Trends in High Nature Value farmland studies: A systematic review

Background. Since the High Nature Value (HNV) concept was defined in the early 1990s, several studies on HNV farmland has been increasing over the past 30 years in Europe, highlighting the interest by scientific community of HNV farming systems supporting biodiversity conservation. The aim of this study was to evaluate the trends and main gaps on HNV farmland peer-reviewed publications in order to contribute to the effectiveness of future research in this field. Methods. Searches were conducted using the databases Web of SciencesTM and Scopus in order to identify only peer-reviewed articles on HNV farmland, published prior to July 2017. The inclusion and exclusion criteria were developed a priori. Data as year, country, type of document, subject area, taxa studied and biodiversity metrics assessed were extracted and explored in order to analyse the spatial and temporal distribution of the concept, including the main topics addressed in HNV farmland literature. Results. After screening 308 original articles, 90 were selected for this review. HNV farmland studies involved several disciplines, mainly biodiversity and conservation and environmental sciences and ecology. Most peer-reviewed articles focused on HNV farming were conducted in Spain, Italy, Ireland and Portugal. The main studied taxa were plants and birds. Taxonomic diversity was the biodiversity metric more often used to assess the biodiversity status on HNV farmland areas. A positive correlation was found between HNV farmland area and HNV farmland studies conducted in respective countries. Discussion. The HNV farmland research subject is a relative novel approach, and this systematic review provides a comprehensive overview about the main topics in the HNV farmland peer-reviewed literature contributing to highlight the main gaps and provide some considerations in order to assist the performance of HNV farming systems and conservation policies, addressed to sustain high levels of biodiversity

Number of syllables in cuckoo Cuculus canorus calls: A test using a citizen science project

International audienceRecent studies revealed that the call of the common cuckoo Cuculus canorus has more inter-individual than intra-individual variation and that the number of syllables depends on environmental conditions, but also the presence of male and female conspecifics. However, still very little is known about how song varies at a global scale, especially considering the wide distribution of this species across most of Europe and Asia. Xeno-canto.org is a vocalization repository for birdsong. We used xeno-canto.org as a data source for investigating the variables that affect the number of syllables in cuckoo calls at a large spatial scale. At a very broad geographical scale, the number of syllables in cuckoo calls predicted bird species richness. Additionally, female calls were associated with shorter males calls, and there was a positive correlation between the interaction between female calls and the number of host races parasitized by the cuckoo. These findings confirm that intraspecific and interspecific interactions significantly affect the number of syllables in cuckoo calls, and both environmental variables and biotic interactions should be considered in future studies of vocalizations in cuckoos. Last but not least, we demonstrated that a citizen science project is a useful source for ecological studies at large spatial scales

Efficient dive in shallow waters : diving behavior and feeding pattern of the Rock Shag, Phalacrocorax magellanicus, at two Patagonian colonies

Entre 1996 y 1998 se estudió, por medio de técnicas de radiotelemetría, el comportamiento de buceo y alimentación del Cormorán Cuello Negro (Phalacrocorax magellanicus) en Punta Loma y en Isla Vernacci, dos colonias de reproducción de la costa patagónica. En ambas colonias, los cormoranes bucearon por períodos prolongados (47.50 s) seguidos por breves intervalos de recuperación en superficie (14.18 s) y presentaron eficiencias de buceo altas (3.2.3.8, tiempo de buceo/tiempo en superficie). Tanto en Punta Loma como en Isla Vernacci, las aves permanecieron en el mar casi un tercio del total de horas luz (31.35%), bucearon la mayor parte del tiempo que estuvieron fuera de la colonia (aprox. 90%), realizaron numerosos viajes de alimentación diarios (2.6.3.7 viajes/día), de duración prolongada (1.7.2.6 h) y desarrollaron un elevado número de buceos por viaje (78.138). Estos resultados sugieren un alto esfuerzo de alimentación (tiempo dedicado al buceo por viaje) para cubrir los requerimientos energéticos propios y alimentar a los pichones. Una reducida disponibilidad de alimento (distribución, abundancia y accesibilidad) y el bajo rendimiento energético de las presas consumidas podrían ser algunos de los factores responsables del alto esfuerzo de alimentación sugerido.By means of radio-telemetry techniques, we study the diving behavior and feeding performance of adult Rock shags (Phalacrocorax magellanicus) from Punta Loma and Isla Vernacci, two colonies of the Patagonian coast, Argentina. In both colonies, Rock shags dived continuously (without diving bouts) during foraging trips (mean dive duration: 47-50 s, mean subsequent surface interval: 14-18 s) and showed high dive efficiencies (3.2.3.8, dive time/recovery time). Tracked birds from the two colonies spent 3135% of daylight hours at sea, diving (including dive and recovery times) for 92% of the foraging trip. They undertook many (2.6.3.7 trips/day) and prolonged (1.7.2.6 h) trips per day, and made a high number of dives per foraging trip (78.138). These results suggest a high foraging effort (diving time per foraging trip) for Rock shags from the two studied colonies, necessary to reach the daily food requirements. This high foraging effort could be associated with low prey abundance, the existence of a patchy and/or low quality food resource (in energetic terms), or both

The common cuckoo is an effective indicator of high bird species richness in Asia and Europe

AbstractCommon cuckoo Cuculus canorus is a charismatic bird species with a dominant presence in human culture: from folklore legends to nowadays there is evidence of cuckoos being a prime candidate as a surrogate of bird diversity. Recent studies demonstrated that the cuckoo can predict hotspots of taxonomic diversity and functional diversity of bird communities in European countries. In this study, we demonstrated that the cuckoo is an excellent bioindicator at multi-spatial scale, extending cuckoo surrogacy from Europe to Asia. Even using three different survey methods (transect, square, point counts), comparing the new findings with results of our research in Europe, sites where the cuckoo is present were characterized by greater species richness, while the cuckoo was absent from sites with low species richness. The goodness of fit of models based on point counts ranged between 71 and 92%. Furthermore, the cuckoo population trend mirrors the average population trend and climate suitability of overall bird communities in Europe. The common cuckoo is therefore a suitable intercontinental bioindicator of hotspots of bird richness, even under climate change scenarios or in areas where the species co-occurs with other cuckoo species, opening a new avenue for standardized citizen science on bird biodiversity surveys worldwide.</jats:p

Birds’ escape strategies in urban environments

Para huir de depredadores, las aves urbanas pueden elegir entre dos estrategias de escape: correr o volar. Estos comportamientos de huida presentan distintos costos para el individuo, teniendo el primero un menor gasto energético pero mayor riesgo de depredación y viceversa. Sin embargo, los factores que afectan la selección de una u otra estrategia han sido poco estudiados. Por lo tanto, el objetivo del estudio es analizar la variación de las diferentes estrategias de escape en aves en relación a factores intrínsecos (especie) o extrínsecos (variables ambientales, estación del año). Para esto, se investigaron los factores que influencian el comportamiento de huida de 433 individuos pertenecientes a 24 especies de aves urbanas. Se realizaron modelos lineales generalizados para determinar el efecto de los diferentes factores: cobertura vegetal e infraestructura, disturbios humanos, especie, estacionalidad, gregarismo, hábitat y tamaño del ave. La estrategia de vuelo fue preferentemente elegida durante la época reproductiva y cuando las aves formaban bandadas de mayor tamaño. A su vez, la probabilidad de seleccionar una u otra estrategia varió entre especies. Los resultados sugieren que el comportamiento de escape se ve influenciado por factores tanto intrínsecos como extrínsecos, y resaltan la capacidad de las aves para adaptar su comportamiento a las condiciones ambientales cambiantes.When escaping from predators, urban birds may choose between two strategies: to run or to fly. These escape behaviors have different costs for the individual, the first having a lower energy expenditure but a higher risk of predation and vice versa. However, little is known about the factors affecting the selection of these strategies. Therefore, this study aims to analyze the variation of different escape strategies in birds in relation to intrinsic (species) or extrinsic (environmental variables, season of the year) factors. To this end, factors that influence the flight behavior of 433 individuals belonging to 24 species of urban birds were analyzed. Generalized linear models were performed to determine the effect of the different factors: vegetation cover and infrastructure, human disturbances, species, seasonality, gregariousness, habitat, and bird size. The flight strategy was preferred during the breeding season and when birds formed larger flocks. Also, the probability of selecting one strategy or the other varied between species. The results suggest that escape behavior is influenced by both intrinsic and extrinsic factors, and highlights birds’ ability to adapt their behavior to changing environmental conditions.Fil: Bocelli, Mariana Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; ArgentinaFil: Morelli, Federico Daniel. Czech University Of Life Sciences Prague; República ChecaFil: Benedetti, Yanina. Czech University Of Life Sciences Prague; República ChecaFil: Leveau, Lucas Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentin

Flight initiation distance and refuge in urban birds

Risk-taking in birds is often measured as the flight initiation distance (FID), the distance at which individuals take flight when approached by a potential predator (typically a human). The ecological factors that affect avian FID have received great attention over the past decades and meta-analyses and comparative analyses have shown that FID is correlated with body mass, flock size, starting distance of the approaching human, density of potential predators, as well as varying along rural to urban gradients. However, surprisingly, only few studies (mainly on reptiles and mammals) have explored effects of different types of refugia and their availability on animal escape decisions. We used Bayesian regression models (controlling for the phylogenetic relatedness of bird species) to explore changes in escape behaviour recorded in European cities in relationship to the birds' distance to the nearest refuge and distance fled to the refuge. In our analyses, we also included information on the type of refuge, built-up and vegetation cover, starting distance, flock size, urbanization level, and type of urban habitat. We found that birds preferred tree refuges over artificial and bush refuges. Birds escaped earlier if the distance to the nearest refuge of any type was longer and if birds fled longer distances to the refuge. FID was shorter when birds used bushes as refugia or landed on the ground after flushing compared to using artificial refugia. Similarly, the distance fled to a refuge was shortest when using bushes, and increased when escaping to artificial substrates and trees. Birds were more timid in suburban than core areas of cities, cemeteries than parks, and in areas with higher bush cover but lower cover of built-up areas and trees. Our findings provide novel information regarding the importance of refuge proximity and type as factors affecting the escape behaviour of urban birds.MD was funded by MCIN/AEI/10.13039/501100011033 to the project URBILAND (PID2019-107423GA-I00).Peer reviewe

Urban birds tolerance towards humans was largely unaffected by COVID-19 shutdown-induced variation in human presence.

The coronavirus disease 2019 (COVID-19) pandemic and respective shutdowns dramatically altered human activities, potentially changing human pressures on urban-dwelling animals. Here, we use such COVID-19-induced variation in human presence to evaluate, across multiple temporal scales, how urban birds from five countries changed their tolerance towards humans, measured as escape distance. We collected 6369 escape responses for 147 species and found that human numbers in parks at a given hour, day, week or year (before and during shutdowns) had a little effect on birds escape distances. All effects centered around zero, except for the actual human numbers during escape trial (hourly scale) that correlated negatively, albeit weakly, with escape distance. The results were similar across countries and most species. Our results highlight the resilience of birds to changes in human numbers on multiple temporal scales, the complexities of linking animal fear responses to human behavior, and the challenge of quantifying both simultaneously in situ

Dense city centers support less evolutionary unique bird communities than sparser urban areas

Urbanization alters avian communities, generally lowering the number of species and contemporaneously increasing their functional relatedness, leading to biotic homogenization. Urbanization can also negatively affect the phylogenetic diversity of species assemblages, potentially decreasing their evolutionary distinctiveness. We compare species assemblages in a gradient of building density in seventeen European cities to test whether the evolutionary distinctiveness of communities is shaped by the degree of urbanization. We found a significant decline in the evolutionary uniqueness of avian communities in highly dense urban areas, compared to low and medium-dense areas. Overall, communities from dense city centers supported one million years of evolutionary history less than communities from low-dense urban areas. Such evolutionary homogenization was due to a filtering process of the most evolutionarily unique birds. Metrics related to evolutionary uniqueness have to play a role when assessing the effects of urbanization and can be used to identify local conservation priorities.</p

Effects of light and noise pollution on avian communities of European cities are correlated with the species’ diet

Urbanization affects avian community composition in European cities, increasing biotic homogenization. Anthropic pollution (such as light at night and noise) is among the most important drivers shaping bird use in urban areas, where bird species are mainly attracted by urban greenery. In this study, we collected data on 127 breeding bird species at 1349 point counts distributed along a gradient of urbanization in fourteen different European cities. The main aim was to explore the effects of anthropic pollution and city characteristics, on shaping the avian communities, regarding species’ diet composition. The green cover of urban areas increased the number of insectivorous and omnivorous bird species, while slightly decreasing the overall diet heterogeneity of the avian communities. The green heterogeneity—a measure of evenness considering the relative coverage of grass, shrubs and trees—was positively correlated with the richness of granivorous, insectivorous, and omnivorous species, increasing the level of diet heterogeneity in the assemblages. Additionally, the effects of light pollution on avian communities were associated with the species' diet. Overall, light pollution negatively affected insectivorous and omnivorous bird species while not affecting granivorous species. The noise pollution, in contrast, was not significantly associated with changes in species assemblages. Our results offer some tips to urban planners, managers, and ecologists, in the challenge of producing more eco-friendly cities for the future.F.M., Y.B., J.P., D.M., and J.R. were fnancially supported by the Czech Science Foundation GAČR (Project Number 18-16738S). JIA and MD were funded by the Spanish Ministry of Science and Innovation (PID2019-107423GA-I00/SRA State Research Agency/10.13039/501100011033). Poland funded PT through NCN/2016/22/Z/NZ8/00004.Peer reviewe