Breeding Bird Populations in a Proposed Wetland Treatment Area of Northern Minnesota

A census of breeding bird populations was taken in a 40- hectare wetland near Biwabik, Minnesota, prior to the use of this wetland for phosphorus removal from treated wastewater. The wetland was comprised of four distinct habitat types: shrub swamp, black ash (Fraxinus nigra) forest, open coniferous forest, and closed coniferous forest. We used a line transect (about 4 km in length) to document species composition, relative species abundance, and habitat associations of the bird community. A total of816 individuals (mean= 204) and 45 species (mean = 34) were observed during four censuses in June and July, 1985. Two distinct bird communities were present in this wetland: those associated with ombrotrophic habitats (shrub swamp and ash forest) and those present in mincrotrophic habitats (open and closed coniferous forest). The Nashville warbler ( Vermivora ruficapilla) was the most common species in the wetland and also the only species that occurred in both minerotrophic and ombrotrophic habitats. The pre-impact data collected will allow assessment of the relative impact of adding sewage effluent to this wetland and the subsequent effect on bird species and populations

Effect of Sewage Effluent on Bird Abundance and Species Composition in a Northern Minnesota Wetland

Bird abundance was monitored before (1985 and 1987) and after (1989) sewage wastewater effluent was added to a northern Minnesota wetland. Community parameters (i.e., number of individuals and species richness) varied annually, but, overall bird communities in 1985 and 1989 were more similar to each other than they were to the 1987 community. Relative abundance of 35 bird species was unchanged between years and species abundance ranks were not different between years. Distribution of numbers of individuals (relative percent) within nesting and foraging guilds (species that have similar nesting or feeding requirements) was similar among years. Numbers of species that increased or decreased between years was independent of nesting or foraging location (e.g., ground or above ground). Overall, no differences were detected in the bird community that could be attributed to addition of sewage effluent to the wetland up to two years after treatment (1987 to 1989)

Natural Resources Research Institute Technical Report

Each autumn, millions of birds migrate from their breeding grounds in the northern hemisphere to wintering areas in the continental United States, Mexico, Central America, and South America (Rich 2004, Bildstein 2006). The North Shore Highlands parallels the Lake Superior shoreline from Duluth through Grand Portage, Minnesota to the US border with Canada. This region’s prominent ridgelines and Lake Superior coastline funnel migrating birds into this migration corridor (Hofslund 1966, Mueller and Berger 1967, Bildstein 2006). As a result, the North Shore Highlands hosts the largest migratory route for birds of prey in Minnesota and is among the highest in the US. In addition, recent data suggest that the numbers of non-raptor bird species moving along the north shore of Lake Superior are orders of magnitude larger than those for raptors. Migration periods constitute a critical life-stage for these birds as mortality rates may be higher during migration than during breeding or over wintering periods (Sillett and Holmes 2002, Smith and Moore 2003). Large bodies of water and other major topographical features cause a nonrandom distribution of migrating birds on the landscape in both periods of active flight and rest (Goodrich and Smith 2008). Landscape features that define the North Shore Highlands (Lake Superior, ridgelines, river valleys) result in a major congregation of migratory birds (raptors and passerines) that are both actively flying and resting within the region. With the current emphasis on renewable energy (Great Lakes Commission 2011), the North Shore Highlands region has become a focal point for potential wind power, with many plans already in progress (Mageau et al. 2008). Besides wind turbines there is also increased activity in the development of communication towers in the region. The North Shore Highlands region is recognized as one of the top tourist destinations in Minnesota and the upper Midwestern US. Over the past twenty years, the area has experienced increased developmental pressure from recreation, tourism, and exurban housing (MNDNR 2006). Conservation strategies aimed at the protection of migratory birds are incomplete without the focus on migratory bird flyway and stopover habitat preservation (Petit 2000, Mehlman et al. 2005). To develop conservation strategies to protect en route migratory birds within this region, there is a need to understand the cues by which migrants choose migratory flight paths and stopover habitats (Ewert et al. 2011, Buler et al. 2007, Bonter et al. 2009). Our overall goal is to provide data and mapping products that will contribute to a comprehensive conservation plan for migratory birds highlighting the potential risks of wind energy development within the North Shore Highlands region. We have worked closely with several community groups in the region (e.g., Grand Portage Indian Reservation, Cook County Local Energy Project, and Lutsen Mountains Resort) who have expressed an interest in wind energy development. Our purpose will be to eliminate or minimize interactions with migratory birds if wind turbines are placed in the North Shore Highlands region

Effects of Two (Diptera: Culicidae) Mosquito Control Agents on Growth and Reproduction of Red-Winged Blackbirds (Agelaius phoeniceus)

We compared red-winged blackbird (Agelaius phoeniceus) reproductive success and nestling growth in 1988 in 10 wetland site treated with methoprene and 10 sites treated with Bacillus thuringiensis israelensis (Bti) to 30 sites that had never received any mosquito (Diptera: culicidae) control treatment. No differences were detected between reference and treatment sites for clutch size, egg volume, growth rates, or fledge weight. The probability that an egg survived to the nestling stage was greater in methoprene-treated than reference sites. No other differences were detected among sites for reproductive success estimated using the Mayfield method. We conclude that treatment of the wetlands with methoprene or Bti did not directly or indirectly affect red-winged blackbird growth or reproduction within the first two years after treatment

On The Finite Temperature Chern-Simons Coefficient

We compute the exact finite temperature effective action in a 0+1-dimensional field theory containing a topological Chern-Simons term, which has many features in common with 2+1-dimensional Chern-Simons theories. This exact result explains the origin and meaning of puzzling temperature dependent coefficients found in various naive perturbative computations in the higher dimensional models.Comment: 11 pages LaTeX; no figure

Breeding Bird Communities Across an Upland Disturbance Gradient in the Western Lake Superior Region

The coastal region of western Lake Superior to examine relationships to human land use. Eighty-four species were detected and 50 were abundant enough to be included in data analysis. Monotonic quadratic regression models were constructed for these 50 species by using species counts as the dependent variable and the proportion of human conversion of the landscape (residential, agriculture, and commercial/industrial land uses) within each study area as the independent variable. Twenty-seven bird species had significant regressions (P < 0.05), 18 of which generally avoided areas developed by humans and 9 of which were attracted to development. De-trended correspondence analysis using counts of these 27 bird species was used to investigate multivariate, community responses to development. The first DCA axis was interpreted as a gradient from urban avoiding to urban exploiting bird species and was strongly correlated with land cover variables related to human development. Our results advance the idea that breeding bird communities can be used as indicators of ecological condition and can diagnose potential causes for changes in these conditions. Further, our study points out the usefulness of bird monitoring data in regional planning efforts that incorporate goals for maintaining native biological diversity

Applicability of open rainfall data to event-scale urban rainfall-runoff modelling

Rainfall-runoff simulations in urban environments require meteorological input data with high temporal and spatial resolutions. The availability of precipitation data is constantly increasing due to the shift towards more open data sharing. However, the applicability of such data for urban runoff assessments is often unknown. Here, the feasibility of Finnish Meteorological Institute's open rain gauge and open weather radar data as input sources was studied by conducting Storm Water Management Model simulations at a very small (33.5 ha) urban catchment in Helsinki, Finland. In addition to the open data sources, data were also available from two research gauges, one of them located on-site, and from a research radar. The results confirmed the importance of local precipitation measurements for urban rainfall-runoff simulations, implying the suitability of open gauge data to be largely dictated by the gauge's distance from the catchment. Performance of open radar data with 5 min and 1 km' resolution was acceptable in terms of runoff reproduction, albeit peak flows were constantly and flow volumes often underestimated. Gauge adjustment and advection interpolation were found to improve the quality of the radar data, and at least gauge adjustment should be performed when open radar data are used. Finally, utilizing dual-polarization capabilities of radars has a potential to improve rainfall estimates for high intensity storms although more research is still needed. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe

Thermal Fluctuations of Induced Fermion Number

We analyze the phemomenon of induced fermion number at finite temperature. At finite temperature, the induced fermion number $$ is a thermal expectation value, and we compute the finite temperature fluctuations, $(\Delta N)^2=-^2$. While the zero temperature induced fermion number is topological and is a sharp observable, the finite temperature induced fermion number is generically nontopological, and is not a sharp observable. The fluctuations are due to the mixing of states inherent in any finite temperature expectation value. We analyze in detail two different cases in 1+1 dimensional field theory: fermions in a kink background, and fermions in a chiral sigma model background. At zero temperature the induced fermion numbers for these two cases are very similar, but at finite temperature they are very different. The sigma model case is generic and the induced fermion number is nontopological, but the kink case is special and the fermion number is topological, even at finite temperature. There is a simple physical interpretation of all these results in terms of the spectrum of the fermions in the relevant background, and many of the results generalize to higher dimensional models.Comment: 17 pgs, 9 figs, RevTex

Inhomogeneous Condensates in Planar QED

We study the formation of vacuum condensates in $2+1$ dimensional QED in the presence of inhomogeneous background magnetic fields. For a large class of magnetic fields, the condensate is shown to be proportional to the inhomogeneous magnetic field, in the large flux limit. This may be viewed as a {\it local} form of the {\it integrated} degeneracy-flux relation of Aharonov and Casher.Comment: 13 pp, LaTeX, no figures; to appear in Phys. Rev.