Male Calling Behavior Research Articles

Social regulation of androgenic hormones and gestural display behavior in a tropical frog

Many animals use forms of gesture and dance to communicate with conspecifics in the breeding season, though the mechanisms of this behavior are rarely studied. Here, we investigate the hormone basis of such visual signal behavior in Bornean rocks frogs (Staurois parvus). Our results show that males aggregating at breeding waterfalls have higher testosterone (T) levels, and we speculate that this hormone increase is caused by social cues associated with sexual competition. To this end, we find that T levels in frogs at the waterfall positively predict the number waving gestures—or “foot flags”—that males perform while competing with rivals. By contrast, T does not predict differences in male calling behavior. In these frogs, vocal displays are used largely as an alert signal to direct a rival's attention to the foot flag; thus, our results are consistent with the view that factors related to reproductive context drive up T levels to mediate displays most closely linked to male-male combat, which in this case is the frog's elaborate gestural routine.

Excitatory and inhibitory interactions affect the balance of chorus activity and energy efficiency in the aggregations of male frogs: Numerical simulations using a hybrid dynamical model

We numerically study the role of excitatory and inhibitory interactions in the aggregations of male frogs. In most frogs, males produce sounds to attract conspecific females, which activates the calling behavior of other males and results in collective choruses. While the calling behavior is effective for mate attraction, it requires high energy consumption. In contrast, satellite behavior is an alternative mating strategy in which males deliberately stay silent in the vicinity of a calling male and attempt to intercept the female attracted to the caller, allowing the satellite males to reduce their energy consumption while having a chance of mating. Here we propose a hybrid dynamical model in which male frogs autonomously switch among three behavioral states (i.e., calling state, resting state, and satellite state) due to the excitatory and inhibitory interactions. Numerical simulations of the proposed model demonstrated that (1) both collective choruses and satellite behavior can be reproduced and (2) the satellite males can prolong the energy depletion time of the whole aggregation while they split the maximum chorus activity into two levels over the whole chorusing period. This study highlights the importance of the multiple behavioral types and their transitions for the performance of the whole aggregation.

Disease influences male advertisement and mating outcomes in a critically endangered amphibian

The sublethal effects of infectious disease on reproductive behaviour and mating success are not well understood. Here, we investigated predictors of male mating success in one of Australia's most critically endangered vertebrates: the northern corroboree frog, Pseudophryne pengilleyi. Using a genomic approach to assign parentage, we explored whether infection with the amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), a pathogen responsible for amphibian declines globally, influenced male calling behaviour and mating success. We also explored whether male mating success was predicted by phenotypic traits (age, body size, coloration, call characters) that potentially signal genetic quality, and the soil moisture (water potential) of male-constructed terrestrial nests, which may directly impact offspring survival. We found that Bd significantly influenced male advertisement; Bd-infected males produced calls with significantly higher pulse repetition rates than uninfected males. Older males had a higher probability of mating; however, variation in the number of eggs in a nest was most strongly explained by an interaction between male Bd infection status and call pulse repetition rate. We propose that these relationships may result from either pathogen-mediated changes to host behaviour or host-mediated changes to behaviour (e.g. terminal investment). Regardless of the mechanism, this is the first evidence that male mating success in an amphibian can be influenced by male Bd infection status, highlighting a novel mechanism through which this virulent pathogen can affect amphibian fitness. More broadly, these findings add to a growing body of evidence that pathogens can alter the reproductive biology of their hosts. From a conservation perspective, increased consideration of how sexual selection operates in altered environments has the potential to assist with the management of threatened amphibians worldwide.

Spatio-temporal distribution of sexual calling behaviour in domesticated, sterile and wild Queensland fruit fly males under field cage conditions.

The sterile insect technique (SIT) is used in Australia to contain and eradicate outbreaks of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) in fruit-fly-free regions, and to manage populations in some endemic regions. To assess the likely impact of SIT on wild B. tryoni populations it is important to assess the colocation and synchrony of male calling between sterile and wild flies. We observed the location and timing of calling behaviours of marked mass-reared (fertile and sterile) and wild B. tryoni males in walk-in field cages. We found that wild males called further from the canopy centre than mass-reared (fertile or sterile) males. Mass-reared (fertile or sterile) males called earlier in the evening than wild males and, consequently, mass-reared males called when temperature and light intensity were higher than when wild males called. Male calling is a prerequisite to mating among dacine fruit flies. Therefore, our observations of spatio-temporal divergence in male calling behaviour may lead to assortative mating between mass-reared and wild B. tryoni in SIT applications. The importance of these spatio-temporal differences warrants further inquiry, with particular focus on how environmental conditions modify calling behaviour and avenues to ameliorate differences between sterile and wild flies. © 2021 Society of Chemical Industry.

Acoustic Signal Diversity in the Harlequin Toad Atelopus laetissimus (Anura: Bufonidae)

The acoustic signals in Atelopus (Anura: Bufonidae), a Neotropical genus currently composed of 97 species, are poorly known. In this study, we describe for the first time, the advertisement, release, and agonistic calls of Atelopus laetissimus, an endangered species endemic to the Sierra Nevada de Santa Marta, in northern Colombia. The calling behavior of males was associated with reproduction (advertisement calls) and male–male aggression (agonistic and release calls). We also describe, for the first time, calls from female A. laetissimus, constituting the first case of a female's vocalization in the genus, recorded while one male was trying to clasp her. The diverse acoustic signals described here for Atelopus laetissimus suggest the vocal repertoire in the genus Atelopus may be more complex than is currently realized.

Staying ahead of the game—plasticity in chorusing behavior allows males to remain attractive in different social environments

The dynamic nature of many breeding aggregations, where the composition and attractiveness of a male’s competitors are ever changing, places extreme pressure on advertising males to remain competitive. In response to this challenge, males may adjust the properties of their calls or change when they signal relative to their nearest neighbors, which are likely their strongest competitors. We used two playback experiments—one simulating a conspecific environment and the other simulating a mixed-species environment—to test the hypothesis that males use social plasticity in signal features, signal timing, or both, to remain attractive. Further, we examined whether this plasticity is mediated by selective attention, through which males change calling behavior in response to the most relevant competitors, while disregarding less relevant rivals. We find that males change some temporal call features, but rely strongly on signal timing to remain attractive relative to rivals. Simultaneous assessment of both types of calling plasticity allowed us to makes sense of counterintuitive responses of male calling behavior that would otherwise appear non-adaptive. We further show that this plasticity is most pronounced in response to attractive/conspecific males. We discuss how sexual selection by female choice may influence the trade-off between call feature and call timing plasticity, as well as how competitive interactions on a local scale may affect the overall acoustic environment in the chorus. Males of group-signaling species face intense pressure to stand out from the crowd to attract mates—not only must they produce attractive signals, those signals must also be perceived clearly above the din. As signaling is a costly endeavor, it would be adaptive for males to recognize the relative attractiveness of their competitors and to adjust signaling behavior as the social environment changes. Using playback experiments, we show that male treefrogs modify call features and call timing in response to more attractive rivals. Our study also highlights that when studying chorusing species, the dual demands of producing attractive calls and placing them in attractive positions require simultaneous attention to both aspects of calling behavior. Only then is it possible to appreciate the potential trade-offs involved: males lengthening their call period when interacting with attractive rivals would appear maladaptive without the knowledge that this behavior results in reduced call overlap.

Ecological light pollution affects anuran calling season, daily calling period, and sensitivity to light in natural Brazilian wetlands.

Ecological light pollution alters an environment's light cycle, potentially affecting photoperiod-controlled behavior. Anurans, for example, generally breed nocturnally, and the influence of light pollution on their natural history may therefore be especially strong. In this study, we tested this hypothesis by measuring male calling behavior of anuran communities in natural wetlands in southern Brazil exposed or not exposed to street lights. We recorded seasonal and diel calling activity and calling response to a light pulse. The peak calling season differed between continuously lit and unlit locations with most species in illuminated wetlands shortening their calling season and calling earlier in the year. In unlit breeding sites, Boana pulchella, Pseudis minuta, and Pseudopaludicola falcipes confined their calling activity to well-defined hours of the night, but in continuously lit areas, these species called more continuously through the night. A 2-minute light pulse inhibited calling, but only in unlit wetlands. After a light pulse, frogs quickly resumed calling-suggesting acclimatization to brief artificial light exposure. Our field experiment presents a convincing example of ecological light pollution showing that artificial light alters the seasonal and diel calling time of some South American wetland anurans. It also documents their acclimatization to brief lighting when being continuously exposed to light.

Contact calling behaviour in the male ring‐tailed lemur (Lemur catta)

AbstractThe ring‐tailed lemur (Lemur catta) is a group‐living strepsirhine primate endemic to Madagascar that has a complex vocal repertoire including affiliative moan and hmm calls. Past research has suggested that both vocalisations may be contact calls, and we assessed their usage in addition to examining the effect of individual differences and social factors on male calling behaviour. We tested three hypotheses: the group cohesion, preferred companion and individual differences hypotheses. From March to July 2010, 565 h of focal animal data were collected on 31 males aged ≥1 year at the Beza Mahafaly Special Reserve, Madagascar. Focal males were observed for 30 min, with vocalisations, allogrooming and agonistic interactions noted using one‐zero sampling, and general behaviour, nearest neighbour identity and distance noted using instantaneous point sampling, all at 2.5 min intervals. We found support for the group cohesion hypothesis for both vocalisations, and support for the preferred companion and individual differences hypotheses for the hmm but not the moan vocalisation. Moan and hmm calls maintained the distance between a male and his nearest neighbour, and were made at higher rates during behaviours which may lead to separation from conspecifics, such as travel and vigilance. Males made hmm calls at higher rates when they were low‐ranking, and/or when the nearest neighbour of a male or a preferred companion of either sex. Low‐ranking males may hmm call to maintain proximity to specific individuals within social groups who will show them increased tolerance, with the hmm signalling peaceful intent. Ring‐tailed lemurs are one of the best living models of gregarious primate ancestors, and gaining a better knowledge of the function and range of usage of their contact calls informs our understanding of the evolution of primate cognition.

Cryptic female Strawberry poison frogs experience elevated predation risk when associating with an aposematic partner.

Population divergence in sexual signals may lead to speciation through prezygotic isolation. Sexual signals can change solely due to variation in the level of natural selection acting against conspicuousness. However, directional mate choice (i.e., favoring conspicuousness) across different environments may lead to gene flow between populations, thereby delaying or even preventing the evolution of reproductive barriers and speciation. In this study, we test whether natural selection through predation upon mate‐choosing females can favor corresponding changes in mate preferences. Our study system, Oophaga pumilio, is an extremely color polymorphic neotropical frog with two distinctive antipredator strategies: aposematism and crypsis. The conspicuous coloration and calling behavior of aposematic males may attract both cryptic and aposematic females, but predation may select against cryptic females choosing aposematic males. We used an experimental approach where domestic fowl were encouraged to find digitized images of cryptic frogs at different distances from aposematic partners. We found that the estimated survival time of a cryptic frog was reduced when associating with an aposematic partner. Hence, predation may act as a direct selective force on female choice, favoring evolution of color assortative mating that, in turn, may strengthen the divergence in coloration that natural selection has generated.

Disruption of reproductive behavior of grapevine cicada, Cicadatra alhageos, by acoustic signals playback

AbstractThe grapevine cicada, Cicadatra alhageos (Kolenati) (Hemiptera: Cicadidae), is a key pest of grapevine (Vitis spp., Vitaceae) in the Middle East. The main damage is caused by nymphs that feed on root sap, and adults that oviposit on branches. As males produce sound to attract females, one of the control methods can be disruption of sexual communication. Disruptive effects of acoustic playbacks on singing males were studied. Signals (0.5–10 kHz) were broadcast to disrupt male calling behavior. Playback of acoustic signals interrupted male sexual signalling. To reduce female oviposition behavior in the field, an experiment was conducted based on a completely randomized design with two treatments (control vs. acoustic broadcasting) and four replications over a period of 3 years. Playback of disruption signals in the field reduced female oviposition on grapevine branches that were close to the signal source. Therefore, application of acoustic stimuli may be an effective and low‐cost control method against grapevine cicada.

Acoustic communication in two species of the Hypsiboas albopunctatus group (Anura: Hylidae) in sympatry and allopatry

Tropical anuran communities are very diverse. Nevertheless, much of their ecological and historical processes remain unknown. Bioacoustical studies are important to help to solve these puzzles. In the present study we examined the effect of environmental (air temperature and humidity) and morphological (body size) attributes on the acoustic parameters of two frogs of the Hypsiboas albopunctatus species group (H. albopunctatus and H. paranaiba ) living in sympatry and allopatry in the Brazilian cerrado. We also investigated if the presence of one species influences the spatial distribution or vocal behaviour of the other. We found H. albopunctatus and H. paranaiba males emitting advertisement and aggressive calls in sympatry and allopatry. Although the calling behavior of H. paranaiba did not differ in sympatry and allopatry, differences were noted for H. albopunctatus . Bioacoustics is the main form of communication in anurans, and is one of the best ways to discriminate among species. Variations in the calling behavior of males and what drives these variations in both species is central to better understand the processes of specific recognition and female attraction.

Context and condition dependent plasticity in sexual signaling in gray treefrogs

For many species sexual signaling is a very costly activity, both in terms of energetic expenditure and increased conspicuousness to predators. One potential strategy to limit the costs of signaling is to only signal at maximum effort in contexts when signaling is expected to be most effective. Multiple studies have documented extensive plasticity in sexual signaling within a variety of contexts, however fewer experiments have examined individual-level variation in the extent of signaling plasticity and the causes of this variation. In this study we examined the influence of size and physical condition on the magnitude of signaling plasticity using a gray treefrog (Hyla versicolor) study system. We quantified signaling plasticity by recording male calling behavior first in the absence and then in the presence of a sexually receptive female. For one call property, call length, we found that both weight and condition had a significant influence on the magnitude of plasticity. Smaller males, and males in higher condition exhibited the greatest degree of plasticity. We discuss several possible explanations for this pattern and provide suggestions for future work to examine the consequences of this plasticity and the potential interactive effects of multiple biotic and abiotic contexts on signaling plasticity.

Male Sexual Behavior and Pheromone Emission Is Enhanced by Exposure to Guava Fruit Volatiles in Anastrepha fraterculus.

BackgroundPlant chemicals can affect reproductive strategies of tephritid fruit flies by influencing sex pheromone communication and increasing male mating competitiveness.Objective and MethodologyWe explored whether exposure of Anastrepha fraterculus males to guava fruit volatiles and to a synthetic blend of volatile compounds released by this fruit affects the sexual performance of wild and laboratory flies. By means of bioassays and pheromone collection we investigated the mechanism underlying this phenomenon.ResultsGuava volatile exposure enhanced male mating success and positively affected male calling behavior and pheromone release in laboratory and wild males. Changes in male behavior appear to be particularly important during the initial phase of the sexual activity period, when most of the mating pairs are formed. Exposure of laboratory males to a subset of guava fruit volatiles enhanced mating success, showing that the response to the fruit might be mimicked artificially.ConclusionsVolatiles of guava seem to influence male mating success through an enhancement of chemical and physical signals related to the communication between sexes. This finding has important implications for the management of this pest species through the Sterile Insect Technique. We discuss the possibility of using artificial blends to improve the sexual competitiveness of sterile males.

Effect of temporal and spectral noise features on gap detection behavior by calling green treefrogs

Communication plays a central role in the behavioral ecology of many animals, yet the background noise generated by large breeding aggregations may impair effective communication. A common behavioral strategy to ameliorate noise interference is gap detection, where signalers display primarily during lulls in the background noise. When attempting gap detection, signalers have to deal with the fact that the spacing and duration of silent gaps is often unpredictable, and that noise varies in its spectral composition and may thus vary in the degree in which it impacts communication. I conducted playback experiments to examine how male treefrogs deal with the problem that refraining from calling while waiting for a gap to appear limits a male's ability to attract females, yet producing calls during noise also interferes with effective sexual communication. I found that the temporal structure of noise (i.e., duration of noise and silent gap segments) had a stronger effect on male calling behavior than the spectral composition. Males placed calls predominantly during silent gaps and avoided call production during short, but not long, noise segments. This suggests that male treefrogs use a calling strategy that maximizes the production of calls without interference, yet allows for calling to persist if lulls in the background noise are infrequent.

Exogenous testosterone in male Downy Woodpeckers leads to reduced calling behavior of both males and their female partners during the non-breeding period

Abstract Numerous studies have shown that testosterone (T) increases singing rates of passerine birds, but much less is known about the influence of T on non-song vocalizations, particularly in non-passerine species. Woodpeckers (order Piciformes) give several non-song vocalizations in a variety of social contexts throughout the year, including whinny and pik calls. We gave free-living male Downy Woodpeckers (Picoides pubescens) subcutaneous T implants during the non-breeding period to determine whether the incidences of these calls were greater among experimental males and their female partners compared to control males and females. We also tested whether calls were given more or less often when pair members were spatially proximate, and whether T treatment affected this pattern. Both call types were more likely given when pair members were nearby (<40 m), and this was true regardless of T treatment. Surprisingly, both males with T-implants and their female partners showed significantly lower incidences ...

The antiestrogens tamoxifen and fulvestrant abolish estrogenic impacts of 17α-ethinylestradiol on male calling behavior of Xenopus laevis.

Various synthetic chemicals released to the environment can interfere with the endocrine system of vertebrates. Many of these endocrine disrupting compounds (EDCs) exhibit estrogenic activity and can interfere with sexual development and reproductive physiology. More recently, also chemicals with different modes of action (MOAs), such as antiestrogenic, androgenic and antiandrogenic EDCs, have been shown to be present in the environment. However, to date EDC-research primarily focuses on exposure to EDCs with just one MOA, while studies examining the effects of simultaneous exposure to EDCs with different MOAs are rare, although they would reflect more real, natural exposure situations. In the present study the combined effects of estrogenic and antiestrogenic EDCs were assessed by analyzing the calling behavior of short-term exposed male Xenopus laevis. The estrogenic 17α-ethinylestradiol (EE2), and the antiestrogenic EDCs tamoxifen (TAM) and fulvestrant (ICI) were used as model substances. As previously demonstrated, sole EE2 exposure (10−10 M) resulted in significant alterations of the male calling behavior, including altered temporal and spectral parameters of the advertisement calls. Sole TAM (10−7 M, 10−8 M, 10−10 M) or ICI (10−7 M) exposure, on the other hand, did not affect any of the measured parameters. If frogs were co-exposed to EE2 (10−10 M) and TAM (10−7 M) the effects of EE2 on some parameters were abolished, but co-exposure to EE2 and ICI (10−7 M) neutralized all estrogenic effects. Thus, although EDCs with antiestrogenic MOA might not exhibit any effects per se, they can alter the estrogenic effects of EE2. Our observations demonstrate that there is need to further investigate the combined effects of EDCs with various, not only opposing, MOAs as this would reflect realistic wildlife situations.

Environmental Factors Affecting Calling Behavior of Sympatric Frog Species at an Atlantic Rain Forest Area, Southeastern Brazil

The diel and seasonal calling activities of anurans are regulated by several environmental factors. We studied the effect of environmental factors on patterns of calling behavior of six sympatric frogs in an area of Atlantic rain forest at Ilha Grande, south of Rio de Janeiro state, Brazil. The number of calling males and the number of calls of each species were recorded at hourly intervals from October 1998 to September 2000. Two analyses were performed: hourly calling behavior of males of each species was related to air temperature, and monthly calling was related to air temperature and cumulative short-term rainfall. Males of Leptodactylus marmoratus, Aplastodiscus eugenioi, Physalaemus signifer, Scinax hayii, and S. trapicheiroi called mainly at night, whereas male Ischnocnema parva called mostly at dusk and dawn. The species studied at Ilha Grande rain forest called mainly in the wettest and warmest months. Scinax trapicheiroi, P. signifier, and A. eugenioi called throughout the year. Leptodactylus marmoratus was the only species whose calling behavior was restricted to a few months. Air temperature had a significant effect on the hourly number of calls for L. marmoratus, A. eugenioi, S. hayii, and S. trapicheiroi, and rainfall had a significant effect on the monthly number of calls of I. parva.

Behavioral Syndromes in the Sagebrush Cricket: A Pilot Study to Quantify Individual Variation in Male Calling Behavior

The field of behavioral ecology has recently been reinvigorated by the addition of the notion of behavioral syndromes (a.k.a. animal personality). Behavioral syndromes imply the existence of individual variation in behavioral expression that is consistent across distinct functional contexts (e.g. foraging, mating, anti-predator). The syndromes paradigm suggests that the behavioral phenotype is best viewed as an integrated phenomenon wherein any given behavior can only be fully understood by studying selection pressures in all contexts. Here we report on a pilot study on behavioral syndromes in the Sagebrush cricket (Cyphoderrris strepitans), an acoustic Orthopteran insect that inhabits high altitude sagebrush meadows of Grand Teton National Park. The results of our preliminary analysis suggest very little consistent repeatability in the mating behavior of C. strepitans. In addition, we make note of the synergistic collaboration in our group between faculty researchers and graduate, undergraduate and high school research collaborators.

Calling behaviour of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol

Event Abstract Back to Event Calling behaviour of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol Frauke Hoffmann1* and Werner Kloas1, 2 1 Leibniz Institute of Freshwater Ecology and Inland Fisheries, Department of Ecophysiology and Aquaculture, Germany 2 Humboldt University Berlin, Department of Endocrinology, Germany 17α-ethinyl estradiol (EE2), a main component of many contraceptive pills, is an environmentally relevant model substance for estrogenic endocrine disrupting compounds (EDC). In this study, effects of EE2 on male mate calling behaviour of Xenopus laevis induced by human chorionic gonadotropin treatment were investigated. Adult males were exposed to EE2 at five different concentrations (296 μg/L, 2.96 μg/L, 29.6 ng/L, 2.96 ng/L, and 0.296 ng/L) for 96 h. Effects of the treatments were analyzed by determining the total calling activity as well as the preferred utilization of different call types used in their vocalizations. Additionally, effects of EE2 exposures on temporal and spectral parameters of the advertisement calls (AC) were analyzed. While the absolute calling activity was not affected, the relative proportions of AC, calls indicating a sexually aroused state of the male, were diminished even by the lowest investigated EE2 concentration, 0.296 ng/l. The proportions of produced call types signalling a sexually unaroused state of the male, like rasping, on the other hand increased significantly in all EE2 treatment groups. EE2 exposure also altered several temporal and spectral features of the AC, per se; click durations decreased and accentuation of clicks within the calls diminished. The results of additional playback experiments examining the ecological relevance of these alterations of call features suggest that exposures to environmentally relevant concentrations of EE2 lower the chances of exposed male X. laevis to mate and reproduce successfully. In a supplemental experiment we also show that the alterations of the male advertisement call features are reversible over time. To our knowledge this study provides for the first time evidence that estrogens affect parameters of male calling behaviour of X. laevis and that calling behaviour can be used as highly sensitive non-invasive biomarker for the detection of estrogenic EDC. Acknowledgements We would like to thank the German Environmental Foundation (Deutsche Bundesstiftung Umwelt, DBU, Osnabrück, Germany) for providing a doctoral scholarship for F. H. (AZ 20008/987) Keywords: 17α-ethinyl estradiol, amphibian, calling behavior, endocrine disrupting compounds, estrogen, Xenopus laevis Conference: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology, Ann Arbor, United States, 13 Jul - 16 Jul, 2011. Presentation Type: Oral Presentation Topic: Endocrine disruption Citation: Hoffmann F and Kloas W (2011). Calling behaviour of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol. Front. Endocrinol. Conference Abstract: NASCE 2011: The inaugural meeting of the North American Society for Comparative Endocrinology. doi: 10.3389/conf.fendo.2011.04.00018 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 05 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Ms. Frauke Hoffmann, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Department of Ecophysiology and Aquaculture, Berlin, 12587, Germany, f.hoffmann@igb-berlin.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Frauke Hoffmann Werner Kloas Google Frauke Hoffmann Werner Kloas Google Scholar Frauke Hoffmann Werner Kloas PubMed Frauke Hoffmann Werner Kloas Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Calling behavior of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol

Event Abstract Back to Event Calling behavior of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol Frauke Hoffmann1* and Werner Kloas1, 2 1 Leibniz Institute of Freshwater Ecology and Inland Fisheries, Department of Ecophysiology and Aquaculture, Germany 2 Humboldt University Berlin, Department of Endocrinology, Germany 17α-ethinyl estradiol (EE2), a main component of many contraceptive pills, is an environmentally relevant model substance for estrogenic endocrine disrupting compounds (EDC). In this study, effects of EE2 on male mate calling behaviour of Xenopus laevis induced by human chorionic gonadotropin treatment were investigated. Adult males were exposed to EE2 at five different concentrations (296 μg/l, 2.96 μg/l, 29.6 ng/l, 2.96 ng/l, and 0.296 ng/) for 96 h. Effects of the treatments were analyzed by determining the total calling activity as well as the preferred utilization of different call types used in their vocalizations. Additionally, effects of EE2 exposures on temporal and spectral parameters of the advertisement calls (AC) were analyzed. While the absolute calling activity was not affected, the relative proportions of AC, calls indicating a sexually aroused state of the male, were diminished even by the lowest investigated EE2 concentration, 0.296 ng/l. The proportions of produced call types signalling a sexually unaroused state of the male, like rasping, on the other hand increased significantly in all EE2 treatment groups. EE2 exposure also altered several temporal and spectral features of the AC, per se; click durations decreased and accentuation of clicks within the calls diminished. The results of additional playback experiments examining the ecological relevance of these alterations of call features suggest that exposures to environmentally relevant concentrations of EE2 lower the chances of exposed male X. laevis to mate and reproduce successfully. In a supplemental experiment we also show that the alterations of the male advertisement call features are reversible over time. To our knowledge this study provides for the first time evidence that estrogens affect parameters of male calling behaviour of X. laevis and that calling behaviour can be used as highly sensitive non-invasive biomarker for the detection of estrogenic EDC. Acknowledgements We would like to thank the German Environmental Foundation (Deutsche Bundesstiftung Umwelt, DBU, Osnabrück, Germany) for providing a doctoral scholarship for F. H. (grant no. AZ 20008/987). Keywords: 17α-ethinyl estradiol, amphibian, calling behavior, endocrine disrupting compounds, estrogen, Xenopus laevis Conference: ISAREN 2011: 7th International Symposium on Amphibian and Reptilian Endocrinology and Neurobiology, Ann Arbor, United States, 11 Jul - 13 Jul, 2011. Presentation Type: Oral Presentation Topic: Endocrine disruption Citation: Hoffmann F and Kloas W (2011). Calling behavior of male South African clawed frogs (Xenopus laevis) is affected by 17α-ethinyl estradiol. Front. Endocrinol. Conference Abstract: ISAREN 2011: 7th International Symposium on Amphibian and Reptilian Endocrinology and Neurobiology. doi: 10.3389/conf.fendo.2011.03.00017 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 06 Jul 2011; Published Online: 09 Aug 2011. * Correspondence: Ms. Frauke Hoffmann, Leibniz Institute of Freshwater Ecology and Inland Fisheries, Department of Ecophysiology and Aquaculture, Berlin, 12587, Germany, f.hoffmann@igb-berlin.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Frauke Hoffmann Werner Kloas Google Frauke Hoffmann Werner Kloas Google Scholar Frauke Hoffmann Werner Kloas PubMed Frauke Hoffmann Werner Kloas Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.