Welcome to the (urban) jungle: notes on new science, biological evolution in cities

The city – a modern jungle, where not cellulose and photosynthesis but concrete and combustion reign supreme. The question now being asked by urban planners, governments, and scientists is if it may stay like that and if it can stay like that or if it has to stay like that. Social, economic, cultural, historical, and legal factors are determinants in the ecology of urban ecosystems. Even well-managed cities are usually hostile toward non-human inhabitants. Furthermore, as with any complex system, the equilibrium is fragile, even if it exists. This publication outlines the co-evolution and ecology of humans and other species in the cities, their importance, and perspectives

The potential for acoustic individual identification in mammals

Many studies have revealed that animal vocalizations, including those from mammals, are individually distinctive. Therefore, acoustic identification of individuals (AIID) has been repeatedly suggested as a non-invasive and labor efficient alternative to mark-recapture identification methods. We present a pipeline of steps for successful AIID in a given species. By conducting such work, we will also improve our understanding of identity signals in general. Strong and stable acoustic signatures are necessary for successful AIID. We reviewed studies of individual variation in mammalian vocalizations as well as pilot studies using acoustic identification to census mammals and birds. We found the greatest potential for AIID (characterized by strong and stable acoustic signatures) was in Cetacea and Primates (including humans). In species with weaker acoustic signatures, AIID could still be a valuable tool once its limitations are fully acknowledged. A major obstacle for widespread utilization of AIID is the absence of tools integrating all AIID subtasks within a single package. Automation of AIID could be achieved with the use of advanced machine learning techniques inspired by those used in human speaker recognition or tailored to specific challenges of animal AIID. Unfortunately, further progress in this area is currently hindered by the lack of appropriate publicly available datasets. However, we believe that after overcoming the issues outlined above, AIID can quickly become a widespread and valuable tool in field research and conservation of mammals and other animals

Phylogeographic structure without pre-mating barriers: Do habitat fragmentation and low mobility preserve song and chorus diversity in a European bushcricket?

International audienc

Vocal behaviour of mates at the nest in the White-throated Dipper Cinclus cinclus: contexts and structure of vocal interactions, pair-specific acoustic signature

International audienc

The potential for acoustic individual identification in mammals

Many studies have revealed that animal vocalizations, including those from mammals, are individually distinctive. Therefore, acoustic identification of individuals (AIID) has been repeatedly suggested as a non-invasive and labor efficient alternative to mark-recapture identification methods. We present a pipeline of steps for successful AIID in a given species. By conducting such work, we will also improve our understanding of identity signals in general. Strong and stable acoustic signatures are necessary for successful AIID. We reviewed studies of individual variation in mammalian vocalizations as well as pilot studies using acoustic identification to census mammals and birds. We found the greatest potential for AIID (characterized by strong and stable acoustic signatures) was in Cetacea and Primates (including humans). In species with weaker acoustic signatures, AIID could still be a valuable tool once its limitations are fully acknowledged. A major obstacle for widespread utilization of AIID is the absence of tools integrating all AIID subtasks within a single package. Automation of AIID could be achieved with the use of advanced machine learning techniques inspired by those used in human speaker recognition or tailored to specific challenges of animal AIID. Unfortunately, further progress in this area is currently hindered by the lack of appropriate publicly available datasets. However, we believe that after overcoming the issues outlined above, AIID can quickly become a widespread and valuable tool in field research and conservation of mammals and other animals

Species Composition of Parasitic Mites of the Subfamily Picobiinae (Acariformes: Syringophilidae) Associated with African Barbets (Piciformes: Lybiidae)

In this study, we conducted a parasitological investigation of the quill mite fauna of the subfamily Picobiinae (Acariformes: Prostigmata: Syringophilidae) associated with African barbets (Aves: Piciformes: Lybiidae). We examined twenty-seven host species, representing 57% of the forty-seven known host species in the family Lybiidae, belonging to seven genera (70% of the ten genera in the family). Our research revealed that ten host species were infested by three species of picobiine mites belonging to the genus Tanopicobia: (1) Tanopicobia hallae Sikora and Skoracki, sp. n., from three species of the genus Lybius and two species of the genus Tricholaema, (2) Tanopicobia stactolaema Sikora and Skoracki, sp. n., from two species of the genus Stactolaema, and (3) Tanopicobia trachyphoni Skoracki et al., 2020, collected from three host species of the genus Trachyphonus. Our findings demonstrate that birds belonging to the family Lybiidae have a specific parasite fauna consisting exclusively of mites of the genus Tanopicobia; this mite genus is apparently restricted to African barbets

Elevated natural environmental noise impacts breeding success and vocal communication in a songbird

International audienceElevated noise is likely to participate in species decline in urban areas. By disrupting vocal communication, it may be a major factor explaining impaired reproductive success of birds. However factors impacting reproductive success are diverse in urban areas and conclusions are hard to draw. To better understand the relationships between noise, reproductive success and vocal communication, we lack investigations on bird species that evolved under constraining natural environmental noise. White-throated dippers, Cinclus cinclus, invariably nest over fast flowing water. Water stream noise can reach high sound pressure levels and exhibit a typical pink noise likely to constraint vocal signals. By monitoring a wild population, we first showed that pairs raised less fledglings in loud nest sites than in quieter areas. Secondly, we measured the impact of noise levels on vocal signals produced at the nest by using both a correlative approach (between-nest design) and an experimental approach amplifying the local environmental noise at the nest with a playback (within-nest design). Dippers vocalize at frequencies that do not overlap with the frequency range of the noise and the frequency composition of vocalizations did not change in response to the playback; suggesting that water stream noise has favoured the evolution of high frequency signals. Pairs breeding in louder sites vocalized at higher amplitude and increased the amplitude of their vocalizations in response to the playback; providing strong evidence of a Lombard effect. Pairs breeding in louder nest sites produced more pure tones-like vocalizations and showed vocal flexibility in response to the playback, using notes with a sharper and narrowed frequency spectrum. Our results show that low reproductive success in high environmental noise level may be explained by constraints on vocal communication

Adaptations des communications acoustiquesau bruit environnemental et succèsreproducteur chez le cincle plongeur Cincluscinclus.

International audienceLe bruit est une contrainte majeure sur la communication acoustique et représente un bon candidat pour expliquer le déclin des passereaux en milieu urbain. Cependant, le milieu urbain implique aussi de multiples autres contraintes et extraire les effets imposés par le bruit des autres effets reste difficile. Ainsi, l’étude d’espèces ayant évolués dans un bruit de fond naturellement fort et contraignant est cruciale pour comprendre les relations entre bruit, communication acoustique et succès reproducteur. Le cincle plongeur Cinclus cinclus est inféodé aux rivières et niche systématiquement au dessus de l’eau. Les couples subissent donc un bruit de fond continu (de 45 à 80 dB) et communiquent au nid dans cet environnement contraignant. Nous avons exploré les effets du bruit environnemental sur la structure des vocalisations émises (1) de manière corrélative (comparaison inter-couple) et (2) après une amplification expérimentale du bruit au nid (comparaison intra-couple). Nous montrons que, si les cincles produisent des vocalisations dont les propriétés spectrales se superposent peu à celles du bruit de rivière, ils expriment tout de même de la flexibilité en réponse au traitement. Les couples nichant dans les zones les plus bruyantes produisent des vocalisations de plus fortes amplitudes et sont aussi capables d’augmenter celle-ci en réponse au traitement (effet Lombard). Nous montrons enfin que les couples nichant dans les sites les plus bruyants ont plus de probabilité d’échouer leur reproduction et élèvent moins de jeunes. Ainsi, même chez une espèce évoluant dans un bruit de fond continu, ce dernier a des effets majeurs sur la communication et peut expliquer une diminution du succès reproducteur

Acoustic monitoring of rock ptarmigan: A multi-year comparison with point-count protocol

International audienceThe cost-effectiveness and reduced human effort employed in setting up acoustic monitoring in the field makes bioacoustics an appealing option for wildlife monitoring. This is especially true for secretive vocal species living in remote places. However, acoustic monitoring still raises questions regarding its reliability when compared to other, human-driven methods. In this study we compare different approaches to count rock ptarmigan males, an alpine bird species which lives at high altitudes. The monitoring of rock ptarmigan populations is traditionally conducted using a point-count protocol, with human observers counting singing males from a set of different points. We assessed the (1) feasibility and (2) reliability of an alternative counting method based on acoustic recordings followed by signal analysis and a dedicated statistical approach to estimate the abundance of males. We then (3) compared the results obtained with this bioacoustics monitoring method with those obtained through the point-count protocol approach over three consecutive years. Acoustic analysis demonstrated that rock ptarmigan vocalizations exhibit an individual stereotypy that can be used to estimate the abundance of males. Simulations, using subsets of our recording dataset, demonstrated that the clustering methods used to discriminate between males based on their vocalizations are sensitive to both the number of recorded signals, as well as the number of individuals to be discriminated. Despite these limitations, we highlight the reliability of the bioacoustics approach, showing that it avoids both observer bias and double counting, contrary to the pointcount protocol where this may occur and impair the data reliability. Overall, our study suggests that bioacoustics monitoring should be used in addition to traditional counting methods to obtain a more accurate estimate of rock ptarmigan abundance within Alpine environments