Academic literature on the topic 'Migratory waterfowl'

Most migratory birds depend on stopover sites, which are essential for refueling during migration and affect their population dynamics. In the East Asian–Australasian Flyway (EAAF), however, the stopover ecology of migratory waterfowl is severely under-studied. The knowledge gaps regarding the timing, intensity and duration of stopover site usages prevent the development of effective and full annual cycle conservation strategies for migratory waterfowl in EAAF. In this study, we obtained a total of 33,493 relocations and visualized 33 completed spring migratory paths of five geese species using satellite tracking devices. We delineated 2,192,823 ha as the key stopover sites along the migration routes and found that croplands were the largest land use type within the stopover sites, followed by wetlands and natural grasslands (62.94%, 17.86% and 15.48% respectively). We further identified the conservation gaps by overlapping the stopover sites with the World Database on Protected Areas (PA). The results showed that only 15.63% (or 342,757 ha) of the stopover sites are covered by the current PA network. Our findings fulfil some key knowledge gaps for the conservation of the migratory waterbirds along the EAAF, thus enabling an integrative conservation strategy for migratory water birds in the flyway.

Assessment of aquatic plant selection by waterfowl has been conducted during the winters of 1997-2000 on 49 0.2-0.79 ha research ponds in north central Texas. Ponds were categorized by dominant plant species into eight habitat types. Census with waterfowl species identification were performed to investigate impacts of aquatic vegetation and water depth on waterfowl. Eighteen waterfowl species were observed. Peak migration occurred in late December/early January. Mixed native ponds and mixed native/hydrilla ponds were the most frequently selected habitat types. The study included correlation analysis between pond water levels and waterfowl use. Full ponds received greatest use followed by half full ponds, while almost empty ponds received minimal use. Time activity budgets were conducted on waterfowl utilizing mixed native and hydrilla ponds to compare waterfowl time partitioning on native aquatic vegetation versus hydrilla. Although only minor differences were found in time budgets, social status appears to be strongly related to habitat selection. Ducks on native ponds were paired (86%), conversely no ducks on hydrilla ponds were paired. Hydrilla pond although frequently utilized, were populated by lower status birds mostly single hens.

In Canada, regulations against the use of lead (Pb) shot for waterfowl hunting were first established in the early 1990s with the creation of a few non-toxic shot zones, and culminated with a national ban in 1997. Prior to establishment of the first non-toxic shot zones in Canada, a nation-wide survey of Pb accumulation in wing bones of young-of-the-year (YY) dabbling and diving ducks determined the incidence of elevated Pb exposure in different parts of the country (Scheuhammer & Dickson, 1996). The objective of the present study was to determine the incidence of elevated Pb accumulation in the same species several years after the national ban on Pb shot; to survey waterfowl hunters to determine approximate levels of compliance with the Pb shot ban; and to use stable Pb isotope analysis to help determine the relative importance of different sources of Pb exposure.<br>Wing bones from 721 YY black, mallard, and ring necked ducks, and 579 YY woodcock from selected zones in Ontario, Quebec, BC, and the Maritimes, Canada were analyzed for Pb using flame atomic absorption spectrometry. (Abstract shortened by UMI.)

Anseriformes mantidos em lagos de zôos e parques estão sob constante risco de exposição às doenças presentes nas populações de aves migratórias, que dividem com eles o mesmo local durante um determinado período todos os anos. São doenças que podem ter implicações para as aves cativas, para a população humana que tem contato com essas aves e para os plantéis de produção. Assim, ações de vigilância, com o objetivo de detectar rapidamente determinadas doenças, representam alternativas interessantes para se fazer gestão de risco. O objetivo do presente estudo foi pesquisar a presença de agentes etiológicos selecionados na população de Cisnes Negros (Cygnus atratus), mantida nos lagos da FPZSP, visto que essa população tem contato com as seguintes aves migrantes que visitam a FPZSP todos os anos: irerês (Dendrocygna viduata), marreca caneleira (Dendrocygna bicolor) e marreca asa de seda (Amazoneta brasiliensis). Assim, foram colhidos suabes de traquéia e cloaca de uma amostra capaz de detectar doença com prevalência estimada em 1% para um nível de confiança de 95%. Além disso, foi realizado um estudo retrospectivo (2001 a 2006) das principais causas de morte nessa população. As principais causas de mortalidade registradas em 184 registros analisados foram: desvio de tendão extensor tarso-metatarsiano (37, 20,1%), desnutrição (20, 10,9%), problemas hepáticos (17, 9,2%), traumas (15, 8,2%), problemas respiratórios (8, 4,3%), septicemias (6, 3,3%), intoxicações (5, 2,7%) e problemas gastrointestinais (3, 1,6%). Um terço das carcaças (62, 33,7%) foi encontrado em estado de putrefação. A taxa de mortalidade foi decrescente de 2001 a 2006 e apresentou sazonalidade, sendo maior entre os meses de novembro a maio. No momento das coletas, não houve nenhuma evidência clínica ou laboratorial da presença dos seguintes agentes: Pasteurella multocida., Salmonella sp., Chlamydophila psittaci, Orthomixovírus (Influenza Aviária), Paramixovirus (Doença de Newcastle) e Coronavirus (Bronquite Infecciosa).<br>Waterfowls housed in ponds of zoos and parks are under constant risk of exposure to pathogens of migratory birds that visit these places every year. Some of them involving zoo animals and humans. The spread of particular diseases may also become a serious threat for domestic poultry. So, surveillance, focused in early detection of some diseases, can be an interesting tool to do risk management. The goal of the present work was to search the presence of some select pathogens in the captive black swan population (Cygnus atratus) present in the ponds of the Fundação Parque Zoológico de São Paulo (FPZSP), because these animals have contact with the following free-living waterfowls: white-faced whistling-duck (Dendrocygna viduata), fulvous whistling-duck (Dendrocygna bicolor) e brasilian teal (Amazoneta brasiliensis). Swabs of trachea and cloaca were sampled from 239 animals, the sample size required for detecting disease present in at least 1% of the animals (CI = 95%). Moreover, a retrospective study was done about the causes of death to the period from 2001 to 2006. The mainly causes of black swan death in FPZSP were: slipped tendon (37/184, 20,1%), malnutrition (20/184, 10,9%), hepatic problem (17/184, 9,2%), trauma (15/184, 8,2%), respiratory problem (8/184, 4,3%), septicemias (6/184, 3,3%), intoxication (5/184, 2,7%) e gastro-intestinal problems(3/184, 1,6%). One third of the carcass (62/184, 33,7%) was in autolysis. The mortality presented peaks of occurrence from november to may and a decreasing trend from 2001 to 2006. At the moment of the sampling, there was no clinical or laboratorial evidence of the infection by the following pathogens: Pasteurella multocida., Salmonella sp., Chlamydophila psittaci, Orthomixovírus (Avian Influenza), Paramixovirus (Newcastle Disease) e Coronavirus (Infectious Bronchitis).

Emerging influenza viruses continue to challenge public health. The problem is public health science professionals have been battling emerging human influenza diseases with tactile and reactionary methods because there is a lack of knowledge and data at the human-animal interface. This research was a baseline study of the proportion of influenza A virus (IAV) in urban and rural communities in California. The population was artificial recirculating water ponds in the geographic locations of rural and urban Californian communities. Surface water samples [N = 182] were collected from artificial recirculating ponds in California. Positivity for IAV was verified by real time RT-PCR, MDCK cells for virus infectivity, nucleotide sequencing of the RNA genome, and phylogenic analysis of IAV H5N1 strains. The proportion of IAV in rural and urban ponds favored the greater burden of IAV in urban ponds over rural ponds. The presence of waterfowl and IAV M gene sequence positivity were found not to be significantly related. The geochemical properties--pH, salinity, and water temperature at time of collection--were not predictors of IAV infectivity. This baseline research study validated these water ponds as resource sites for IAV surveillance and monitoring. The social change implications of this study can be recognized at the national and international levels, to the population level, and to the individual level by providing geospatial analysis and spatial-temporal data for IAV surveillance, initiating biosecurity measures to protect poultry industries in the United States and Brazil, and contributing to the current IAV strain library. Contributions to the IAV strain library may be used to develop vaccines against human pandemics.

Made available in DSpace on 2016-08-18T17:23:43Z (GMT). No. of bitstreams: 1 Dissertacao Daniel Rocha.pdf: 2551995 bytes, checksum: 65ba8cf188c0a50be02f159bd8286406 (MD5) Previous issue date: 2014-02-20<br>Assessment of compliance of the Program Monitoring Migratory Birds (PMMB) during deployment pier in San Luis - MA, through documents obtained from the entrepreneur and the environmental agency. It was shown in this study that several PMMB guidelines were not followed and the results showed different patterns of the studies of other authors for the same region. Therefore, the PMMB was not completed as proposed and the results of monitoring may have been committed in this sense is not possible to define the dynamics of interference in birds studied by the project.<br>Avaliação do cumprimento do Programa de Monitoramento de Aves Migratórias (PMAM) durante a implantação de píer em São Luís MA, por meio de documentos obtidos junto ao empreendedor e ao órgão ambiental. Foi evidenciado nessa pesquisa que várias diretrizes do PMAM não foram seguidas e que os resultados mostraram padrões diferentes dos estudos de outros autores, para a mesma região. Portanto, o PMAM não foi cumprido conforme proposto e os resultados dos monitoramentos podem ter ficado comprometidos, nesse sentido não é possível definir a interferência na dinâmica das aves estudadas por parte do empreendimento.

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No. of bitstreams: 1 DissBR.pdf: 1048371 bytes, checksum: a7b21c9d34f402da02fa685209276dbe (MD5) Previous issue date: 2016-10-07<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Estuaries are highly productive environments susceptible to environmental variables, and important to the life cycle of various species, to waterfowl serve as a point of rest, feeding and nesting. These sites also receive migratory birds seeking the accumulation of energy required for the return to the reproductive areas. These species, as well as residents, have their distribution, occurrence, abundance and behavior influenced by environmental variables, seasonality and human presence. Thus this study aimed to characterize the structure of the community of waterfowl, as well as behavioral pattern, relationship with environmental variables and habitat use by them in the mouths of the rivers Tijucas and Inferninho. The Tijucas’ Bay where this study was conducted, presents sediment deposition and formation of extensive muddy plans. To collect the data length of 1.1 km was covered in each mouth, from June 2015 to May 2016, sampling occurred every two hours, from 08 hours to 16 hours. The data collected were species, average number, activity and micro-habitat. five microhabitats were considered, based on different faces found in two locations, and analyzed environmental variables were: wind speed, tide height, precipitation and temperature. The curve of rarefaction and Jackknife 2 were used to determine the sample sufficiency, Shannon index was used to estimate the annual and monthly diversity and similarity among the studied areas was calculated using the Jaccard index. Analysis of Variance (ANOVA) and Kruskal-Wallis test were used to determine the differences between species richness, average number and behavior of the species for hours and months of sampling. The behavior relative frequency was grouped by similarity of Bray-Curtis, the Indicator Species Analysis was used to determine the association of species with micro-habitats, and used Canonical Correlation Analysis (CCA) to determine the correlation between the variables environmental and behavior and between species. Were recorded 44 species of waterfowl in the voices of the two rivers, 10 migratory. The similarity between the two areas was 75%, indicating high similarity of microhabitats between areas. The diversity at the mouth of the river Tijucas was higher than the mouth of the river Inferninho, this difference is related to river discharge of rivers, hence the nutrient input. The difference in species richness, abundance was significant only between the months of observation, and the months with the highest diversity occurred in the late spring, summer and early fall, probably due to the life cycle and arrival of migratory species. The rest was the most frequent activity, followed by foraging, this was negatively related to temperature variation, it suggests that the higher the temperature, the lower the foraging, avoiding waste of energy and water. Foraging was negatively correlated with the height of the tide as the low tide provides a food resource. The indicator species analysis showed that most of the species was associated with only one micro-habitats, this can be explained by the abundance of available resource, since rich environments allow specialization of species.<br>Os estuários são ambientes de elevada produtividade, suscetíveis a variáveis ambientais, e importantes para o ciclo de vida de diversas espécies, para as aves aquáticas servem como ponto de descanso, alimentação e nidificação. Esses locais ainda recebem aves migratórias que buscam o acúmulo de energia necessário para o regresso às áreas reprodutivas. Essas espécies, assim como as residentes, têm suas distribuição, ocorrência, abundância e comportamento influenciados pelas variáveis ambientais, sazonalidade e presença humana. Dessa forma esse estudo teve o objetivo de caracterizar a estrutura da comunidade de aves aquáticas, bem como padrão comportamental, relação com variáveis ambientais e uso de hábitat pelas mesmas nas fozes dos rios Tijucas e Inferninho. A Baía de Tijucas, onde esse trabalho foi realizado, apresenta deposição de sedimento e formação de extensos planos lamosos. Para coletar os dados a extensão de 1,1 km foi percorrida em cada foz, de junho de 2015 a maio de 2016, as amostragens ocorreram a cada duas horas, das 08 horas às 16 horas. Os dados coletados foram: espécie, número médio, atividade realizada e micro-habitat ocupado. Foram considerados cinco micro-hábitats, baseado nas diferentes fisionomias encontradas nos dois locais, e as variáveis ambientais analisadas foram: velocidade do vento, altura da maré, precipitação e temperatura. A curva de rarefação e Jackknife 2 foram usados para determinara a suficiência amostral, o índice de Shannon foi usado para estimar a diversidade anual e mensal, e a similaridade entre as áreas estudadas foi calculado através do índice de Jaccard. Análise de Variância (ANOVA) e teste de Kruskal-Wallis foram usados para determinar as diferenças entre riqueza, número médio e comportamento das espécies por horário e meses de amostragem. A frequência relativa de comportamentos foi agrupada pela similaridade de Bray-Curtis, a Análise de Espécie foi usada para determinar a associação das espécies com os micro-habitats, e usou-se Análise de Correlação Canônica (CCA) para determinar a correlação entre as variáveis ambientais e comportamentos e entre espécies. Foram registradas 44 espécies de aves aquáticas nas fozes dos dois rios, sendo 10 migratórias. A similaridade entre as duas áreas foi de 75%, indicando alta semelhança de micro-habitats entre as mesmas. A diversidade na foz do rio Tijucas foi maior que a foz do rio Inferninho, essa diferença está relacionada a descarga fluvial dos rios, consequentemente ao aporte de nutrientes. A diferença de riqueza, abundancia foi significativa apenas entre os meses de observação, e os meses com maiores diversidades ocorreram no final da primavera, verão e começo do outono, provavelmente devido ao ciclo de vida e chegada das espécies migratórias. O descanso foi a atividade mais frequente, seguido de forrageio, este esteve negativamente relacionada a variação de temperatura, sugere que quanto maior a temperatura, menor o forrageio, evitando dispêndio de energia e água. O forrageio esteve negativamente relacionado com a altura da maré, já que a maré baixa disponibiliza recurso alimentar. A análise de espécies indicadoras apontou que a maior parte das espécies esteve associada a apenas um micro-habitat, isso pode ser explicado pela abundância de recurso disponível, já que ambientes ricos permitem a especialização das espécies.

La gestion de la faune sauvage hors des ENP pose en premier lieu la question de la connaissance des milieux qu'elle fréquente et de l'évolution de leur capacité d’accueil. Aboutir à une description détaillée de la répartition qualitative et quantitative des espèces, avec comme seuls collecteurs de données des professionnels formés à ces fins, peut sembler utopique. L’immensité des espaces de la campagne banale combinée à la mobilité des espèces supposent une présence régulière et un relevé assez fréquent d'indices de présence lorsque des suivis sont nécessaires. Si certains chercheurs et gestionnaires n’hésitent désormais plus à utiliser l’écologie participative comme un moyen de collecte de ces données, cette méthode souffre parfois d’un manque de bénévoles, donc d'un défaut d’informations sur certaines parties des maillages qu'il faudrait renseigner. Dans ce contexte, envisager de solliciter ceux qui façonnent ces milieux naturels, donc qui séjournent longuement et utilisent cette nature, semble une alternative plausible pour acquérir des informations et des savoirs nécessaires à la gestion de la faune sauvage. Or, la qualité de ceux-ci est à interroger pour en mesurer la richesse et la fiabilité, et donc les possibilités ou non de les mobiliser dans des processus de suivis ou de gestion. Afin de conduire cette recherche, un objet et un terrain d’étude appropriés étaient nécessaires. Le choix s’est porté sur les savoirs locaux des chasseurs de gibier d’eau des zones humides girondines. La pratique de la chasse de la nuit a été plus particulièrement ciblée, ces adeptes disposant de carnets sur lesquels ils enregistrent parfois depuis longtemps des observations de l’avifaune, et l’activité en elle-même imposant de se tenir dans un poste fixe. Au-delà de leurs observations, des savoirs locaux potentiellement importants ont donc pu être accumulées. Dans les deux cas, l’accès à ces items est complexe et impose de créer une relation de confiance, que nous avons acquise grâce à l’échange d’informations. Il a ainsi été possible de poursuivre notre recherche en nous intéressant à l’aspect « observations » grâce aux carnets, puis à l’aspect « savoirs » en menant des entretiens en situation avec ces locaux. Notre travail interroge d’abord à la nature des informations nécessaires à la gestion de différentes espèces de la faune sauvage, et à la variabilité des moyens qui sont utilisés pour les collecter. La mobilisation de savoirs appartenant parfois à des ruraux amène ensuite à s’interroger sur leur pertinence scientifique. Il apparaît que ces derniers peuvent s’avérer être des contributions probantes qui concourent à une meilleure gestion de la faune sauvage. Ainsi, on montre ensuite en quoi différentes pratiques cynégétiques mobilisent des savoirs qui semblent pouvoir contribuer à la gestion de la faune sauvage. Les caractéristiques de la chasse de nuit au gibier d’eau la rendent plus propice à la collecte d’observations et de savoirs originaux, dont certains pourraient contribuer à la gestion de l’avifaune migratrice. Les zones humides girondines apparaissent alors comme un terrain d’étude approprié. Puis, on regarde de manière détaillée en quoi consiste la pratique de la chasse au gibier, et on montre que ces pratiquants sont susceptibles de collecter des informations originales sur l’avifaune et les milieux humides. La fiabilité des informations collectées et donc la qualité des observateurs pouvant être hétérogènes suivant les affinités de ces pratiquants, les meilleurs d’entre eux doivent être identifiés. On s’attache alors à déceler, en utilisant leurs carnets, les chasseurs qui, parmi la masse de ces individus, s’avèrent être des observateurs fiables. Au-delà, les informations qu’ils ont accumulées sont susceptibles de s’être combinées en savoirs. A travers une série d’entretiens puis d’évaluations, c’est la nature et la richesse de leurs savoirs qu’on interroge, pour identifier les plus experts et compétents d’entre eux<br>The wildlife management outside the protected natural area asks the question of knowledge of the environments it attends and the evolution of their capacity. Achieve to a detailed description of the qualitative and quantitative distribution of species, with the only professionals as data collectors trained for these purposes, seems Utopian. The immensity of spaces of trivial campaign combined with the mobility of species involved a regular presence and a fairly common statement for presence indices when monitoring is necessary. While some researchers and managers are now more reluctant to use the participatory ecology as a way of collecting these data, this method can sometimes suffer from a lack of volunteers. A lack of information can exist on some parts that it would inquire. In this context, consider seeking those who shape these natural environments, staying long and using this nature seems a plausible alternative to acquire information and knowledge necessary to wildlife management. But the quality of these collectors is to ask to measure wealth and reliability, and thus the opportunities or not to engage in follow-ups or management process. To conduct this research, an object and a field of appropriate study were required. The choice fell on local knowledge of waterfowl hunters of the Gironde wetlands. The practice of hunting at night was particularly targeted, these enthusiasts have books on which they sometimes long record observations of birds, and the activity itself imposing to stand in a fixed position. Beyond their observations, potentially significant local knowledge could therefore be accumulated. In both cases, access to these items is complex and requires to create a relationship of trust that we have gained through the exchange of information. It was thus possible to continue our research by focusing on the aspect of "observations" through books, and then to the aspect of "knowledge" by conducting interviews with these locals hunters. Our work first examines the nature of the information necessary for the management of different species of wildlife and variability wherewithal that are used to collect. The mobilization of knowledge sometimes belonging to rural then raises questions about their scientific relevance. It appears that these may contribute to better management of wildlife. Thus, we show how various hunting practices mobilize knowledge that appear to contribute to the management of wildlife. The characteristics of the night hunting waterfowl make it more conducive to the collection of observations and original knowledge, some of which could contribute to the management of migratory birds. Wetlands Gironde appear as an appropriate field study. Then, we look in details what constitutes the practice of hunting game, and show that these practitioners are likely to collect original information on birds and wetlands. The reliability of information collected and therefore the quality of the observers may be heterogeneous according to the affinities of these practitioners, the best of them should be identified. The last part then attaches to detect, using their notebooks, hunters who among the mass of these individuals turn out to be reliable observers. In addition, the information they are likely to have accumulated combined knowledge. Through a series of interviews and evaluations, it is the nature and the richness of their knowledge that asks to identify the most expert and competent of them

Several factors have contributed to impeding the progress of migratory waterfowl spatial modeling, such as (1) waterfowl’s reliance on wetlands, (2) lack of understanding about shifts in distributions through time, and (3) large-scale seasonal migration. This doctoral dissertation provides an array of tools to address each of these concerns in order to better understand and conserve this group of species. The second chapter of this dissertation addresses issues of modeling species dependent on wetlands, a dynamic and often ephemeral habitat type. Correlation models of the relationships between climatic variables and species occurrence will not capture the full habitat constraints of waterfowl. This study introduces a novel data source that explicitly models the depth to water table, which is a simulated long-term measure of the point where climate and geological/topographic water fluxes balance. The inclusion of the depth to water table data contributes significantly to the ability to predict species probability of occurrence. Furthermore, this data source provides advantages over traditional proxies for wetland habitat, because it is not a static measure of wetland location, and is not biased by sampling method. Utilizing the long-term banding bird data again, the third chapter examines the behavior of waterfowl niche selection through time. By using the methods developed in chapter two, probability of occurrence models for the 1950s and the 1990s were developed. It was then possible to detect movements in geographic and environmental space, and how movements in these two spaces are related. This type of analysis provides insight into how different bird species might respond to environment changes and potentially improve climate change forecasts. The final chapter presents a new method for predicting the migratory movement of waterfowl. The method incorporates not only the environmental constraints of stopover habitat, but also includes likely distance and bearing traveled from a source point. This approach uses the USGS’ banding bird database; more specifically, it relies on banding locations, which have multiple recoveries within short time periods. Models made from these banding locations create a framework of migration movement, and allow for predictions to be made from locations where no banding/recovery data are available.<br>text

"Seeking Refuge" examines the history of migratory waterfowl management along the Pacific Flyway, the westernmost of four main migration routes in North America. Drawing on approaches from historical geography and environmental history, this study shows how wildlife officials developed migratory bird refuges in Oregon and California, where over 60 percent of Pacific Flyway waterfowl winter. During the early-twentieth century, reclamation and river diking eliminated most of the wetlands in the birds' wintering range. Bird enthusiasts such as bird watchers and duck hunters successfully lobbied for the creation of wildlife refuges in a few areas along the flyway. These early refuges failed to protect waterfowl habitat and they were severely degraded by reclamation. In the 1930s and 1940s, the U.S. Fish and Wildlife Service (FWS) and its predecessor, the Bureau of Biological Survey, undertook an ambitious program to resurrect these sanctuaries and to create new ones. Many farmers opposed these refuges out of fear that waterfowl would damage crops. To respond to these concerns and to ensure an adequate food supply for the birds, the FWS raised rice, barley, and other crops. The agency adopted many of the technologies of modern, industrial agriculture including synthetic herbicides and insecticides such as 2, 4-D and DDT. By the 1960s, the refuges had become largely mirrors of the surrounding irrigated farmlands, the main difference being that the FWS raised grain for waterfowl rather than for market. Refuges could not escape the agricultural settings in which they were embedded. As units within the irrigated countryside, Pacific Flyway refuges were often at the mercy of nearby farmers and federal reclamation agencies. Poor water quality and insufficient supplies of water often hampered FWS efforts to manage refuges. In the late-twentieth century, reduced water supply due to diversions to California municipalities and to sustain endangered fish species affected the amount of water reaching refuges. This dissertation has other goals. First, it critiques the anthropocentrism of most historical geography by focusing on how political, cultural, and ecological factors affected wildlife. Second, it contributes to the literature on the state's role in environmental protection by investigating the overlapping, and often contradictory, spaces within which wildlife managers implemented environmental regulations.

Mute swans (Cygnus olor) are an invasive species originally brought to the United States in the late 19th and early 20th centuries for ornamental ponds and lakes, zoos and aviculture collections. Original populations were located in northeastern states along the Hudson Valley but have since expanded to several Midwestern states and portions of the western U.S. and Canada. Mute swan damage includes competing with native waterfowl, destroying native plants, spreading disease, and colliding with aircraft. They are also considered a nuisance in some areas due to their abundant fecal droppings and aggressiveness towards people. Some have questioned the status of mute swans as an introduced species, but multiple reviews by scientists and the U.S. Fish and Wildlife Service clearly support the conclusion that mute swans are not native to North America. The Migratory Bird Treaty Act, therefore, does not protect mute swans, and management authority falls under jurisdiction of the states and Tribes.