Browsing by Subject "Conservation Biology"

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Assessment of residents' social and economic Wellbeing in conservation resettlement: a case study of Padampur, Chitwan National Park, Nepal.
(2011-12) Dhakal, Narayan P.
Conservation resettlement is a controversial issue in balancing biological conservation with the people’s social and economic needs. Very few studies have examined the conservation resettlement outcome, and majority of them view resettlement as counterintuitive to the people’s livelihood in the name of biological conservation. This thesis focuses on residents’ responses on social, economic and environmental consequences of a voluntary resettlement. Studies of forced resettlement during the creation and maintenance of national parks and protected areas have found negative socioeconomic consequences for human wellbeing. I investigated residents’ social and economic wellbeing following a citizeninitiated resettlement program in Padampur, Nepal. We found a difference between voluntary and forced resettlement respondents in overall satisfaction as well as evaluation of land quality and employment factors. However, there was no difference in their evaluation of land ownership, housing, physical infrastructure, health, social ties, and support services as having positive outcomes. Most respondents reported being socially and economically better off in the new location. In the future, economic status, food and nutrition, and marginalization of some groups could potentially reduce satisfaction. Residents’ post resettlement economic wellbeing is an important factor in balancing conservation and socioeconomic needs. After the resettlement, we found more residents were engaged in off-farm jobs, micro-enterprises, and physical facilities which were serving their needs. Our findings suggest that considering the following factors in resettlement planning may provide better post resettlement economic wellbeing: a) participatory and bottom up planning; b) fair compensation of physical asset; and c) provision of basic needs for water, and facilities for health and education. I emphasize the need of participatory resettlement planning models, and feel that the results have general applications to resettlement efforts. To see the biological aspects of the resettlement, I assessed the prey abundance in the evacuated area in comparison to the abundance in the park core area. I have chosen Sambar Unit (SU) as a measurement unit to assess the prey abundance. SU is significant with more prey abundance in the evacuated area than the core area of the park. Residents’ perceived biodiversity loss and gain was assessed in both locations (old and new). After the resettlement, residents’ positive perception in restoring wildlife habitat in the old site decreased pressure and decreased human wildlife conflicts. In the new site, I found increased understanding on sustainable utilization of natural resources through community forestry by reducing forest dependency. I suggest the need of periodic monitoring of post resettlement biological and socioeconomic gains to evaluate the long term viability of voluntary resettlement for conservation and residents’ better wellbeing. We suggest future conservation related resettlement consider lessons from the Padampur model.
Biological indicators of climate change: trends in fish communities and the timing of walleye spawning runs in Minnesota.
(2010-06) Schneider, Kristal N.
I conducted research on two projects to examine effects of climate change on Minnesota’s aquatic communities. I used walleye egg-take records from the Minnesota Department of Natural Resources for 12 spawning locations and historical ice-out data to determine if the timing of these events is changing. I used ice-out data instead of temperature for our analyses because historical temperature data is not available and ice-out has been previously related to climate change. Because ice-out has been previously related to climate change, I regressed the dates of first egg-take against ice-out dates to determine if the timing of walleye spawning runs could be a useful biological indicator of climate change. For the second project to determine if fish species abundances are changing in response to climate change, I used historical lake survey records for 34 lakes, each with 15 to 43 years of data, and regressed catch-per-unit-effort (CPUE) against year. I examined species distributions by regressing mean latitude against year. I regressed slopes of CPUE over time against 5 local air temperature variables to determine if changes in abundance were associated with air temperature. I also used stepwise regressions (forward and backward selection) and one-way analysis of variance (ANOVA) to determine if variability in trends could be explained by lake physical and chemical characteristics. Results were reported for 7 species with the strongest trends: Centrarchids (Micropterus salmoides, Micropterus dolomieu, and Lepomis macrochirus); Ictalurids (Ameiurus melas and Ameiurus natalis); Whitefish (Coregonus artedi and Coregonus clupaeformis).For the walleye spawning analyses I found that spawning runs and ice-out are occurring earlier in some lakes but not all. However, there was a strong relationship between first eggtake and ice-out dates, and walleye egg-take appears to provide a good biological indicator of climate change. For the lake survey analysis, centrarchid abundance in lakes was increasing over time, black bullhead abundance was decreasing, and other species were increasing in some lakes and decreasing in others. Slopes of CPUE versus year increased more quickly over time in smaller lakes and more quickly moving east across the state than in larger lakes toward the west. All species’ ranges were significantly advancing northward except smallmouth bass and whitefish. Regressions of CPUE versus air temperature showed that centrarchids are increasing in lakes as summer air temperatures increase, and whitefish are decreasing in lakes as air temperatures increase. In summary, the abundances and distributions of these 7 species over time may be responsive to climate change, and trends for species abundances may be influenced by lake characteristics. Centrarchids and bullhead may be good indicators, and thus, further research is warranted. Also, because there is a strong relationship between dates of first egg-take and ice-out, and because ice-out has previously been related to climate change, the timing of walleye spawning runs may be a useful biological indicator of climate change.
Bobcat (Lynx rufus) spatial ecology and harvest in Minnesota.
(2012-05) Kapfer, Paul Michael
The bobcat (Lynx rufus) is the most widely distributed and abundant felid in North America, whose status is primarily monitored via harvest and associated data. I used a combination of harvest and field data to investigate factors affecting spatiotemporal dynamics of bobcat harvest and spatial ecology in Minnesota. In chapter one, I investigate the socioeconomic and ecological factors that affected the number of bobcats harvested in Minnesota. Management of game animals requires understanding of factors that affect harvest levels. Although influenced by international law, bobcat management is the responsibility of state or provincial agencies, and jurisdictional environmental, ecological, and regulatory differences may alter which variables influence harvest. Consequently, our understanding of the factors driving bobcat harvest should be at a scale similar to that at which they are managed. I associated 32 years of bobcat harvest data from Minnesota with socioeconomic (e.g., pelt prices, license sales) and ecological variables (e.g., prey abundance, bobcat-specific index of winter severity) to determine what variables most strongly influenced annual bobcat harvest. I constructed candidate negative binomial generalized linear models based on an information-theoretic approach and used quasi-likelihood Akaike's Information Criterion adjusted for small sample size to assess the relative performance of each model. My best model suggested that annual bobcat harvest in Minnesota was positively related to the proportion of scent stations visited by bobcats and season length, and negatively related to the proportion of days when the maximum temperature remained below the bobcat's lower critical temperature. My results differ from those of other studies examining factors influencing furbearer harvest that have suggested furbearer harvest is driven primarily by pelt price, and suggest that managers can influence the annual harvest of bobcats by changing season length. In chapter 2, I examine the factors affecting the spatial distribution of bobcat harvest in northeastern Minnesota. Understanding which factors limit species distributions is fundamental to predicting their response to and impact under environmental change. For species that are difficult to monitor, the spatial distribution of their harvest represents a common tool used for monitoring populations and can, with caution, be used to infer ecological relationships. Despite a nearly three-fold increase in abundance over the last 15 years and coincident increase in harvest, the spatial distribution of bobcat harvest in Minnesota has remained relatively static. Of particular interest is the near total absence of bobcat harvest in the northeastern portion of the state because it represents one of five regions designated critical habitat for the federally-threatened Canada lynx (Lynx canadensis), and anecdotal accounts suggest bobcats may threaten the persistence of Canada lynx populations. To explore potential explanations for the lack of bobcat harvest in this region I developed candidate binomial generalized linear models comparing townships where male and female bobcats were and were not harvested to determine whether hunter access and effort, climate, competition, prey abundance, or some combination thereof, accounted for the absence of bobcat harvest in this region. As judged by Akaike's Information Criterion corrected for small samples sizes, top-ranked models for males and females suggest that the distribution of bobcat harvest in northeastern Minnesota is primarily determined by bobcat ecology rather than hunter effort and access. The probability that a male or female bobcat was harvested in a township increased with white-tailed deer (Odocoileus virginianus), density and decreased with coyote (Canis latrans) density; harvest of females was also positively related to the proportion of a township composed of regenerating forest, an index of snowshoe hare (Lepus americanus) abundance. My results correspond with those of previous studies suggesting that bobcat populations can be suppressed by coyotes, that females are more reliant on snowshoe hare than males, and that white-tailed deer form an important component of the diet of bobcats at northern latitudes. Furthermore, my results suggest that reductions in winter-related mortality of white-tailed deer as predicted by climate change and consequent increases in deer density may remove one of the barriers to further colonization of the Arrowhead by bobcats, potentially increasing Canada lynx exposure to competition and genetic introgression. In chapter 3 I use data from two GPS radio-collared sibling adult female bobcats and compare estimated home range and core area size to previously published studies of bobcat space use in Minnesota and Wisconsin and provide the first published estimate of space use overlap among sibling adult females. Social organization influences carnivore demography, space use, density and abundance. In bobcats, social organization is thought to be affected by multiple interacting factors including relatedness, sex, and prey and conspecific density. To provide baseline data on the effect of relatedness on bobcat social organization, I examined space use and overlap among two sibling, adult female bobcats in east-central Minnesota, and compared these results to previously published research. Estimated bobcat home range size was similar to that of previous studies, suggesting stability in home range size across several decades and reliability in our estimates. Home range and core area overlap was within the range of previous studies. Importantly, the use of two different methods for estimating core area suggested that the subjective use of the 50% utilization distribution would have underestimated core area size and overlap. In the 4th and final chapter, I estimate how environmental features affect the suitability of habitat for bobcat reproduction and kitten survival and estimate the extent and distribution of bobcat breeding habitat in Minnesota. Distribution models have seen widespread adoption for a diversity of conservation applications because they require minimal data yet have proven highly predictive of the environmental features tolerated by animals. However, there has been limited integration of demography and distribution modeling despite empirical evidence suggesting that the environmental conditions supportive of reproduction are a subset of those supporting survival. I developed a maximum entropy distribution model of habitat suitable for bobcat reproduction and kitten survival using locations where kittens were harvested. My distribution model had good predictive ability and results suggest that the distribution of riparian forest is the preeminent environmental feature explaining the distribution of bobcat reproduction in Minnesota. Coyote abundance, row-crop agriculture and prairie were negatively associated with habitat suitability, mirroring the results of previous studies. Percentage of the study area providing suitable habitat for bobcat reproduction ranged from 23-76%, depending on the threshold used to discriminate between suitable and unsuitable habitat. Notably, I used data that agencies charged with managing bobcat populations largely already gather to develop a highly predictive model of the suitability of habitat for bobcat reproduction. Conservationists without access to harvest data can gather similar data from incidental observations of reproduction to provide better insight into the relative importance of environmental features for conservation planning and prioritization.
Burning through boundaries: collaborative governance and wildland fire planning in the United States and New South Wales, Australia.
(2010-10) Brummel, Rachel Fassbinder
Wildland fire is a complex socio-ecological phenomenon that `burns through' environmental, organizational, and geo-political boundaries. The management of wildland fire has emerged as both a crucial hazard management concern and a critical conservation priority as those living in fire-prone ecosystems experience more severe fire events and altered fire regimes contribute to biodiversity loss. This research examines two policies - the Healthy Forests Restoration Act of 2003 in the United States and the 1997 Rural Fires Act in New South Wales (NSW), Australia - which both seek to enhance inter-organizational coordination and integrated management by mandating collaborative wildland fire planning within legislation. This `top-down' approach is a departure from previous forms of collaborative environmental management that view collaboration as an emergent and voluntary process. Thus, it is unclear whether mandated collaboration fosters the flexible governance, positive social outcomes, and innovative management associated with `bottom-up' collaboration. Taking a multiple case study approach, I explore this question in four chapters, examining, in particular: 1) social learning processes in US collaborative wildland fire planning groups, 2) development of inter-organizational communication networks in NSW bushfire planning groups, 3) processes through which participants in NSW planning groups `co-construct' the fire environment, and 4) modes of governance upon which the US and NSW policies draw and the influence of these governance modes on collaborative processes and outcomes. Most broadly, I find that wildland fire planning processes and outcomes are dependent on the design of the policy mandate for collaboration, as well as planning context. For example, US wildfire planning groups had to commit to a learning-centered process on the local level, but the design of the policy mandate for collaboration influenced the type of learning that was most likely to occur. Additionally, the legislative mandate for collaboration in NSW fostered the creation of more active inter-organizational communication networks during planning than they had been prior, with important mediating factors such as group size and history of inter-organizational conflict. I also find that the imposition of a standardized planning template led to risk being the primary organizing feature of planning in NSW, promoting the co-construction of a governable fire environment that was not necessarily amenable to achieving broader, landscape-level ecological goals. Though both the NSW and US policies were created with similar goals, each draws upon distinct modes of governance to structure collaboration. The bureaucratic NSW policy focused planning towards strategic outcomes, while the network-based US policy facilitated positive relational outcomes. This dissertation has implications for collaborative environmental planning theory and practice, begins to evaluate mandated collaboration as a public policy tool, and contributes to international discussions on sustainable wildland fire policy and planning. Policy-mandates create the structural context for multi-stakeholder collaboration, but do not facilitate meaningful collaborative planning processes on their own. Mandates must be met with strong leadership, diverse participation, facilitation, and innovation on the local level. When designing collaborative mandates, policy-makers need to consider the balance of flexibility and administrative direction within the policy structure. Though bureaucratic directives may promote accountability, standardization, and strategic planning, they may also limit innovation on the local level, place power and influence in the hands of a few organizations, and promote specific (and perhaps narrow) understandings of the environment and the `appropriate' means by which to manage it. Conversely, flexible policy mandates for collaboration may allow for contextual interpretation on the local level and facilitate positive social outcomes, but may also promote limited accountability and be met by a limited set of players with `business-as-usual' approaches to management. However, in a context as dependent on coordination as wildland fire management, mandated collaboration represents a positive public policy innovation by providing a forum for inter-organizational interaction and coordinated planning. Yet, as large fires continue to be a prominent feature of certain landscapes, addressing both hazard reduction and ecological conservation objectives will be a consistent challenge. Policies need to provide substantive guidance and procedural direction on how to achieve broader conservation goals within fire management and planning.
Caring for nature: motivations for and outcomes of conservation volunteer work.
(2009-09) Guiney, Margaret Savanick
The question of what motivates individuals to become conservation volunteers is a critical question for numerous conservation programs that help maintain and improve the environmental quality in modern society. Drawing on literature from the fields of volunteer work, social psychology, leisure, program evaluation and environmental studies, I developed a theoretical framework that explores the connection between motivation and outcomes. Based on this framework, I used a mixed-method approach -- combining surveys and interviews of Minnesota Master Naturalist volunteers -- to better understand what motivates individuals to become conservation volunteers and the outcomes of their efforts. The Minnesota Master Naturalist Program is a volunteer program that educates adults about Minnesota's natural resources and provides opportunities to take part in local conservation projects. I found that both a psychological connection to nature and sense of community both affect conservation volunteer work. A connection to nature both helped initial and sustained participant motivation for conservation volunteer work. A connection to nature is likely an essential characteristic of a conservation volunteer. For most participants this connection began in childhood and volunteering as an adult helped them to stay connected to nature. Shared environmental values may be one of the more important aspects of building a sense of community for conservation volunteers. An extensive training class was a good opportunity for participants to build a sense of community. After an intensive training class, the strong sense of community diminished likely due to a lack of frequent interaction. Creating opportunities for participants to continue to interact after the class may help maintain a sense of community. Conservation volunteer work benefits the environment, the volunteer, and society.
Citizen-science monitoring of birds in urban greenspaces.
(2011-05) Homayoun, Tania Z.
As urban development spreads across North America, native migratory bird species face threats not only to breeding habitat but also to the stopover habitat they require to rest and refuel. The Mississippi River Twin Cities Important Bird Area (IBA) covers over 14,000 ha of residential, commercial, and open space along the Mississippi River between Minneapolis and Hastings, Minnesota. Identified as valuable habitat to waterbirds, we know less about how landbirds, especially migrating songbirds, use this habitat. This dissertation explores the process of designing and evaluating a citizen-science monitoring program to evaluate this urban IBA and analysis of the collected data to better understand relationships between urbanization and IBA landbird communities during both spring migration and breeding seasons. The first main chapter discusses the design and implementation of the Mississippi River Twin Cities IBA Landbird Monitoring Program, a citizen science project that engages local birders in counting the IBA's landbirds. The program's main goals are to (1) inventory landbird species that use the area, (2) determine these birds' use of the area during migration and breeding seasons, (3) use these data to estimate landbird species abundance, and (4) evaluate long-term trends. The second main chapter describes a targeted assessment of three related point-count techniques with the goal of identifying one that maximized species recorded, species detection probabilities, and overall flexibility/ease of use in citizen science. The next main chapter analyzes the program's point count data to investigate the relationships between land cover surrounding urban park study sites in the Mississippi River Twin Cities IBA and the composition of landbird communities present in the IBA during spring migration and summer breeding seasons, and to evaluate this habitat's value to both migrating and breeding landbirds. While species richness, diversity, evenness, and native migrant landbird densities responded negatively to increased impervious cover, the response in landbird community measures was more pronounced during breeding than during migration, suggesting that even lower-quality habitat within the IBA may serve migrating birds. The final main chapter discusses a website that houses the program materials and allows citizen scientists to submit their data online into a quality-controlled database. Conservation of native bird populations will require both breadth and depth of understanding and effort reaching from the continental to the local levels. This study provides a template for the process of developing a small-scale local citizen-science monitoring program, from planning and pilot season, to analysis, reporting, and connection of the program data to a larger coordinated bird monitoring scheme.
Development of a rapid monitoring approach to inform management decisions on a large tallgrass prairie undergoing restoration.
(2011-09) Brand, Genevieve Lorraine
Prairie restoration is currently unpredictable, with many sites resulting in low diversity grasslands that do not fulfill expectations. As both government agencies and nongovernmental organizations look to utilize this practice on conservation and working lands (i.e. pastures and biofuels), there is an urgent need to pause and evaluate restoration outcomes. The site specific outcomes of ecological management ubiquitous in the restoration literature and the many interacting factors common to ecological problems emphasize the need for an increase in and improvement of vegetation monitoring to assess progress and predict outcomes in the long term. In 2008, in collaboration with faculty at the University of Minnesota, I developed a rapid monitoring approach for Glacial Ridge National Wildlife Refuge, a large grassland in northwest Minnesota undergoing restoration. My goals were to reliably capture vegetation information, link outcomes to site history and utilize results to inform land manager decision-making. The rapid approach performed well in comparison with the previous effort on site. Through analysis of monitoring data, I identified several correlations among vegetation and site history parameters that were supported by the restoration literature. Restoration and reserve management professionals responded favorably to the approach in a focus group and offered suggestions for further development. With limited adjustment and testing, the rapid approach can provide goal-oriented information to land managers that will improve the effectiveness and efficiency of reserve management.
Early quaternary sea level changes and rapid diversification in the North American minnow genus Nocomis (Ostariophysi: Cyprinidae)
(2010-03) Nagle, Brett Christian
Abstract summary not available.
Ecological and sociological aspects of human-tiger conflicts in Chitwan National Park, Nepal
(2008-07) Gurung, Bhim Bahadur.
The human-tiger conflict has become a major threat to long-term tiger survival and well being of local people living around tiger reserves. Mitigation of this conflict is considered most critical in multiple use forested areas where tiger ecological needs and human livelihood needs overlap. My thesis seeks to gain a better understanding of this conflict. I investigated ecological and sociological aspects of man-eating cases in and around Chitwan National Park Nepal, with an ultimate aim of guiding mitigation policies and management. Additionally, I investigated the impact of grazing restrictions on livestock husbandry practices, and also evaluated the people's perceptions and tolerance towards tigers in Madi Valley, within the Chitwan National Park. I obtained three decades of man-eating cases (1979-2006), each case was re-examined by visiting victim's families, or person present at the time of the incidents. Likewise, tiger's responsible for killing these people were also re-investigated by visiting Park veterinarian and zoo records. The site of each human kill and tiger removal was visited to measure habitat conditions when kills were made and where man-eating tigers occurred. A total of 36 tigers killed 88 people from 1979-2006. The trend of human loss increased from an average of 1.21 persons per year prior to 1997 to 7.22 per year since 1998. The rising trend is due to primarily increasing number of people killed in the buffer zones surrounding the Park. I classified the sex, age classes, condition of man-eating tigers, and also evaluated prey base at kill sites, and aggressiveness of tigers when people came to remove victims for cremation. Nearly half of the people killed were grass/fodder cutters. In chapter 3 the impact of grazing restriction on livestock husbandry practices is examined. Household survey data and secondary information measured the impact of changing access policies. Households needed to reduce their holdings of unproductive livestock and to switch to stall feeding. Higher stall feeding required local people to gather more fodder and increased human activities in the recovering forest may contribute to increase man-eating. In chapter 4 local people's beliefs about the importance of tiger and their tolerance levels is assessed from head of the household surveys. The value and tolerance levels are analyzed based on household demographics, resource use, and interaction with tigers. Local people highly value but only have moderate tolerance for tigers. Higher valuing and tolerance for tiger were significantly influenced by household's wealth. Furthermore, poor people were found to live closer to forest, use more forest resources, have high livestock depredation resulting in lower valuing and tolerance levels for tigers. To mitigate the conflict I recommend radio-collaring problem tigers (particularly in the buffer zone) to collect tigers behavioral and movement patterns to create 'no go' zone, continue long term tiger monitoring program by extending the cooperation of the local communities, implement a tiger conservation awareness to educate local people on tiger biology, and improve compensation program to increase local tolerance towards tiger.
Ecological overlap of sympatric sun bears and Asiatic black bears in tropical forest, Thailand.
(2009-06) Steinmetz, Robert George
Asiatic black bears (Ursus thibetanus) and sun bears (Helarctos malayanus) are ecologically similar species with broadly overlapping distributions in mainland Southeast Asia. Using bear sign distinguished to species, I investigated habitat selection and feeding ecology of these bear species in 3 habitat types in Thung Yai Naresuan Wildlife Sanctuary, Thailand. I obtained imprints of claw marks on trees climbed by captive Asiatic black bears and sun bears (n = 43, all sex/ages). Discriminant function analysis was used to develop criteria for distinguishing the 2 species based on spacing of claw marks. I then applied these criteria to differentiate species-specific tree climbing in the field. Adult black bears made wider claw mark prints than adult sun bears. Based on three width measurements, captive individuals could be separated to species with 95% accuracy. Similar accuracy was achieved on independent claw mark samples from Borneo (occupied only by sun bears) and China (where only black bears occur). However, black bear cubs <1 year old could not be distinguished from sun bear adults. Strip transects (n = 71, total area = 31.2 ha) were distributed among semi-evergreen forest and mixed deciduous forest (both <1200m), and montane evergreen forest (>1200m). Every tree within transects was examined for claw marks, and other feeding signs were recorded. Claw marks were measured, and climbed trees were identified. Ages of claw marks were determined experimentally, as recent (<3 months), old (3-10 months), or very old (>10 months). Vegetation plots were established to quantify the density of fruit-tree species that bears climbed. Claw marks on trees comprised >80% of bear signs in each habitat, indicating bears fed mostly on fruit. Insect feeding signs were most common in mixed deciduous forest, where tree density was lowest. Overall sign density (both bear sp.) was 3 times higher in evergreen forest types (34-38 signs/ha) as in deciduous forest (12 signs/ha). Habitat partitioning was minimal, occurring in 1 of 3 habitats. Both bear species had similar sign densities (1-3 fresh signs/ha) in lowland habitats, but in montane forest black bears predominated (14 signs/ha), and sun bear sign was scarce despite abundant fruit. Sun bears and black bears were primarily frugivorous throughout the year and insects were of secondary importance. Signs of insect-feeding were mostly from sun bear. Of the 10 habitat variables I examined, including interspecific activity, only fruiting tree density was related to presence of feeding signs, for both bear species. I recorded evidence of feeding on 94 fleshy-fruited plant species. Use of available fruit trees by bears was disproportionate to tree abundance, suggesting selection for a mixed diet of different fruits. Niche overlap on fruit species was high (Pianka's index >0.75), and this overlap did not decrease during periods of fruit scarcity; thus, bears did not partition fruit resources. One habitat (montane forest) was used almost exclusively by black bears, and one resource (insects) was used almost exclusively by sun bears. Such exclusivity may enable each species to maintain sufficient densities, and hence coexistence, despite strong shared preferences for most other habitats and resources.
Examining genetic diversity, outbreeding depression, and local adaptation in a native fish local adaptation in a native fish reintroduction program.
(2010-05) Huff, David Derland
Reintroductions are a common approach for preserving intraspecific biodiversity in fragmented landscapes; however, reintroduced populations are often smaller and more geographically isolated than native populations. Reintroductions may therefore exacerbate the reduction in genetic variability initially caused by population fragmentation due to the small effective population size of the reintroduced populations. Mixing genetically divergent sources is assumed to alleviate this issue by increasing genetic diversity, but the effects on genetic diversity are often not monitored and there are potential negative tradeoffs for mixing genetically distinct sources. I examined the consequences of mixed-source reintroductions on the ancestral composition, genetic variation and fitness of a small stream fish, the slimy sculpin (Cottus cognatus), from three source populations at nine reintroduction sites in southeast Minnesota. I used microsatellite markers to evaluate allelic richness and heterozygosity in the reintroduced populations relative to computer simulated expectations. I then inferred the fitness of each crosstype in the reintroduced populations by comparing their overall persistence, growth rates, and relative body conditions. Finally, I modeled the response of fitness related variables in the reintroduced populations to variation in habitat using a combination of regression and ordination methods. Ancestry analysis revealed that one of the three sources had more ancestors than the other two sources at most reintroduction sites. Sculpins in reintroduced populations exhibited higher levels of heterozygosity and allelic richness than the sources, but only slightly higher than the most genetically diverse source population. Simulations of maximum genetic variation indicated only a modest expected increase over the most diverse source. Growth rate, body size, and relative body condition suggest significantly reduced fitness in second generation hybrids. I detected evidence of local adaptation in the source populations based on greater predicted fitness for each source in its respective habitat. This local adaptation is strongly associated with a gradient in winter water temperatures. My study indicates that using more than one source for reintroductions may not substantially enhance genetic diversity. Furthermore, using multiple sources risks disruption of important adaptations and may cause outbreeding depression. Future reintroductions may be improved by evaluating the potential for local adaptation in ongoing reintroduction programs.
Experiments and models to understand gene flow from transgenic fish in different environments.
(2010-01) Pennington, Kelly Marie
Transgenic fishes are nearing commercialization for aquaculture around the world. Farmed transgenic fish would likely escape from typical production facilities and interbreed with wild relatives. We tested methodologies for predicting the risk of gene flow from transgenic fish. We conducted the first study of gene flow in confined populations of transgenic animals. In two experiments several generations long, we released growth-enhanced transgenic (T) Japanese medaka (Oryzias latipes) into populations of wild-type (W) medaka in semi-natural environments. Transgene frequencies varied in the first experiment, but transgene frequencies all decreased in the second experiment. We measured six fitness traits in both genotypes, and found that T males were more fertile than W, but W males obtained more matings than T males. Next, we compared fitness traits of W and T medaka under four environments: (A) high food availability, predation absent; (B) high food availability, predation present; (C) low food availability, predation absent; and (D) low food availability, predation present. Overall, T females were more fecund than W, and fecundity was highest in Environment B. Offspring of TW and WT crosses had higher survival to sexual maturity than offspring of two W parents. Fish in Environment A reached sexual maturity sooner than fish in all other environments. W males had a mating advantage in Environments B and C. Finally, we observed gene flow in populations of T and W medaka in Environments A-D for 210 days. The final transgene frequency in Environment A was greater than in Environments C or D. We parameterized a demographic model with fitness trait values collected under the same environments, which predicted that transgene frequency in Environment A would be the highest, but also overestimated transgene frequency compared to observed results. Predicted transgene frequencies overlapped with observations in Environments B and C but not in the more extreme Environments A and D. Our results suggest that risk assessment of gene flow from T to W fish ought to consider the impact of limiting environmental factors on fitness components. Before using models to inform ecological risk assessments, predictions should be confirmed with data collected under relevant environmental conditions.
Forest restoration in Masoala National Park, Madagascar: The contribution of the redruffed lemur (Varecia rubra) and the livelihoods of subsistence farmers at Ambatoladama.
(2010-05) Martinez, Barbara Therese
Madagascar is among the most diverse places on earth, with 100% of the primates (lemurs), 99% of the amphibians, 95% of the reptiles, and almost 90% of the plants found nowhere else in the world. It is also rich in exploitable resources. Precious hardwoods like rosewood grow in the eastern rain forest. Deposits of sapphires, quartz, nickel, graphite, and gold are available. Yet it is one of the poorest countries, ranked in the lower 1/5 by the United Nations Development Program (UNDP 2009). Much of the original forest cover has been converted to agriculture, pasture, or degraded forest as a result of past non-renewable reliance on its natural resources. The government of Madagascar, with substantial support and influence from the international community, has developed a network of areas throughout the country protecting the diverse ecosystems. This is the backdrop for the present study. My dissertation research focuses on seed dispersal by the largest diurnal lemur in Masoala National Park (MNP), the red-ruffed lemur (Varecia rubra), and the attitudes of the local farmers in an effort to assess the sustainability of a forest restoration project in the Ambatoladama forest corridor in MNP. Can the park rely on lemurs to restore natural forest habitat? Do the farmers in the region understand and respect park regulations well-enough to ensure long-term compliance and acceptance of forest protection and restoration? In the first chapter, I report on the diet and activity budget of V. rubra during two field seasons in 2006 and 2007. The behavior of seed dispersers greatly affects the seed shadow of forest species; for example, the distance traveled in a day, the habitats lemurs travel through, the types of food eaten, and the amount of time resting can influence the deposition sites of passed seeds. The second chapter describes how V. rubra contribute to forest restoration through their seed dispersal capabilities. I analyzed the seed dispersal quality and quantity, including the spatial distribution, diversity, and germination success of passed seeds within the Ambatoladama corridor. Finally, the third chapter elaborates on the attitudes towards the park held by subsistence farmers living in the Ambatoladama region at the time of the study. I was interested in how people can help or hinder the future sustainability of MNP. However, between the completion of my field work and the present, Madagascar has undergone dramatic changes in its government and thus environmental legislation. The militarybacked coup in 2009 led to logging in the northeast and legalized the shipment of unprocessed rosewood and palissandre logs. This has led to massive increases in rosewood and palissandre cutting within the boundaries of MNP. I therefore analyzed the interview data from 2007 in light of the current situation in MNP.
Framing ecological risk: mass media frames in the monarch butterfly / transgenic Bt corn case.
(2009-08) Rivers, Erika Renee Lindgren
Frames are cognitive organizational structures that break the world into understandable parts. Using frame analysis as the lens through which the public receives information about the environment provides insights about the general public understanding of conservation issues. Such analysis may also be helpful in teasing out how a potential threat to biodiversity is defined and shaped by media discourse and the stakeholders who are attempting to influence the structure of discourse. The central question of this research is how have the U.S. mass media framed the potential ecological risks from genetically engineered organisms? This research uses QSR NVivo (Version 2.0.163) software to explore this question through qualitative frame analyses of opinion-leading newspapers and stakeholders' documents surrounding the ecological risks of Bt corn pollen to monarch butterfly larvae. The newspaper coverage analyzed is from The New York Times and The Washington Post, which are both widely considered news leaders in the United States. In order to uncover major stakeholder frames, selected stakeholders' documents are examined to supplement and verify the analysis. Using these analyses, this research concludes with some insights about which frames are being reported or appropriated by media entities and how frame analysis enriches discussions and theory building about how risks are socially constructed, amplified, and disseminated through the cultural institution of the mass media.
Host range and disease dynamics of viral pathogens of common carp (Cyprinus carpio), and their potential as biological control agents
(2022-11) Tolo, Isaiah
Common carp (Cyprinus carpio), hereafter referred to as carp, is a ubiquitous and destructive invasive fish in Minnesota and much of the world. There is a need for the development of species-specific, highly effective, and cost-efficient approaches for carp management that can be used across large scales. Pathogen biocontrol agents have previously been used in combination with conventional methods to control vertebrate pests at the landscape scale. Cyprinid herpesvirus 3 (CyHV-3; aka. Koi herpesvirus, KHV) and carp edema virus (CEV) are pathogens worthy of further investigation for carp biocontrol due to their host-specific pathogenicity. Both CyHV-3 and CEV are known to cause mass mortality events of carp and it is possible that carp populations can continue to decline after initial outbreaks. Despite the potential value of viruses as biocontrol agents, there are significant data gaps in the understanding of the distribution and disease ecology of carp-specific viruses in North America, a need for increased research capacity, as well as concern related to the risks of using microbial biological control agents in general. This dissertation is composed of research working to identify a safe and effective pathogenic biocontrol agent for carp. This work contributes to the understanding of the potential value of viral biocontrol of carp by identifying the distribution of CyHV-3 and CEV in Minnesota, obtaining a regional viral strain of CyHV-3 from a carp mortality event, assessing the host range and disease dynamics of these viruses, and by describing the natural ecology of CyHV-3 in laboratory disease trials and wild populations surveys.
Improving conservation efforts in the Serengeti ecosystem, Tanzania: an examination of knowledge, benefits, costs, and attitudes.
(2010-01) Schmitt, Jennifer Ann
My dissertation addresses the overarching question of how protected area managers can meet the needs/desires of local people and maintain a unique and valuable ecosystem. The Serengeti ecosystem provides the perfect backdrop for addressing this question with very poor people living in the midst of a very rich ecosystem. Other studies have also addressed this question, using primarily theoretical approaches that point out the limitations of conservation activities (Barrett & Arcese 1998; Johannesen & Skonhoft 2004) or by using socioeconomic data from part of the ecosystem to shed light on bushmeat hunting (i.e. the illegal hunting of wildlife for food) or conservation attitudes (Newmark et al. 1993; Loibooki et al. 2002; Kideghesho et al. 2007; Knapp 2007). However, these studies all lack two things, data encompassing the entire ecosystem and the incorporation of data on knowledge of protected areas. My dissertation uses data from areas throughout the ecosystem and includes the analysis of knowledge along with socioeconomics, costs, benefits, and attitudes. In determining how to improve conservation, I critically examine a key assumption of community-based conservation, i.e. that local people are benefitting from conservation. I also focus on how monitoring and evaluating more than just local people's attitudes can provide important insight and suggestions for conservation policies. Although my data is specific to the Serengeti ecosystem, my emphasis on using socioeconomic data for monitoring, evaluating, and improving conservation projects can be applied in other places. My work in the Serengeti ecosystem provides a good template for how conservation practitioners can monitor and evaluate the human dimensions of their work and how this data can improve conservation efforts. In addressing the question of how to improve conservation, I begin my dissertation with a chapter describing the socioeconomics around Serengeti National Park. Chapter one is based on a report solicited by Frankfurt Zoological Society (FZS) that provides a descriptive overview of the socioeconomic realities facing communities around the ecosystem and speaks to Tanzania's dual commitment to conservation and poverty reduction (Schmitt 2008). I amended the initial report to include data from all 20 of the villages that I studied and added analysis about differences between those villages participating in wildlife management areas and those not participating. Understanding the livelihoods and realities of people in the ecosystem is the first step to understanding how conservation projects are, or are not, affecting local communities. In my second chapter I examine the effectiveness of both community-based and fences-and-fines conservation by evaluating the benefits provided to, and costs imposed on, local people by these conservation strategies. I use empirical data on knowledge of protected areas and the costs and benefits of both conservation and illegal natural resource use to examine how current conservation strategies have affected the decisions of local people. I begin my evaluation by assessing the knowledge of local people about Serengeti National Park and its surrounding protected areas. I then analyze the different costs and benefits local people receive from protected areas and wildlife. Without changing benefits or costs in a significant manner, both community-based and fences-and-fines conservation approaches are unlikely to change behavior of local people, and therefore, unlikely to be effective conservation strategies. My third chapter identifies successes and problems in current conservation strategies by linking socioeconomic data with data on knowledge, benefits, costs and attitudes. I tie the socioeconomic data from chapter one to the knowledge, benefits and costs of chapter two, as well as examine data on local attitudes toward protected areas. I outline the socioeconomic characteristics associated with those who are knowledgeable about protected areas, those reporting benefits, those reporting costs, and those with positive attitudes of protected areas. I then point out what this larger picture of conservation suggests in terms of project success and future policies. Furthermore, I show the benefits of using more than just attitudinal data in evaluating conservation strategies.
Land cover characteristics in the Karst regon of southeastern Minnesota.
(2009-11) Williams, Mary Alice
Anthropogenic land-use activities can affect regional biophysical processes and functioning of neighboring land areas impacting the human and natural communities found in these areas. Karst landforms add complexity to land-use management. The term "karst" describes predominately limestone and dolostone landforms weathered primarily through a chemical dissolution process. Over geologic time, karst features including sinkholes, bedrock springs and fractures, sinking streams and caves form on and under the land surface. Studies that further our understanding of land cover and land use, especially in sensitive land areas can inform and improve land management and policy development for those areas. Through three projects, this thesis examined land and land-use characteristics in a regional karst landscape. Physical spring characteristics were analyzed to determine whether a subset of spring characteristics can discriminate springs into bedrock units or aquifer units. A subset of characteristics was found that discriminated the springs into both bedrock units and aquifer units. Springs had a clumped distribution on the landscape with most springs found at low elevations. For the second project, land pattern metrics were examined for a county-delineated land area and compared with pattern metrics in the major watershed overlying that county area. Differences between patterns of variation in metrics for the watershed versus the county area including greater fragmentation in the county landscape, fewer components of variation in the watershed and greater importance of land cover diversity in the watershed. For the last project, local municipal protection of regional natural resource processes was examined by determining the extent of local policy coverage on landscape functions and ecosystem services. Current coverage and gaps were identified. Policy changes directed at incorporating landscape functions into land-use planning were presented. This research provides new information about spring characteristics, land pattern metrics, and policy coverage of natural resources and ecosystem services, contributing to the accumulation of knowledge of land use and land cover characteristics, especially for karst regions, including that found in southeast Minnesota.
Learning from landowners: exploring peer exchange in the private landowner community through organizational case studies.
(2010-12) Kueper, Amanda Mary
Over half of the forested land in the United States is privately owned. As a majority of this private land is divided into individual or family-owned properties, the decisions made by these owners can have substantial implications for U.S. forests. However, traditional professional outreach efforts have been unsuccessful in reaching the majority of „family forest‟ owners, resulting in a lack of accessible management-related information for this community. This study examined peer-to-peer learning, or peer exchange, as an alternative means of diffusing information throughout the private landowner community, a burgeoning but as yet underrepresented area of research in the natural resource literature base. Case study methodology was used to examine landowner/community organizations in order to better understand a) how and to what degree peer exchange was fostered within each organization, b) how these organizations influenced landowners and contributed to information dissemination within the landowner community, and c) how the examples provided by these organizational models may be translated to inform future peer exchange and information outreach efforts in the family forest landowner community, specifically. Qualitative data were collected from five diverse landowner organizations in the United States and Australia via 61 in-depth interviews with organizational leaders and landowning members, as well as from supplementary observation of group functions. Results from analysis revealed a variety of strong common themes across cases. The organizations utilized peer exchange and social incentives in concert with professional resources to foster credible, appealing atmospheres and comfortable learning environments. Participants gained access to networks of both practical, peer-based information as well as technical, professional-based information. Additionally, organizations increased participant awareness of landowning issues and provided assistance in refinement and accomplishment of management goals. The results of this research can inform future efforts in fostering peer exchange and information dissemination in the private landowner community, with specific considerations for practitioners seeking alternative information channels for reaching the masses of family forest owners in the United States.
Lion attacks on humans in southeastern Tanzania: risk factors and perceptions.
(2009-12) Kushnir, Hadas
Lions attacked over 1000 people in Tanzania between 1990 and 2007, killing at least two-thirds of the victims. This extreme form of human-wildlife conflict has a major impact on the lives and livelihoods of local communities and threatens lion conservation in Tanzania, home to the largest lion population in Africa. Working in the two districts with the highest number of lion attacks, Rufiji and Lindi, my research examines the problem from both ecological and human perspectives at multiple scales. Overall, I aimed to: (1) identify human, ecological, and landscape-level risk factors for lion attacks, (2) determine how people currently react to attacks and what methods they believe could help mitigate attacks, and (3) understand how people perceive attacks and how these perceptions align with reality. Chapter 1, "Using Landscape Characteristics to Predict Risk of Lion Attacks in Southeastern Tanzania," examines the problem at the attack level across both districts. Using knowledge of attack locations, land cover, and important landscape features, I was able to model attack probability and then map the modeled probability in Rufiji and Lindi districts. I also extended the model to other areas in southeastern Tanzania to determine how well the model predicts high-risk areas beyond the study districts. Such a technique has potential to predict high-risk areas for future conflict in order to pinpoint prevention efforts. Chapter 2, "Human and Ecological Risk Factors for Unprovoked Lion Attacks on Humans in Southeastern Tanzania," compares human activity patterns during attacks between the two districts and examines risk at the village level in the areas with the highest concentration of attacks in Rufiji and Lindi districts. Human activity patterns during attacks differ significantly between the two districts and in each district they match with the details of daily life the area. By comparing villages with attacks to neighboring villages without attacks, I was able to identify a number of important risk factors related to wildlife presence and daily activities. Additionally, I examined the local response to lion attacks and views on appropriate measures to prevent attacks. Knowledge about local risk factors and response to attacks, and local views on prevention measures are all critical components of formulating methods to prevent future attacks. Chapter 3, "Reality vs. Perception: How Rural Tanzanians View Risks from Man-Eating Lions," examines human-lion conflict at the level of the individual by determining how people perceive the risk of lion attacks and how well these perceptions match reality. My findings indicate that even though people tend to exaggerate their overall risk, they correctly perceive specifics related to risk. This supports the need for using multiple methodologies to assess risk perceptions because only determining overall perceptions limits findings and under-represents local knowledge. The three chapters each provide different yet important perspectives on the problem that will be useful in formulating and implementing methods to reduce lion attacks on people in southeastern Tanzania. The unique combination of methodologies and scales of investigation also provide a useful framework for studies that investigate human-wildlife conflict worldwide.
The ones that got away: resource overlap and competition between a non-native fish (Oreochromis nioticus) and Thai native species, and implications for ecological risk assessment.
(2009-03) Cooper, Anne M.
Effects of non-native fish in tropical freshwater systems are commonly presumed but poorly understood. I present an approach to assess potential adverse changes in the native fish assemblage resulting from the presence of feral Oreochromis niloticus, which has an expansive naturalized range. This research is organized around an ecological risk model, consisting of a fault-tree of events. I present my findings for exposure events (site, habitat and dietary overlap) and effects events (interference competition and change in growth rates), which may lead to adverse changes in native assemblages in streams in the Eastern River system in Thailand. My research addresses two assumptions regarding the ecological risk assessment of O. niloticus in Thailand, that native piscivores, Channa spp., limit population establishment and hence ecological risk, and an economically important native species, Trichogaster trichopterus, is declining due to competition with O. niloticus. I found that Channa spp., T. trichopterus, and O. niloticus were syntopic and had high dietary overlap. When present, O. niloticus were more highly abundant than other species; which suggests their successful establishment. Native fish assemblages at O. niloticus sites were not significantly different from those at un-invaded sites, and non-native species were the only strong indicators of sites with non-natives present. Therefore, Channa spp. did not limit establishment of O. niloticus, and T. trichopterus could be negatively affected via competition with juvenile O. niloticus. I then tested whether O. niloticus adversely affect T. trichopterus through competition in laboratory experiments to determine the mechanism and outcome of competition between individuals and species in single and mixed species treatments at varying densities. Dominant fish in each tank grew more than subordinates, and O. niloticus were the dominant species in 67.7% of all mixed species tanks. The growth rate of T. trichopterus declined significantly in the presence of selectively bred O. niloticus, but the growth rate of O. niloticus was not noticeably affected by the presence of T. trichopterus. My study documents resource overlap, resource competition, and the effects of competition on growth. As such, it provides valuable insight into the ecology and conservation of native aquatic biodiversity in tropical freshwater systems.

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