129 research outputs found
Vaux’s Swift migratory connectivity
No full textThe strength of migratory connectivity between breeding, stopover, and wintering areas can have important implications for population dynamics, evolutionary processes, and conservation. For example, patterns of migratory connectivity may influence the vulnerability of species and populations to stochastic events. For many migratory songbirds, however, we are only just beginning to understand patterns of migratory connectivity. Here, we investigate the potential strength of migratory connectivity within a population of Vaux’s Swifts (Chaetura vauxii). Vaux’s Swifts, like many aerial insectivores, are currently experiencing population declines, and a mass mortality event at a spring migratory roost on Vancouver Island, British Columbia, Canada, resulted in the death of over 1,000 individuals, representing some 2% of the British Columbia population. From these individuals, we examined variation in three stable-isotopes (δ2H, δ13C, and δ15N) from claw samples in order to determine whether spring migrants showed inherent isotopic similarity of the habitats they used on their Mexican and Central American wintering grounds. Our results indicated the presence of two to three broad isotopic clusters, suggesting that Vaux’s Swifts migrating through Vancouver Island most likely originated from two or three over-wintering locales or habitat types. We found no evidence of sex- or morphology-based segregation, suggesting that these different groups likely share a similar overwintering ecology and thus may be equally vulnerable to stochastic events or habitat loss on the wintering grounds. Our results highlight the need for more studies on the non-breeding season ecology and migratory connectivity of this species.articlesaccepted for publicationVaux’s Swiftmigratory connectivitycluster analysisstable isotopeconservationroos
Vaux’s Swift migratory connectivity
No full textPopulations of Vaux’s Swift (Chaetura vauxi), like those of many aerial insectivores, are rapidly declining. Determining
when and where populations are limited across the annual cycle is important for their conservation. Establishing the
linkages between wintering and breeding sites and the strength of the connections between them is a necessary first
step. In this study, we analyzed 3 stable isotopes (δ13C, δ15N, δ2H) from feathers collected during spring migration from
Vaux’s Swifts that perished during a stopover on Vancouver Island, British Columbia, Canada. We previously analyzed
claw tissue (grown during winter) from the same individuals, revealing that the swifts likely wintered in 2 or 3 locations/
habitats. Here, we used stable isotope analysis of flight feathers presumed to have been grown on, or near, the breeding
grounds to determine the likely previous breeding locations and presumed destinations for the swifts. Stable isotope
values (δ13C, δ15N, δ2H) showed no meaningful variation between age classes, sexes, or with body size. Surprisingly, ~26%
of the birds sampled had feather isotope values that were not consistent with growth on their breeding grounds. For the
remaining birds, assigned breeding origins appeared most consistent with molt origins on Vancouver Island. Overall, migratory connectivity of this population was relatively weak (rM = 0.07). However, the degree of connectivity depended on
how many winter clusters were analyzed; the 2-cluster solution suggested no significant connectivity, but the 3-cluster
solution suggested weak connectivity. It is still unclear whether low migratory connectivity observed for Vaux’s Swift and
other aerial insectivores may make their populations more or less vulnerable to habitat loss; therefore, further efforts
should be directed to assessing whether aerial insectivores may be habitat limited throughout the annual cycle.Peer reviewedarticlespublishedVaux’s Swiftaerial insectivoresChaetura vauximigrationmigratory connectivitypopulation declinesstable isotopesstopove
Hardwarekeuze voor het El Condor Soundsystem: Aanbevelingsrapport voor optimale hardware
No full textProfessionele muzikanten gaan naar een opnamestudio als ze een album willen opnemen van hoge geluidskwaliteit. Voor de beginnende muzikant zijn deze studio’s echter niet te betalen, aangezien een opname minstens \u801500 kost. Het aanschaffen van eigen opnameapparatuur is nog vele malen duurder. In die hoge prijs gaat het El Condor Soundsystem verandering brengen. Het El Condor Soundsystem is een draagbaar apparaat, dat een ruimteopname van gespeelde muziek vastlegt, bewerkt en opslaat als bestand dat leesbaar is op elke PC. Het El Condor Soundsystem kan dankzij zijn algoritmes verschillende bronnen onderscheiden zonder hier een fysieke verbinding mee te hebben. De verschillende geluidssporen worden gebruikt om de muziek automatisch te verfraaien en daarna worden deze weer gemixt tot één eindproduct met CD-kwaliteit. Voor het bewerken en wegschrijven is veel rekenkracht nodig. Daarom wordt in dit rapport antwoord gegeven op de vraag: met welke hardware kun je het El Condor Soundsystem zo efficiënt (en dus goedkoop) mogelijk implementeren?EEMicroelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Predicting condor range expansion in California to reduce development threats
No full text2020 Summer.Includes bibliographical references.Collisions with wind energy infrastructure is a major cause of wildlife mortality worldwide and especially pose threats to bird and bat populations. Avian species that have associations with habitats that generate strong winds are at higher risk of collision with wind turbines. Critically endangered California condors (Gymnogyps californianus) are among species that use areas with high-class winds. As the condor's population growth continues to face challenges, it is imperative that managers working with the California Condor Recovery Program identify and reduce all threats to the species and foster conditions that promote condor recovery. Renewable energy projects, particularly wind energy, pose risks to condors; and new developments within current, documented condor range require planning and consultation with the United States Fish and Wildlife Service. However, industrial-scale wind energy projects in California consider condor flocks in central and southern California separate and statically persisting within their current ranges. This misconception may result in development within condor habitat that is detrimental to range expansion and recovery. In this thesis, I examine factors that influence condor home range sizes, predict where condors are likely to expand their range within identified suitable habitat in California, and assess where the predicted condor range overlaps with areas that generate high-class winds preferred for wind energy development. My first chapter focuses on estimating annual home ranges of condors and identifying factors that influence home range size. Understanding what intrinsic and extrinsic variables influence condor home ranges can inform management planning and aid in predicting condor range expansion. I used location data collected from condors released in central and southern California to estimate annual condor home range area and assessed twenty-one variables related to individual characteristics, management factors, population dynamics, and habitat suitability to identify strong predictors of home range size. I found that age group, time spent in the wild, age of managing agency, maximum slope, maximum NDVI, distance to water, and road density were significant predictors of annual home range area. On average, adult breeding condors had the smallest home range areas and subadult condors had the largest home range areas. Population size did not affect annual home range size of condors; however, home range size increased the longer a managing agency had been releasing condors. My objective of the second chapter was to predict condor range expansion in California and identify where there may be conflict between condors and potential wind energy development. Predicting condor range expansion may inform managers of areas to concentrate efforts and resources for management and outreach, as well as identify areas that should be considered during wind energy development planning stages to reduce risks to condor recovery. I used the results from Chapter 1 and a habitat suitability surface to create a tool in which a user can customize the demographics of condor flocks in California sometime in the future and predict the overlapping home ranges of individuals in the flocks. Users can then export the predicted ranges into a GIS program to consider how the overlapping home ranges may be affected by plans for wind energy development and identify possible alternative sites. I predicted condor range expansion in California under four scenarios: 1) population size and structure stays the same (2019 California population); 2) each flock has 150 individuals with 15 breeding pairs; 3) each flock has a majority of breeding pairs, which maximizes breeding pairs and minimizes sub-adult condors; and 4) each flock has a majority of subadults, which maximizes subadult condors and minimizes breeding pairs. Predicted ranges under different scenarios exhibited high similarity and areas with high-class wind generation overlapped with <10% of predicted condor range under all scenarios. More than 81% of areas with strong winds suitable for energy generation were unaffected by predicted condor range, suggesting there are alternative areas for wind energy development with less risk of conflict with critically endangered California condors
The endangered California Condor (Gymnogyps californianus) population is exposed to local haemosporidian parasites
No full text© 2020, The Author(s). The endangered California Condor (Gymnogyps californianus) is the largest New World Vulture in North America. Despite recovery program success in saving the species from extinction, condors remain compromised by lead poisoning and limited genetic diversity. The latter makes this species especially vulnerable to infectious diseases. Thus, taking advantage of the program of blood lead testing in Arizona, condor blood samples from 2008 to 2018 were screened for haemosporidian parasites using a nested polymerase chain reaction (PCR) protocol that targets the parasite mitochondrial cytochrome b gene. Plasmodium homopolare (Family Plasmodiidae, Order Haemosporida, Phylum Apicomplexa), was detected in condors captured in 2014 and 2017. This is the first report of a haemosporidian species infecting California Condors, and the first evidence of P. homopolare circulating in the Condor population from Arizona. Although no evidence of pathogenicity of P. homopolare in Condors was found, this study showed that the California Condors from Arizona are exposed to haemosporidian parasites that likely are spilling over from other local bird species. Thus, active surveillance should be an essential part of conservation efforts to mitigate the impact of infectious diseases, an increasingly recognized cause of global wildlife extinctions worldwide, particularly in avian populations considered vulnerable or endangered
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The condor song
No full textnspired by the Sierra Club 1960’s battle with the Walt Disney company over a proposed ski resort in the Sierra Nevada Mountains, former attorney and best selling author, Darryl Nyznyk, brings captivating realism to this riveting new thriller.Sean Donovan lost everything: his wife, kids, job, and license to practice law. Abandoned by his wife, betrayed by a friend, and fired by his firm, it has taken thirteen years for Sean to come back, now barely eking out a living on minor cases while his former firm thrives.When Buck Anderson, renowned environmentalist from Sean’s hometown is murdered, Sean reunites with Buck’s niece at the old man’s funeral. She begs Sean to join the Sierra Club’s case to stop a major ski development by a Disney-type company, the very case on which Buck was working when he was killed. Sean agrees, but learns too late that his former firm represents the opposition with motives more sinister than their client’s ski development.THE CONDOR SONG is an environmental legal thriller set against California’s rugged Sierra Nevada Mountains in which a man lost to the world he thought he knew tries to find redemption in the face of impossible odds.https://scholarship.law.ua.edu/harper_lee_prize_books_2014/1011/thumbnail.jp
The condor song
No full textnspired by the Sierra Club 1960’s battle with the Walt Disney company over a proposed ski resort in the Sierra Nevada Mountains, former attorney and best selling author, Darryl Nyznyk, brings captivating realism to this riveting new thriller.Sean Donovan lost everything: his wife, kids, job, and license to practice law. Abandoned by his wife, betrayed by a friend, and fired by his firm, it has taken thirteen years for Sean to come back, now barely eking out a living on minor cases while his former firm thrives.When Buck Anderson, renowned environmentalist from Sean’s hometown is murdered, Sean reunites with Buck’s niece at the old man’s funeral. She begs Sean to join the Sierra Club’s case to stop a major ski development by a Disney-type company, the very case on which Buck was working when he was killed. Sean agrees, but learns too late that his former firm represents the opposition with motives more sinister than their client’s ski development.THE CONDOR SONG is an environmental legal thriller set against California’s rugged Sierra Nevada Mountains in which a man lost to the world he thought he knew tries to find redemption in the face of impossible odds.https://scholarship.law.ua.edu/harper_lee_prize_books_2014/1011/thumbnail.jp
“The Right to the City” An Ecosystemic Approach to Better Cities, Better Life
No full textUrbanism is a focus on cities and urban areas, their geography, economies, politics, social characteristics, as well as the effects on, and caused by, the built environment; it is linked to various aspects of quality of life: education, culture, justice, labour, environment, health, safety, housing, leisure, transport, consumption. This year, the United Nations proposed the following questions for the citizens of the world: What is the best thing about your city? What's the worst thing about your city? What do you want the authorities to do about it? What can you do about it? It is a clear attempt to foster civic participation and personal engagement, but to make things happen it is necessary to create active socio-cultural niches at many societal levels.Urbanism; politics; education; culture; justice
[Review of] Sabine R. Ulibarri. El Condor and Other Stories
No full textThis volume continues in the same vein as Governor Glu Glu, but Ulibarri here delves even more deeply into the world of fantasy. Many of the eleven stories in El Condor are like sugar-coated medicine: the sweetness prepares the reader for the lesson which comes in the form of a moral at the end. The Man Who Didn\u27t Eat, for example, is a tale of the scientific creation of a man who is vegetable Frankenstein\u27s monster, with parts taken from many plants. The creature in Ulibarri\u27s story is benevolent; as a result of his superhuman effort to save his neighbors from a plague to which he is immune, he misses his nutritional injection and dies. Ulibarri concludes with his lesson: No one ever knew, neither in the lay world nor in the scientific world, that a living miracle had lived among us. We do not know how to recognize the miracles that surround us. In A Man Who Forgot, the author presents a self-conscious story about a man who remembers only what is good. The moral here is, how beautiful life would be if we could erase from our memory all that is ugly, and remember only the beautiful and the good
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