGAs in neotropical cities provide habitats capable of maintaining complex overwintering migratory bird assemblages with local trees as critical features. We also assess the role that UGAs' characteristics play in determining migrant bird assemblages. We conducted bird censuses and measured habitat traits to determine how migrant bird assemblages are related to the habitat features of our study sites. We measured local, buffer, and spatial habitat features of each UGA. We found 23 overwintering migrant species in the three habitats, with 22 present within UGAs. Both UGAs and urban matrix sites had higher estimated species richness of migrant birds than non-urban native vegetation sites located outside the city. Only local features of UGAs affected migrant birds. While tree abundance in UGAs was positively associated with migratory bird species richness, the proportion of tree coverage was positively related to bird abundance. Our results show that UGAs in neotropical cities can maintain complex overwintering migratory bird assemblages, with trees being the most critical habitat feature. As a result, UGA management focused on maintaining trees and increasing their numbers can improve habitat conditions for migratory birds overwintering in neotropical cities.

URBAN SOUTHERN HOUSE WREN (TROGLODYTES MUSCULUS) NESTING IN APPARENTLY UNSUITABLE HUMAN-MADE STRUCTURES: IS IT WORTH IT?

Free-living birds in cities interact with humans and human-made objects. Here, we investigated whether nesting in human-made structures that are physically unstable and prone to frequent human intervention benefits urban Southern House Wrens (Troglodytes musculus). First, we describe the behavior of individuals that repeatedly attempted to nest in a motorcycle helmet (an unsuitable structure) based on ad libitum observations and camera trapping. We also reviewed nesting records of this wren throughout Brazilian cities deposited in crowdsourcing citizen science platforms, such as Wiki Aves, eBird, and iNaturalist. During our field study, in November and December 2019, wrens attempted to build a nest in the helmet for 8 days. Each attempt was interrupted by the removal of the helmet. We recorded 103 videos of nesting activity, including 3 days of high nest-building effort (up to 68 twigs deposited inside the helmet within a 6-h period) and high territory-defense efforts. Both of these behaviors were sometimes followed by one of four types of vocalizations (contact call, complete song, incomplete song, or sub-song). We found 372 Southern House Wren nesting records in online citizen science datasets: 100 were in urban areas with 86 nests built on 24 different human-made structures. Most nests (n = 71) were in what we deemed as stable structures (safe from human intervention) and 34 of them (47.8%) likely bred successfully (i.e., fledglings present). Only seven nests were built on unstable and unsafe structures, and four (57.1%) of these had sufficient evidence of successful nesting. Although nesting in unsuitable places in cities is less-frequent, their breeding success is comparable with nesting in suitable places. Therefore, the nesting of Southern House Wren in human-made structures might benefit the species, even if they eventually become ecological traps due the risk of human intervention. Our study adds knowledge about the life history of the species in urban environments.

Community science data suggest the most common raptors (Accipitridae) in urban centres are smaller, habitat‐generalist species

As the world becomes more urbanized, identifying traits that allow some species to thrive in cities will be key to predicting which species will probably remain common and which may require conservation attention. Large, diverse, widely distributed and readily documented raptors represent an ideal taxonomic group to understand how species persist and thrive in urban areas. Global community science datasets can reveal patterns that might be obscured in studies limited to a small number of locations, those relying on presence/absence data or those conducted by a small number of observers. We analysed 127 species of raptors (hawks and related species; Family: Accipitridae) using recent community‐science (eBird) records from 59 cities on five continents, modelling two indices of occurrence with five ecological and life history traits, and incorporating phylogenetic relatedness. Based on previous studies of avian traits in urban vs. rural populations, and well as our casual observations of birds in cities across the USA and around the world, we hypothesized that urban raptor communities would be dominated by smaller, ecological‐generalist species regardless of the regional species pool. We defined urban occurrence in two ways: urban abundance (the frequency of breeding season reports within 10 km of a city centre) and species proportion (the relative abundance of each species in the local raptor community). We did not detect a strong phylogenetic signal for either urban occurrence index, suggesting that various unrelated raptor species may become common in cities of the world. In the best‐performing models, both urban indices were significantly negatively associated with body mass, and significantly positively associated with habitat breadth; species proportion was also significantly associated with nest substrate breadth. Our analysis suggests that there may be an ‘archetypal urban raptor’ and that species lacking these traits (e.g. large, specialist taxa) may be at greater conservation risk as global urbanization increases.

Theoretical aspects of the calculation the main design parameters of the electric bird repeller

The problem of scaring away birds was born in ancient times and remains relevant to this day. Birds tend to places where they are comfortable and stay there. Therefore, to achieve maximum effect, new and effective designs of electric bird repellers are needed. Currently, the territories of cities and their outskirts serve as a habitat not only for people and domestic animals, they are also a habitat for numerous species of wild birds. In the settlements and in their vicinity, a specific fauna of birds has formed. Its main features are a limited number of species and a large number of individuals. This is due to the fact that few bird species were able to adapt to the specific living conditions in the city. However, those who were able to adapt found in the city a favorable environment for rapid and mass reproduction. The number of synanthropic birds in large cities reaches tens and hundreds of thousands of individuals [2]. Synanthropic birds are wild birds that constantly live in the vicinity of humans or have found favorable nesting conditions in the territory of settlements and their environs. Many spheres of life of synanthropic birds are directly related to human activities, since the food of synanthropic birds is anthropogenic in nature, because their diet usually includes seeds of cultivated plants and all kinds of food waste [3]. In each region, different species of birds prevail, but there are patterns that are characteristic of the entire territory of Russia. Almost everywhere, the main representatives of the synanthropic are house sparrows and doves. In the central part of the country, you can safely add the hooded crow to this list. When moving towards the west, the number of crows decreases markedly.

How Do Birds Sing Over City Noise?

Have you ever raised your voice because someone could not hear you? Imagine talking to a friend in a peaceful park. Now imagine trying to talk on a busy street or near a highway. The traffic noise makes it difficult to communicate, and you may speak up so your friend can hear you. Other animals have this issue, too. Songbirds can live in various environments, such as forests and grasslands, and they use their songs to communicate with each other. As cities grow and invade their habitats, birds may find it harder to hear one another. To be heard, some birds might change their songs. For example, some birds in cities sing louder, longer, or at a higher pitch than rural birds. Researchers are studying this problem: how does human-made noise affect birdsong? Answering this question is important so we can protect the birds around us and their habitats.

A green design of city squares increases abundance and diversity of birds

Cities are designed for humans but are also highly dynamic ecosystems that provide habitats for wild animals. These habitats depend on a city's green infrastructure which is increasingly threatened by urban densification. A commonly studied model taxon for wild animals in cities are birds, and the importance of large green spaces for the diversity of birds in cities has been shown. However, how small-scale green spaces affect bird communities, which local characteristics are important, and whether there are seasonal differences remains unclear. We asked how and to what extent the characteristics of city squares in Munich affect the diversity and abundance of birds and if there are differences between bird communities in spring, autumn, and winter. We monitored birds on 103 city squares in Munich using a search-route method. Sampled squares spanned a spatial gradient from the center to the periphery of the city and differed in sealed surface proportion and vegetation structures, such as trees, shrubs, and lawns. The diversity and abundance of birds increased with a higher proportion of green characteristics on the square. Especially the proportion of grass cover and the density of trees had strong positive effects. Old trees had additional effects on birds beyond the effects of trees in general, while the mean number of people on a square negatively influenced bird abundance and diversity. Despite seasonal changes in bird composition, square characteristics showed consistent effects on bird abundance and diversity over seasons. These results underline that the green characteristics of city squares, and therefore of small-scale green spaces, affect their suitability as habitat for wildlife in cities. Integrating this knowledge into city planning can help to maintain or even increase urban biodiversity in the future.

Eat yourself sexy: how selective macronutrient intake influences the expression of a visual signal in common mynas.

Producing colored signals often requires consuming dietary carotenoid pigments. Evidence that food deprivation can reduce coloration, however, raises the question of whether other dietary nutrients contribute to signal coloration, and furthermore, whether individuals can voluntarily select food combinations to achieve optimal coloration. We created a two-way factorial design to manipulate macronutrient and carotenoid access in common mynas (Acridotheres tristis) and measured eye patch coloration as a function of the food combinations individuals selected. Mynas had access to either water or carotenoid-supplemented water and could either eat a standard captive diet or choose freely between three nutritionally defined pellets (protein, lipid or carbohydrate). Mynas supplemented with both carotenoids and macronutrient pellets had higher color scores than control birds. Male coloration tended to respond more to nutritional manipulation than females, with color scores improving in macronutrient- and carotenoid-supplemented individuals compared with controls. All mynas consuming carotenoids had higher levels of plasma carotenoids, but only males showed a significant increase by the end of the experiment. Dietary carotenoids and macronutrient intake consumed in combination tended to increase plasma carotenoid concentrations the most. These results demonstrate for the first time that consuming specific combinations of macronutrients along with carotenoids contributes to optimizing a colorful signal, and point to sex-specific nutritional strategies. Our findings improve our knowledge of how diet choices affect signal expression and, by extension, how nutritionally impoverished diets, such as those consumed by birds in cities, might affect sexual selection processes and, ultimately, population dynamics.

Cryptosporidium of birds in pet markets in Wuhan city, Hubei, China

Cryptosporidium is a group of protistan parasites of a range of vertebrates including mammals and birds. Stimulated by previous work that revealed “zoonotic” Cryptosporidium meleagridis subtypes (i.e. IIIbA26G1R1b and IIIbA22G1R1c) in diarrhoeic children and domestic chickens in Wuhan city and environs in Hubei Province, China, here we explored whether zoonotic C. meleagridis subtypes might also occur in pet birds in Wuhan city. From 11 bird markets in this city, we collected 322 faecal samples from 48 species of birds (representing six taxonomic orders), isolated genomic DNA and then conducted PCR-based sequencing of genetic markers in the small subunit (SSU) of the nuclear ribosomal RNA and the 60 kDa glycoprotein (gp60) genes of Cryptosporidium. Using SSU, Cryptosporidium was detected in 55 (17%) of the 322 samples. Cryptosporidium avium, C. baileyi, C. meleagridis, C. muris and C. proventriculi were characterised in 18%, 47%, 11%, 2% and 20% of the 55 samples, respectively, and a novel Cryptosporidium galli-like taxon in one sample. Using gp60, only one subtype (IIIeA17G2R1) of C. meleagridis was identified, which had not been detected in a previous study of diarrhoeic children in Wuhan. However, IIIe subtypes have been found in both humans and birds around the world. The relatively high prevalence and genetic diversity of Cryptosporidium recorded here in pet birds raise awareness about possible reservoirs of zoonotic variants of Cryptosporidium in birds in Wuhan, and potentially, other provinces in China.

Chronic exposure to urban noise during the vocal learning period does not lead to increased song frequencies in zebra finches

It has often been observed that birds sing at a higher pitch in cities and other areas that are polluted with intense low-frequency noise. How this pattern arises remains unclear though. One prevailing idea is that songbirds adjust song frequencies to environmental noise profiles through developmental plasticity via vocal learning. However, the conclusions of previous studies testing this hypothesis are inconsistent. Here we report the findings from two song learning experiments with zebra finches (Taenopygia guttata), in which we exposed young birds to anthropogenic noise during their sensitive vocal learning period. Unlike previous studies that addressed this issue, we did not use constant synthetic noise but natural urban noise with its typical amplitude fluctuations that was broadcast at realistic sound levels. We found that noise-exposed males in neither experiment developed higher pitched songs compared to control males. This suggests that the natural fluctuations between higher and lower noise levels in cities may allow young birds to exploit relatively quiet moments to hear their tutors and themselves, permitting them to make accurate copies of even low-frequency song elements.Significance statementIf animals are to persist in urban habitats, they often must adjust their behavior to the altered conditions. Birds in cities are often observed to sing at a higher pitch, but we are largely ignorant of how this phenomenon arises. We investigated whether low-frequency traffic noise interferes with the song learning of birds so that they develop higher pitched songs. Accordingly, we played back natural traffic noise from urban bird habitats to young birds during their learning period and then analyzed their adult songs. We found that birds that learned their songs in noise did not sing at higher frequencies compared to control males that learned their song with no noise exposure. Our results show that typical traffic noise in cities may not be sufficient to interfere with vocal learning in a way that birds develop higher-pitched songs.