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Publication Invertebrate Phenology and Prey Selection of Three Sympatric Species of Salmonids; Implications for Individual Fish Growth(2008-02) Ojala, Jeffrey VGrowth plays an important roll in the survival of individual salmonid fish. Diet inevitably plays a significant role in the determination of salmonid growth, with these diets consisting primarily of aquatic macroinvertebrates, predominately insect taxa. Aquatic insects have a complex life history with most having a short, aerial adult period and an aquatic juvenile stage(s). The periodicity of this juvenile stage (voltinicity) can take a few months to a few years, with the vast majority lasting a single year. These numerous and overlapping phenologies therefore have a significant impact on the availability of prey that salmonid fish find profitable. Variation in the availability and use of macroinvertebrate prey may be an important determinant of growth variation in stream salmonids. However, few studies possess the requisite information to make these links explicitly, particularly for more than one co-occurring species. Drift and benthic invertebrate availability and selection were measured for three sympatric species of stream salmonids (Atlantic salmon, brook trout, and brown trout) in a long-term study site at West Brook, Whately MA through out 2003. Benthic macroinvertebrates were found to have a strong seasonal cycle of size and abundance in West Brook. Consistent with the numerical domination of univoltine aquatic insects in this stream, relatively few large, individuals are present in the spring prior to the peak of adult emergence, with many small, individuals in the fall. This phenology combined with abiotic factors (discharge, temperature) has significant effect on the availability of profitable salmonid prey. Examining the role of prey selection revealed that salmonid fish were able to capitalize on this seasonal abundance. Additionally, salmonid species were shown to change foraging tactics from drift feeding to the consumption of both benthic and terrestrial derived prey. These results suggest that spring is a period of high prey abundance producing a common pattern of high consumption and growth for all three species. Among-species differences in diet are most manifest during periods of resource scarcity. These results indicate that seasonal dynamics in physical conditions and invertebrate phenology may combine to produce a critical period for individual growth in stream salmonids.Publication Salt Drive in the Beaver (Castor Canadensis): an Experimental Assessment with Field Feeding Trials(2012-09) Strules, JenniferABSTRACT SALT DRIVE IN THE BEAVER (Castor canadensis): AN EXPERIMENTAL ASSESSMENT WITH FIELD FEEDING TRIALS SEPTEMBER 2012 JENNIFER E. STRULES, B.M. BERKLEE COLLEGE OF MUSIC M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Stephen DeStefano Salt drive is a seasonal phenomenon common to several classes of wild herbivores. Coincident with shifts of nutrient quality when plants resume growth in the spring, sodium is secondarily lost as surplus potassium is excreted. The beaver (Castor canadensis) is an herbivore whose dietary niche closely follows that of other herbivores that are subject to salt drive, but no published studies to date have assessed the likelihood of its occurrence. To quantify if beavers experience seasonal salt drive, we designed a field experiment to measure the foraging responses of beavers to sodium-enhanced foods. We used sodium-treated (salted) and control food items (aspen [Populus tremuloides] and pine [Pinus spp.] sticks) during monthly feeding trials at beaver-occupied wetlands where water lily (Nymphaea spp. and Nuphar spp.) was present and where water lily was absent. If conventional ontogeny of salt drive was operant, we expected to observe greater utility of sodium-treated food items by beavers in May and June. Further, if water lilies supplied beavers with sodium to meet dietary requirements as is widely speculated, we expected foraging responses to sodium-treated food items at wetlands where water lilies were absent to be greater than at wetlands where water lily was present. Aspen was selected by beavers in significantly greater amounts than pine. There was no difference between the mean percent consumed of salted and control aspen sticks by beavers at lily and non-lily wetlands, and no differences in temporal consumption associated with salted or control pine sticks at either wetland type. Salted pine was consumed in greater amounts than unsalted pine. We propose that the gastrointestinal or renal physiology of beavers may predispose them to low solute loss, thereby preventing salt drive.Publication Science-Based Management of Shrubland Birds in Vermont’s Green Mountain National Forest(2012-09) Smetzer, Jennifer RPublication Spatial Ecology of American Horseshoe Crab (Limulus polyphemus) in Chatham, Cape Cod, Ma: Implications for Conservation and Management(2012-09) Martinez, Sarah EInformation regarding spawning site fidelity and movement patterns of the American horseshoe crab (Limulus polyphemus) is crucial for developing effective conservation and management strategies on the correct spatial scale. To investigate the spatial ecology of American horseshoe crabs, 75 adult animals were tracked off the coast of Chatham, Cape Cod, MA from June 2010 to November 2011 using acoustic telemetry. Two groups of horseshoe crabs were tagged in spawning habitats (separated by ~2.0 km) with differing commercial harvesting pressure: one group inside Stage Harbor, where harvesting is permitted and the other within a Marine Protected Area (MPA) where harvesting is prohibited. Network analysis revealed that horseshoe crabs exhibited fidelity to spawning habitat, but not necessarily to the habitat where they were initially tagged. Fifty-nine percent of horseshoe crabs tagged inside Stage Harbor were detected in the MPA and 13% of horseshoe crabs tagged in the MPA were detected inside Stage Harbor. Although horseshoe crabs were utilizing both spawning habitats, predictive modeling revealed little temporal overlap, suggesting that horseshoe crabs from the two spawning habitats represent local populations. Isolated and local populations are more susceptible to overexploitation than are larger populations with many migrants. To protect against overharvest and extinction of isolated and local populations, the correct identification of management units (MUs) must be a priority of fisheries managers. Horseshoe crab populations around Cape Cod, Massachusetts and New England behave differently, requiring the collection of more information so that conservation tools such as MUs or MPAs can be used most effectively.Publication Prairie Warbler Nest-site Selection, Nest Survival, and Demographic Response to Management in a Pitch Pine-Scrub Oak Barren(2012-01-01) Akresh, Michael EAs shrubland bird populations decline, there is a critical need to understand the effects of habitat management. I studied a population of color-banded prairie warblers (Setophaga discolor) between 2008-2011 in a shifting mosaic landscape within a Massachusetts inland, pitch pine-scrub oak barren consisting of persistent, newly created, succeeding, and disturbed habitats. I present data showing that the abundance and population structure at this site appears to be a function of colonization of newly created habitat by second-year birds, which are likely excluded from mature early-successional habitat by site-faithful older birds. Breeding season fecundity did not differ significantly between newly-created and mature habitats. Birds displaced by mowing or fire dispersed to nearby suitable habitat the following year, had relatively similar reproductive success, and did not negatively affect pairing or reproductive success in adjacent areas. My findings are novel and show that the effects of shrubland management on shrubland birds are beneficial in the short- and long-term. I also examined prairie warbler nest-site selection and nest survival in relation to plant leafing phenology and other factors. Prairie warblers selected distinct nest sites and certain attributes of these selected sites increased nest survival; thus I conclude that nest-site selection is adaptive. Plant leafing phenology influenced nest-site selection and nest survival in this system; its effects on birds should be considered as a potential mechanism by which bird communities can be affected by global climate change.Publication Diving Behavior and Identification of Sex of Breeding Atlantic Puffins (Fratercula arctica), and Nest-Site Characteristics of Alcids on Petit Manan Island, Maine(2012-01-01) Spencer, Sarah MDuring 2008 – 2009, we quantified foraging behavior of adult Atlantic puffins (Fratercula arctica) by deploying time-depth recorders (TDRs) on 18 adults and collected morphological measurements from 40 adults nesting on Petit Manan Island, Maine. Dive data were successfully retrieved from 5 birds foraging for 14 days in 2008, and 8 birds foraging for 18 days in 2009. Pooling across all birds, a total of 8,097 dives were recorded, with peaks in activity during 0400-0800 and 1600-2000, and no diving between 2100 and 0400. Mean (± SD) dives/bird/day was 276.4 (± 84.7), with dives grouped into bouts lasting 17.8 (± 31.5) minutes, consisting of 8.9 (± 3.4) dives. Dive depth was less than 15 m for 86% of the dives. Mean maximum dive depth across birds was 9.7 (± 1.7) m, with the deepest dive being 40.7 m. Females made fewer deep dives (27-41 m), had more midday dives (1000 - 1559), and their dives were spread across a greater number of bouts per day than males. Given a mean foraging trip length of 60.1 (± 38.3) minutes for 26 birds observed in 2009, we estimate that adult puffins foraged, on average, within 31 km of the colony. Morphological measures were recorded by a single observer and included body mass, wing chord, bill depth, bill length, culmen, and head-bill length, and represented 19 males and 21 females, based on blood sample analysis. Data were analyzed using classification trees, and our final tree used culmen length and bill depth to correctly classify 34 of 40 (85%) birds (kappa = 0.695, P < 0.01). Use of our model can greatly improve the ability of biologists to identify sex of puffins in the field at this colony site, but variability in morphological data we collected at addition colonies indicates that future work is needed to determine its applicability throughout the Gulf of Maine. During 2009, we measured burrow characteristics of alcids and empty burrows. Breeding success and burrow characteristics were measured for nests of 104 puffins, 58 guillemots and 4 razorbills, with burrow characteristics measured for an additional 12 guillemot and 56 empty burrows. Mean diameter of burrow openings of puffins, guillemots, razorbills and empty burrows were significantly different, and artificial puffin burrows had significantly smaller openings than natural while artificial and natural guillemot burrows had similar opening diameters. Hatch, chick, and nest success of puffins was similar among burrow types, but guillemots had higher hatch and nest success in artificial burrows. The variables we used to create models for predicting hatch and nest success for puffins and guillemots had inadequate discriminatory power to predict success.Publication Black Bear Movements and Caribou Calf Predation in Newfoundland(2012-02) Rayl, Nathaniel DThe population trajectory of woodland caribou (Rangifer tarandus caribou) in Newfoundland is currently determined by low calf survival due to high predation rates during the first 6-8 weeks after parturition. Most caribou in Newfoundland congregate and give birth in open calving grounds; consequently, in order to investigate predator-prey interactions, design research, and develop mitigation strategies, the geographic extent of the caribou calving grounds must be properly identified. We used VHF telemetry locations of caribou calves, collected from 2003-2010, to determine the spatial and temporal extent of caribou calving grounds in three study areas in Newfoundland. We put GPS collars on 47 black bears (Ursus americanus) in 3 caribou ranges where bears are having a significant impact on caribou recruitment by preying on calves during the calving season. Bear movements were greatest during the calving season, potentially increasing encounters with calves. Some bears migrated to the calving grounds just prior to caribou parturition, indicating deliberate broad-scale selection of areas of high calf density. Bears displayed interannual fidelity to calving ground usage patterns during the calving season, with some bears using the calving grounds every year, while others did not. We estimated the probability of a bear spending time in the calving grounds during the calving season as a function of the bear’s sex and mean distance to the calving grounds with logistic regression. We found that as distance increased, the odds of a bear spending time in the calving grounds decreased, and that at any given distance the odds were greater for male bears than for female bears. Our results indicate that some bears in Newfoundland are likely caribou calf predators, while others are not, and that the sex and broad-scale distribution of bears influenced the probability of a bear participating in calf predation during the calving season. The probability distribution of calf-visiting bears could be used to develop management practices to mitigate the impact of bear predation on declining caribou herds in Newfoundland.Publication An Investigation of Human-Error Rates in Wildlife Photographic Identification; Implications for the Use of Citizen Scientists(2012-02) Chesser, MeganRapid technological advancements in digital cameras and widespread public access to the internet have inspired many researchers to consider alternative methods for collecting, analyzing, and distributing scientific data. Two emerging fields of study that have capitalized on these developments are “citizen science” and photo-id in wildlife capture-mark-recapture (CMR) studies. Both approaches offer unprecedented flexibility and potential for acquiring previously inconceivable datasets, yet both remain dependent on data collection by human observers. The absence of rigorous assessment of observer error rates causes many scientists to resist citizen science altogether or to fail to incorporate citizen-collected data into ecological analyses. This same need for consistent measurement and documentation of the type and frequency of errors resulting from different observers is mirrored in numerous ecological studies employing photographic identification. The driving question of interest behind this thesis rests at the intersection of these two fields: can citizen scientists provide an effective alternative to commonly utilized computer-assisted programs used with large photo-id databases from wildlife studies? To address this question we reviewed the history of wildlife photo-id in order to gain a better understanding of knowledge gaps caused by a failure to consistently report human error rates (Chapter 1). We then piloted a crowdsourcing approach to distributed photographic analysis by soliciting responses to image comparisons from a large number of untrained observers (Chapter 2). We found that observers correctly assessed 99.6% of all comparisons, but that the predictor variables for the two types of error (false positive and false negative) differed. Building upon a deeper understanding of the history, limitations, key issues, and recommendations for researchers considering using photo-id, we recommend the expanded use of citizen science methods as an effective alternative to computer-assisted approaches with large image libraries. Error rate improvements should allow scientists to more readily accept data collected by untrained observers as valid, and will also contribute to improved accuracy of ecological estimates of population size, vital rates, and overall conservation management of threatened or endangered species. Additionally, the general public will benefit from expanded opportunities to engage with and learn about the scientific process.Publication Status, Movements, and Habitat Use of Moose in Massachusetts(2011-01-01) Wattles, David WMoose (Alces alces) have been re-established in much of the historic range in the northeastern United States. Recently the southern edge of the species ranges has been extended southward into southern New England and northern New York from established populations in northern New England. The southern expansion raised questions as to the ability of this northern species to cope with higher temperatures, areas densely populated by humans, and different forest types further south. In light of these recent developments, we conducted a literature search on moose in the northeastern United States and distributed a questionnaire and conducted phone interviews with biologists responsible for moose management across the region to determine the status and management of moose in New England and New York. Furthermore, in 2006 we initiated a study on the home ranges, movements, and habitat use of moose in Massachusetts. We captured and collared moose with Global Positioning System (GPS) collars to track their movements in the Commonwealth. The surveys and interviews with the state biologists revealed that moose populations appeared to be stabilizing in southern New England. However, the moose population continued to grow in northern New York. Moose populations in northern New England were managed with an annual fall harvest, but moose hunting was not allowed in southern New England or New York. Throughout the region moose vehicle collisions were a major concern (>1,000 occur each year) including several that resulted in human fatalities. The collaring study has revealed the importance of maintaining a variety of forest cover types, age classes, and wetland habitats to meet the seasonal needs of moose, including early successional habitats created by logging that appear to be important for moose. Mean home range sizes were 64.9 km2 (SE = 12.9) and 73.3 km2 (SE = 9.4), respectively, for females and males in central Massachusetts, and 164.5 km2 (SE = 62.6) for males in western Massachusetts. Moose often interacted with roads and human development on the uplands, but used less developed areas of their home ranges. This demonstrates the importance of preserving the integrity and connectivity of the forested landscape of Massachusetts.Publication Spatial And Temporal Dynamics Of Land Use Impacts On Water Quality In Watershed Systems(2007-01-01) Tsvetkova, OlgaABSTRACT SPATIAL AND TEMPORAL DYNAMICS OF LAND USE IMPACTS ON WATER QUALITY IN WATERSHED SYSTEMS SEPTEMBER 2007 OLGA TSVETKOVA, B.S., NOVGOROD STATE UNIVERSITY, RUSSIA M.S., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Timothy O. Randhir Predicting land use change and assessing watershed tradeoffs between the watershed system components through system simulation helps to determine future nutrient and sediment load reductions needed to obtain a particular water quality standard. This also helps to examine the tradeoffs among nutrient and sediment load reductions that achieve the same water quality objective. Tradeoff assessment is a useful tool to meet agricultural and urban needs in regard protecting water quality. The purpose of this study has been to develop and apply a spatial temporal dynamic simulation model for the land use change and a hydrologic dynamic simulation model for the estimation of the tradeoffs relationships between watershed contaminants and attributes. The Spatial – temporal dynamic model is applied to one of the subbasins within the Blackstone River Watershed to predict potential land use changes in the subbasin. Results show that the increase in urban land use in the watershed is associated with the decline in agricultural and forest land. The overall preliminary results show that urbanization could become a serious problem in the future. The results emphasize the need to protect agricultural area in rapidly changing watersheds. In the watershed tradeoffs simulation modeling, the effect of land use change on water quality is simulated using the Soil and Water Assessment Tool. The methodology is applied to the Blackstone River watershed and its 115 subbasins. Regression statistics as well as graphical techniques are used for accurate evaluation of the model. Water quality and quantity estimated using an array of equations to simulate watershed processes. It is observed that a fairly high variability exists for soluble phosphorus, mineral phosphorus, and sediment yield. The tradeoff relationships between watershed components are described by tradeoff equations and graphically. The regression results indicate that the highest correlations exist between nitrate and surface runoff and between mineral phosphorus and sediment yield. The final tradeoff matrix is developed for the study watershed and could be used to assess various policies that include policies on nutrients, water resources, and land use.Publication Developing Standardized Metrics to Quantify the Temporal Distribution of Migrating Anadromous Herring: Comparing Adult Returns Across Coastal Rivers(2011-01-01) Burak, Matthew KUnderstanding, quantifying, and comparing the temporal distribution of anadromous fish spawning migrations is an important yet vexing problem for fisheries research, management, and conservation. Central to this problem is the lack of a representative and comprehensive standardized suite of quantitative metrics to characterize the complex, multidimensional temporal distribution of migrating anadromous fish. Without this, it is not possible to develop effective sampling regimes, extrapolate counts to accurate population estimates, understand the basic ecology and behavior of anadromous fish, or make the comparisons through time and across river systems that are fundamental to sustainable conservation. In this thesis, I define, calculate, and compare 17 metrics that characterize the temporal distribution of migrating adult river herring [two closely related clupeids, the alewife (Alosa pseudoharengus) and blueback herring (Alosa aestivalis)] as they return to spawn. These metrics are based on fish counts from three southeastern Massachusetts river systems that were obtained through a low-cost video monitoring system.Publication Factors Affecting Survival and Cause-specific Mortality of Saiga Calves (Saiga tatarica mongolica) in Mongolia(2011-01-01) Bayarbaatar, BuuveibaatarFactors affecting juvenile survival are poorly known in the world’s most northern antelope, the endangered saiga (Saiga tatarica), yet they are fundamental for understanding what drives population change. For saiga neonates monitored in Sharga Nature Reserve, western Mongolia, during 2008–2010, male and single calves were heavier than those of female and twins, respectively. However, there was no significant difference in seasonal and annual survival rate between male and female or singletons and twins. Litter size and birth mass varied among years, and there was a negative relationship between these variables. Multiple regression models suggest that summer precipitation in previous years and spring mean temperature explained inter-annual variations in twinning rate, and mortality was highest during summer. Covariates providing the best model fit included year, litter size, and body weight, suggesting that environmental conditions influence twinning rates and body mass may play a key role in neonate survival rate in the first year. We identified 3 sources of mortality – predation by raptors, foxes (red and corsac, Vulpes vulpes and V. corsac), and lynx (Lynx lynx). Most predation was by raptors, such as golden eagles (Aquila chrysaetos) and cinereous vulture (Aegypius monachus). Our results point to both environmental and biotic factors affecting juvenile survival.Publication Reproductive maturation and diel reproductive periodicity in western Gulf of Maine haddock(2011-01-01) Anderson, Katie AA new macroscopic ovarian reproductive maturity index for haddock, Melanogrammus aeglefinus L, was developed to improve field collection of reproductive stage data. The index was tested, validated and revised based on a comparison with a laboratory histological staging method. The comparison of field and histological observations helped to improve the field index and methodologies and provided useful insight into the reproductive biology of Haddock. Although laboratory staging based on histology is inherently more accurate than any macroscopic field staging method, field observations can reveal weaknesses in the laboratory approach due to sampling bias. The revised field index includes three new macroscopic stages that represent a progression in final oocyte maturation from early to late, which were found to be reliable for staging spawning readiness in the field. This index was then used to study a population of Haddock in the Gulf of Maine to determine if it exhibits diel spawning periodicity. Commercial fishing vessels were chartered for 25 dedicated longlining trips to collect sexually mature haddock in the Southwestern Gulf of Maine at locations identified by commercial fishers as having spawning aggregations. In order to examine diel effects on haddock reproduction, the change in catch per unit effort and percentage of male and female haddock of all reproductive maturity stages together with the gonadosomatic index were observed across a 24 hour diel cycle. Only females in hydration stage 3 (defined as late final oocyte maturation stage ovaries with 50-75% of oocytes hydrated) were significantly affected by time of day with significant increases in both catch per unit effort and percentage of hydration stage 3 haddock during the night. Because H3 is the most advanced reproductive stage observed prior to a spawning event and therefore the best indicator of imminent spawning these results demonstrate that female haddock in Southwestern Gulf of Maine primarily spawn during night hours with a peak between 2100 and 0100 hours. No diel trend was observed for any male reproductive stages. Additionally, no diel trend was observed in male or female reproductive stages unrelated to spawning including immature, spent and resting.Publication Managing Vegetation to Restore Tern Nesting Habitat in the Gulf of Maine(2011-01-01) Lamb, Juliet SFollowing catastrophic exploitation throughout the North Atlantic, breeding seabird populations have begun to recover thanks to regulatory protection and restoration and management efforts. As bird populations increase, new challenges emerge, including overgrowth of vegetation that limits the open nesting habitat favored by most tern species. Though managers have used a variety of measures to reduce vegetation cover, these techniques have rarely been quantified or compared experimentally. During the summers of 2009 and 2010, I applied two different techniques, controlled burning and artificial weed barriers (muslin fabric and artificial turf) to experimental plots on Eastern Egg Rock and Outer Green Island, near-shore seabird nesting islands in mid-coastal Maine. I then monitored vegetation regrowth and use by nesting terns to assess the effectiveness of these techniques for opening and maintaining Common Tern nesting habitat during a full breeding season, comparing treated plots to vegetated control plots and existing tern nesting habitat. Burned areas did not remain open for the full nesting season, but regrew shortly after laying, leading to near-complete nest failure in these plots. Tern nest and fledging success was similar in weed barrier (1.37 chicks/pair) and untreated tern nesting habitat (1.38 chicks/pair) plots. Replacement of existing vegetation, tested at a limited scale on Outer Green Island, did not succeed. These three techniques represent only a small fraction of vegetation management techniques used throughout the North Atlantic region. Through literature review and consultation with North Atlantic colony managers, I collected information on vegetation management on 34 tern nesting islands between 33 and 55° N latitude and developed a summary of different vegetation control techniques used. I identified 14 technique types suitable for use in nesting colonies: i.e., that can be applied before and after (but not during) the nesting period of May-July, that do not cause destructive impacts to the surrounding ecosystem, and that involve materials and labor that can be transported to inaccessible offshore islands. Of these techniques, 8 created usable tern nesting habitat for a full breeding season, and the most successful techniques required constructing habitat over existing vegetation. The success of different methods depended heavily on the plant communities and soil types involved. In general, vegetation management options were more limited and less successful for elevated, rocky islands than for low, sandy islands. Often, techniques that successfully removed one species or group of species (i.e., perennial grasses) failed due to rapid colonization by other species (i.e., herbaceous annuals). This review of past and ongoing vegetation management techniques used on seabird nesting islands, including their costs, methods for application, and effectiveness, provides seabird managers a reference when evaluating current and future vegetation management programs.Publication Habitat Use, Productivity, and Fruit Selection of Birds in Early-Successional Habitats in Western Massachusetts(2011-01-01) Labbe, Michelle AEarly-successional habitats have become rare in much of the eastern United States, largely due to landuse change, forest maturation and the disruption of natural disturbance regimes. In addition to providing nesting habitat for shrubland species of high conservation concern, wildlife openings may be an important habitat for mature-forest birds during the postfledging period – a critical phase in the avian lifecycle with the potential for high mortality. The habitat requirements of birds during this time period are poorly understood. In this study I examined the relationship between habitat and landscape characteristics on; 1) the abundance of forest nesting birds in shrubland habitat during the postfledging season, and 2) the reproductive success of shrubland bird species. And lastly, I also examined the relationship between avian body condition and seed dispersal, with a focus on comparing native and invasive species. I found that the abundance of forest birds was strongly influenced by landscape characteristics, as well as food abundance and structurally complex vegetation. Shrubland birds varied in their response to habitat variables, but overall productivity was positively related to taller vegetation structure, and was negatively related to lower-dense vegetation. Frugivore diets were generalized, yet they selected native fruit more often than invasive fruit, and invasive fruit negatively affected condition. My findings are consistent with the results of previous studies of habitat use among postfledging birds, and suggest that, like for forest birds, habitat requirements for shrubland birds during the postfledging period differ from those during the nesting season. Hopefully these results will encourage other studies of this important, but poorly understood stage of the avian lifecycle.Publication Laboratory Evaluation of Modified Traveling Screens for Protecting Fish at Cooling Water Intakes(2007-01-01) Black, Jonathan LSection 316(b) of the Clean Water Act requires thermal power generating facilities to minimize adverse environmental impact resulting from the operation of cooling water intake structures (CWIS). Adverse environmental impact can occur when aquatic organisms are impinged on traveling water screens. Modified traveling screens were developed to improve the post-impingement survival of organisms. These screens have been used at a few power plants and are now being considered at additional facilities to reduce the mortality of juvenile and adult fish. Existing biological efficacy data show that post-impingement survival is highly variable by species. The majority of previous installations are at estuarine facilities. As such, there is a lack of biological efficacy data with many of the freshwater species commonly impinged at CWIS. In addition, most of the existing modified screen installations were installed prior to 1990. Since that time, improvements in screen designs have increased survival. For these reasons, the existing biological efficacy of the new screen designs was limited and largely unknown for many freshwater species. The mortality, injury, and scale loss rates of 10 species of freshwater fish impinged and recovered with a modified traveling screen were evaluated in the laboratory. Species tested included: golden shiner (Notemigonus crysoleucas); fathead minnow (Pimephales promelas); white sucker (Catostomus commersoni); bigmouth buffalo (Ictiobus cyprinellus); channel catfish (Ictalurus punctatus); hybrid striped bass (Morone chrysops × M. saxatilis); bluegill (Lepomis macrochirus); largemouth bass (Micropterus salmoides); yellow perch (Perca flavescens); and freshwater drum (Aplodinotus grunniens). Fish were impinged at 0.3, 0.6, or 0.9 m•s-1 velocity. Mortality, injury, and scale loss rates were generally low. Mortality rates did not exceed 5% for any species and velocity tested, indicating that this technology has potential to substantially reduce impingement mortality at CWIS. Despite a general trend toward increasing mortality at higher velocities, velocity was only a significant factor in the mortality of bluegill (P=0.0005). Injury and scale loss rates were low for most species tested, although they were more variable than observed rates of mortality. There was a trend toward lower mortality, injury, and scale loss in larger fish. In all cases where fish length was a significant factor (P<0.05), the pattern of decreasing mortality, injury, and scale loss as fish increased in length was constantly observed. Additional tests were undertaken with channel catfish, fathead minnow, and golden shiner to assess the effect of duration of impingement on mortality, injury, and scale loss. Longer durations of impingement appeared to result in higher mortality, injury, and scale loss, especially at durations of impingement greater than 6 minutes. However, longer durations of impingement could be avoided at most cooling water intake structures by continuously rotating screens.Publication Spatial Ecology of Eastern Coyotes (Canis latrans) in the Anthropogenic Landscape of Cape Cod, Massachusetts(2010-01-01) Page, MailiHistorically, coyotes were associated with the western United States. During their expansion eastward, coyotes have become more tolerant of humans and have been able to live in varying degrees of urbanization. One main question ecologists around the country are asking is how coyotes are surviving in anthropogenic environments. To aid in answering this question, I have compared coyote land use preference generally and specifically during coyote breeding season, winter and summer, human tourist seasons, and day and night. I also compared coyote land cover preference for deciduous and evergreen cover types during natural seasons. I found that, in general, there was a high variation of preference between and within land use categories. More broadly however, they prefer natural areas over non-natural areas. They used natural and non-natural land use types equally in winter and summer, and during tourist and off-tourist seasons with increased variation in preference during seasons with higher human activity. They had a higher preference for non-natural land use types at night. There is no difference in coyote preference for deciduous or evergreen cover types during the seasons.Publication Behavior and Habitat Use of Roseate Terns (Sterna dougallii) Before and After Construction of an Erosion Control Revetment(2010-02) Grinnell, CoreyAn erosion control revetment was constructed at the Falkner Island Unit of the Stewart B. McKinney National Wildlife Refuge, Connecticut during the winter of 2000–2001. At the time, Falkner Island was the fifth largest breeding colony site for the federally endangered Roseate Tern. This study measures and describes some baseline information regarding Roseate Tern nesting, behavior, and habitat use at Falkner Island during the three breeding seasons prior to revetment construction (1998–2000). This baseline information is then compared to similar information from the first breeding season following revetment construction (2001). For Roseate Tern adults, this study examined changes in pre-nesting habitat use, nest site distributions, and pre-nesting behavioral time allocation. Changes in habitat availability and habitat use by Roseate Terns are compared as a result of the revetment construction. Roseate Terns used rocky beach in a greater proportion than other habitats before revetment construction, and used revetment boulders in a greater proportion than all other habitats after revetment construction. Roseate Terns nested more often in artificial sites (nest boxes and tires) than in natural sites in all years of the study. The mean date for the first eggs in each nest did not differ between years. We observed more Roseate Terns prospecting artificial nest sites (n = 66 times) than natural sites (n = 21 times) for three years of this study. Prospecting behavior occurred later in the season in some subcolonies, but this difference did not appear to be related to the construction. For Roseate Tern chicks, this study investigated the use of crevices as hiding places from before (1999–2000) and after (2001) the construction of an erosion control revetment. In all years, Roseate Tern chicks used crevices found under artificial nest sites more frequently than expected by chance when compared to crevices found in other microhabitats. Chicks also used crevices formed in various microhabitat types at different stages of development. The erosion control revetment created crevices that had larger openings, steeper floors, and deeper lengths than those previously used by chicks before construction. In the year after revetment construction, the openings of crevices used by chicks that died were wider than crevices used by chicks that survived. We discuss our findings in the context of the potential consequences that the revetment construction had on Roseate Tern chick survival.Publication Evaluating the Effectiveness of Road Passage Structures for Freshwater Turtles in Massachusetts(2010-01-01) Paulson, David JRoads are long linear features on the landscape that impact wildlife and their habitats. Among all forms of wildlife turtles are one of the most negatively affected by roads. Wildlife biologists and civil engineers have developed and implemented road design measures to mitigate the negative effects associated with roads. One common approach used to reduce road mortality and to facilitate movement of turtles is to construct a road mitigation system. There are currently 28 road mitigation systems for wildlife in Massachusetts, of which 14 were specifically built for turtles. We identified all known systems in Massachusetts and collected site and structural design information for each. In addition, we also examined the relative effectiveness of experimental passages for freshwater turtles. Structures were evaluated with respect to how their height, width, and position (at or below-grade), influenced the movements of painted turtles. A total of 190 turtles were exposed to the experiential trials and their behavior was characterized by 3 response variables (Total time to complete the trial, Total hesitations observed, and Success based on no hesitations and completion of the trial in less than 120 minutes). We concluded that painted turtles exposed to below-grade tunnels were less hesitant and traveled faster through them as the tunnel size increased from 0.6 m x 0.6 m to 1.2 m x 1.2 m. The 1.2 m x 1.2 m tunnel size overall proved to be the size with the fewest hesitations observed, fastest total times, and highest success rate.Publication Variation in Winter Estuarine Habitat Use by Bluefish in Northeastern Florida with Implications for Growth and Condition(2009-09) Murt, John SAge and growth were determined from otoliths for 181 juvenile bluefish, Pomatomus saltatrix, collected using a variety of gear in northeast Florida during 2003 and 2005. Three distinct cohorts were identified recruiting to the near shore waters during spring, summer and fall. Growth rates were high regardless of cohort or season. To compare pre- and post-recruitment growth rates, models were fit to individual growth trajectories using change point analysis. Post-estuarine growth rates were generally higher. Growth rates and hatching times were within the range of those obtained in other bluefish studies conducted at higher latitudes. As this is the only area where winter recruitment of bluefish has been observed, coastal Florida habitats may be essential for the bluefish stock and will need to be carefully monitored in future studies. A technique to estimate the lipid content of bluefish was developed using fat stage (subjectively assigned based on mesenteric fat around the stomach), fish length, and fish weight. A highly significant relationship was observed between fat stage and lipid content in a generalized linear model. The visual lipid content technique provides rapid results, is inexpensive and could be easily implemented into current fisheries sampling methods. Total lipids were also extracted from potential bluefish prey species collected during sampling. Prey lipids ranged from 0.88% to 19.52%. Regular prey species from the MAB; Atlantic silverside and bay anchovy contained 3.49% and 3.19% mean lipids respectively. Highest lipid content was observed in mullet (Mugil spp.) (19.52%) and was significantly higher than other available prey species. A previous study indentified a decline in bluefish lipids as winter progressed as well as a prey preference for mullet. We propose mullet are the preferred prey choice due to their high lipid content.