<p> The United States Fish and Wildlife service declared an unusual mortality event (UME) in 2006 when a high number of northern sea otters in Alaska were found dead beginning in 2002. Necropsies revealed the cause of death in 30% of cases to be septicemia with meningoencephalitis and/or vegetative valvular endocarditis (VVE) colonized by gram positive cocci, later determined to be primarily <i>Streptococcus infantarius</i> ss <i>coli</i> and <i>Streptococcus phocae</i>. While much work has been done to uncover the pathogenic agents responsible for these deaths in northern sea otters, the ecology of <i>S. infantarius</i> ss <i>coli</i> and <i>S. phocae</i> in the environment remains poorly understood. This study investigated the presence of <i>S. infantarius</i> ss <i> coli</i> and <i>S. phocae</i> in the marine environment by 1) developing a molecular method to detect <i>S. infantarius</i> ss <i>coli</i> 2) examining potential microbe-habitat associations in Kachemak Bay and Resurrection Bay, Alaska, and 3) determining the competency of otter prey species to act as reservoirs for these pathogens. A PCR assay was developed to detect the <i>sodA</i> gene of <i> S. infantarius</i> ss <i>coli</i> in both environmental and clinical samples. Water and bay mussels were collected from sites in Kachemak and Resurrection Bays and pathogen presence was determined using PCR. Habitat attributes were recorded onsite and determined using ShoreZone. Prey competency was determined via a dosing experiment in the lab. Our primer set for the <i> S. infantarius</i> ss <i>coli</i> <i>sodA</i> gene, as well as a previously published primer set for the <i>S. phocae</i> <i> sodA</i> gene, successfully identified our targets in clinical and environmental samples using conventional PCR. Primer sets we designed successfully quantified the <i>sodA</i> gene of <i>S. infantarius</i> ss <i> coli</i> and/or <i>S. phocae</i> in environmental samples and in dosed prey samples using qPCR. <i>S. infantarius</i> ss <i> coli</i> and/or <i>S. phocae</i> were present in water or mussels at 61 of 162 sites. Statistical analyses to determine bacterial correlations with habitat attributes revealed some correlations between habitat parameters selected and presence of our target bacteria in the environment. Prey competency experiments showed that bivalves were the most competent pathogen reservoirs. Results of this study will inform microbial ecologists and wildlife managers of the potential environmental risk factors for <i>S. infantarius</i> ss <i>coli</i> and <i>S. phocae</i> infection as well as provide information about pathogenic bacterial presence in the marine environment. </p><p>

<p> Unregulated hunting and habitat loss led to a near extirpation of moose (Alces alces) in New Hampshire in the 1800s. After state protection in 1901, the estimated population increased slowly to &sim;500 moose in 1977, then increased rapidly in the next 2 decades to &sim;7500 following an increase in browse habitat created by spruce budworm (<i>Choristoneura fumiferana </i>) and related timber salvage operations, and then halved from 1998-2016 despite highly available optimal habitat. The declining population was partially related to the specific management objective to reduce moose-vehicle collisions, and a possible change in deer hunter and moose behavior that influence population estimates. But given the substantial decline in productivity and condition of cows, and frequent episodes of high calf mortality in April, the primary cause of decline was presumed to be is an increase in winter tick abundance. </p><p> This study examined the relationships among moose density, optimal habitat, weather/ground conditions, winter tick abundance, and natal dispersal in northern New England. Comparing movement data from the previous (2002-2006) and current (2014-2016) productivity studies in New Hampshire and Maine, the distance of natal dispersal, home and core range size, and home and core range overlap did not significantly (<i>P</i> > 0.05) change despite an increase in optimal habitat and a decrease in moose density.</p><p> Geographic changes in tick abundance were related to an interaction between moose density, and the onset and length of winter. Annual changes in tick abundance in northern New Hampshire are driven by desiccating late summer conditions, as well as the length of the fall questing season. Lower precipitation (6.4 cm) and higher minimum temperatures (9.8 &deg;C) specifically concentrated during larval quiescence from mid-August through mid-September reduces winter tick abundance and the likelihood of an epizootic event. The onset of winter, defined by the first snowfall event (> 2.54 cm), influenced the length of the questing season relative to the date of long-term first snowfall event (14 November). In the epizootic region, average winter tick abundance on moose harvested in mid-October indicated a threshold of 36.9 ticks, above which an epizootic is like to occur unless an early snowfall event shortened the fall questing season. Optimal habitat created by forest harvesting was produced at an annual rate of 1.3% (1999-2011) and is not considered limiting in northern New Hampshire, but likely concentrates moose density locally (&sim;4 moose/km²) facilitating the exchange of winter ticks. In northern New Hampshire, snow cover late into April did not reduce tick abundance in the following year and cold temperatures (&lt; 17 &deg;C) that induced replete adult female mortality are extremely rare in April.</p><p> Given a continuation of warming climate and conservative moose harvest weather conditions and high local moose densities will continue to favor the life cycle of winter ticks, increasing the frequency of winter tick epizootics and shift the epizootic region slowly northward. Conversely, temporary reduction of moose density may substantially reduce parasite abundance and support a healthier and more productive moose population.</p><p>

<p> The Rusty Blackbird (Euphagus carolinus) is a migratory songbird that breeds in and near the boreal wetlands of northern New England and Canada. Although the Rusty Blackbird was once common, the species has declined by an estimated 90% since the 1960&rsquo;s (Greenberg et al. 2010). I used single-season occupancy analysis to model breeding Rusty Blackbirds&rsquo; use of 60 beaver (Castor canadensis) influenced wetlands in Coos County, New Hampshire and Oxford County, Maine. I conducted three 30 minute detected/ not detected surveys, surveyed food availability and foraging habitat, and digitized each survey wetland. Rusty Blackbirds&rsquo; use of wetlands was best predicted by the site covariates mud and invertebrate abundance and detectability was best predicted by survey period. Probability of wetland use decreased with increasing mud cover and increased with increasing aquatic invertebrate abundance. I recommend that future researchers survey for Rusty Blackbirds for 30 minute periods to maximize survey coverage.</p><p>

Reintroduction is a potentially powerful tool available to conservationists to cope with species population declines. Nonetheless, it is poorly understood and past reviews tend to indicate poor results. Reintroduction, under the sensu stricto IUCN definition, must have a primary objective of conservation; however species can be released to sites in their indigenous range (reintroduction sensu lato) to meet other objectives. The outcomes of these reintroductions s.l need to be assessed to determine how effectively they achieve their varied objectives. A Web of Science review revealed that only 32.1% of 131 publications on reintroduction provided clearly defined success criteria. Using economic, ecological, conservation and problem animal management objectives as reintroduction s.l. drivers, I developed context-dependent success definitions for each objective to use in reintroduction outcome assessments. These success criteria were then used to assess the reintroductions s.l. of large carnivores, namely lion, leopard, cheetah, African wild dog, spotted hyaena, and brown hyaena, to 16 private- and state-owned reserves in the Eastern Cape Province, South Africa. Ecotourism and ecological restoration were the most common objectives for the reintroduction of top predators to these reserves. Overall the reintroductions of large carnivores have been successful in meeting their objectives. Only African wild dogs have failed to establish in the province. Causes of objective-specific failures for the other species in some reserves included introductions of same-sex populations, lack of breeding events and changes in reserve management objectives. Assessments for leopard and brown hyaena were inconclusive due to lack of monitoring data. The reintroduction of large carnivores to the Eastern Cape Province has also resulted in the emergence of human-carnivore conflict on neighbouring properties. Carnivores have reportedly escaped from 8 reserves (61.5% of reserves) in the Eastern Cape. A total of 75 conflict events on 68 neighbouring properties (36.7% of neighbouring properties) have been reported. There is a major gap in research around conflict resulting from carnivore reintroductions and future research is required to fully understand the situation in the province in order to develop effective mitigation methods. An adaptive management approach to reintroductions is encouraged to improve monitoring and ensure reintroductions continue to meet their objectives. Furthermore, emerging consequences, such as human-wildlife conflict, and related mitigation strategies should be incorporated into management of reintroduced populations. Communities surrounding reintroduction sites should be educated on lifting baselines where conflict-causing species are recovering to ensure continued success of reintroduction undertakings. National management plans should be developed for all large carnivore species to improve the conservation value of small, fenced reserves that are typical of South African conservation, through a managed metapopulation approach. Management plans should include social, political, and economic factors that can influence the success of reintroductions and ultimate conservation outcomes.

<p> Lyme disease is the most common infectious disease spread by black-legged ticks in the Northern Hemisphere. Lyme disease is a vector-borne zoonotic disease typically caused by bacterial spirochetes of the species Borrelia burgdorferi. The primary vector of Lyme disease in the Midwestern and eastern United States is <i>Ixodes scapularis</i>, the deer or black-legged tick. Although there are several preventative measures against ticks that carry Lyme disease, such as public education regarding personal protection (e.g., wearing light colored clothing, tucking pants into socks, wearing repellent, promptly inspecting oneself to remove ticks, getting pets vaccinated) and recommended control measures, it is important to understand how the disease is transmitted and which factors increase the potential risk of contracting the disease. Even with these preventative measures, which are not necessarily available worldwide, tick-borne diseases are increasing both in numbers and impact to the overall human population, and there are still several knowledge gaps and conflicting findings that need to be elucidated. For these reasons, there exists a need for further research on Lyme disease ecology to identify steps necessary to decrease disease prevalence and reduce human exposure. I conducted a field study on the Cantonment Area of Fort Drum Military Installation, New York, which is representative of a suburban community with multiple cover types. From May 2015&ndash;November 2016 I surveyed the Cantonment Area to evaluate the basic distributions of <i>Ixodes scapularis </i> and small mammal host species, their relationships with vegetative characteristics, and associated Lyme disease apparent prevalence. This will allow resource managers to assess and communicate the likelihood of encountering a Lyme-positive tick and to take necessary actions to minimize that risk. Specifically, our objective was to assess the apparent prevalence of Lyme disease based on the distributions and indice of abundance of the vector and host populations on Fort Drum. </p><p> I used tick drags to evaluate black-legged tick temporal and spatial distributions in six different cover types discriminated by developmental stage. Total index of tick abundance was related to (1) temperature, (2) humidity, (3) coarse woody debris, (4) leaf litter depth, (5) tree species richness (6) average tree dbh, and (7) patch size. Adult index of abundance was greatest in the spring and fall, while nymph index of abundance was greatest in early summer and larval index of abundance was greatest at the end of summer. Tick and Lyme-positive tick indices of abundance were greatest in the coniferous and mixed cover type and lowest in the shrub and deciduous cover type. Overall Lyme disease apparent prevalence on the Cantonment Area of Fort Drum was 35% (434/1246). These results provide objective criteria for understanding a baseline of tick distributions on a temporal and spatial scale, and assist in developing management recommendations to decrease Lyme disease apparent prevalence on the landscape. </p><p> I used Sherman and Tomahawk traps to capture individuals from the overall small mammal host community during June&ndash;August. The small mammal community was composed mostly of <i>Peromyscus</i> sp. (n = 79; 38%), chipmunk (n = 59; 28%), red squirrel (n = 33; 16%), gray squirrel (n = 18; 9%). Trapping success, as well as Simpson&rsquo;s and Shannon&rsquo;s indices of diversity were greatest in the developed and coniferous forest cover types. Indices of abundance of small mammals were greatest in the developed cover type, followed by coniferous forest. We modeled the relation between estimated index of abundance of ticks with the estimated index of abundance of all small mammal host species, as well as the relationship between estimated index of abundance of Lyme-positive ticks and small mammal host Simpson&rsquo;s and Shannon&rsquo;s indices of diversity. Although <i>Peromyscus</i> sp. had a greater number of individuals with tick burdens, there was significantly greater estimated index of abundance of Lyme-positive tick burdens on chipmunks. Furthermore, a significantly greater proportion of sampled chipmunks (58%) had Lyme-positive ear punches. </p><p> My results suggest that habitat management in the coniferous and mixed forest that target vector and host habitat is necessary in order to decrease Lyme disease prevalence and reduce risk of human exposure. Recommendations such as removal of the leaf/pine litter and coarse woody debris, which provide stable microhabitat for ticks and small mammals alike, a selective cut of large conifer trees, allowing sunlight and wind penetration that encourages tick desiccation, and creating and mowing grassland barrier habitat between human developed areas and forested areas are possible solutions for decreasing Lyme disease prevalence and human risk of exposure on the landscape. Public education seminars regarding black-legged tick spatial and temporal distributions, as well as explaining recommended control measures for personal property should also be developed in order to communicate Lyme disease risk to residents on Fort Drum Military Installation.</p><p>

The purpose of this thesis is to explain the spatial diffusion of lead in the forest vegetation along highway 417, around Limoges, Ontario. The analyses of samples taken along both sides of the highway 417 tells us that the wind is the main carrier of particulate lead. Knowing that the predominant winds are from WNW, we conclude that there is a greater concentration of lead north-east of the highway where most of the emanations fall. Lead particles that are carried by the winds settle on the tree foliage and are absorbed in very small quantities by the leaves stomates. The concentration of lead on foliage diminishes gradually with distance from the highway and distilled water will not wash it off. Lead also appears on the tree trunks. There again, the concentration is found to diminish with distance from the highway. The study also reveals that there is no correlation between the concentration of lead on the outside of the tree barks and the inside. Actually, this study cannot explain this phenomenon. (Abstract shortened by UMI.)

Variation in feeding behaviour was studied among young individuals of pumpkinseed (Lepomis gibbosus) and yellow perch (Perca flavescens). Three types of food, Drosophila, Daphnia and Artemia were used for the experiments. Eight individuals of pumpkinseed differed significantly in their number of feeding attempts, in time interval between feeding attempts (in the beginning, middle and towards the end of the experiment), feeding angle, number of unsuccessful attempts and regurgitations. Most of the differences in the time interval between feeding attempts were observed in the middle and towards the end of the experiment. When the experimental diet was composed of three types of foods (Drosophila, Daphnia and Artemia) in a mixture, the total number of feeding attempts in the experiment decreased. Mixing the food types also reduced the feeding efficiency of individuals which was evidenced by the increased time interval between the feeding attempts and the increased unsuccessful attempts and regurgitations. Individuals of pumpkinseed showed the highest preference for Daphnia. On the basis of the above feeding variables, groups of individuals of differing feeding patterns were identified. Similar patterns were observed for the eight individuals of yellow perch. Perch fed more efficiently on Artemia, however, two individuals of perch were more efficient on feeding on Daphnia. Effects of the presence of conspecifics and increasing population density were examined on the variation among individuals of the pumpkinseed and yellow perch, for two types of food, (Daphnia and Artemia), separately and in a mixture. The effects of conspecifics were not equal on each individual of pumpkinseed and yellow perch. Only the weaker individuals were affected more by the presence of other conspecifics than the stronger ones. The increasing population density of conspecifics increased the variation among the individuals of both species. The effect of the presence of heterospecifics (yellow perch) were also examined on individuals of pumpkinseed for similar food types and feeding variables. At low experimental densities the effects of the heterospecifics were not significant. However, at high densities yellow perch affected the feeding behaviour of pumpkinseed individuals significantly. The effects of conspecifics on pumpkinseed were always greater than heterospecifics. Yellow perch did not affect the feeding behaviour of all the individuals of pumpkinseed equally.

In this thesis, the environmental values of Canada and Sweden as they are embodied in the forest policy of these two countries are examined within the framework of Beck's theory of the risk society to discover whether there is evidence to support Beck's theory of the evolution of industrialised countries from primary to reflexive modernisation. The historical, cultural and social-structural conditions underlying the development of Canadian and Swedish forest policy are also investigated in order to situate those policies in their historical and comparative context.

This study provides detailed descriptions of 149 stands of the least disturbed, most mature forest communities in the Ottawa, Ontario region. For each of these sampled communities, a complete summary is provided of tree population structure, coverage and constancy of all vascular understory species and habitat data including topographic position, drainage class, and soil characteristics. Six widespread and five locally-distributed forest alliances, comprising 21 forest associations, are defined and described on the basis of presently-dominant tree species. A dichotomous key to the associations is provided. The successional trends exhibited by the present associations are integrated into a flowchart based on tree population structures, tree ages and habitat characteristics. A discussion of succession and climax theory, terminology, variability within and between associations, environmental controls and disturbance factors is provided with emphasis on comparisons with previous investigations in eastern North America.

Abstract not available.