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The effects of surface water acidification on riparian birds - with particular reference to the DipperVickery, Juliet January 1988 (has links)
No description available.
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A systematic conservation plan for threatened freshwater wetlanddependent waterbirds across South AfricaDaniels, Neil January 2020 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) - MSc (Biodiv and Cons Biol) / Freshwater ecosystems are valuable to all components of biodiversity communities. Globally, these
ecosystems are threatened by human activity and as a consequence, many vertebrates, including
waterbirds, have become threatened. Wetlands are one of the most productive ecosystem types in
the world. Yet, despite this, many protected area networks around the world fail to include this
ecosystem type in their protected area networks. On a national scale, in South Africa, wetland loss
and deteriorating wetland habitat quality continues to restrict and reduce the range of wetland
waterbirds. For this thesis, Maximum Entropy (MaxEnt) species distribution modelling was used to
identify additional areas of possible waterbird occurrence. The MaxEnt results noted that waterbirds
rely on a combination of these environmental variables for their distribution ecology in their wetland
habitat, with vegetation and humidity variables having the highest predictive powers. These would
be considered important predictor variables for the distribution ecology of these waterbirds.
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Winter Waterbird Use and Food Resources of Aquaculture Lands in MississippiFeaga, James Stephen 17 May 2014 (has links)
The conversion of wetland systems to aquaculture provides alternate aquatic habitats for a variety of waterbirds. In response to the 2010 British Petroleum oil spill, the National Resource Conservation Service (NRCS) enacted the Migratory Bird Habitat Initiative (MBHI) through which NRCS partnered with landowners to provide additional wetlands and associated foraging habitat for migrating waterbirds. During winters 2011–2013, I estimated abundances of waterbirds, seeds, and invertebrates in six production and idled aquaculture facilities in the Mississippi Alluvial Valley. Wintering waterbirds exhibited similar densities on production (i.e., ~22 birds/ha) and idled (i.e., ~20 birds/ha) MBHI sites. My results suggest production and idled MBHI aquaculture impoundments produced suitable conditions for waterbirds in terms of food and habitat. I recommend future programs strive to enroll properties that promote an increased diversity of habitats in terms of vegetation structure, available forage, and varying water depth, with the aim of maximizing waterbird diversity.
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What Would a Waterbird Do? An Annual Study of 13 Urban Wetlands in Frisco, TexasProctor, Jayce Alan 05 1900 (has links)
Intention for this study is driven by finding patterns that may be shown to reveal primary factors of influence for the abundance and diversity of wetland birds. These correlations may be used to promote wetland management strategies for the benefit of waterbird species, and help illuminate current local wetland conditions for waterbirds, respectively. The idea is to help enliven individuals to become a more conscious steward and manipulator of our environment through incorporating structural and biological components into wetland development and management strategies, and broadly speaking, urban development practices.
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Evaluating the Responses of Least Terns, Common Terns, Black Skimmers, and Gull-billed Terns to Military and Civilian Aircraft and to Human Recreation at Cape Lookout National Seashore, North CarolinaHillman, Matthew Dean 28 September 2012 (has links)
Due to variability in aircraft overflight type and associated animal responses, there is a lack of consensus on the effects of overflights on wildlife populations. My objectives were to 1) evaluate the potential impacts that reduced-altitude tactical speed military aircraft might generate on nesting colonial waterbirds, and to place any impacts in the context of other human events, 2) a) identify key least tern (Sternula antillarum) demographic drivers, b) evaluate the accuracy of assigning nest fates without using remote cameras, and c) assess the effects of camera-monitoring on nest survival, and 3) evaluate the agreement between two techniques used to estimate peak least tern breeding abundance. I conducted my study at Cape Lookout National Seashore, North Carolina from May-August 2010-2012. I surveyed colonies once every 3-5 days and deployed audio recorders and time-lapse cameras at individual nests in 9 colonies. Birds did not incubate less or engage in alert behaviors during overflights compared with control periods. Least terns reduced incubation by a mean of 12% when pedestrians were observed near nests (S = -2.2, p = 0.04). Demographic effects from overflights or recreation are unlikely given the patterns of use in this study. Least tern demographic rates were driven by raccoon depredation. Cameras reduced daily nest survival (SE) from 0.85 (0.06) to 0.79 (0.08). However, cameras also decreased the frequency of unknown or misclassified nest fates by > 30%. Incubating adult counts were effective in assessing peak nest abundance at colonies where topography did not impede scanning from the perimeter. / Master of Science
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Efeitos da antropização da zona costeira sobre as assembléias de avesMäder, Aurélea 25 February 2010 (has links)
Made available in DSpace on 2015-03-05T16:20:41Z (GMT). No. of bitstreams: 0
Previous issue date: 25 / Nenhuma / Áreas urbanizadas afetam negativamente a distribuição, abundância e comportamento de aves aquáticas costeiras. Neste estudo nós testamos a hipótese de que áreas costeiras perturbadas pelo homem (1) possui menor abundância e riqueza de aves, (2) diferenciação na composição de espécies e (3) apresenta um padrão temporal de abundância diferente de áreas costeiras não urbanizadas. Para isso, utilizamos 16 sub-áreas na costa do Rio Grande do Sul (8 não-urbanizadas e 8 urbanizadas). Foram registradas 73.893 aves no estudo, destes 46.295 (63%) indivíduos foram registradas no litoral médio (não-urbanizado) e 27.598 (37%); no litoral norte (urbanizado). A riqueza foi similar entre as duas áreas, mas a quantidade de indivíduos que ocorreram nas praias diferiu significativamente. Aves migratórias neárticas, assim como os representantes da ordem sub-ordens Scolopaci e Lari são mais abundantes no litoral médio, enquanto os Ciconiiformes, Falconiformes e Passeriiformes são mais encontrados no litoral norte. Observamos um a / Urbanized areas negatively affect the distribution, abundance and behavior of coastal waterbirds. In this study we tested the hypothesis that coastal areas disturbed by man (1) has a lower abundance and diversity of birds, (2) differentiation in species composition and (3) presents a different temporal pattern of abundance of undeveloped coastal areas. For this, we use 16 sub-areas on the coast of Rio Grande do Sul (8 non-urbanized and urbanized 8). 73 893 birds were recorded in the study, these 46 295 (63%) individuals were recorded on the coast average (non-urbanized) and 27 598 (37%) on the north coast (urbanized). Richness was similar between the two areas, but the amount of individuals that occurred on the beaches differed significantly. Nearctic migratory birds, as well as representatives of the order sub-orders Scolopaci and Lari are more abundant in the coastal average, while Ciconiiformes, Falconiformes and Passeriiformes are mostly found in the north coast. We observed a significant increase for som
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Didžiųjų ančių užsikrėtusių paukščių gripo virusu molekuliniai tyrimai / The molecular analysis of mallards infected by avian influenza virusTrapnauskaitė, Katrė 11 June 2014 (has links)
Paukščių gripas yra virusinė infekcija, kuri lengvai plintanti pavojinga užkrečiamoji paukščių liga, šia liga serga laukiniai ir naminiai paukščiai. Patys pavojingiausi ir patogeniškiausi yra paukščių gripo H5 ir H7 viruso potipiai. Didžiausią susirūpinimą ir nerimą kelia H5N1 paukščių gripo virusas, kuris priklauso Influenzavirus A viruso atmainai. Svarbiausias antigenas, kuris sukelia apsauginių antikūnų produkciją, o taip pat svarbus viruso prisijungimui prie ląstelių pirmosiose infekcijos stadijose, yra viriono apvalkalo glikoproteinas - hemagliutininas. Pagal hemagliutinino antigenines savybes virusas skirstomas į 16 potipių (H1-H16). Žmonės serga H1, H2 ir H3 potipiais, tačiau visada išlieka galimybė, kad įvykus geno mutacijoms, poslinkiams ar pasikeitus genetinei informacijai pavojingi taps ir likę potipiai. Todėl yra būtina stebėti, kokie A tipo gripo viruso potipiai vyrauja. Darbe yra apžvelgta didžiųjų ančių (Anas platyrhynchos) bendra charakteristika, literatūriniai duomenys apie paukščių gripo virusą, aprašytas polimerazinės grandininės reakcijos metodas, tikro laiko ir atvirkštinės transkripcijos polimerazinės grandininės reakcijos eiga. Skyriuje „Medžiagos ir metodai“ aprašyta, kokia medžiaga buvo naudota tyrimuose, aprašytas RNR išskyrimas ir gryninimas, naudojami rinkiniai. Aprašyta paukščių gripo A viruso H5 ir H7 potipių nustatymas vieno žingsnio realaus laiko atvirkštinės transkripcijos PGR būdu.
Iš viso 949 vandens paukščių mėginiai buvo surinkti Lietuvoje... [toliau žr. visą tekstą] / Avian influenza is a viral infection that is easily spread through a dangerous contagious disease of birds that disease sick in wild and domestic birds. The most dangerous and pathogenicity are avian influenza H5 and H7 virus subtypes. The biggest concern and disturbing of the H5N1 avian influenza virus, which belongs to Influenza A Virus species. The aim was to analyze the mallards which was infected by avian influenza virus in Lithuania
At work is reviewed mallards (Anas platyrhynchos) general characteristics, the literature results of the avian influenza virus, described polymerase chain reaction method and real time reverse transcriptase polymerase chain reaction process.
In chapter „Materials and Methods” describes what material was used in the research described in RNA isolation and purification for use in kits. Described by avian influenza A virus of the H5 and H7 subtypes of setting a one-step real-time reverse transcription PCR.
319 influenza A virus samples from which 22 samples were positive for influenza A virus. Also during the year 2007 to get 630 influenza A virus samples from 43 of the positive samples. After the 2007 and 2011 data analysis reveals that the majority of the positive influenza A samples of migratory birds have been obtained during the cold season. Haemagglutinin subtypes used successfully to identify by the Blast search GenBank database.
Avian influenza viruses positive samples were identified exclusively from mallards, hunted in various... [to full text]
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Hur har häckande våtmarksfåglar svarat på restaureringar utförda i Kvismarens naturreservat, Närke? / How have breeding wetland birds responded to wetland restorations carried out in Lake Kvismaren, Sweden?Persson, Magnus January 2022 (has links)
Näringsrika våtmarker i odlingslandskapet tenderar med tiden att växa igen vilket innebär förlust av biologisk mångfald. Att bekämpa igenväxning och föryngra den ekologiska successionen genom våtmarksrestaurering är ett sätt att få tillbaka fågellivet i våtmarker. Kvismarens naturreservat har restaurerats vid flera tillfällen och Kvismare fågelstation har inventerat fågellivet sedan 60-talet till idag. Hur har art- & individrikedomen bland häckande våtmarksfåglar förändrats i takt med att restaureringar i Kvismaren utförts? Sex restaureringar har valts ut som studieobjekt. För dessa sex restaureringar sammantaget uppvisas en tydligt ökande trend för både antal häckande arter och antal häckande par men utan statistisk signifikans. Vissa enskilda restaureringar uppvisar en signifikant ökning av både antal häckande arter och par (t.ex. Fågelsjöns restaurering 1986). Somliga artgrupper inom våtmarksfåglar kan efter vissa restaureringar visa stort uppsving, t.ex. vadare (Charadrii) som ökade med 464% efter Rysjöns restaurering 1997. Om målet med en restaurering är att öka biodiversiteten av häckande våtmarksfåglar föreslår min data att förvaltare bör satsa mer resurser på s.k. totalrestaureringar (t.ex. Rysjön 1981 & Sörbysjön 2013) hellre än s.k. nyrestaureringar. Vid en jämförelse av våtmarksinventering för Kvismarens totala yta med 40 års mellanrum (1980 & 2020) påvisas en ökning med 4 fler häckande våtmarksarter och 1 039 fler häckande par. Resultaten tyder på att restaureringar i Kvismarens våtmarker under 40 år har lönat sig, i synnerhet tack vare totalrestaureringar. / Nutrient-rich wetlands in agricultural landscape tend to become overgrown over time which means loss of biodiversity. Combating overgrowth and rejuvenating ecological succession through wetland restoration is an approach to get bird life back in wetlands. Wetlands in Kvismaren’s nature reserve, central Sweden, has been restored on several occasions and Kvismare Bird Observatory has inventoried bird life since the ‘60s until today. How has species & individual richness among breeding wetland birds changed as various wetland restorations in Kvismaren have been carried out? Six restorations in four sub-areas in Kvismaren have been selected as study objects. For these six restorations combined, a clearly increasing trend is shown for both the number of breeding species and pairs, but without statistical significance. Some restorations individually, however, show a significant increase in the number of breeding species and pairs (e.g. Fågelsjön's restoration in 1986). Some species groups within wetland birds can after certain restorations show great upswing, e.g. waders (Charadrii) that went from 14 to 79 breeding pairs (+464%) after Rysjön's restoration in 1997. If the goal of a restoration is to raise the biodiversity of breeding wetland birds, my data suggests that managers should invest more resources in so-called total-restorations (e.g. Rysjön 1981 & Sörbysjön 2013) rather than so-called new-restorations. A comparison of the wetland census for Kvismaren's total area at 40-year intervals (1980 & 2020) shows an increase of 4 more breeding wetland species and 1,039 more pairs. These results show that wetland restorations in Lake Kvismaren for 40 years have paid off, especially thanks to total-restorations.
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Waterbird and Seed Abundances in Migratory Bird Habitat Initiative and Non-Managed Wetlands in Mississippi and LouisianaWeegman, Matthew Moraco 14 December 2013 (has links)
The USDA Natural Resources Conservation Service (NRCS) implemented the Migratory Bird Habitat Initiative (MBHI) in summer 2010 to provide wetlands for waterbirds inland from the Deepwater Horizon Oil Spill. To evaluate MBHI and associated wetland management practices, I estimated seed and waterbird densities in MBHI and non-managed wetlands in the Mississippi Alluvial Valley (MAV) of Mississippi and Louisiana. Although not statistically different, wetlands enrolled in MBHI contained 1.26 and 1.53 times more seed biomass and seeds consumed by waterfowl than non-managed wetlands, respectively. I also detected 3 times more dabbling ducks and all ducks combined on MBHI wetlands. When I combined density data for all waterbird species, MBHI wetlands contained more than 2 times as many birds than control wetlands. Management via MBHI increased waterbird and potential food abundances, suggesting NRCS consider sustaining MBHI and provide financial incentives to landowners for management of wetlands in the MAV and United States.
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Fall Migrant Waterbird Community Structure and Stable Isotope Ecology in the Mississippi Alluvial Valley and Northern Gulf of Mexico: Use of Migratory Bird Habitat Initiative Sites and Other WetlandsFoth, Justyn Richard 09 December 2016 (has links)
The Mississippi Alluvial Valley (MAV) was dominated by extensive lowland forests, but during the 20th century most of the MAV was converted to agricultural, aquaculture, and other human uses. These land-use changes created stopover migration and wintering habitats for waterfowl, shorebirds and other waterbird species. Before landscape modification of the MAV, shorebirds likely migrated past the MAV to wetlands along the northern Gulf of Mexico (NGoM). In 2010, the Deepwater Horizon oil spill impacted coastal marshes of the NGoM. The USDA Natural Resources Conservation Service implemented the Migratory Bird Habitat Initiative (MBHI) to provide waterbirds with wetlands inland of oil-impacted areas. My objectives were to 1) statistically model the waterbird community on wetlands in the MAV and NGoM, 2) estimate relative abundance of shorebird and other waterbirds in idled aquaculture ponds enrolled in MBHI and associated wetlands in the MAV and NGoM, and 3) collect shorebird feathers and blood for stable isotope analysis (13C/12C, 15N/14N) to assess foraging niches and potential migratory connectivity between MAV and NGoM habitats during 2012 – 2013. Consequently, autumns of these years were under a drought, extensively wet from Hurricane Isaac, and exhibited average precipitation in the post-hurricane recovery period which may have had an effect on waterbird assemblages differing by year, month, twice-monthly survey period, latitude, region, state, site, and water depth index. Latitude shifted north and water depth was narrowest when abundant wet habitat existed on the landscape in 2012. Bird abundances were greatest in 2011 and never recovered to these levels in 2012 or 2013, which may have reflected effects of drought concentrating birds on remaining wetlands in 2011 and subsequent to the hurricane. Stable isotope analysis of blood indicated spatial segregation of shorebird species. Neither blood nor feather carbon and nitrogen values revealed definitive linkage of sites between the MAV and NGoM. Shallow water habitat inland may be a limiting resource during migration for waterbirds, especially in drought years when other wetlands may have been limited. Thus, provision of wetlands (mudflat – 15 cm) by MBHI and other conservation strategies across the landscape may allow waterbirds access to needed resources during migration.
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