Ringed Research Articles

A Unified Approach to Spatial Proximity Query Processing in Dynamic Spatial Networks.

Nearest neighbor (NN) and range (RN) queries are basic query types in spatial databases. In this study, we refer to collections of NN and RN queries as spatial proximity (SP) queries. At peak times, location-based services (LBS) need to quickly process SP queries that arrive simultaneously. Timely processing can be achieved by increasing the number of LBS servers; however, this also increases service costs. Existing solutions evaluate SP queries sequentially; thus, such solutions involve unnecessary distance calculations. This study proposes a unified batch algorithm (UBA) that can effectively process SP queries in dynamic spatial networks. With the proposed UBA, the distance between two points is indicated by the travel time on the shortest path connecting them. The shortest travel time changes frequently depending on traffic conditions. The goal of the proposed UBA is to avoid unnecessary distance calculations for nearby SP queries. Thus, the UBA clusters nearby SP queries and exploits shared distance calculations for query clusters. Extensive evaluations using real-world roadmaps demonstrated the superiority and scalability of UBA compared with state-of-the-art sequential solutions.

Which birds participate in mass concentrations of Bramblings Fringilla montifringilla?\u2014Ring recoveries, biometry, age and sex composition

The Brambling Fringilla montifringilla combines several special features of migration and wintering: differential migration according to age and sex groups, large differences in winter densities as a response to food availability, and flocking behaviour as a response to local mass fructification of the beech Fagus sp. resulting in roosts of several million birds. This study examines (a) whether Bramblings participating in mass concentrations originate from different, or additional, breeding grounds compared with birds present in normal winters, and (b) how differential migration according to age and sex groups combines with irruptive migration and with congregations in mass roosts, i.e., whether the benefits from mass concentrations differ between age and sex groups. Wing biometry (wing length, lengths of outer primaries, and wing pointedness) did not vary geographically, as shown by museum skins, and was therefore not helpful to reveal differences in origin between birds of mass concentrations and normal winters. The extent of the post-juvenile moult was smaller in mass concentration birds and suggests that slightly later-born juveniles, i.e., born further east or north, participate in mass concentrations. Ringing recoveries could not demonstrate a difference in breeding range origin of Bramblings which participate in mass concentrations versus Bramblings in normal winters in Switzerland. However, this may be due to insufficient recoveries of ringed birds. A rough estimate suggests that the number of Bramblings migrating SW on a broad front across Europe could be sufficient to form mass concentrations of up to 10 million birds which are halted by a large area of beech mast. Across Europe, the proportion of juvenile males decreased towards south (i.e., with increasing migration distance) in autumn migrants and wintering birds, while adult females showed the opposite pattern, and adult males and juvenile females were intermediate. Mass concentrations in Switzerland were composed of significantly more adults, especially adult males, and fewer juveniles, particularly juvenile females, while the sex–age composition outside mass concentrations was similar to normal winters. Adults and females likely benefit from wintering further south where snow is less likely to cover food of this ground-feeding finch. On the other hand, the costs of migration are probably substantial in terms of direct costs or indirectly in terms of reaching the breeding grounds, so that juvenile males prefer to winter closer to the breeding area than adults. Feeding in large flocks in beech mast areas incurs the high risk of being cut off from this food by snowfall. Adult males are apparently best adapted to this risk, and hence predominate in mass concentrations.

Leg rings impact the diving performance of a foot‐propelled diver

Leg rings are frequently used to mark aquatic birds in order to identify individuals, and study population dynamics and migration patterns, with the proviso being that the rings should not affect the birds. The effects of tags and rings are of particular interest in diving birds because any change in body shape could impact swimming efficiency and costs, as water is almost a thousand times denser than air. We attached tri‐axial accelerometers to both ringed and unringed breeding Imperial Shags Leucocarbo atriceps to assess dive performance based on descent angle, descent rate, power stroke rate, power stroke peak acceleration amplitude and Vectorial Dynamic Body Acceleration (VeDBA) as a proxy for energy expenditure. Ringed birds, especially females, had a higher foot‐stroke amplitude than unringed animals. In addition, the overall efficiency of the ringed individuals, as expressed by the descent rate per unit VeDBA, was compromised (by 3.5% in females and 4.3% in males) compared with unringed birds. We conclude that leg rings change the diving performance of Imperial Shags, although the effect is small and may not affect reproductive success. However, given that birds are typically ringed for life, we urge researchers to be particularly careful about the potential cumulative effect of attaching leg rings to foot‐propelled diving species.

Evaluating consumer and clinical sleep technologies: an American Academy of Sleep Medicine update

Evaluating consumer and clinical sleep technologies: an American Academy of Sleep Medicine update

Genetic differentiation in Eurasian Woodcock (Scolopax rusticola) from the Azores

The Eurasian Woodcock Scolopax rusticola is a widespread Palaearctic migratory wader, with purportedly sedentary populations occurring in the Macaronesian archipelago of the Azores. Here we used microsatellite markers to investigate patterns of genetic diversity and differentiation in these insular birds, and compared Azorean populations with those from mainland Europe. Azorean populations show a (non‐significant) trend for reduced diversity, and low but consistent differentiation from mainland populations; evidence for widespread over‐water migration (in either direction) is weak but must occasionally occur given the recovery of an Azorean ringed bird in France. It is thus likely that the Azorean populations diverged recently from their mainland counterparts, but gene flow is currently restricted.

Modelling population dynamics and trends in migratory birds from non-standardized multi-species ringing data: the potential of multi-model selection

ABSTRACT Capsule Long-term and non-standardized migratory bird ringing data can be used in models controlling variation in bird ringing methodology for reliable population trend estimations. Aims Bird ringing data usually cover long periods and might reflect long-term population changes. However, they are mainly derived during non-standardized multi-species catching at numerous sites during the autumn migration period. We searched for the best modelling approach to determine reliable species population dynamics and trend estimation models based on annual multi-species bird ringing data. Methods We used ringing data from the Slovenian Bird Ringing Scheme and selected data in three steps according to temporal, quantitative, and qualitative data selection. Annual indices were constructed based on two types of denominators, ringing days, and ringing totals, vs. a robust model without a denominator. We ran 20 candidate-generalized additive models describing migrating population dynamics for 15 bird species by combining different data selection approaches and denominators. Results We found that the models were species-specific, although the universal model could also be applied to most species. We propose a general model construction approach for population trend assessments from non-standardized bird ringing data. The estimates obtained by this approach were comparable to the overall European population trends derived from breeding survey data. Conclusions Bird ringing data from the autumn migration period are a valuable resource for assessing continental scale population trends taking into account the whole population (non-breeders and juveniles included) and even some rare and endangered species, but should be conducted according to standard protocols to ensure reliable statistical inference of population trends.

No effect of passive integrated transponder tagging method on survival or body condition in a northern population of Black-capped Chickadees (Poecile atricapillus).

Passive integrated transponder (PIT) tags allow a range of individual‐level data to be collected passively and have become a commonly used technology in many avian studies. Although the potential adverse effects of PIT tags have been evaluated in several species, explicit investigations of their impacts on small (<12 g) birds are limited. This is important, because it is reasonable to expect that smaller birds could be impacted more strongly by application of PIT tags. In this study, we individually marked Black‐capped Chickadees (Poecile atricapillus), a small (circa 10 g) passerine, at the University of Alberta Botanic Garden to evaluate potential lethal and sublethal effects of two PIT tagging methods: attachment to leg bands or subcutaneous implantation. We used a Cox proportional hazards model to compare the apparent survival of chickadees with leg band (N = 79) and implanted PIT tags (N = 77) compared with control birds that received no PIT tags (N = 76) over the subsequent 2 years based on mist net recaptures. We used radio‐frequency identification (RFID) redetections of leg band PIT tags to evaluate sex‐specific survival and increase the accuracy of our survival estimates. We also used a generalized linear regression model to compare the body condition of birds recaptured after overwintering with leg band PIT tags, implanted PIT tags, or neither. Our analysis found no evidence for adverse effects of either PIT tagging method on survival or body condition. While we recommend carefully monitoring study animals and evaluating the efficacy of different PIT tagging methods, we have shown that both leg band and subcutaneously implanted PIT tags ethical means of obtaining individualized information in a small passerine.

Band Encounters of Oiled Birds Rehabilitated and Released by Tri-State Bird Rescue &amp; Research, Inc. between 1990–2016

Abstract Band returns provide an inexpensive and relatively passive means of evaluating survival in the wild after rehabilitation for oil contamination. Unfortunately, most encounters are made when a banded bird is shot by hunters or found dead or injured, with limited sightings of live, banded birds in the wild. This study examines band encounters received on oiled birds that were washed, rehabilitated, banded and released by Tri-State Bird Rescue and Research, Inc. (Tri-State) during the twenty-six years from 1990 to 2016. Included in these data are 228 sightings of live birds that were oiled following the Deepwater Horizon MC252 incident, and 363 encounters (live or dead) of birds impacted by other spills. Not included are birds treated by Tri-State but banded under other permits, such as the 283 birds rehabilitated and released following the 1993 Tampa Bay oil spill. Analysis of these encounters overall reveals information on species survival post-release, distance traveled by individual birds, and evidence of breeding success.

Bird Banding and the Environmental Humanities

AbstractThis article tells a history of bird banding—the practice of catching and affixing birds with durable bands with the intent of tracking their movements and behavior—by focusing on the embodied aspects of this method in field ornithology. Going beyond a straightforward, institutional history of bird banding, the article uses the writings of biologists in the US Bureau of Biological Survey and the US Fish and Wildlife Service to describe the historical practices of bird banding and the phenomenological experience of banding, both for the scientists and the birds (via their banding interlocutors). The article then presents the career and research of Margaret Morse Nice as an exemplar of the embodied practice of banding for the purposes of understanding bird behavior. Finally the article uses the example and heritage of Nice as well as banders and scientists like her to discuss a phenomenological approach common to any number of observation-based field biology disciplines (including, especially, ethology) and deep connections between human and animal subjectivities. And these connections, in turn, have implications for the environmental humanities, environmental conservation, and the ethics of knowing the nonhuman world.

Weak evidence of carry-over effects of overwinter climate and habitat productivity on spring passage of migratory songbirds at a northern stopover site in Ontario

Abstract Reduced rainfall in tropical regions decreases the availability of food resources for overwintering songbirds, with negative impacts on their body condition. Increasingly dry conditions at tropical wintering sites as a result of climate change may impact the ability of temperate-breeding songbirds to prepare for and execute their spring migration. We studied the carry-over effects of natural climatic fluctuations created by the El Niño–Southern Oscillation (ENSO) in tropical overwintering areas on 7 long-distance migratory songbirds at a Canadian stopover site. We used the Normalized Difference Vegetation Index as a proxy for tropical habitat productivity and resource availability and a 34-year bird banding dataset from Long Point, Ontario, Canada to assess migration timing and stopover body condition. To increase our ability to detect potential carry-over effects, we employed a novel approach of using recent migratory connectivity studies to restrict the wintering ranges to areas most likely used by individuals passing through southern Ontario. Using linear models, we found that overwinter habitat productivity was significantly negatively influenced by dry ENSO events in the overwintering ranges in 3 of 7 species, with a fourth near-significant. Subregional differences in the effect of ENSO on precipitation patterns may explain why we did not detect a consistent effect of ENSO on overwinter habitat productivity for all species. Despite restricting the wintering range and using a robust dataset for species with diverse life histories, we detected only weak and often conflicting evidence of population-level carry-over effects from dry ENSO events and overwinter habitat productivity. Negative carry-over effects may be strongest and most evident during the earlier stages of migration because birds may be able to compensate to some extent for poor departure condition and late departure while en route.

Post-breeding flocks of White Storks Ciconia ciconia in southern Poland: size, age composition and the geographical origin of birds

ABSTRACT Capsule White Storks Ciconia ciconia forming migrating flocks in southern Poland in autumn came from central Poland and eastern Germany, and used ploughed fields and cut meadows to forage before they moved south. Aims The aim of this study was to collect information on the flocking behaviour of the White Stork in southern Poland, with a special focus on the origins of birds forming flocks, flock size, age characteristics of birds, and habitat selection. Methods During a study conducted in 2012–2019 in southern Poland, we recorded the size, age composition and geographic origin of White Storks forming autumn flocks. The collection of the large number of records was made possible by the use of a small aeroplane during the first two years of the study, which enabled us to locate flocks over a large study area. Results In total, 5685 storks were observed, with a median flock size of eight individuals, although flock size varied during the migration period and by time of day. For the 2980 birds for which age could be determined, there was a higher proportion of adults (55.7%) than juveniles (44.3%). Analysis of data from ringed birds showed that the mean (±sd) distance travelled from natal sites was 277.3 ± 245.3 km, with birds coming mainly from southern Poland and eastern Germany. Storks foraged mainly in ploughed fields and cut meadows, and such habitats appear crucial for fuelling before migration. Conclusions Southern Poland provides an important stop-over site for migrating White Storks, which originate from a potentially large area. Hence, ensuring the continued availability of autumn foraging for White Storks in southern Poland benefits not only local birds but also a much larger population.

Population Size and Territories of Wilkins' Finches Nesospiza wilkinsi on Nightingale Island, Tristan da Cunha

Nesospiza finches are endemic to two small islands in the Tristan da Cunha Archipelago in the South Atlantic Ocean. The finches have radiated into two ecologically distinct forms at both islands: an abundant, small-billed dietary generalist, and a scarce, large-billed specialist. On Nightingale Island (area 2.6 km2), the endangered large-billed Wilkins' Finches N. wilkinsi use their strong bills to crack open the hard, nut-like fruits of Island Cape Myrtle Phylica arborea trees to access the seeds. Although Phylica fruits are available year-round, the finch population is constrained by the limited area of fruit bearing Phylica trees (c. 12 ha), which makes Wilkins' Finch one of the world's naturally rarest bird species. Prior to this study, rough estimates ranged from 30–85 pairs, but there has been no dedicated survey of the population size. Over the austral summers of 2012, 2016 and 2017 we systematically caught and colour ringed birds to better estimate the population size. Pairs were present wherever there are Phylica trees across the island, utilising even small, isolated Phylica copses. Mean territory size for 117 pairs in 2017 was 0.215 ± 0.094 ha (±SD, range 0.043–0.718) with a mean density of 9.8 pairs/ha in Phylica woodland. The total population was estimated to be 120 breeding pairs (c. 280–300 mature birds). The most pressing threat to the Wilkins' Finch population is the recent arrival of an invasive insect, the Brown Soft Scale Coccus hesperidum, and its associated sooty mould Seiridium phylicae, which reduces Phylica fruit loads and kills large trees. The potential use of a biological agent to control Brown Soft Scale infestations is being investigated, since without swift and effective mitigation, we predict the health of these woodlands will rapidly degrade with serious implications for the persistence of Wilkins' Finch. Until effective mitigation is taken, we recommend up-listing the species to Critically Endangered based on IUCN Red List Criterion B2.

Wing tags severely impair movement in African Cape Vultures

BackgroundThe use of tracking technologies is key for the study of animal movement and pivotal to ecological and conservation research. However, the potential effects of devices attached to animals are sometimes neglected. The impact of tagging not only rises welfare concerns, but can also bias the data collected, causing misinterpretation of the observed behaviour which invalidates the comparability of information across individuals and populations. Patagial (wing) tags have been extensively used as a marking method for visual resightings in endangered vulture species, but their effect on the aerodynamics of the birds and their flight behaviour is yet to be investigated. Using GPS backpack mounted devices, we compared the flight performance of 27 captive and wild Cape Vultures (Gyps coprotheres), marked with either patagial tags or coloured leg bands.ResultsIndividuals equipped with patagial tags were less likely to fly, travelled shorter distances and flew slower compared to individuals equipped with leg bands. These effects were also observed in one individual that recovered its flight performance after replacing its patagial tag by a leg band.ConclusionsAlthough we did not measure the effects of patagial tags on body condition or survival, our study strongly suggests that they have severe adverse effects on vultures’ flight behaviour and emphasises the importance of investigating the effects that tagging methods can have on the behaviour and conservation of the study species, as well as on the quality of the scientific results.

Nasal Discs and the Vital Rates of Lesser Scaup

ABSTRACTNasal discs have been used to identify ducks in studies of survival and reproduction. To date, there has not been a comprehensive assessment of nasal‐disc effects on the vital rates of wild ducks. We applied nasal discs to 603 juvenile and 784 adult lesser scaup (Aythya affinis) females from a population breeding in southwest Montana, USA, and released 1,399 juvenile and 71 adult females wearing only metal leg bands between June 2005 and September 2016. Using resighting, recapture, and hunter‐recovery data collected from those individuals, we estimated survival and recovery probability with multistate capture‐recapture models in Program MARK. We also assessed if recovery distance from our study site and pre‐breeding and brood‐rearing body condition were diminished for females wearing nasal discs. Model‐averaged survival probabilities were 0.231 ± 0.035 (SE) for juveniles and 0.482 ± 0.019 for adults released with nasal discs. Survival was 1.8–3.4 times higher for females released with metal leg bands when compared to those released with nasal discs; survival of these juveniles was 0.433 ± 0.049 and 0.693 ± 0.039 for adults. We did not find evidence for recovery probability or recovery distance varying between females that wore nasal discs and those that did not. During the pre‐breeding and brood‐rearing seasons, we did not find females wearing nasal discs to be in lower body condition when compared to unmarked females. Our comprehensive assessment of nasal discs on wild lesser scaup suggests that survival probabilities estimated from nasal‐marked study populations should be cautiously interpreted as minimum estimates. © 2021 The Wildlife Society.

100 Years of Bird Banding.

100 Years of Bird Banding.

Contrasting long‐term trends in age‐specific survival of Peregrine Falcons (Falco peregrinus) in Britain using smoothed estimates of recovery probabilities

Peregrine Falcons Falco peregrinus are an iconic species of long‐standing conservation concern as a result of historical patterns of persecution and dramatic pesticide‐related population declines in many populations during the second half of the 20th century. Although the role of reduced productivity in these declines is well known, the temporal patterns in survival are much less well characterized. We estimate survival probabilities for Peregrines in Britain in the period 1975–2018 from reports of ringed birds found dead, using a non‐parametric smoothing spline to account for non‐linear temporal variation in recovery probabilities. During this time the population increased from around 350 pairs to 1628 pairs. There was little evidence of a temporal trend in the survival probabilities of adult birds since the mid‐1970s, but survival of first‐year birds appears to have decreased. Our estimates suggest that increases in the breeding population are further limited by unreported sources of mortality or by density‐dependent processes, highlighting the need for better data on immature survival and recruitment. Modelling recovery rates using a spline, rather than independent annual values, improved estimation efficiency with lower credible intervals obtained for the adult annual estimates.

Using individual capture data to reveal large-scale patterns of social association in birds

Studying social behavior has traditionally been labor-intensive, limiting the scale of datasets and therefore the questions that can be asked. We explore the potential for large individual capture datasets, which arise from population monitoring projects such as bird banding stations, to fill this gap. Using a 23-year dataset from San Jose, CA, comprised of six passerine bird species from four families, we constructed social networks to investigate whether age-, sex-, and taxon-related patterns of social association could be detected. We found support for age-related patterns in social behavior and patterns of overall species differences that agreed with past work. We then explored interactions between species and patterns in social behavior over time, two questions that have historically been difficult to address. We detected positive assortment by taxon, and we observed a significant multi-decade decrease in mean degree. Using an agent-based simulation to allow us to independently vary behavior and aspects of the capture dataset, we found that sample size and capture probability affected the metrics that were intended to only measure social behavior, but that these confounding effects could be effectively managed in many cases. We conclude that while analysis of individual capture datasets should not replace more intensive studies of social behavior, the utilization of these data could considerably expand the scope of our knowledge of social behavior, particularly at large temporal scales and for species that are difficult to observe.

Katters predation på fåglar – ett alternativt sätt att beräkna antalet dödade fåglar

&#x0D; Many studies have tried to estimate the number of birds killed by cats, most of them based on the number of birds killed by a smaller number of cats in a local area and then scaled to larger areas, or a whole country. Such estimates can be confounded by several factors, and the results of one study may not always be applicable in another setting where climate, habitats, and societal structure differ. Here I used an alternative approach to estimate cat predation on birds using ring recoveries of birds reported to the Swedish national ringing scheme as killed by cats. With the assumption that ringed birds are taken by cats in an equal proportion as unringed birds, I estimate that about 0.03% of all passerine birds are killed by cats in Sweden annually. This amounts to about 100,000 birds per year, which is much lower than previous estimates. &#x0D;

Identification of diverse novel genomoviruses in gut of wild birds

Genomoviridae is a virus family belonging to circular replication associated protein encoding ssDNA (CRESS-DNA) viruses, which have diverse genomic architecture and are widely distributed among different ecosystems. In this study, we characterized 39 novel genomovirus genomes including 3 from wild egrets, 9 from wild cranes, as well as 27 from wild finches in three different types of cloacal swabs of wild bird sampled in the station of Xinqing bird ringing, Maoershan Nature Reserve in Heilongjiang Province, Changbai Mountain in Jilin Province, and Hangzhou Wetland Park in Zhejiang Province, China. Here, using a Rep sequence phylogeny-based analysis, we divided the 39 genomoviruses into 8 genera within the family Genomoviridae, including Gemycircularvirus (n=20), Gemykibivirus (n=3), Gemygorvirus (n=2), Gemyvongvirus (n=2), Gemykolovirus (n=3), Gemykrogvirus (n=6), Gemytondvirus (n=1), Gemyduguivirus (n=1) and one unclassified genomovirus. The 39 genomovirus genomes belong to 36 species (27 of which are new) based on the currently accepted genomovirus pairwise nucleotide sequence identity species demarcation threshold of 78%. Overall, the research enriches our knowledge of CRESS-DNA viral diversity in China and emphasizes the prevalence of genomoviruses in nature.

Overview of raptor and owl ringing in Slovakia in 2020

Abstract In 2020, 1296 raptors and owls (23 species) were ringed in Slovakia. The most abundant was the common kestrel (719 individuals), then the western marsh harrier (126) and saker falcon (92). The proportion of nestlings among all the ringed individuals was 76.7%. In the given period, 145 recoveries of raptors and owls (15 species) were recorded in the Bird Ringing Centre database. This number included 77 recoveries of colour-marked individuals recovered in our territory. There were 43 recoveries of birds ringed in Slovakia and resighted abroad. The last 25 recoveries were of individuals ringed abroad and recovered in Slovakia. In summary, most of the recoveries (of all types) were of red-footed falcon (69 recoveries), then common kestrel (17) and eastern imperial eagle (15). Most of the recovery circumstances were ring reading (almost 76% in total), findings of bird cadavers (6%) and recaptures (5%). Electrocutions and predations by other animals (3% each) were frequent causes of their deaths.