Use Of Playback Research Articles

Mimetic Dimensions of Bird-Human Interactions: The Use of Bird Sound Imitations among Estonian Birders

Abstract This paper explores bird sound imitation as a particular type of interspecies interaction. Using questionnaires, interviews, and participatory observations, a survey was conducted among Estonian birders to find out about the prevalence of the practice, the diversity of imitated species, the means of imitation, and the attitudes of birders towards the use of recordings in the field. The study found that 55 species of birds from 11 orders were imitated and using one’s own voice was the most common way of imitating birds. The choice of the method of imitation depended on the purpose and context of imitation. Most birders supported the use of playbacks for scientific purposes, but not for daily birding. With the easy availability of playback technologies, there are increased concerns about the ubiquitous presence of disturbing factors. At the same time, however, the technological boundlessness is balanced by the heightened ethical self-reflection of birders.

The acoustic playback technique in avian fieldwork contexts: a systematic review and recommendations for best practice

Acoustic playback is commonly used to study wild birds, with applications as diverse as investigating behaviours, ascertaining the presence of rare and elusive species, and attracting individuals to a location. The number of studies employing playback is growing larger every year because it is easy to apply, increasingly affordable and very effective. However, the way that it is used and reported varies significantly across researchers and species. This lack of a protocol for reporting acoustic playbacks inevitably slows the progress of the field, as studies cannot be easily compared. In 1991, some of the most knowledgeable researchers in the field of animal communication met at a North Atlantic Treaty Organization (NATO) Advanced Research Workshop (ARW) at Thornbridge Hall in the UK to consider the design of playback experiments. The proceedings of the meeting were published in 1992 and contain crucial guidelines regarding this use of playback. In this paper we review the literature for papers published since that milestone that use acoustic playback in ornithological fieldwork contexts. We use the RepOrting standards for Systematic Evidence Syntheses (ROSES) to evaluate the description of the methods used. The main goal of this review paper is to identify a shared set of rules for employing and reporting the playback technique in such contexts to promote reproducibility and comparability. We found 625 peer‐reviewed articles in three on‐line databases, of which 419 reported field (rather than captive) studies employing avian playback. The biggest hindrance to reproducibility is the availability of the acoustic tracks used by authors; 4% (15 articles) of our sample made their tracks publicly available. We found that only one article provided enough details for their playback application to be fully reproducible. Further, only five articles (0.92%) provided enough information for reproducibility, even if we assume information about track preparation and recording details to be unnecessary when tracks are available. Based on our synthesis of the literature, we provide a set of recommendations for the reporting of playback uses to promote reproducibility, including sample paragraphs of description as supplementary material. We strongly recommend that tracks used for such experiments are deposited in dedicated on‐line repositories for the use of other researchers. While our focus is avian fieldwork applications of the playback technique, we believe that our findings can be easily transferred to other animal systems subject to acoustic playback.

Brasilia tapaculo (Scytalopus novacapitalis) seasonality and site occupancy in altitudinal riparian environments after non-natural burnings and feral pig invasion in Serra da Canastra National Park, Brazil.

The Brasilia Tapaculo, Scytalopus novacapitalis Sick, 1958, is a rare, geographically restricted, and endangered bird species that inhabits riparian vegetation of Cerrado, mainly Gallery Forests. In Serra da Canastra National Park, southeastern Brazil, wetlands are under threat due to frequent non-natural burnings and invasion by feral pigs, Sus scrofa, Linnaeus, 1758. We aimed to evaluate the possible effects of seasonal variations on S. novacapitalis records in undisturbed habitats and answer questions about how fire and feral pigs may affect site occupancy of the species. Transects alongside riparian environments were used to survey n=21 sites, totalizing 7.5 Km, from 2014 to 2019. Results indicated the season influenced both, spontaneous records and induced encounters by playback method, which were more abundant in breeding period, from early spring to summer. The use of playback significantly increased the amount of records in all seasons. The probability of site occupancy in all studied area was higher in late spring (ψ=0.91) and lower in autumn (ψ=0.73). In burned sites (n=8), the first post-fire month showed the lowest probability of occupancy, but there was a rapid recovery in 2nd month and stabilization similar to control area from the 3rd month ahead. After sites (n=11) were invaded by feral pigs, the estimation of site occupancy indicated a slight drop in first two months, but after the 3rd month of invasion the decreasing pattern enhanced the discrepancy with undisturbed areas. It is important to keep monitoring S. novacapitalis population and their threats, to subsidize management actions, especially to avoid frequently unusual burnings in riparian forests, and to block the access of feral pigs to wetlands.

Playback: An Investigation of the Discursive Implications and the Pragmatic Functions of Repetition in Traditional Chinese Medical Consultations

The current study examined a role-related difference in the use of playback (one form of repetition) in medical discourse. We adopted a language and social psychology approach and invoked communication accommodation theory (CAT) to explore this discourse. Thirty doctor/older adult dyads were recorded and transcribed verbatim. Findings suggested that the deployment of repetition is a strategy used by the addresser to either complement or converge to the other interlocutor, in order to ensure that the medical instrumental task is efficiently accomplished and interpersonal rapport is established. Our results show that discourse management is the dominant strategy used by speakers when playing back the other’s utterances. Our analysis also demonstrates that CAT strategies work interdependently. We conclude that CAT is a valuable framework to elucidate the dynamics of, and the social psychological processes underlying, the practice of repetition in medical interviews.

Distribución y abundancia del cardenal amarillo (Gubernatrix cristata, Passeriformes: Thraupidae) en el sur de la provincia de Buenos Aires

The Yellow Cardinal ( Gubernatrix cristata ) is an endangered species distrib- uted mainly in the South American Espinal. In Buenos Aires province it is mainly distributed in the departments of Bahia Blanca, Puan, Villarino and Patagones. The knowledge about its current distribution, population status and habitat use is currently scarce. This work makes an approximation to the knowledge of the current status of the populations of the species in the south of Buenos Aires, contributing new data on its distribution, abundance and on forest use. We performed 303 independent extensive, unlimited, radio sampling points with the use of playback over 13 transects, totaling 1,183 km between 2015 and 2017, during 11 sampling campaigns. The percentage of forest cover was estimated at each point within 100 m radius. We obtained 19 records of a total of 48 individuals: 24 males, 17 females, and 7 undeterminated individuals. The 78,9 % of records and the 83,3 % of individuals were observed in the southern area. Forest cover was similar between sites with and without Yellow Cardinal records. The low records at the North and Centre areas could be due to the illegal capture of individuals, as long as the species has been abundant in the past, but not sought, otherwise the species may have always been scarce in these areas.

Estimating primate population densities: the systematic use of playbacks along transects in population surveys.

Accurate measures of animal population densities are essential to assess their status, demography, and answer ecological questions. Among several methods proposed to collect abundance data, line transect sampling is used the most. The assumptions required to obtain accurate density estimates through this method, however, are rarely met when studying primates. As most primate species are vocally active, density estimates can be improved by associating transect sampling with playback point counts to scan the entire study area. Yet, attention to playback procedure and data collection design is necessary. Here, we describe a protocol to assess primate densities using playback and test its application on surveys of Callicebus nigrifrons, a small Neotropical primate that shows site fidelity and active vocal behavior. We list important steps and discuss precautions that should be considered, from the adjustments in the recordings in the lab to field procedures in the playback broadcasting sessions. Prior to the surveys, we conducted playback trials with three habituated wild groups at three forest remnants to test their response to the playback stimuli at different distances. Based on these trials, we defined the radius distance covered by the playback sessions. Then, we conducted two surveys in 12 forest remnants, in the northeast of São Paulo State Brazil. The results of density estimates were consistent between the two surveys. As the playback survey protocol we described has proved to be a simple and useful tool for surveying vocal primate and generated reliable data, we suggest that it is a good alternative method to estimate density of species, particularly for those that are responsive to playbacks and show site fidelity.

New records, reconfirmed sites and proposals for the conservation of black lion tamarin (<i>Leontopithecus chrysopygus</i>) in the middle and upper Paranapanema


 
 
 The Black Lion Tamarin (BLT, Leontopithecus chrysopygus) is an endangered species, endemic to the State of Sao Paulo, Brazil. The conservation of the species depends on the effective management of the populations and forest conservation but also on the updated knowledge of its areas of occurrence. Here, we report the record of a new site of BLT occurrence in the municipality of Guareí and confirm the presence of this species in two municipalities, Taquarivaí and Borebi, which (Borebi) is the first record since the last two decades in the Middle Paranapanema basin. Direct observations of BLT groups occurred after the use of playbacks of BLT vocalizations (Guareí), during the prospection of the area (Taquarivaí) and the monitoring of the fauna (Borebi). These three sites are located close to known BLT populations. The occurrence of BLTs in anthropized landscapes with low forest cover, but with a considerable presence of riparian forests, gives evidence of the ecological resilience of the species and underlines the conservation value of such habitats. We are initiating scientific based projects and environmental education programs to increase the knowledge about the ecology and tolerance of BLTs in human altered landscapes. The confirmation of occurrence areas and new records of BLT populations is the starting point for the conservation success of the species.
 
 

Biases associated with the use of a playback in stopover ecology studies of Bluethroats Luscinia svecica

Capsule The effects of playback use on number of captures, recaptures, fuel load, and age and sex ratios, and so potential bias in stopover studies in migrant Bluethroats was investigated. Playback promoted biases in the number of captures (although this was site-dependent) and fuel load. We strongly advise against the systematic use of playback to sample Bluethroats at constant effort sites or other type of ringing station, especially if studying fuel loads.

No Sex Bias in Wood Thrushes (Hylocichla mustelina) Captured by Using Audio Playback during the Non-breeding Season

ABSTRACT Conservation of migratory songbird species requires information on abundance and survival over the annual cycle, including from overwintering sites. Broadcasting recorded calls or songs (playback) often increases detections or capture rates of birds, and can improve estimates of abundance or survival. Wood Thrushes overwintering in Belize regularly respond to broadcasted conspecific vocalizations (songs); however, it is unknown if song attracts a specific age, sex, or size class of birds. Our goal was to determine if the use of playback resulted in sex, age, or size-biases in captures of Wood Thrushes, relative to captures without playback, at a non-breeding site in Belize, Central America. We predicted that birds responding to playback would be: (1) male, (2) adults, and (3) larger than birds caught without playback, owing to social dominance of larger adult males over juveniles and females. Surprisingly, we found no significant difference in sex or age ratio, or body size of birds captured with...

Optimizing Repeat-Visit, Call-Broadcast Nocturnal Surveys for Yellow Rails (Coturnicops noveboracensis)

Due to its secretive nature and nocturnal vocalization, multi-species bird monitoring programs are not effective in surveying populations of Yellow Rails (Coturnicops noveboracensis) and, thus, species-specific survey methods should be used. To determine how to optimize nocturnal call-playback surveys of Yellow Rails, we evaluated the effects of survey methods (naïve-estimated vs. detectability-adjusted estimated occupancy, observer, number of surveys, and the use of playbacks) and temporal and environmental conditions (e.g., time, date, temperature, moon phase, seasonality, and cloud cover) on detection probability. In 2010 and 2011, 334 call-broadcast night surveys for Yellow Rail were conducted at 167 survey points within 80 wetlands in south-central Manitoba, Canada. Yellow Rail detection probability was estimated at 0.63 in both years. In 2010, the detectability-adjusted wetland occupancy rate was estimated at 0.63, and in 2011 it was estimated at 0.36. Call-broadcast surveys contributed relatively little to improving Yellow Rail detectability, but repeat surveys at each site increased the number of individuals detected. Detection probability was not correlated with the temporal or environmental variables we studied, or by observer. Surveys where call-broadcasts are not feasible, such as volunteer surveys, are still likely to result in good estimates of Yellow Rail abundances, if surveys are repeated within breeding seasons.

Rare or elusive? A test of expert knowledge about rarity of Amazon forest birds

AbstractAimTo offer a test of expert knowledge about rarity of twenty Amazon forest bird species following an approach that equates rarity with low site occupancy and formally accounts for imperfect species detection. We define ten pairs of closely related species, each pair with one hypothetically common and one hypothetically rare species. Our null hypothesis is that members of each pair have similar occupancy, with hypothesized differences due to detection errors alone.LocationA 1000‐ha plot of primary rainforest in the central Brazilian Amazon.MethodsWe visited each of 55 sampling sites multiple times per season for three field seasons and estimated the probability of site occupancy by each species following a maximum likelihood state‐space approach that also estimates the probability that a species is present yet undetected at a site. To maximize detection and account for its variation, we employed three different sampling techniques while systematically training and testing observer's ability to recognize species.ResultsOccupancy estimates agree with expert predictions in all but two species pairs and show no evidence of clear temporal variation in occupancy between sampling seasons. Detection probability had a positive relation with observer ability, a strong relation to time of day across species, and a strong relation with the use of playback for some species. Detection with point counts and with autonomous recorders varied between species pairs.Main conclusionsWe reject the null hypothesis of equal occupancy within pairs, concluding that expert knowledge on species rarity is useful and worth eliciting. Our results replace qualitative ratings of rarity with statistical estimates of occupancy, establishing a reliable baseline for future comparisons. Besides illustrating the relevance of expert knowledge, this application to Amazonian birds illustrates a flexible approach that can be used for testing knowledge about rarity for a variety of species groups and spatial scales.

Does the use of playback affect the estimated numbers of red–legged partridge Alectoris rufa?

The red–legged partridge Alectoris rufa lives in a situation of potential conservation risk for its long–term preservation in Italy as its habitat is increasingly threatened by the disappearance of traditional agriculture–related environments. In such a situation, it is important to use effective and appropriate monitoring methods to assess population changes over time and to identify potential conservation threats. The objective of this study was to evaluate the effectiveness of the playback method to estimate the density of calling males. We compared playback method with spontaneous calling of males at dawn and direct observations along transects. The results on raw count data of playback counts revealed a strong underestimation rate compared to the method that gave the best results: count of spontaneous calls at dawn. Our study provides a critical evaluation of a method that is widely used even though data about its effectiveness are scarce. Our data do not evaluate detection probability of the three methods. Our aim was only to evaluate which methods give the best results in term of population size estimation under the same field condition (same population density, same period, same monitoring area). The results raise some doubts about the ability of the playback method to monitor red–legged partridge populations. The implications of our results for red–legged population management are discussed.

Survival rates of adult European Nightjars Caprimulgus europaeus breeding in northwestern Italy

Survival rates of breeding adult European Nightjars were estimated from capture–mark–recapture data, collected from 1997 to 2009 at a ringing station in northwestern Italy. Birds were trapped without the use of playback. A sample of 109 European Nightjars, obtained with mist-nets operated each year during the May to July breeding period, provided 158 capture events. Survival and recapture probabilities were estimated with program MARK, and the effects of some climatic factors (local and Sahelian rainfall and NAO) were tested. Overall, variation in survival rates was not clearly associated with any of the climate factors considered, but variation in these over the period was relatively low and the power to examine inter-annual variation in survival was also low. Finally, the time- and sex-independent model gave an annual survival rate of 0.70 ± 0.05 (se), with sex-dependent recapture probabilities which were lower for females (0.19 ± 0.05) than for males (0.35 ± 0.07).

Novel survey method finds dramatic decline of wild cotton-top tamarin population.

The cotton-top tamarin (Saguinus oedipus) is a critically endangered primate, endemic to the tropical forests of Colombia. Population monitoring is essential to evaluate the success of conservation efforts, yet standard survey methods are ineffective because animals flee silently before they are seen. We developed a novel technique that combines the use of playbacks of territorial vocalizations with traditional transect surveys. We used remote sensing to identify potential habitat within the species' historic range, and visited the 27% that we could survey safely. Of this, only 99 km(2) was extant forest, containing an estimated 2,045 animals (95% confidence interval 1,587-2,634). Assuming comparable densities in non-surveyed areas, approximately 7,394 wild cotton-top tamarins remain in Colombia. With 20-30,000 animals exported to the United States in the late 1960s, this must represent a precipitous decline. Habitat destruction and capture for the illegal pet trade are ongoing. Urgent conservation measures are required to prevent extinction in the wild.

Does the Use of Playback Affect the Estimates of Numbers of Grey Partridge Perdix perdix?

Methods of estimating bird numbers differ with regard to the results obtained and time required. A usual method of counting grey partridge Perdix perdix consists in counting calling males in the period with their highest vocal activity. This method was tested in our study with the additional use of playback. The number of males calling after playback was significantly higher than before playback. We found a positive relationship between the increase in the number of males calling after playback and their maximum numbers at the study site. However, after playback, the mean number of recorded males was significantly smaller in sites with the presence of red fox Vulpes vulpes burrows than in locations where this predator was absent. Without playback, there was no difference in the number of males between these two types of sites. The results of this study show that the use of playback improves the ability to detect grey partridges (as was similarly found with many other species). The use of playback in estimating the numbers of grey partridge may also allow further analyses, on e.g. site selectivity.

Detection probability of Golden-winged Warblers during point counts with and without playback recordings

ABSTRACT Use of point-count data to estimate population sizes of North American landbirds may be challenged by limitations on detection probability of particular species, thereby requiring correction factors to ensure accurate estimates. We estimated detection probability of Golden-winged Warblers (Vermivora chrysoptera) during 3-min point-count surveys conducted both with and without use of playback recordings in a mixed shrubland-forest habitat (clearcut area) and a 60-m wide electric transmission line right-of-way (ROW) in central Pennsylvania from 20 May to 17 June 2002–2003. In addition, we assessed the value of playback with respect to response rates of warblers and distance within which warblers approached the observer. Without playback, detection probability was approximately 23% in the clearcut area and 61% in the ROW. Use of playback resulted in 7% and 19% net increases in probability at the clearcut area and the ROW, respectively; proportional increase was approximately 30% for both habitats. Warblers responded to playback 68% of the time, but response rate was greater within 100 m (72%) than beyond (53%). Most responses (85%) included approach of the warbler toward the observer, and most individuals approached within 10 m. We conclude that 3-min point counts with playback do not yield detection probabilities sufficient to estimate population size of Golden-winged Warblers without use of correction factors. Furthermore, detection probability in mixed shrubland-forest habitats can be much lower than in linear habitats such as utility ROWs. Efforts to estimate population size of Golden-winged Warblers from data of the North American Breeding Bird Survey should recognize that habitat structure has much influence on detection probability as it relates to distance at which an observer can hear (or see) warblers. Accordingly, we recommend that such efforts incorporate a maximum detection distance of 100–150 m in mixed shrubland-forest habitats.

Group Living in the Black-Breasted Wood-Quail and the Use of Playbacks as a Survey Technique

Abstract I used playbacks of recorded group song to survey and capture Black-breasted Wood-Quail (Odontophorus leucolaemus), a cloud forest endemic, in Monteverde, Costa Rica. This species is abundant in the dense understory of large windbreaks, forest fragments, and continuous forest of the Monteverde Reserve Complex. Mean covey size was four adults (range = 2–9 adults) and mean density, which did not differ between fragmented and continuous forest, was one covey per 3.3 ha. Wood-Quail defended all-purpose group territories and coveys persisted from one year to the next, indicating a group structure that is very different from what is found in most New World quail. A peak in breeding activity occurred at the transition from the wet to the dry season and larger groups produced significantly more juveniles than smaller groups in this population. Playbacks were a useful technique for detecting Black-breasted Wood-Quail; coveys responded to 65% of survey attempts by chorus and approach. By repeating the survey just three times, I was able to detect 91% ± 5% of all coveys that were known from extensive searches to occur in the remnant forest patches of the Monteverde community. The year-round sociality that is seen in this species is due in part to the retention of young on the natal territory beyond the age of sexual maturity. The intriguing relationship between group size and reproductive success in this population suggests the wood-quail may provide the first demonstration of a cooperative breeding system in the Galliformes.

Group Living in the Black-Breasted Wood-Quail and the Use of Playbacks as a Survey Technique

Abstract I used playbacks of recorded group song to survey and capture Black-breasted Wood-Quail (Odontophorus leucolaemus), a cloud forest endemic, in Monteverde, Costa Rica. This species is abundant in the dense understory of large windbreaks, forest fragments, and continuous forest of the Monteverde Reserve Complex. Mean covey size was four adults (range = 2–9 adults) and mean density, which did not differ between fragmented and continuous forest, was one covey per 3.3 ha. Wood-Quail defended all-purpose group territories and coveys persisted from one year to the next, indicating a group structure that is very different from what is found in most New World quail. A peak in breeding activity occurred at the transition from the wet to the dry season and larger groups produced significantly more juveniles than smaller groups in this population. Playbacks were a useful technique for detecting Black-breasted Wood-Quail; coveys responded to 65% of survey attempts by chorus and approach. By repeating the surv...

A Comparison of Census and Monitoring Techniques for Leach’s Storm Petrel

Abstract Leach’s Storm Petrel (Oceanodroma leucorhoa) is a difficult species to census because the birds nest in burrows, are nocturnal, and spend most of their life at sea, only coming ashore to breed. Simply locating a suspected petrel burrow is inadequate for management and conservation purposes because it is not known if the burrow is in use. The traditional method, of “grubbing”, or reaching into suspected burrows to determine occupancy, is invasive, and of limited accuracy. Playback of specific calls during the nesting period may be used to check for burrow occupancy. I conducted a test of grubbing in comparison with vocal playbacks and use of a portable video camera to determine which methodology was most accurate, least invasive and most efficient in time and cost investment. The use of playbacks showed the most promise as a quick, low cost method for surveying these burrowing petrels. The camera method, though as thorough as the playbacks, was more expensive and time consuming, while the traditio...

The breeding biology of the Critically Endangered Seychelles Scops-owl Otus insularis: consequences for conservation and management

The endemic Seychelles Scops-owl Otus insularis is a Critically Endangered restricted-range species currently recorded only from the montane forest of Mahé, the largest (152 km2) and highest (903 m) island in the granitic Seychelles. Limited research has been conducted on the species and, in particular, details of its breeding biology are poorly known. Behavioural observations were made on 12 pairs by the systematic monthly use of playback of conspecific calls, in conjunction with frequent non-playback territory visits from April 1999 to May 2001. A total of eight nests, including the first nest record, were found on three territories. All were in tree cavities (7–25 m high) and contained either a single egg or chick. This was consistent with additional observations of solitary fledglings (n = 11, from eight territories). Incubation lasted 3–4 weeks and the fledging period was 4–6 weeks (data from two nests). The timing of copulations, in conjunction with the detection of nests and fledglings, suggests that the scops-owl can breed throughout the year with peaks in nesting occurring around May and October. Sex roles during breeding were similar to those of other Strigidae owls: incubation was performed by the female; males courtship-fed the female prior to and during incubation, and the female and chick for the first 2 weeks post-hatching; and both parents fed older chicks and fledglings. Fledglings remained on territory for at least 3 months. Breeding success of study pairs was low: two of eight nests were successful and 11 fledglings (recorded from eight of 12 study territories) were observed in a 26-month period, equivalent to c. 0.5 fledglings per territory per year. Evidence suggests that alien predators may have been a factor limiting breeding success. We discuss the conservation implications of our findings.