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The article presents the results of a study of the dynamics of autumn migration of small birds obtained during their captures with mist nets in the Kurgan Oblast in 2013, 2014 and 2016. Overall, we studied 55 species and report changes in their relative abundance from late July to mid-October as well as the starting, ending and peak dates of the migration for most species. Also, we determined the sequence of their departures from the region, classified the species by the dynamics and the number of main migration waves, defined the dominant species in the captures both for the entire migration period and for its different stages. Moreover, in the article we discuss long-term changes in the timing of autumn bird migration in the forest-steppe Trans-Urals, its direction, duration of stops, timing of migration of individuals from different age and sex groups.

Across the globe, unprecedented declines have been reported across a range of taxa. Among the most well documented are declines in bird populations, with most declines attributable to human activities such as deforestation and other alterations to habitats. There is increasing evidence that bird populations also have declined at sites within large expanses of relatively undisturbed lowland tropical forest, such as in Amazonia. Causes of such declines likely are varied and may be related to direct or indirect effects of climate change. Here, we use mist-net data and direct observations to examine changes in bird numbers over a 22-yr period on two 100-ha study plots in an Amazonian lowland forest of eastern Ecuador. As previously reported, capture rates experienced large declines from 2009 on; observation rates also showed large declines through 2013 but subsequently have shown no consistent trend up or down. Overall capture rates and observation rates are now approximately half the rates during the first decade. Most foraging guilds also declined over time, with declines particularly pronounced among insectivorous groups. With few exceptions, patterns of change were similar between plots suggesting a more general response rather than responses to local factors on each plot. Capture rates and observation rates of ∼90% of the most common species in both understory and canopy were lower during the latter part of the study, with only a few species (∼10%) showing increases. Similarly, large declines were seen in both canopy and understory mixed-species flocks. Large declines in bird numbers have been noted in other tropical sites that have conducted long-term population studies, including Panama and Brazil, suggesting a response to large-scale factors, such as climate change. While not yet documented, the consequences of losing approximately 50% of population abundance are likely substantial and could result in local extinction of rare species, altered species interactions and social organization, as well as declining ecological function and biotic integrity of these tropical forest ecosystems.

We captured the Spix’s Disk-winged Bat, Thyroptera tricolor Spix, 1823, at two locations in Santa Catarina state, southern Brazil. These are the first records of occurrence of T. tricolor from the state and expand the southern limit of the species’ geographical range by 408 km. With our new data, 52 species of bat are now con-firmed to occur in Santa Catarina; this state has the second richest bat fauna in southern Brazil.

Different sampling methods are used to study bird diversity in the tropics, mist nets being one of the most common approaches. However, camera traps have been used for this purpose in the last 20 years. We compared the performance of mist nets and camera traps in sampling the diversity of understory and sub-canopy birds in a Neotropical rainforest. Given its high biodiversity, obtaining accurate bird diversity estimates in these forests is a challenging task. We sampled secondary forest patches in the Colombian central Andes between 2019 and 2021. We compared the effectiveness of both methods based on six comparison criteria (body size, foraging stratum, detection difficulty, habitat specialization, population trend, and migratory status). We recorded a total of 99 bird species: 92 species were captured using mist nets and 37 species using camera traps; 30 species were detected using both methods (mainly generalist and abundant birds). Mist net's effectiveness was 83%, while camera trap effectiveness was 68%. Differences in sampling effectiveness were mainly determined by body size, as small birds were captured using mist nets, while camera traps often recorded large birds. However, detection difficulty and habitat specialization were also relevant. Camera traps effectively recorded ground-dwelling species that were not captured in mist nets. In contrast, those birds that forage in the subcanopy stratum were mainly captured in the mist nets but not detected in camera traps. Although both methods detected different species, we found similar patterns regarding estimated species richness among different categories of body size, detection difficulty, population trend, and behavior, but not for habitat specialization. As both methods have advantages and limitations, using mist nets and camera traps together would improve bird diversity estimations. We urge investigators to explore canopy ecology with camera traps, as they provide long-term information that cannot be obtained with other methods. [ABSTRACT FROM AUTHOR]

Abstract In studies of avian diversity, many different methods have been applied. Since methodological approaches may affect research results, the choice of a given methodology must be consistent with the scientific objectives. The aim of this study was to investigate how different methodologies with their intrinsic limitations help detect and monitor birds to evaluate how they complement each other in the survey of species. Three different assessment methods, mist nets, point counts, and autonomous acoustic recordings were used to serve this purpose in a study of different Pantanal habitats, such as savannas and forests. The point counts detected more species (126 species) than the two other methods autonomous acoustic recordings (113 species) and mist nets (79 species). We observed significant differences in the number of species detected by mist nets and the other two methods. Each survey method identified exclusive species. When comparing habitats, all three methods showed significant differences in bird species composition. Savannas were richer in bird species than forests, and replacement was the main driver responsible for the differences in beta diversity between the habitats. The three methodologies, when applied together, proved to be complementary in avian species detection.

The use of mist nets is the most widespread technique to capture bats; however, no study has compared if the type of ground-level mist net used during sampling affects bat captures. We sampled bats using three different types of mist nets that varied in mesh (16, 18, and 20 mm) and denier/ply (45/1 and 75/2) sizes over 76 half-night surveys. We used 17–20 mist nets and checked them at intervals of 15–20 min. Capture rate for echolocating bats was higher in the two mist nets with the biggest denier/ply and smaller mesh sizes. "Ultrathin bat mist nets" showed the lowest capture rates (1.5 times less than "Regular bat mist nets"), whereas "Bird mist nets" had capture rates only 1.2 times smaller than "Regular bat mist nets." Our results showed that "Bird mist nets" can sample echolocating bats almost as well as "Regular bat mist nets," and that thinner mist nets may not be the best solution to capture bats that echolocate at high frequencies in this type of surveys. We highlight the importance of considering the efficiency, durability, and longevity of mist nets when choosing the ideal mist-net type for a bat survey. [ABSTRACT FROM AUTHOR]

The long-term study of bat communities often depends on a diverse set of sampling methodologies that are chosen based on the species or habitat management priorities of the research project. Integrating the data from a diverse set of methodologies (such as acoustic monitoring and mist net sampling) would improve our ability to characterize changes in community structure or composition over time, such as one would expect following an emergent infectious disease such as white-nose syndrome. We developed a Bayesian state-space model to integrate these disparate data into a common currency (relative abundance). We collected both acoustic monitoring and mist net capture data over an 8-y period (2006-2014) to document shifts in the bat community in central New England, USA, in response to the onset of white-nose syndrome in 2009. The integrated data model shows a significant decline in the abundance of little brown bat Myotis lucifugus, northern long-eared bat Myotis septentrionalis, and hoary bat Lasiurus cinereus, and an increase in abundance of the eastern small-footed bat Myotis leibii and the eastern red bat Lasiurus borealis. There was no evidence for a change in abundance in the big brown bat Eptesicus fuscus since the onset of white-nose syndrome. The consistency of this model with regional estimates of decline over the same time period support the validity of our relative abundance estimate. This model provides the opportunity to quantify shifts in other communities where multiple sampling methodologies were employed, and therefore provides natural resource managers with a robust tool to integrate existing sampling data to quantify changes in community composition that can inform conservation and management recommendations. [ABSTRACT FROM AUTHOR]

Regular nylon or polyester mist nets used for capturing bats have several drawbacks, particularly that they are inefficient at sampling insectivorous species. One possible alternative is to use monofilament nets, whose netting is made of single strands of yarn instead of several as regular nets, making them less detectable. To date, only one study has quantified the differences in capture rates between monofilament and regular mist nets for the study of bats, yet surprisingly, its findings suggest that the latter are more efficient than the former. Here, we provide further evidence of the differences in sampling efficiency between these two nets. We captured 90 individuals and 14 species in regular nets and 125 individuals and 20 species in monofilament nets. The use of monofilament nets increased overall capture rates, particularly for insectivorous species. Species accumulation curves indicate that samples based on regular nets are significantly underestimating species diversity, most notably as these nets fail at sampling rare species. We show that incorporating monofilament nets into bat studies offers an opportunity to expand records of different guilds and rare bat species and to improve our understanding of poorly known bat assemblages while using a popular, relatively cheap and portable sampling method.

Copyright of Therya is the property of Asociacion Mexicana de Mastozoologia, A. C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Atlantic Forest in the State of Paraíba integrates the Pernambuco Center of Endemism. The present work investigated understory bird communities of three of its remnants using ten mist nets installed at eight different points of the forest understory of each area. We captured 333 birds of 44 species and 19 families. Bird richness and abundance did not differ between the three remnants (KW = 6.08; p = 0.04 and KW = 10.54; p = 0.004). The composition was little similar among them, and each area presented high species diversity and evenness. The most captured species were Arremon taciturnus (n = 40), Chiroxiphia pareola (n = 32) and Conopophaga melanops (n = 28). C. melanops has a local threat status of “vulnerable” and is considered endemic. Endangered and endemic species each represented 15.91% of the captures. Both Reserva Biológica Guaribas areas had the highest number of threatened species, while Reserva Particular do Patrimônio Natural Engenho Gargaú showed the highest number of endemic and understory insectivorous species, which indicates a better quality status in comparison to the other two. These results show the importance of the remnants to bird conservation in Northeastern Brazil.

Although Rio de Janeiro is one of the best sampled states of Brazil for bats, there are still some poorly studied islands on its coast. Hence, we inventoried the bat species of an island on the southwestern coast of Rio de Janeiro, compared five sites sampled within this island, and compared its bat community with seven other sites in the same region. We carried out sampling in July 1995 and from September 2006 to August 2010, comprising 58 samplings. We captured a total of 1502 individuals of 25 bat species with mist nets set far from roosts, or close to or inside roosts. The most abundant species wereArtibeus lituratus, Molossus molossus, andCarollia perspicillata. Total sampling effort was 89,400 m2 h. The present study was one out of five inventories carried out in the southwestern coast of Rio de Janeiro that registered more than 1000 bat individuals from more than 24 bat species. Long-term inventories on islands are still needed, because they can result in a large number of species and captures as observed in the present study. [ABSTRACT FROM AUTHOR]

The combined use of different methods for surveying bat assemblages has increased over the last few decades. The objective of this study was to assess the efficiency of bat inventories by comparing assemblages parameters (species richness, abundance and composition) using the 3 most conventional capture methods (ground-level and sub-canopy mist nets and harp traps), in a lowland tropical dry forest in Yucatán, Mexico. In ground mist nets, only phyllostomid species were recorded, principally frugivorous and nectarivorous species, while in harp traps the majority were insectivorous species from other families. Our results indicate that for the order Chiroptera the most efficient combination of capture methods is the simultaneous use of ground mist nets and harp traps. However, an inventory of Phyllostomidae is reliably achieved with only ground mist nets. Also, a combination of ground and sub-canopy mist nets does not provide an efficient sampling strategy.El uso combinado de diferentes métodos de muestreo de ensambles de murciélagos se ha incrementado en las últimas décadas. El objetivo de este estudio fue evaluar la eficiencia de los inventarios de murciélagos comparando los parámetros del ensamble (riqueza de especies, abundancia y composición) usando los 3 métodos de captura convencionales (redes de niebla a nivel de sotobosque y sub-dosel, y trampas arpa), en una selva baja caducifolia de Yucatán, México. En las redes de sotobosque se registraron solamente especies de filostómidos, principalmente especies frugívoras y nectarívoras; mientras que en las trampas arpa, la mayoría fueron especies insectívoras de otras familias. Nuestros resultados indican que para el orden Chiroptera la combinación más eficiente de métodos de captura es el uso simultáneo de redes de sotobosque y trampas arpa. Sin embargo, se alcanza un inventario confiable de filostómidos sólo con las redes de sotobosque. Además, una combinación de redes de sotobosque y sub-dosel no provee una eficiente estrategia de muestreo.

Mammal diversity assessments based on DNA derived from invertebrates have been suggested as alternatives to assessments based on traditional methods; however, no study has field-tested both approaches simultaneously. In Peninsular Malaysia, we calibrated the performance of mammal DNA derived from blowflies (Diptera: Calliphoridae) against traditional methods used to detect species. We first compared five methods (cage trapping, mist netting, hair trapping, scat collection, and blowfly-derived DNA) in a forest reserve with no recent reports of megafauna. Blowfly-derived DNA and mist netting detected the joint highest number of species ( n = 6). Only one species was detected by multiple methods. Compared to the other methods, blowfly-derived DNA detected both volant and non-volant species. In another forest reserve, rich in megafauna, we calibrated blowfly-derived DNA against camera traps. Blowfly-derived DNA detected more species ( n = 11) than camera traps ( n = 9), with only one species detected by both methods. The rarefaction curve indicated that blowfly-derived DNA would continue to detect more species with greater sampling effort. With further calibration, blowfly-derived DNA may join the list of traditional field methods. Areas for further investigation include blowfly feeding and dispersal biology, primer biases, and the assembly of a comprehensive and taxonomically-consistent DNA barcode reference library. [ABSTRACT FROM AUTHOR]

Copyright of Genome is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Uluguru Mountains form a component block of the Eastern Arc Mountains of Tanzania and Kenya and are known for a high degree of endemic vertebrate and plant taxa. Among the Eastern Arc Mountains, the Uluguru Mountains rank second in the number of endemic species. Although the forests in these mountains have received considerable ornithological attention, studies on how forest bird communities in the available low elevation forests are affected by seasons remain patchy and sporadic. Such studies are important because in the Uluguru Mountains, forest destruction in the lower slopes has been severe to an extent that there is very little substantial forest survives below 900 m above sea level. Using mist netting, seasonal variation in understorey bird communities in the remaining low elevation forests in the Uluguru Nature Reserve was assessed between 2005 and 2011. Species diversity and relative abundance of the birds were higher during the cold season in comparison with the hot season possibly due to seasonal elevational movements of some species. Elevational migrants made a large proportion of the avifauna in the study area. The results suggest that low altitude forests are important cold season refugia of elevational migrants and these forests need continual protection. [ABSTRACT FROM AUTHOR]

Mist-nets alternating 36-mm and 61-mm mesh in woods and low vegetation of "cerrado" (Brazilian savanna) tested bird-capture efficiency relative to bird length and mass. Of 1,296 birds captured and 102 species, 785 (93 species) were with 36-m mesh and 511 (69 species) with 61-mm mesh. The 61-mm mesh improved capture rates only for some larger species; so, in general, 36-mm mesh mist-nets are more appropriate for field work in "cerrado" areas.

Fire is one of the main threats facing the long-term survival of the forests in the Eastern Arc Mountains. Yet, our understanding of how it affects fauna, particularly birds, is still poor. A fire that originated on surrounding farmland burned approximately half of Kimboza Forest Reserve between 13 and 15 October 2010. To better understand how birds respond to fire, a short-term study of understorey bird diversity and abundance in this forest reserve was conducted by comparing burned and unburned sites twenty months post-fire. Capture rates were significantly higher at the unburned site compared to the burned site. Bird species diversity was also higher at the unburned site than at the burned site. Despite the brevity of the study, the results suggest that fire has negative effects on forest avifauna and forest fires need to be prevented at Kimboza Forest Reserve as they affect the distribution and diversity of understorey birds. [ABSTRACT FROM AUTHOR]

For birds, we tested the efficacy of a technique used to obtain faecal samples and their seed content from bats by placing plastic sheets below mist nets. This method was compared with that of collecting faecal samples using cotton bags. Plastic sheets were placed below each of eight mist nets to obtain faecal samples from birds caught in cloud forest remnants. Each bird was then placed separately in a cotton bag to catch any other seeds excreted. There were 84 faecal samples in total: 64 with no seeds and 20 with seeds; of the latter 65% were obtained from the plastic sheets. A total of 407 seeds were collected, 317 from 11 plant species were collected on the plastic sheets and 90 belonging to six plant species in the bags. Seed richness and abundance were significantly greater for samples obtained using the plastic sheets than with the cotton bags. Although the number of bird faecal samples obtained did not differ between methods (13 vs 7), with the plastic sheets the number of faecal samples with seeds increased. Thus, to obtain more representative faecal samples from frugivorous birds, we strongly recommend the use of plastic sheets as part of the technique. [ABSTRACT FROM PUBLISHER]

The article presents a study on the impact of the use of different sampling techniques on maximum entropy species distribution modeling (SDM) for bats. The study involved sampling for bat presence in North Dakota via mist netting and ultrasonic acoustic monitoring. It used maximum-entropy modeling to develop habitat suitability maps for each study species. It finds that acoustic detection results in better SDMs for Myotis spp. while physical capture was best for modeling Eptesicus fuscus.

Copyright of Zeledonia is the property of Asociacion Ornitologica de Costa Rica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents the study on the construction of the over-water mist net support system which would allow bat researchers to survey over inaccessible water sources in North Dakota. It states that after the field test of a prototype, a full model was built of metal which includes mist net support arm, anchor support, and hinged gate-like mechanism for the swinging operation of the support arm. It cites that the device was built so it can easily be assembled and dismantled without using tools other than rubber mallet or post driver. It also mentions that the system have caught 5 types of bat species from North Dakota.

Seasonal capture rates of insectivorous subtropical and tropical Australian northern long-eared bats (Nyctophilus bifax) (Chiroptera: Vespertilionidae) in relation to ambient temperature and insect abundance were examined. Insect abundance varied seasonally in a subtropical region and also between subtropical and tropical habitats during winter, and decreased as nightly ambient temperature decreased. While capture rates of N. bifax were not affected by ambient temperatures and insect abundance, most captures occurred within one hour after sunset, which is generally the time of highest activity levels in microbats. Methods of care of N. bifax in captivity are also reported. N. bifax adapted well to short-term captivity (up to 14 days) and readily accepted mealworms as a food source. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article focuses on a study which involved the patterns in the movement, captures and phenology of Sharp-shinned Hawks (Accipiter striatus) in Central Coastal California. A group of researchers captured 452 Sharp-shinned Hawks at the Palomarin Field Station in the Point Reyes National Seashore located in Marin County in central coast California. The hawks were captured during every month of the year, with peak captures from late September to mid-November. The researchers reported significant increase in the capture rate which is believed to be consistent with the result of other monitoring programs.

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

From 1999 to 2005, we sampled the bat fauna of Catalonia (northeastern Spain, Mediterranean region) using 3 methods (bat detectors, mist nets, and roost surveys) and determined the total number of bat species present (S = 22). Twelve bat species and 5 acoustic groups (≥5 different species) were identified using bat detectors, 17 species were found during roost inspections, and 13 species were trapped using mist nets. However, mist nets yielded the highest species richness per number of individuals sampled, as demonstrated by rarefaction. Some species were always either over- or undersampled according to the sampling method used. We also evaluated 3 guilds of bats defined by summer roost preferences, documenting a significant correlation between guild and detection method; cavity-roosting bats were underrepresented when only bat detectors and mist-net surveys were used, whereas rock crevices or man-made structure and tree guilds were underrepresented when only roosts were surveyed. Different techniques should be used to assess the richness of bat communities and we recommend combining all the methods described above in future bat surveys. [ABSTRACT FROM AUTHOR]

Mist-nets alternating 36-mm and 61-mm mesh in woods and low vegetation of "cerrado" (Brazilian savanna) tested bird-capture efficiency relative to bird length and mass. Of 1,296 birds captured and 102 species, 785 (93 species) were with 36-m mesh and 511 (69 species) with 61-mm mesh. The 61-mm mesh improved capture rates only for some larger species; so, in general, 36-mm mesh mist-nets are more appropriate for field work in "cerrado" areas.

Abstract: South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on‐line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeographic sub‐regions. Considering the three main quantitative methods (mist net, point count, and line transect), we compiled abundance data for 745 species in 576 communities. In the data set, the most frequent species were Basileuterus culicivorus, Cyclaris gujanensis, and Conophaga lineata. There were 71 singletons, such as Lipaugus conditus and Calyptura cristata. We suggest that this small number of records reinforces the critical situation of these taxa in the Atlantic Forest. The information provided in this data set can be used for macroecological studies and to foster conservation strategies in this biodiversity hotspot. No copyright restrictions are associated with the data set. Please cite this Data Paper if data are used in publications and teaching events. [ABSTRACT FROM AUTHOR]

Bats are the second most diverse mammal order and they provide vital ecosystem functions (e.g., pollination, seed dispersal, and nutrient flux in caves) and services (e.g., crop pest suppression). Bats are also important vectors of infectious diseases, harboring more than 100 different virus types. In the present study, we compiled information on bat communities from the Atlantic Forests of South America, a species-rich biome that is highly threatened by habitat loss and fragmentation. The ATLANTIC BATS data set comprises 135 quantitative studies carried out in 205 sites, which cover most vegetation types of the tropical and subtropical Atlantic Forest: dense ombrophilous forest, mixed ombrophilous forest, semideciduous forest, deciduous forest, savanna, steppe, and open ombrophilous forest. The data set includes information on more than 90,000 captures of 98 bat species of eight families. Species richness averaged 12.1 per site, with a median value of 10 species (ranging from 1 to 53 species). Six species occurred in more than 50% of the communities: Artibeus lituratus, Carollia perspicillata, Sturnira lilium, Artibeus fimbriatus, Glossophaga soricina, and Platyrrhinus lineatus. The number of captures divided by sampling effort, a proxy for abundance, varied from 0.000001 to 0.77 individuals·h−1·m−2 (0.04 ± 0.007 individuals·h−1·m−2). Our data set reveals a hyper-dominance of eight species that together that comprise 80% of all captures: Platyrrhinus lineatus (2.3%), Molossus molossus (2.8%), Artibeus obscurus (3.4%), Artibeus planirostris (5.2%), Artibeus fimbriatus (7%), Sturnira lilium (14.5%), Carollia perspicillata (15.6%), and Artibeus lituratus (29.2%). [ABSTRACT FROM AUTHOR]