Recent Submissions

  • Factors influencing thiamin concentrations in lake trout

    Heisey, AAron (SUNY Brockport, Department of Environmental Science and Ecology, 2022-01-12)
    Firstly, I would like to thank my major advisor Dr. Jacques Rinchard, for his dedication, time and commitment to his students. He has pushed me both academically and intellectually to become a better version of myself. Next, I would like to thank the rest of my graduate committee Drs. Brian Lantry, Donald Tillitt, and Matthew Altenritter who contributed to the conceptualization and execution of this thesis. Special thanks to the dedicated professionals at the United States Geological Survey - Lake Ontario Biological Station including Dr. Brian Weidel and Scott Minikiem, Dr. Michael Connerton from the New York State Department of Environmental Conservation, all those who assisted with annual lake trout and prey fish surveys, and finally to the staff at the Allegheny National Fish Hatchery for providing lake trout on short notice. This work would not be possible without their hard work and perseverance. The undergraduate laboratory assistants in Dr. Rinchard’s lab, including Jarrod Ludwig and Lillian Denecke deserved recognition for their dependability and diligence in assisting with laboratory work. Finally, financial assistance was provided by the Brockport Distinguished Professor Award, the Department of Environmental Science and Ecology, and the Great Lakes Research Consortium. On a personal note, I would like to thank my friends Kylee Wilson, Kyle Morton and the rest of the Altenritter’s lab for providing substantial moral support, thoughtful conversations and fond memories that made my time at Brockport special. Lastly, I would like to thank my parents Kim and Chris Heisey for the sacrifices they ii made to make my educational journey a reality. Their love and support made this thesis possible and for that I have immense gratitude.
  • Effects of an exotic invasive plant and microtopography on terrestrial salamander populations

    DeToy, Jessica (SUNY Brockport Department of Environmental Science and Ecology, 2021-08)
    Plant invasions can have strong, negative effects on some amphibians and represent a substantial challenge to conserving native biodiversity. However, invasive plant species do not always impose an immediate threat to amphibian populations and in some cases may facilitate increased abundance and provide additional habitat. The objective of my study was to determine how habitats invaded with pale swallowwort (Vincetoxicum rossicum) affected Plethodon cinereus and P. glutinosus salamander populations, their forest floor microclimate, and prey availability, and to determine if these parameters differed across a microtopographic gradient. I focused on these two plethodontid species because they were the most abundant within my study area at Oatka Creek County Park in Wheatland, New York during 2019 and 2020, and their many important roles within forested ecosystems have been widely studied. Plethodon glutinosus relative abundance peaked early during late summer 2019, while P. cinereus peaked during early fall. In 2020 P. cinereus relative abundance peaked in early April and late August, while P. glutinosus peaked in late summer. Peaks in the surface activity of both species corresponded to their documented life history patterns. P. cinereus relative abundance was significantly higher in uninvaded habitat during 2019 but did not differ between habitat types in 2020. There was no difference in P. glutinosus abundance between habitat types in either year. Plethodon cinereus relative abundance was highest in uphill topography types during both years, but P. glutinosus differed only during 2019. Generalized linear models predicting relative abundance showed positive relationships with the presence of the other Plethodon species, leaf litter depth, relative humidity, soil moisture, swallowwort cover, and arthropod abundance. There was also a negative relationship with temperature. Topography was an important factor in predicting relative salamander abundance, with more of an effect on P. cinereus relative to P. glutinosus, which may result from differences in microhabitat preference and morphology. Patterns in relative salamander abundance and distribution, as well as variation in abiotic parameters may be related to indirect effects of plant cover and microtopography. Ultimately, my findings suggest that swallowwort invasion does not directly and negatively impact P. cinereus and P. glutinosus and instead, may provide favorable microclimate and habitat features during periods of extreme weather, especially as dry spells and elevated temperatures become increasingly prevalent.
  • An investigation into the presence of slender false brome (Brachypodium sylvaticum) and its relationship with plant communities in New York State

    Aubertine, Megan Evelyn (SUNY Brockport, Department of Environmental Science and Ecology, 2022-08)
    Globalization has led to an increased frequency of biological introductions. These introductions have the potential to progress into invasions that negatively impact the recipient communities. However, not all species may have large impacts on native species or community assembly patterns. By understanding where invaders are likely to establish and their impacts, we can better allocate resources for early detection and rapid response to prevent future invasion. Brachypodium sylvaticum is an invasive grass in North America that is native to Eurasia and North Africa. First introduced in the Pacific Northwest, it has since made its way to the East Coast and western New York. As a relatively new invader, little is known about its environmental preferences, potential impact on communities, and its competitive ability. My study investigated these questions. In the first portion of my study I conducted vegetation surveys and environmental measurements in eight invaded and three uninvaded communities that varied in B. sylvaticum population size, environmental conditions, and forest types. As predicted, I found that water content and canopy cover determined B. sylvaticum abundance. It preferred drier soils within wetter sites, and wetter soil within drier sites. Contrary to my expectations, I found that B. sylvaticum abundance was not dependent on canopy type. Brachypodium is associated with lower species richness, which provides evidence that the invader is negatively impacting communities. However, impacts on recipient communities are limited to changes in richness as I did not find significant difference in community structure or assembly patterns between invaded and uninvaded quadrats. In the second portion of my study, I conducted a greenhouse competition experiment in which I selected species from my co-occurrence analyses to grow in competition with B. sylvaticum. I found that B. sylvaticum is not a strong competitor against another exotic grass Combined, my studies indicate that B. sylvaticum may not be a strong competitor on the east coast and may instead be a passenger of already degraded communities.
  • Acoustic telemetry data characterizes movement behaviors of yearling and sub-adult Lake Sturgeon (Acipenser fulvescens) within the Genesee River, NY

    Morton, Kyle Thomas (SUNY Brockport, Department of Environmental Science and Ecology, 2022-05)
    In the Laurentian Great Lakes basin, Lake Sturgeon (Acipenser fulvescens) populations were decimated by the turn of the 20th century, but in some areas are beginning to rebound after decades of ongoing rehabilitation efforts. In the Genesee River of Lake Ontario, hatchery-raised Lake Sturgeon have been stocked in hopes of re-establishing a healthy and self-sustaining population. To understand the efficacy of these efforts and to build an understanding of how these stocked individuals use the Genesee River and Lake Ontario habitats, ninety-nine juvenile lake sturgeon (30 sub-adults, 69 yearlings) were tagged with acoustic transmitters and tracked for approximately two years. Water quality parameters were monitored with the combined use of a USGS stream gauge and passive dissolved oxygen monitors. A multi-state model created to estimate survival and transitions from the Genesee River to Lake Ontario revealed that sub-adults had higher survival rate compared to yearlings. Yearling survival estimates were higher than previously estimated with capture-mark-recapture techniques, likely a result of being able to account for emigration. Sub-adults used both lake and river habitats more than yearlings, although both life stages frequently utilized both habitats. Seven sub-adults made large scale migrations (>100km) to either the Lower Niagara River or the St. Lawrence River. Hypoxic conditions that relate to discharge formed during the summer months within the Genesee River and appeared to limit Lake Sturgeon movements. The use of and survival in the Genesee River indicates that stocked juvenile Lake Sturgeon are using it as a nursery habitat. This has important implications when considering the efficacy of this management approach with implications for supplementing population abundance, understanding habitat use, and directing management efforts. Patterns of large-scale movements and nearshore habitat use exhibited by sub-adults should continue to be monitored as they could prove to influence vital rates (i.e., survival, recruitment, growth) and inform the degree of connectivity among populations throughout the Lake Ontario basin.
  • The effects of invasive slender false-brome (Brachypodium sylvaticum) on forest ecosystem function in western New York

    Leonardi, Andrew Frederick (SUNY Brockport, Department of Environmental Science and Ecology, 2022-05)
    The interconnectedness of the modern world has led to the spread of species outside of their normal range. Some species become invasive and can impact ecosystems by changing soil, water, and nutrient dynamics. Disrupting these important ecosystem processes can facilitate further invasion. Slender false-brome (Brachypodium sylvaticum) is an exotic bunchgrass that is invasive in North America. Its encroachment into forest understories may have implications for ecosystem processes and characteristics. The goal of this study was to understand the impacts of slender false-brome on forest ecosystem function. This study took place within two forests in western New York, one at Taughannock Falls State Park (TFSP), Trumansburg, and one in Danby State Forest (DSF), Danby. Replicate paired plots with and without B. sylvaticum were selected in each forest; each pair was matched by canopy cover and canopy type. In plots I measured vegetation, soil physical and chemical characteristics, soil moisture, soil respiration, and decomposition of leaf litter. I used generalized linear mixed models to determine variables that were the strongest predictors of soil nutrients, soil respiration, and leaf litter decomposition. All soil characteristics measured were significantly different between invaded and uninvaded plots except bulk density. At TFSP, invaded plots were enriched with organic matter (OM) and total nitrogen (TN). At DSF, invaded plots were enriched with phosphorus (P). Invaded plots at both sites had greater cation (Mg, Ca, K) concentrations, pH, and bulk density, and soil respiration and decomposition rates also increased in response to B. sylvaticum invasion. My results demonstrate that Brachypodium sylvaticum invasion significantly alters ecosystem processes, although initial site conditions do affect the magnitude and trend of some changes. Overall, B. sylvaticum has impacts on ecosystem processes like other flagship invasive species, however the impacts seem to change based on initial site conditions. I found that sites like Danby State Forest and Taughannock Falls State Park are at risk of changes in soil nutrients, soil respiration, and decomposition. A greater diversity of sites needs to be investigated to determine if other types of ecosystems are at risk from Brachypodium sylvaticum.
  • Effective control methods and the genetic and phenetic differences of European dewberry (Rubus caesius) among locations in the Finger Lakes Region of New York

    Amatangelo, Kathryn; Davis, Alexis Brianna (SUNY Brockport, Department of Environmental Science and Ecology, 2022-12)
    The colonization of invasive species is rapidly increasing due to human travel, trade, and disturbance. An area of focus in invasive species control efforts is in riparian zones, which are often highly invaded and disturbed systems. Rubus caesius (European dewberry) is a nonnative invasive woody shrub that has recently been observed to grow densely and spread through riparian ecosystems in western New York. Multiple locations have been noted, but it is not clear if all locations of Rubus caseius are correctly identified, as morphological and reproductive characteristics vary among them. Rubus caeisus is a relatively understudied invasive plant and it is not known how R. caesius is dispersing or how to effectively control extant locations. To understand the dispersal mechanisms of R. caesius I conducted a greenhouse cutting experiment and quantified the fruiting characteristics among six locations across western New York. I found that R. caesius is capable of reproducing via fragmentation regardless of source location, while only some locations produce large numbers of seeds. I investigated location differences through vegetative morphometrics and microsatellite fragment analysis. I found that all locations are identified correctly as R. caesius but there is some evidence for differentiation among the locations. Contrary to my expectations the most similar locations are not always the closest geographically. To evaluate effective control measures, I conducted a control experiment in a randomized block design at one located at Ganondagan State Historic Site in Victor, NY. I compared mechanical and herbicide treatments in different combinations of frequency, control method, and herbicide type. Treatments using chemicals were most effective in reducing the cover of R. caesius across a variety of environmental conditions. I also provide tentative evidence that repeated mechanical treatments are effective in reducing the cover of R. caesius. My determination of potential dispersal mechanisms and effective control methods will be useful for land managers as management strategies may need to differ based on reproductive traits among locations.
  • Post-implementation re-assessment of agricultural best management practices on watersheds of Conesus Lake: Effects on stream water chemistry and aquatic macroinvertebrate communities

    Beers, Daniel Thomas (SUNY Brockport, Department of Environmental Science and Ecology, 2022-11)
    Nutrient pollution is the third largest source of impairment of water quality in rivers and second largest in lakes in the US according to the Environmental Protection Agency (EPA). Agricultural best management practices (BMPs) are intended to improve water quality, reduce sediment and nutrient runoff, and remediate the effects of altered hydrology. BMPs were installed in the early 2000s in the Conesus Lake watershed and have shown initial success in reducing nutrient runoff in agricultural watersheds; however, continued monitoring of watersheds was recommended to determine if the BMPs remained effective over time. We compared water quality of agricultural BMP streams to non-BMP and reference streams in the Conesus Lake watershed to determine if BMP streams have better water quality than non-BMP streams. We also determined if there are differences in water quality in the BMP tributaries compared to prior pre- and post-BMP implementation monitoring periods. In addition, we performed an aquatic invertebrate diversity and biotic index study to determine if BMP streams have healthier populations of aquatic macroinvertebrates than non-BMP streams. We observed higher nutrient concentrations and loss of nutrients in the agricultural streams rather than the reference streams. However, our hypothesis that BMP streams would be significantly better in terms of water quality than non-BMP streams was generally not supported. In our analyses of parameters over time for the BMP streams, we observed that concentrations and loss per hectare were some of the highest we have recorded for many analytes in most streams. We also observed that BMP streams in the Conesus watershed do not have healthier invertebrate communities than the agricultural non-BMP steams. In some cases, this is likely driven by BMPs no longer implemented (or changes in land use). This could also be driven by climate change, more frequent storm events, greater storm intensity, and due to the timing of these storms. Previous studies have shown mixed results on whether BMP practices remain effective over time. BMPs should be made available throughout watersheds due to how effective they can be in reducing nutrient pollution, but they should not be considered “the be all end all” as they only provide partial solutions to watershed issues.
  • Benthic Macroinvertebrate Community Changes Following Zebra Mussel Colonization of Southwestern Lake Ontario

    Stewart, Timothy W.; The College at Brockport (1993-08-01)
    Changes in abundance and diversity of benthic macroinvertebrates inhabiting a natural cobble and artificial reef substrate in southwestern Lake Ontario were quantified following invasion of the zebra mussel, Dreissena polymorpha. Post-zebra mussel invasion data (1991-92) were statistically compared with pre-invasion data (1983) from the same sites. By 1991-92 zebra mussels comprised 73% and 90% of cobble and artificial reef macroinvertebrates, respectively, replacing the amphipod Gammarus fasciatus as the numerically dominant taxon at both sites. Overall abundance of non-zebra mussel taxa was significantly greater (p < 0.05) at cobble and artificial reef sites in 1991-92, than in 1983 before zebra mussels were present. Taxa exhibiting significant population increases at the cobble site during the time period separating the two studies were the annelids Manayunkia speciosa, Spirosperma ferox and unidentified tubificids; the gastropods Helisoma anceps,Physa heterostropha, Stagnicola catascopium, Valvata tricarinata, Goniobasis livescens and Amnicola limosa; and the arthropods Gammarus fasciatus and Orconectes propinquis. Significant population increases of Physa heterostropha, Goniobasis livescens, Amnicola limosa, Gammarus fasciatus and the trichopteran Polycentropus were observed at the artificial reef site. Although a few taxa sampled infrequently in 1983 were not collected in 1991-92, no taxa have decreased significantly since 1983. Comparisons of community composition in 1983 and 1991-92 suggest the cobble community has changed more than the artificial reef community. These changes are likely positive, as species richness was greater at cobble and artificial reef sites in 1991-92 relative to 1983, and Simpson's Diversity showed no decline. Though other factors may have contributed to observed native macroinvertebrate community changes, my results support theories that zebra mussels are facilitating energy transfer to the benthos by filter-feeding, and that mussel shoals are providing additional habitat for native invertebrate taxa.
  • The Effect of Highly Unsaturated Fatty Acids (HUFA) on Lake Trout (Salve linus namaycush) Alevins Using Artemia nauplii Enriched with Commercial Emulsions and Dry Diets

    Snyder, Blake J.; The College at Brockport (2011-10-12)
    Highly unsaturated fatty acids (HUFA) are important nutrients for fish survival, development, and reproduction. Fish oil (PO), rich in HUFA, is the dominant lipid source for first feeds in salmonid aquaculture. To determine if other lipid sources would influence survival, growth, and fatty acid profiles in lake trout (Salvelinus narnaycush) alevins, two 8-week feeding experiments were performed. Diets used in the Artemia Experiment included: diet 1, non-enriched Artemia; diet 2,SELCO-enriched Artemia; diet 3, Super SELCO-enriched Artemia; and diet 4, Bio Vita #0, all of which had significantly different fatty acid compositions. The Fish Oil Replacement Experiment used diets that differed solely in lipid source and fatty acid composition: diet 1, oleic acid (OA); diet 2, linseed oil (LO); diet 3, cod liver oil (CLO); and diet 4, lecithin (LE). Results from both experiments show that dietary lipid source and fatty acid composition can significantly influence survival, growth, and fatty acid composition of lake trout alevins. In the Artemia Experilnent, lake trout fed a non-enriched Artemia diet lacking in HUFA displayed lower growth than fish fed enriched Artemia diets that included HUFA although survival was not significantly different among treatments. Lake trout fed Super SELCO-enriched Artemia, which had the highest concentration of HUFA, did not differ statistically to lake trout fed SELCO-enriched Artemia for any growth parameter. In the Fish Oil Replacement Experiment, lake trout fed the OA diet, which was lacking in essential fatty acids (linolenic acid (18:3n-3) and linoleic acid (18:2n-6)) and HUFA, had significantly lower survival and growth. Fish fed CLO had significantly higher final length and mass but were statistically similar to fish fed the LE diet in regards to mass gain, SGR, FCR, and K. In both experiments, neutral and phospho-lipid fatty acid profiles of whole body lake trout were reflective of dietary fatty acids. These experiments suggest lipid source and dietary fatty acids can greatly affect the survival, growth, and fatty acid composition of lake trout alevins but alternatives to fish oil, such as vegetable oils, may be a suitable substitute in the first feed of lake trout.
  • Influence of Two Common Bryophytes on Acidity and Divalent Cation Concentrations in Standing Spring Water

    Bland, Stephen N.; The College at Brockport (2002-04-15)
    This laboratory experiment examines the influence of two common mosses on the pH and solute dynamics of water from a spring brook. Bivariate analysis of variance tests (MANOVA) revealed significant changes in concentrations of H+ and the combined variable, divalent cations (Ca++ & Mg++) over a three week incubation period in microcosms containing Thuidium delicatulum and Brachythecium rivulare, mosses commonly found in low order woodland streams. Divalent cation concentrations in the presence of moss were 36% higher, on average, than in similar microcosms with moss absent. In microcosms containing decomposing wood, W concentrations were 15% lower in the presence of moss. There were approximately 7 mg of divalent cations in every gram of moss tissue (AFDM), while a gram of wood contained 1-2 mg of divalent cations, values similar to those reported elsewhere in the literature. I suggest reversed cation exchange is the mechanism responsible for elevated divalent cation concentrations and changes in solute dynamics. A hypothesis concerning expected responses of fungal enzymes to the observed changes in solute dynamics is discussed.
  • Sedge/Grass Meadow Restoration on Former Agricultural Land: Analysis of Establishment Success

    Healy, Alexander Joseph; The College at Brockport (2013-05-01)
    Sedge/grass meadow wetland restoration was conducted at three study sites located in about 4 ha of agricultural land recently acquired by New York State Department of Environmental Conservation (NYSDEC) adjacent to West Creek at its confluence with Braddock Bay in Hilton, Monroe County, New York. The restoration was conducted within a 75.35 to 75.60 m (IGLD1985) elevation range previously identified as capable of supporting sedge/grass meadow in Lake Ontario wetlands. This project consisted of an initial baseline survey during spring 2009, a seed-bank emergence study that began in September 2009 and terminated in early July 2010, restoration implementation during summer 2010, and follow-up after implementation during August 2010, 2011, and 2012. Data from other Lake Ontario drowned river- mouth wetlands and a study site at Kents Creek served as references. Implementation at the three study sites began with disking in May 2010 to expose fresh soil and remove much of the old plant growth. Locally-sourced wetland seed mixes, plus seeds from Canada bluejoint grass (Calamagrostis canadensis) and tussock sedge (Carex stricta), were purchased, cold-stratified, and sown with shoulder-broadcast seed spreaders in June 2010 in the study site planted areas. Plugs of Canada bluejoint grass and tussock sedge were also hand-planted in the same areas. Sections of each disked site area were left unplanted and unseeded to serve as controls. At two of the sites, natural wetland remnants, near areas dominated primarily by river bulrush (Schoenoplectus fluviatilis) in 2009, were not disked, planted, or seeded. Plant surveys were conducted in the study site planted, control, and natural wetland areas, as well as in the 2009 baseline survey, by sampling in randomly- placed 1m2 quadrats. Plant data (frequency and percent cover of species in 1m2 quadrats) were used to calculate Importance Values; species were classified according to the National List of Vascular Plant Species that Occur in Wetlands; statistical tests were performed to determine important species and total percent cover and species count differences among study site areas; and data from all three sites across all four years were analyzed by ordination using non-metric multidimensional scaling (NMDS) in sample x Importance Value matrices. Fifteen of the 42 seeded/planted species, 38 remnant sedge/grass meadow associates, and 36 potentially problematic (agricultural weed) species were identified in study site community samples across years, and additional species continue to be found. Following restoration, seeded species diversity increased in each subsequent year, and potentially problematic species generally decreased each subsequent year. Drought conditions during 2012 likely affected survival of some wetland species with greater water demand. Control treatments on high-canopy, annual agricultural weeds by mowing at a height of about 30 cm also affected plant community changes. The seed-bank emergence study did not successfully predict ultimate community composition following implementation, likely because survival of plants from seed is often dictated by post-recruitment processes. Instead, seeded species, remnant vegetation, and nearby refuge populations seemed to contribute more to establishment in the planted areas than the original seed bank. The NMDS ordination showed that the 2009 baseline plant communities had been displaced by 2010, likely as a result of implementation actions. The ordination also showed that overall communities in the planted areas at the three sites changed from year to year and largely converged with the unplanted controls by 2012, which suggests that remnant vegetation was highly influential and nearby refuge populations made contributions as seeded species spread throughout control and planted site areas. Post-restoration sampling at the restoration sites identified 21 species that were found in the Lake Ontario drowned river-mouth wetland reference data base and six species sampled at the Kents Creek reference site. Reference data suggest that the restoration sites reflect sedge/grass meadow conditions but also contain many other species associated more commonly with disturbed sites. The future plant community at these restoration sites will likely be dependent on survival and expansion of sedge/grass meadow species, as influenced by soil moisture and competition from remnant agricultural weed species. Prolonged drought could potentially extirpate many of the seeded/planted species, especially if those conditions occurred in successive years. Monitoring results showed that competition can be mitigated by repeated, well-timed mowing that cuts taller annual plants before seed set and opens the canopy for underlying sedges and sedge/grass meadow associates currently found beneath them.
  • Soil and Vegetation Changes across a Restoration Chronosequence: An Evaluation of Wetlands Reserve Program (WRP) sites in West-central New York, USA

    Brown, Jordan; The College at Brockport (2013-04-01)
    Wetland restorations in the United States, including those sponsored by the federal Wetlands Reserve Program (WRP), are driven by the prospect of regaining critical ecosystem services lost during centuries of wetland destruction. Yet, service provision is contingent on the recovery of basic wetland functions, such as carbon (C) storage, which is especially tentative (and unverified) in WRP projects in west-central New York (WCNY), USA because those involve installing isolated wetlands on sites directly degraded by agricultural conversion. To assess recovery, I collected soil and vegetation data from 17 of WCNY’s WRP sites restored from tillage or non- tillage agriculture, aged 0-15 years since restoration at the time of sampling (August-October 2010). These were subjected to chronosequence-based analyses designed to detect divergence from a pre-restoration baseline (calculated using data from active agricultural fields paired to each WRP site) and/or convergence towards a “natural” condition (determined using data from four naturally-occurring, depressional, Palustrine Emergent wetlands within the same region). Restored WRP soils remained similar to agricultural soils in terms of organic matter, density, moisture, and belowground plant biomass across the chronosequences, indicating negligible C storage and soil development during the first 15 years. Additionally, soil development is limited in both post-tillage and post-non-tillage restorations and limited throughout the disparate habitat zone types that occur on these sites (upland meadows, emergent-dominated shorelines, and permanent open-water areas). Plant metrics like vascular species richness, cover of certain qualitative groups, and biomass matched natural wetlands within 15 years. Yet, recovery of some metrics was only detected in previously tilled sites, while other metrics only displayed recovery in untilled sites. Additionally, recovery was often detected in only one of the three habitat zones, collectively suggesting that different plant metrics are differentially influenced by the conditions imposed by historical tillage and/or the zone in which they are measured. Vegetation analyses also showed that plant community recovery can be complicated when plant parameters in restoration sites “overshoot” beyond natural conditions. In conclusion, ecological recovery in WRP restorations in WCNY is variable, depending on metric, land-use history, and habitat zone. Although generally, many plant community features recover rapidly and despite limited recovery in soil physicochemical properties.
  • Grassland bird abundance and habitat quality, and Sedge Wren (Cistothorus platensis) ecology on Fort Drum, New York

    Greer, David Thomas; The College at Brockport (2013-05-15)
    This research examines the breeding habitat preferences of grassland birds at Fort Drum, Jefferson County, New York during the 2011 and 2012 breeding seasons. In the past, Fort Drum and surrounding areas in Jefferson County have supported large numbers of obligate grassland breeding birds (OGBB). However, results from this study, when combined with data from past studies of grassland birds at Fort Drum, suggest that habitat specialists such as the sedge wren (Cistothorus platensis) and Henslow’s sparrow (Ammodramus henslowii) have been continually declining. Reasons for the decline are most likely related to a decrease in agriculture resulting in habitat loss due to succession and a shift in agricultural practices, both in Jefferson County, New York and throughout the Northeast. Habitat models suggest that most OGBBs at Fort Drum, including savannah sparrows and bobolinks, prefer increased graminoid cover and shorter, less dense vegetation. Differences in the models between years suggest that the predictive power of modeling is limited and that models should be used only as management guidelines, with a concentrated effort made to manage for large, contiguous mosaic grassland habitat.
  • The Breeding Ecology of, and Effects of Military Activity on, the Henslow's Sparrow at Fort Drum

    Krebs, Robin E.; The College at Brockport (2002-11-11)
    The Henslow's Sparrow (Ammodramus henslowii) lives in one of the fastest declining habitats in North America, the tall grass prairie. Concurrently, the Henslow's Sparrow population nationwide declined over 91% between 1966-1993. Conservation of Henslow's Sparrows requires in-depth research into the species' breeding ecology, habitat selection, and how humans impact the species. Between 1998 and 2000, I studied Henslow's Sparrow breeding ecology at Fort Drum, New York, an active army base supporting 10,000 troops and part of the largest Henslow's Sparrow breeding population in the Northeast. I studied the abundance and distribution of the Henslow's Sparrow, along with the Grasshopper Sparrow and Savannah Sparrow, using 48, 100-m radius point count plots. All three species' populations fluctuated annually between 1995-2000, based on data collected during my study coupled with data from the Environmental Division of Fort Drum Grassland Bird Study (1995-1998). The Savannah Sparrow population within 2,340 ha western grassland at Fort Drum was estimated at over 250 pairs while Grasshopper Sparrow numbers were minimal at less than 10 pairs. The point count data, however, underestimated Henslow's Sparrows' numbers when compared to banding data; based on banding data and field observations, I estimated the Henslow's Sparrow population in my study area to be 30-40 pairs.
  • Invasion Ecology of Acer platanoides in an Old-Growth Urban Forest

    Rogers, Justin Paul; The College at Brockport (2013-04-23)
    Acer platanoides (Norway maple) is an exotic tree species with invasive potential that has been described as a prolific seed producer, shade tolerant, and a strong competitor for limiting resources. It has invaded many forests in the northeastern United States and Canada, including the Washington Grove, a 10 ha forest in Cobbs Hill Park in Rochester, NY. To quantify the extent of the invasion at the Grove, I surveyed the forest canopy, subcanopy, seedlings, saplings, shrub cover, herbaceous cover, seed rain, and seed bank. In a primarily Quercus (oak) canopy, A. platanoides was relatively sparse at 31 individuals/ha, but was the most abundant tree species in the forest subcanopy with 215 individuals/ha. Two other key findings include the prevalence of other invasive species in the understory (e.g. Alianthus altissima [tree of heaven]), and a lack Quercus regeneration. I suspected that superior competitive ability of A. platanoides was key to its invasiveness and wanted to test this at the seedling stage. Two native species (Acer saccharum [sugar maple], and Quercus rubra [red oak]) and the invasive were used in nine different competition arrangements grown under low shade, medium shade, and high shade (85%, 91%, and 97% shading, respectively). I measured photosynthesis rate, stem height, and stem diameter in control, intraspecific, and interspecific competition arrangements. Height growth and photosynthetic rate both decreased significantly with increased shade. Q. rubra had the highest overall photosynthesis rate (mean = 1.98 ± 0.10 ?mol CO2 m-2 s-1) and A. saccharum had the greatest change in height (mean change = 23.7 ± 2.67%). In contrast to my expectations, I did not find any conclusive evidence 2 suggesting that the invasive A. platanoides was the superior competitor at the seedling stage. In conclusion, the Washington Grove is heavily populated by the invasive A. platanoides and if left unmanaged, the area will further progress to resemble a nonnative stand. However, this pattern does not appear to be due to competition at the seedling level. To limit the further spread of the established trees I recommend felling all of the established invasive trees and removing any emerging seedlings. A long term management plan of invasive removal and creating conditions to promote Quercus recruitment will help promote a native forest.
  • Colonization and Persistence of the Freshwater Amphipod, Crangonyx pseudogracilis, in Temporary Ponds: Aspects of its Ecology, Resistance to Desiccation, and Dispersal Abilities

    DiSalvo, Benjamin C.; The College at Brockport (2006-06-01)
    Crangonyctid amphipods occupy temporary habitats throughout northeastern North America but they are mostly known as permanent water species. Crangonyx pseudogracilis is found at high densities in temporary ponds in western New York but the means by which it colonizes and persists in temporary ponds were not well understood before my study. My objectives were to 1) learn more about and quantify the colonization abilities of C. pseudogracilis by performing experiments where holes were dug around temporary ponds; 2) explore the ability of the amphipods and other invertebrates to descend through inundated porous substrates in the laboratory; 3) compare the lifecycles of permanent and temporary populations and how the timing of mating and releasing of broods may be related to survival through the dry season; and 4) understand how and where the amphipods find refuge when a pond dries. During periods of inundation, C. pseudo gracilis was found in the top 15 cm of soil below and at the edges of the pond basin. After the pond basin became dry, they probably descended in the soil to depths greater than 45 cm. C. pseudogracilis and planarian flatworms readily colonized holes dug on the perimeter of the pond. In the lab, amphipods, flatworms, and ostracods readily descended through porous substrates. C. pseudogracilis has an annual lifecycle; the previous year's generation began dying in May and was gone by the end June. Ovigerous females were found from 23 March until 28 May. In the laboratory, amphipods survived in soil with an average moisture content of 51 % for 15 weeks. My results suggest further studies. 1) Populations of C. pseudo gracilis in permanent waters migrate to deep water during the same time of year as the temporary ponds I studied dried up. Whether amphipods in permanent waters burrow into bottom sediments during the dry season should be studied. 2) Determine how deep amphipods descend into pond sediments of temporary waters during the dry season. 3) Examine in detail the importance of the soil/water ecotone for organisms living in temporary waters.
  • Population Characteristics, Habitats, and Movements of Lake Sturgeon (Acipenser fulvescens) in the Lower Niagara River

    Hughes, Thomas C.; The College at Brockport (2002-05-01)
    Before my study, anecdotal information, such as incidental catches and reported sightings, provided the only means of assessing lake sturgeon, a species listed as threatened in New York State, in the lower Niagara River. The objectives of my study were to ( 1) assess the population of lake sturgeon by collecting and analyzing age, growth, and CPUE data, (2) compare the habitats and movements of adults and juveniles, and (3) identify potential spawning, feeding, and nursery habitats and compare use of these habitats between adults and juveniles. From late July 1998 through August 2000, 67 lake sturgeon were captured using gill nets, baited setlines, and SCUBA divers. Overall, divers (2.5 fish/night) performed better than gill nets (0.25 fish/night) and setlines (0.23 fish/night). Age of lake sturgeon captured ranged from 1 to 23 years, with most fish (n = 47) less than 10 years old. Six percent (4 out of 63) of the lake sturgeon captured had deformities, such as spinal curvature. Ultrasonic transmitters were attached to 24 fish (12 adults and 12 juveniles) to determine their habitat use and movements. Depth, current velocity, and substrate uses were similar between juvenile and adult fish. Monitoring the movements of adult fish during likely spawning temperatures (11 to 18°C) revealed that fish congregated both 8 to 10 km up river and within 5 km of the river's confluence with Lake Ontario. Based on the results of my study, I recommend that the lake sturgeon in the lower Niagara River remain listed as "threatened" by the NYSDEC and that the commercial and recreational fisheries remain closed. In addition, I recommend further studies investigating year class abundance, the cause of growth deformities, and the abundance and availability of food resources.
  • The Potential of Pigeon Creek, San Salvador, Bahamas, as a Nursery Habitat for Juvenile Coral Reef Fish

    Conboy, Ian C.; The College at Brockport (2008-08-01)
    The government of the Bahamas is considering making parts of San Salvador a National Marine Park. This study was conducted to assess the significance of Pigeon Creek, a shallow tidal lagoon, as a nursery for coral reef fishes. The perimeter of Pigeon Creek is lined with mangrove and limestone bedrock. Depending on location in the Creek, the bottom is sand or seagrass and ranges in depth from shallow intertidal sand flats to deeper, tide-scoured channels with a maximum depth of 3 m. In June 2006 and January 2007, fish were counted and their reproductive status Juvenile or adult) was recorded by sampling a total of 112, 50-m transects along the perimeter of the lagoon. Excluding silversides (Atherinidae, 52% of the fish counted), of the remaining fish counted, six families each comprised >1% of the total abundance (parrotfishes, 35.3%; snappers, 23.9%; grunts, 21.0%; mojarras, 8.5%; damselfishes, 6.1%; wrasses, 2.4%). There were few differences in effort-adjusted counts among habitats (mangrove, bedrock, mixed), sections (North, Middle, and Southwest) and seasons (summer 2006 and winter 2007). Snappers, grunts and parrotfishes are important food fishes and significant families in terms of reef ecology around San Salvador. Red Mangrove (Rhizophora mangle) which covered 68% of the perimeter of Pigeon Creek, and where 62% of the fish were counted, was an important habitat for snappers (Lutjanidae) and grunts (Haemulidae) but bedrock was the most important habitat for parrotfishes (Scaridae). The Southwest section of Pigeon Creek was important for snappers, grunts and parrotfishes, the North section for grunts and parrotfishes, and the Middle section for snappers. Only six juvenile Nassau grouper were counted in perimeter habitats, but 32 were counted during 33 minutes of drift sampling in the channel of the Southwest section of Pigeon Creek. Among the non­ silverside fish counted, 91.2% were juveniles. Although not part of this study, many juvenile Queen conch and juvenile Caribbean spiny lobster also were observed. These results suggest that Pigeon Creek is an important nursery for the coral reefs surrounding San Salvador, and should be protected from any disturbance caused by development or increased use of the area.
  • Spring Stopover Ecology and Physiology of the White-Throated Sparrow (Zonotrichia albicollis) in Western New York

    Hoh, Christina Marie; The College at Brockport (2016-06-07)
    Stopover sites are an essential part of a North American migratory songbird’s journey between wintering and breeding grounds, but annual variation in use and habitat conditions make it difficult to determine which sites are most critical for conservation. By learning which factors influence a bird’s behavior when choosing and using a stopover site, we can target certain species or locations and more efficiently invest conservation efforts. In April-May 2013 and 2014, I studied stopover refueling rate in the White-throated Sparrow (Zonotrichia albicollis), a common northeastern spring migrant, at two locations near the south shore of Lake Ontario, a natural migratory barrier. To do this, I used morphological measurements and physiological techniques that measured the concentration of two important blood metabolites, triglycerides and ß-hydroxybutyrate. Blood triglyceride concentration is a measure of fat deposition and feeding efficiency, and ß-hydroxybutyrate concentration is associated with fat catabolism and energy loss. I found that birds captured at a location ~15 km from the shore had significantly higher blood triglyceride concentrations, as well as significantly higher body condition score, than birds captured at a stopover location within 0.5 km of the shore (1.737 mM > 1.361 mM). However, after using ANCOVA to control for the effects of body condition and time after sunrise, blood triglyceride levels did not vary significantly with location. ß-hydroxybutyrate levels were not significantly higher in lakeshore-captured birds either before or after ANCOVA. Lack of statistical significance in both cases may be due to effects of small sample sizes. My results imply that birds obtain food more efficiently at the inland location, and that birds that arrive in the area in better condition may begin their cross-lake journey directly from the inland site. Birds in poorer condition may “pile up” at the lakeshore and then must compete heavily with other migrants for available resources, slowing their fat deposition rate. These results reinforce the importance of protecting high-quality stopover habitat where birds congregate near geographic barriers, but also suggest that inland habitat patches are important stopover sites that may allow some migrants to bypass nearshore areas of intense competition.
  • Habitat Requirements of Stream Spawning Walleye: An Evaluation of Habitat Suitability Index (HSI) Information and Lake Erie/Niagara River Tributaries

    Lowie, Christopher Eric; The College at Brockport (1998-12-01)
    A Lake Erie Walleye Spawning Stream Rehabilitation Plan was initiated by the New York State Department of Environmental Conservation to stabilize and enhance walleye recruitment in Lake Erie. One component of the plan includes stream habitat assessment to determine candidate streams for rehabilitation efforts. Information from research literature has been compiled to develop a Habitat Suitability Index (HSI) model and identify optimum habitat requirements for walleye. The model hypothesizes species-habitat relationships which can vary by geographical area. The objectives of my thesis project were to: (1) determine habitat conditions in a local stream where walleye spawn (control site); (2) compare these data with the HSI; and (3) use the data to evaluate four tributaries as candidates for walleye rehabilitation efforts. Spawning walleye were observed in the control stream on four days over the two-year period of study. Velocity, depth, and water temperature conditions where walleyes spawned were at the lower end of or below the optimum ranges specified in the HSI. However, optimum HSI conditions for velocity, depth, and water temperature generally do not exist in the control stream. Substrate, dissolved oxygen, and pH variables were optimum when compared to the HSI. Cluster analysis was used to group streams according to their similarities in velocity, depth, water temperature, and substrate. Significant differences (p ?0.05) in these parameters occurred among all grouped streams. No candidate stream evaluated in this study fully met the conditions found in the control stream. The candidate stream most similar to the control stream was Eighteenmile Creek. The candidate stream most similar to the national HSI model was Ellicott Creek.

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