Browsing by Subject "habitat"

Now showing 1 - 11 of 11
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    A Survey About Aquarium, Outdoor Pond, and Water Garden Issues: Results and Technical Report.
    (Minnesota Center for Survey Research (MCSR), 2005) Minnesota Center for Survey Research
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    Assessing Calf Survival and the Quantitative Impact of Reproductive Success on the Declining Moose (Alces alces) Population in Northeastern Minnesota
    (2017-08) Severud, William
    Ungulate reproductive success is an important driver of population performance. Long-term, the northeastern Minnesota moose (Alces alces) population declined 58% since 2006, yet aerial survey estimates indicate stability during 2012–2017. Because causal mechanisms for this decline were largely unknown, I investigated calf production, survival and cause-specific mortality of calves of global positioning system (GPS)-collared dams of this population. Global positioning system collars have been deployed on adult moose and other ungulates to study various aspects of their ecology, but until the current study they had not been fitted to moose neonates. In 2013 and 2014, I GPS-collared 54 neonates and monitored them for survival. In 2015, I monitored 50 calving dams for signs of neonatal mortality using behavioral cues, and assessed seasonal calf survival with aerial surveys. In 2013 and 2014, collared calf survival to 9 months was 0.34 (95% CI = 0.23–0.52), whereas uncollared calf survival in 2015 was estimated at 0.40 (95% CI = 0.30–0.54). Survival in all 3 years dropped dramatically in the first 50 days of life; hazard peaked at about 15 days of age when dams and calves departed calving sites. Predation was the leading cause of death of collared calves (84% of mortalities); wolf (Canis lupus) predation accounted for 77% of deaths. The cumulative probability of succumbing to all forms of mortality by 9 months of age was 69.8%. I documented higher wolf predation than other recent studies with similar predator communities. Habitat use during calving and the energetically demanding post-parturition period can be an important determinant of neonatal survival. I surveyed and compared habitat characteristics of pre-calving, calving, peak-lactation, and mortality sites at a fine and broad scale. I also compared mortality sites of calves killed by wolves versus other causes, as well as calving sites of cows that successfully reared a calf to winter to those that did not. Cows tended to move to areas of more conifer forest cover to calve. During peak-lactation, cows and their calves used steeper areas with abundant forage, high concealment, and less conifer cover. Mortality sites were more level than other site types. Generally, wolf-kill sites were farther from roads. Cows that successfully reared a calf to winter typically calved in areas with more deciduous forest and less forested wetland cover than cows whose calves died. I estimated population growth rate (λ) using adult survival and calf recruitment data from the Minnesota Department of Natural Resources demographic studies and the Recruitment-Mortality (R-M) Equation, and compared this estimate to those calculated using data from the annual aerial survey. Measures of recruitment were similar whether derived from the survey or collaring studies, but generally were higher in the collared sample. More recent calculations of λ (derived from the survey [2012–2017 stabilization; 1.02 ± 0.16 (SE)] and using the R-M Equation [1.04 ± 0.04]) indicated growth over the next 50 years. However, the stochastic model using parameters from the adult and calf studies indicated an average decline in the population over the next 50 years (λ = 0.94 ± 0.004). Habitat improvement projects for moose should consider not only forage requirements, but also cover, slope, and road density. Identifying specific causes of calf mortality and understanding their relations to various landscape characteristics and other extrinsic factors should yield insight into mechanisms contributing to the declining moose population in northeastern Minnesota and serve as a basis for ecologically sound management responses.
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    The Breeding Ecology of Boreal Chickadees in the Red Lake Wildlife Management Area in Northern Minnesota
    (2023-08) Snow, Kara
    We examined the impacts of fragmentation on the breeding ecology of the Boreal Chickadee (Poecile hudsonicus) in the Red Lake WMA in Minnesota. Boreal Chickadees are listed as a Species in Greatest Conservation Need (SGCN), with declines attributed to habitat loss, degradation and fragmentation. We used linear mixed-effect models to examine the impacts of fragmentation on Boreal Chickadee food availability, nestling growth rates, body condition and provisioning rates. We modeled nest survival in relation to landscape, patch and nest site scale metrics of fragmentation using the program MCEstimate. We found evidence that fragmentation negatively impacts nest survival, nestling growth rates and food availability. Additionally, we elucidated the diet of nestling Boreal Chickadees by extracting DNA from fecal samples and using DNA metabarcoding techniques. We found that Boreal Chickadee nestlings are primarily being provisioned prey from the orders: Lepidoptera, Aranea and Diptera; and are likely actively selecting for Lepidoptera.
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    Bulletin No. 7. Mammals of Minnesota
    (Minnesota Geological Survey, 1892) Herrick, C.L.
    The manuscript and plates for a final report upon the mammals of Minnesota were turned over to the Survey in 1885, with the expectation that the work would be speedily issued as part of a quarto volume of the series of final reports. Circumstances with which the writer is unacquainted have delayed the publication over six years and in the meantime much work has been done in all branches of biology, and the state has been carefully surveyed by the United States agents. Much of whatever may have had any value as an original contribution to science has lapsed and much of the remainder has been rendered unnecessary by recent publication. This is especially true of bibliographical material. When, however, the publication was finally ordered and no opportunity was afforded for further field work, it seemed best to adapt the manuscript for the purpose by the omission of much which could not be edited satisfactorily under the circumstances, and, separating the more general from the technical portions, to issue these in the form of two bulletins, uniform with the series already established by the Survey. The present installment, therefore, contains the descriptive and popular portion, with such illustrations as may serve to assist the amateur. The second part will be devoted to the materials collected upon the anatomy, especially the myology and osteology of the mammals of Minnesota. C. L. HERRICK, Univ. of Cincinnati.
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    Evaluating American marten habitat quality using airborne light detection and ranging (LiDAR) data
    (2018-09) Joyce, Michael
    Understanding the factors that influence animal distribution and density is a central theme in animal ecology. For imperiled species, understanding the resources and conditions that allow animals to occupy the landscape is critical for development of effective conservation strategies. Not surprisingly, habitat selection is a common focus of wildlife research. This dissertation project focused on addressing two main challenges that limit the application of a fitness-based approach to understanding habitat selection: 1) data on fine-scale habitat resources and conditions required for the development and testing of resource- and fitness-based definitions of habitat are generally not available across entire study areas, and 2) indirect measurements of fitness (e.g., survival or reproductive success) are often not considered when assessing habitat selection patterns, in part, because of the difficulty of measuring fitness correlates for free-ranging animals with long life-spans and large home ranges. My first two chapters address the first challenge by using airborne light detection and ranging (LiDAR) data to measure fine-scale characteristics known to be selected by my focal species, American martens (Martes americana). In Chapter 1, I demonstrate that LiDAR data can be used to detect individual pieces of coarse woody debris, an important habitat component that provides martens with foraging habitat and access to the subnivean layer. In Chapter 2, I created statistical models to estimate 5 response variables relating to tree size and density and evaluated how well models will perform when imputed across the entire study area. I found that the models I created performed well when applied to new data, but that performance depended on the response variable being modeled. My last two chapters address the second challenge by evaluating how landscape and forest structure influence mortality risk for martens. In Chapter 3, I evaluated factors influencing harvest mortality risk. I found that martens living close to roads have higher harvest risk because trappers use roads to set and check traps efficiently. Consequently, distribution of roads can have a profound impact on habitat quality, which has important implications for gene flow and population structure. In Chapter 4, I used LiDAR data and classified satellite imagery to examine the role of forest structure in mediating interactions between martens and predators. I found that sites where martens were killed by predators were associated with non-forested areas including wetlands, shrublands, and young and regenerating forests. Although martens generally avoid non-forested areas that are associated with higher predation risk, martens must move near or through risky areas while moving across heterogeneous, managed landscapes.
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    Hydrologic Responses to Beaver Dam Removal in the Knife River Watershed
    (2022-09) Burgeson, Emma
    The hydrologic changes undergone during beaver dam construction and removal are profound and important to the health of aquatic organisms. The alteration of low-flows post-beaver dam removal was addressed here through a paired watershed study in the Knife River watershed on the north shore of Lake Superior, MN. Stream gages and piezometers measuring shallow groundwater levels were monitored for two summers to determine impacts of beaver dam removal on groundwater levels and volumetric discharge downstream. Water samples were taken for isotopic analysis and analyzed for differences in source-water contributions before and after beaver dam removal. A new procedure for analyzing changes to low-flow hydrology was created by combining three common methods of defining a low-flow threshold. This new procedure was used to determine the change in time each stream spent under low-flow conditions; removing the beaver dam was found to increase the amount of time spent in these conditions in all watershed pairs except one upland pair. Watershed characteristics including topography, substrate, and channel slope all played roles in controlling the amount of surface and subsurface storage in each sub-watershed. The upland watersheds comprised of low-order, low gradient, alluvial channels had significant decreases in groundwater levels post-beaver dam removal. The lower watersheds with smaller subsurface storage capacity did not have any significant differences in groundwater levels post-beaver dam removal. Patterns of groundwater contribution to the streams were also analyzed, but data were limited to snapshots in time.
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    Identifying and Interpreting Contemporary Wild Rice Habitat in Ceded Chippewa Lands of Northern Minnesota.
    (Center for Community & Regional Research, College of Liberal Arts, University of Minnesota, Duluth., 1995) Henderson, Martha L
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    Microhabitat Characteristics of Lapland Longspur, Calcarius lapponicus, Nests at Cape Churchill, Manitoba
    (2005) Boal, Clint W; Andersen, David E
    We examined microsite characteristics at 21 Lapland Longspur (Ca/carius /apponicus) nests and land cover types in which they occUlTed in Wapusk National Parle. Cape Churchill, Manitoba. Nests were located in four of six physiographic-vegetation land-cover types. Regardless of land-cover type. all but one nest was built on a pressure ridge or mound. Nests were built midway between the bottom and top of ridges or mounds with steeper slopes than was randomly available. Longspur nests had a distinctive southwest orientation (P < 0.(01). Longspurs selected nest sites that consisted of comparatively greater amounts of shrub species and lesser amounts of moss than were randomly available. Nests were generally well concealed by vegetation(mean =67.0%) and concealment was negatively associated with amount of graminoid species at the nest (P =0.0005). Our nesting habitat data may facilitate a better understanding of breeding Lapland Longspur habitat requirements, and
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    Microhabitat influence on young-of-year fish assemblages within the vegetated beds of the St. Louis River estuary
    (2017-07) Ramage, Hannah
    Coastal wetlands within the Laurentian Great Lakes provide crucial habitat for an abundance and diversity of fishes during larval and juveniles stages; however, young-of-year fish habitat association studies at the microhabitat scale are rare. Because studies at this fine scale are crucial for understanding the habitat properties that support fishes at this critical life stage, I examined larval and juvenile fish assemblage structure in relation to microhabitat variables within the St. Louis River estuary, a drowned river mouth of Lake Superior. Fish were sampled in aquatic vegetated beds throughout the estuary, across a gradient of aquatic vegetation types and densities. Canonical correspondence analysis, relating species abundances to environmental variables revealed that principally microhabitat variables, including plant species richness, depth, and aquatic plant cover explained difference in fish assemblages. In addition, I evaluated the specific habitat associations of non-native Tubenose Goby (Proterorhinus semilunaris) to provide insight on habitat overlap with native species and further invasion risk. Tubenose Goby were nearly ubiquitous (75% if study sites) and abundant (0.59 fish/m2) in the study site. Non-metric multidimensional scaling revealed that sunfish, Tadpole Madtom and Johnny Darter have the most potential for habitat overlap with Tubenose Goby. Generalized linear modelling revealed that Tubenose Goby occupied a specific microhabitat within vegetated beds consisting of dense cover and high plant species richness. Results from this microhabitat analysis at this critical life stage has potential to inform wetland management and restoration efforts within the St. Louis River estuary and other Great Lake Coastal Wetlands.
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    Minnesota National Forest Breeding Bird Monitoring Program Annual Report 1995–2022
    (University of Minnesota Duluth, 2022-12) Grinde, Alexis R; Siebers, Reid; Kolbe, Stephen; Bednar, Joshua D
    The Avian Ecology Lab at the Natural Resources Research Institute completed the 28th year of Minnesota's National Forest Breeding Bird Monitoring Program in 2022. These data have provided insight into the impacts of forest management on breeding bird populations and informed the development of management policies and conservation initiatives. This report summarizes forest bird monitoring data gathered from 1995 through 2022. Here we summarize the current status of species trends and overall trends for migration, habitat, and nesting guilds. We focus our discussion on species of conservation importance in the state to provide an ecological context and discuss management implications of the observed patterns in the region for these species.