Browsing by Author "Taylor A"

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    Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds.
    (2016) Weiser EL; Lanctot RB; Brown SC; Alves JA; Battley PF; Bentzen R; Bêty J; Bishop MA; Boldenow M; Bollache L; Casler B; Christie M; Coleman JT; Conklin JR; English WB; Gates HR; Gilg O; Giroux M-A; Gosbell K; Hassell C; Helmericks J; Johnson A; Katrínardóttir B; Koivula K; Kwon E; Lamarre J-F; Lang J; Lank DB; Lecomte N; Liebezeit J; Loverti V; McKinnon L; Minton C; Mizrahi D; Nol E; Pakanen V-M; Perz J; Porter R; Rausch J; Reneerkens J; Rönkä N; Saalfeld S; Senner N; Sittler B; Smith PA; Sowl K; Taylor A; Ward DH; Yezerinac S; Sandercock BK
    BACKGROUND: Geolocators are useful for tracking movements of long-distance migrants, but potential negative effects on birds have not been well studied. We tested for effects of geolocators (0.8-2.0 g total, representing 0.1-3.9 % of mean body mass) on 16 species of migratory shorebirds, including five species with 2-4 subspecies each for a total of 23 study taxa. Study species spanned a range of body sizes (26-1091 g) and eight genera, and were tagged at 23 breeding and eight nonbreeding sites. We compared breeding performance and return rates of birds with geolocators to control groups while controlling for potential confounding variables. RESULTS: We detected negative effects of tags for three small-bodied species. Geolocators reduced annual return rates for two of 23 taxa: by 63 % for semipalmated sandpipers and by 43 % for the arcticola subspecies of dunlin. High resighting effort for geolocator birds could have masked additional negative effects. Geolocators were more likely to negatively affect return rates if the total mass of geolocators and color markers was 2.5-5.8 % of body mass than if tags were 0.3-2.3 % of body mass. Carrying a geolocator reduced nest success by 42 % for semipalmated sandpipers and tripled the probability of partial clutch failure in semipalmated and western sandpipers. Geolocators mounted perpendicular to the leg on a flag had stronger negative effects on nest success than geolocators mounted parallel to the leg on a band. However, parallel-band geolocators were more likely to reduce return rates and cause injuries to the leg. No effects of geolocators were found on breeding movements or changes in body mass. Among-site variation in geolocator effect size was high, suggesting that local factors were important. CONCLUSIONS: Negative effects of geolocators occurred only for three of the smallest species in our dataset, but were substantial when present. Future studies could mitigate impacts of tags by reducing protruding parts and minimizing use of additional markers. Investigators could maximize recovery of tags by strategically deploying geolocators on males, previously marked individuals, and successful breeders, though targeting subsets of a population could bias the resulting migratory movement data in some species.
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    Enhancing the value of weather and climate services in society - identified gaps and needs as outcomes of the 1st WMO WWRP/SERA “Weather and Society” Conference
    (American Meteorological Society, 2023-02-14) Göber M; Isadora C; Hoffmann D; Mooney CJ; Rodriguez L; Becker N; Ebert EE; Fearnley C; Fundel VJ; Golding B; Jeurig J; Kelman I; Kox T; Magro F-A; Perrels A; Postigo JC; Potter SH; Robbins J; Rust H; Schoster D; Tan M; Taylor A; Williams H
    What: The Societal and Economics Research Application (SERA) Working Group of the World Meteorological Organization (WMO) World Weather Research Programme (WWRP) organized the first Weather and Society Conference, inviting the weather community to actively engage on critical themes to understand, analyze, and enhance the value of weather and climate services in society. The online conference ran over 2 weeks. Each session focused on a theme, ran for two hours, and included talks and discussion followed by a one-hour poster session. When: 28 February to 11 March 2022 Where: Online.
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    Protecting the future of New Zealand’s freshwater ecosystems
    (Society for Conservation Biology (Oceania), Sydney, 1/09/2014) Weeks E; Kingsford RT; Taylor A; Joy MK
    Freshwater is New Zealand’s greatest asset and is a taonga of paramount importance. It is valued for its contribution to biodiversity, recreation, the economy and overall well - being of New Zealanders. New Zealand’s rivers, lakes, wetlands and groundwater support a unique array of flora and fauna. They are also a vital element of whakapapa and provide valuable resources such as mahinga kai, and underpin the country’s ever - growing tourism industry. Reinforcing this importance, New Zealanders consider water quality to be the most important environmental challenge facing New Zealand. This Conservation Science Statement uses the latest scientific understanding of New Zealand’s unique freshwater ecosystems to propose approaches to policy and management that safeguard these resources for future generations. We identify six clear priorities to protect New Zealand’s freshwater ecosystems: 1. address the cumulative impacts of land use change and resulting diffuse pollution of rivers and streams ; 2. build capacity to sustainably manage freshwater ecosystems at the regional level ; 3. support whole farm environmental management to control water quality impacts ; 4. develop a management agenda for wetlands and groundwater ecosystems ; 5. enhance the understanding of the ecological requirements to sustain native fish habitat through Department of Conservation, the Land and Water Forum site and other agencies and; 6. identify impacts of increased allocation on surface and ground water ecosystems and synergies with declining water quality.
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    Quantitative measurements of enlarged perivascular spaces in the brain are associated with retinal microvascular parameters in older community-dwelling subjects
    (Elsevier BV, 21/08/2020) Ballerini L; McGrory S; Hernández M; Lovreglio R; Pellegrini E; Muñoz Maniega S; Henderson R; Taylor A; Bastin ME; Doubal F; Trucco E; Deary IJ; Wardlaw J; MacGillivray T
    Background Perivascular Spaces (PVS) become increasingly visible with advancing age on brain MRI, yet their relationship to morphological changes in the underlying microvessels remains poorly understood. Retinal and cerebral microvessels share morphological and physiological properties. We compared computationally-derived PVS morphologies with retinal vessel morphologies in older people. Methods We analysed data from community-dwelling individuals who underwent multimodal brain MRI and retinal fundus camera imaging at mean age 72.55 years (SD=0.71). We assessed centrum semiovale PVS computationally to determine PVS total volume and count, and mean per-subject individual PVS length, width and size. We analysed retinal images using the VAMPIRE software suite, obtaining the Central Retinal Artery and Vein Equivalents (CRVE and CRAE), Arteriole-to-Venule ratio (AVR), and fractal dimension (FD) of both eyes. We investigated associations using general linear models, adjusted for age, gender, and major vascular risk factors. Results In 381 subjects with all measures, increasing total PVS volume and count were associated with decreased CRAE in the left eye (volume β=−0.170, count β=−0.184, p<0.001). No associations of PVS with CRVE were found. The PVS total volume, individual width and size increased with decreasing FD of the arterioles (a) and venules (v) of the left eye (total volume: FDa β=−0.137, FDv β=−0.139, p<0.01; width: FDa β=−0.144, FDv β=−0.158, p<0.01; size: FDa β=−0.157, FDv β=−0.162, p<0.01). Conclusions Increase in PVS number and size visible on MRI reflect arteriolar narrowing and lower retinal arteriole and venule branching complexity, both markers of impaired microvascular health. Computationally-derived PVS metrics may be an early indicator of failing vascular health and should be tested in longitudinal studies.