The Staunton River is a high gradient, second order stream approximately 6 km in length located on the eastern slope of the Blue Ridge Mountains in Shenandoah National Park, VA. In June 1995, a catastrophic flood and debris flow altered the instream habitat and <i>Salvelinus fontinalis</i> population of the Staunton River. The debris flow scoured the streambed, deposited new substrate materials, removed trees from the riparian zone, and eliminated fish from a 1.9km section of the stream. By June 1998, both young-of-year (YOY) and age 1+ <i>S. fontinalis</i> had recolonized the debris flow affected area. The event provided a rare opportunity to examine recovery of the <i>S. fontinalis</i> population and instream habitat in addition to addressing potential effects of the debris flow on movement, activity, and growth of fish in the debris flow affected and unaffected areas of the stream. Post-recolonization movement and activity were monitored using two-way fish traps (weirs), mark-recapture techniques, and radio telemetry. The weirs failed to produce any movement data. Most fish (91%) in the mark-recapture study had range sizes less than 100m, however biases common to mark-recapture study designs (low recapture rate, flawed logic, etc.) hampered interpretation of results. For example, subsequent recapture of individually marked fish indicated that as many as 54% of marked fish confirmed to have been alive at the time of a recapture session were not recaptured. Radio telemetry provided information on <i>S. fontinalis</i> movement and activity at seasonal and diel scales during summer and fall. Differences in movement and activity between the debris flow affected and unaffected areas were minimal when compared to seasonal variations. During summer, range sizes were near 0m and crepuscular activity patterns were observed. During the fall range size increased and diel activity was concentrated in the mid-afternoon with a much higher peak than during summer. Basin-wide visual estimation technique (BVET) fish population surveys performed each spring and fall from 1993 = 1999 provided pre- and post-event fish population abundance and density estimates. Post-event fish growth in the debris flow affected and unaffected areas was monitored using mark-recapture techniques. Abundance and density of both YOY and age 1+ <i>S. fontinalis</i> exceeded pre-event levels within 2-3 years. Growth of YOY and age 1+ fish was significantly greater in the debris flow affected area until spring 1999. Population density appeared to have a strong negative influence on growth. The observed changes in fish growth and differences in fish size associated with population density would be of minimal importance to the typical angler but may suggest a mechanism by which <i>S. fontinalis</i> populations can quickly recover from catastrophic events. BVET habitat surveys provided information on total stream area, number of pools and riffles, pool and riffle surface area and depth, substrate composition, and large woody debris (LWD) before (1993), immediately following (1995), and four years post-event (1999). Immediately following the debris flow, the stream channel was highly disordered which resulted in an increase in the total number of habitat units and a decrease in average habitat unit surface area, total stream area, and average depth when compared with pre-event conditions. In addition, substrate composition had shifted from small to large diameter particles and LWD loading had increased in both debris flow affected and unaffected areas. Four years after the event, the total number of habitat units, average habitat unit surface area, total stream area, and average depth had all returned to near pre-debris flow levels and substrate composition had begun to shift towards smaller particle sizes. Changes in LWD loading from 1995-1999 reflected changes in the riparian zone following the debris flow. In the unaffected area, where riparian trees remained intact, LWD loading increased, whereas in the debris flow affected area, where riparian trees were eliminated, LWD loading decreased. For the most part the effects of the debris flow, although immediately dramatic, were in the long term minimal. The debris flow affected area was recolonized rapidly and abundance and density quickly rebounded past pre-event levels. Differences in fish growth between the affected and unaffected area were short lived. Any effect the debris flow affected area may have had on movement or activity was minimal when compared with seasonal variations. Most habitat characteristics reverted to near pre-event levels just four years after the flood and debris flow. Although a number of factors will influence recovery time from such events, these results indicate that immediate management action, such as stocking or habitat modifications, are not necessary in all cases. / Master of Science

The Amazon rainforest harbors the planet's highest biodiversity among terrestrial ecosystems; however, the biology and ecology of most of its species are unknown. Niche partitioning is considered a key factor allowing species co-existence, especially for morphological similar species such as spiny rats of the genus Proechimys. I examined the extent to which habitat differentiation, species body mass, and diet could explain the community composition of small mammals at a site in the southeastern Amazon. Moreover, I radio-tagged sympatric species of Proechimys spp. and Mesomys stimulax (an arboreal spiny rat) to obtain detailed autoecology information, including habitat use and use of space. I found support for niche partitioning among species and associated small mammal species with distinct successional phases of gap dynamics. I also observed among Proechimys spp. a typical polygynous organization: females appeared to be territorial against females of any species of their genus; but male territories overlapped with those of several females. Mesomys stimulax showed evidence of monogamy and possible sociality, although sample sizes were small. To identify the importance of small mammals as seed disperser of Brazil nut seeds, I conduct experiments using a combination of fluorescent powder, seed exclosures, and track plates in forests with and without Brazil nut groves, and in forests with and without Brazil nut harvesting. Among small mammals, only Proechimys spp. removed, dispersed, and preyed upon Brazil nut seeds. Proechimys spp. sometimes scatterhoarded these seeds, and hence have the potential to play a significant role in recruiting new Brazil nut trees. I also trapped small mammals and measured forest structures on the same sites used for the seed dispersal experiment, to determine the ecological effects of Brazil nut harvest on small mammal communities; however, my results showed little evidence of changes associated with the seed exploitation. My results highlight the importance of habitat heterogeneity in structuring small mammal communities, and indicate that forest management practices that alter habitats, such as partial logging, also can be expected to alter small mammal composition and diversity. Proechimys spp. have the potential to play an important role in the ecological restoration of intensive exploited Brazil nut groves.

Understanding the events and processes responsible for patterns of within species diversity, provides insight into major evolutionary themes like adaptation, species distributions, and ultimately speciation itself. Here, I combine ecological, genetic and spatial perspectives to evaluate the roles that both historical and contemporary factors have played in shaping the population structure and genetic variation of foxsnakes (Pantherophis gloydi). First, I determine the likely impact of habitat loss on population distribution, through radio-telemetry (32 individuals) at two locations varying in habitat patch size. As predicted, individuals had similar habitat use patterns, but restricted movements to patches of suitable habitat at the more disturbed site. Also, occurrence records spread across a fragmented region were non-randomly distributed and located close to patches of usable habitat, suggesting habitat distribution limits population distribution. Next, I combined habitat suitability modeling with population genetics (589 individuals, 12 microsatellite loci) to infer how foxsnakes disperse through a mosaic of natural and altered landscape features. Boundary regions between genetic clusters were comprised of low suitability habitat (e.g. agricultural fields). Island populations were grouped into a single genetic cluster suggesting open water presents less of a barrier than non-suitable terrestrial habitat. Isolation by distance models had a stronger correlation with genetic data when including resistance values derived from habitat suitability maps, suggesting habitat degradation limits dispersal for foxsnakes. At larger temporal and spatial scales I quantified patterns of genetic diversity and population structure using mitochondrial (101 cytochrome b sequences) and microsatellite (816 individuals, 12 loci) DNA and used Approximate Bayesian computation to test competing models of demographic history. Supporting my predictions, I found models with populations which have undergone population size drops and splitting events continually had more support than models with small founding populations expanding to stable populations. Based on timing, the most likely cause was the cooling of temperatures and infilling of deciduous forest since the Hypisthermal. On a smaller scale, evidence suggested anthropogenic habitat loss has caused further decline and fragmentation. Mitochondrial DNA structure did not correspond to fragmented populations and the majority of foxsnakes had an identical haplotype, suggesting a past bottleneck or selective sweep. / Thesis (Ph.D, Biology) -- Queen's University, 2011-01-11 10:40:52.476

The Amazon rainforest harbors the planet's highest biodiversity among terrestrial ecosystems; however, the biology and ecology of most of its species are unknown. Niche partitioning is considered a key factor allowing species co-existence, especially for morphological similar species such as spiny rats of the genus Proechimys. I examined the extent to which habitat differentiation, species body mass, and diet could explain the community composition of small mammals at a site in the southeastern Amazon. Moreover, I radio-tagged sympatric species of Proechimys spp. and Mesomys stimulax (an arboreal spiny rat) to obtain detailed autoecology information, including habitat use and use of space. I found support for niche partitioning among species and associated small mammal species with distinct successional phases of gap dynamics. I also observed among Proechimys spp. a typical polygynous organization: females appeared to be territorial against females of any species of their genus; but male territories overlapped with those of several females. Mesomys stimulax showed evidence of monogamy and possible sociality, although sample sizes were small. To identify the importance of small mammals as seed disperser of Brazil nut seeds, I conduct experiments using a combination of fluorescent powder, seed exclosures, and track plates in forests with and without Brazil nut groves, and in forests with and without Brazil nut harvesting. Among small mammals, only Proechimys spp. removed, dispersed, and preyed upon Brazil nut seeds. Proechimys spp. sometimes scatterhoarded these seeds, and hence have the potential to play a significant role in recruiting new Brazil nut trees. I also trapped small mammals and measured forest structures on the same sites used for the seed dispersal experiment, to determine the ecological effects of Brazil nut harvest on small mammal communities; however, my results showed little evidence of changes associated with the seed exploitation. My results highlight the importance of habitat heterogeneity in structuring small mammal communities, and indicate that forest management practices that alter habitats, such as partial logging, also can be expected to alter small mammal composition and diversity. Proechimys spp. have the potential to play an important role in the ecological restoration of intensive exploited Brazil nut groves.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering at the Cape Peninsula University of Technology, 2012 / This research project addresses the unique challenges of extensive farming in terms of monitoring and controlling remote equipment or events. Poorly maintained roads and escalating fuel costs increase difficulty of farming and the time spent on physically monitoring remote sites further reduces financial yields. The research showed that there are very few solutions that implement wireless or electronic technology to overcome the challenges associated with these isolated and arid areas and that a low-cost, long range wireless telemetry solution that is easy to use would be beneficial for the extensive farming industry. It was therefore the aim of this project to develop a remote monitoring and controlling solution that implements wireless technology to convey information of activities around the farm utilising electronic means. To be able to successfully develop a wireless telemetry solution that will accurately meet the needs of this specific sector of industry, market research was conducted. To guide the research, the QFD (quality function deployment) process for product development has been implemented. The research consisted out of various aspects including a survey, financial considerations and international comparisons. The research also aided in the understanding of the day-to-day activities and also the physical parameters of extensive farms. Also, currently available technologies and products were evaluated to establish whether similarities exist that will aid in the development of a new product. The development process was based on the results obtained in the market research and resulted in a wireless telemetry solution that overcame all the design challenges and proved to be technically feasible, successfully addressing the application requirements. Zigbee technology was utilized for wireless communication because it provided an off-the-shelf solution with a number of readily available development platforms from various technology providers. A communication range of up to 6 kilometres with a transmitted power of 11dBm was achieved for point-to-point communication and a mesh network topology has been implemented for even longer range and complete coverage on farms. Various types of measurements have been catered for, with custom-designed instrumentation which enabled measurements such as water levels, movement and analogue signals. Also, a basic user interface was developed to enable the user to monitor or control the equipment or events remotely from a personal computer, locally or even over the internet. The results of this research project showed that by carefully selecting available technologies and understanding the application, it is possible to develop a solution that addresses the monitoring and controlling needs associated with extensive farming. The wireless telemetry system that was developed resulted in a saving equal to 10% of the total expenses of the farms per year. The telemetry system is therefore a financially feasible solution with a payback period of less than 1 year and far below the initial estimated budget. Without the need to physically monitoring equipment and events, an increase in productivity and the expansion of the overall enterprise is a further benefit added unto the monetary savings. In addition to the financial benefits of implementing new wireless technology, this is an opportunity to contribute to a cleaner and more sustained future as a legacy for the next generation by reducing the carbon footprint of the farm.

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No description available.

<p>  </p> <p>Bats serve important ecological and economic roles in their communities. However, due to anthropogenic land use and human-introduced disease, bat populations in North America are facing unprecedented declines. To better inform conservation efforts for bat species in northeastern Indiana, I studied two aspects of bat ecology: (1) the effects of urbanization and agriculture on bat community composition in northeastern Indiana and (2) the roosting behavior of a population of state endangered/federally threatened northern long-eared bats (<em>Myotis septentrionalis</em>; hereafter northern myotis) in a restored mesic forest adjacent to a moderately sized city (Fort Wayne, IN). To study the first aspect, I deployed acoustic detectors in green spaces throughout Fort Wayne and the surrounding rural areas of Allen County. For each detector site, I compared species occupancy rates with site-specific characteristics at the plot scale (e.g., % canopy cover, midstory density) and at multiple landscape scales (e.g., % impervious cover within 1 km). Across 429 survey nights, acoustic detectors recorded calls from eight unique bat species, of which six species were abundant enough to conduct occupancy modeling. In four of the six species, measures of the amount of forest and forest edge in the landscape were included in one or more of the top models. The top models for the two other bat species, tricolored bats (<em>Perimyotis subflavus</em>) and silver-haired bats (<em>Lasionycteris noctivagans</em>), included measures of urban land cover and revealed a negative relationship between probability of occupancy and the proportion of high-density urban land in the area. The effect of habitat scale also differed between species. For example, models in the confidence set for eastern red bats (<em>Lasiurus borealis</em>) included variables associated with the plots surrounding detectors and with landscape features within 100 m of detectors. In contrast, the top models for hoary bats (<em>Lasiurus cinereus</em>) included landscape features at larger scales, within 500m and 1 km of detector sites. These findings suggest that both generalist and forest-obligate bat species in this study area selected spaces with greater levels of forested habitat. Furthermore, heavily urbanized areas were less likely to support the same levels of bat diversity as areas with forests and other green space.</p> <p>To accomplish the second aspect of my project, I captured bats in Fox Island County Park (Fort Wayne, IN) using mist-nets and affixed temperature-sensitive radio transmitters to four northern myotis individuals. I tracked these individuals back to day roosts, where I recorded roost characteristics (e.g., tree height, # of roost trees within 0.1 ha) and monitored bat skin temperatures (Tsk). I compared the characteristics of selected roosts to those of randomly assigned available trees in the same landscape to determine trends in roost selection preferences. Northern myotis in this study strongly preferred standing dead trees within a 31-ha patch of flooded forest on the northern border of Fox Island. These trees were highly exposed to solar radiation and were consistently warmer than ambient weather conditions, which suggests they may provide important thermoregulatory benefits to reproductive females and other members of the population.</p> <p>My research offers valuable information regarding resource use by bat communities in a landscape dominated by anthropogenic development. Urban areas containing large stretches of forests with trees in various stages of decay will be more likely to meet the needs of bats that would otherwise struggle in developed landscapes. The results of this study can be used to inform conservation efforts aimed at protecting populations of bats throughout Indiana and the Midwestern United States.</p>

No description available.