Brockport Environmental Science and Ecology Theses
http://hdl.handle.net/20.500.12648/2002
2024-03-29T09:04:57ZTraits and control of invasive mile-a-minute (Persicaria perfoliata) in western New York
http://hdl.handle.net/20.500.12648/13948
Traits and control of invasive mile-a-minute (Persicaria perfoliata) in western New York
Mackey, Erica Ann
Invasive and nuisance species are recognized as a major threat to natural
ecosystems and a leading threat to biodiversity. Mile-a-minute, Persicaria perfoliata,
is an invasive species in North America and is native to Asia and the Philippines. It
was introduced in the United States in the late 1800s and has become a serious
invasive species in the eastern United States. Herbicides, biological control, and
mechanical control methods have been effective for controlling mile-a-minute, but
their relative efficacy is not known. I evaluated herbicide, mechanical and combined
treatments for mile-a-minute over three years at two sites. All methods were effective
at reducing mile-a-minute percent cover. Treatment type affected mile-a-minute
percent cover in the first year of my study, when the mechanical-only treatment was
less effective than herbicide treatments at the first resample. However, there were no
significant differences among treatments in the second or third year of the project. My
results indicate that mechanical, herbicide, or combined treatments can effectively
manage mile-a-minute. However, because germination continues through October
revisits are needed after initial treatment applications regardless of methods chosen. I
also found that there was inter-year variability in the phenology of mile-a-minute and
was an important indicator that control methods need to be applied before flowering
occurs.
To further evaluate how phenology and plant phenotypes vary among mile-a-minute populations, I conducted a greenhouse experiment. I grew mile-a-minute
plants from seeds of regional and local populations under varying environmental
conditions. I observed that mile-a-minute grew faster, larger, and was phenologically
2
advanced under warmer, wetter, and sunnier conditions. However, mile-a-minute
survival and growth was still high under low resource conditions, and plants in low
resource conditions began to reproduce by the eighth week of the experiment. Seed
source was a significant predictor of growth and plant traits, indicating genetic
differences among populations and among seed collection times. Surprisingly,
differences among seed sources from the same populations collected at different times
were similar to differences among populations. Mile-a-minute is primed to continue
invading many habitats given its phenotypic plasticity and trait diversity produced by
sexual reproduction. Although typically found in sunny, high light edge
environments, mile-a-minute grows well in many environmental conditions, which
means it can continue to spread to new environments. Since mile-a-minute can
survive in low resource environments, land managers must survey deep into forests
near infestations for plants as they may potentially seed.
2023-09-13T00:00:00ZEvaluating annual recruitment of sea duck populations in the Atlantic Flyway using harvest and photo survey juvenile proportions
http://hdl.handle.net/20.500.12648/13947
Evaluating annual recruitment of sea duck populations in the Atlantic Flyway using harvest and photo survey juvenile proportions
Hewitt, Jacob E.
Chapter 1: Sea duck (tribe mergini) populations in the Atlantic Flyway have experienced significant declines in recent years, though underlying causes are poorly understood. Information on population demographic parameters may provide insight for wildlife managers seeking to maintain sustainable harvest. However, population monitoring capacity for sea ducks is limited relative to other migratory bird species due to their remote breeding distribution. The U.S. Fish and Wildlife Service organizes a Parts Collection Survey (PCS) which estimates recruitment in sea duck populations using age ratios (juveniles/adult), though estimates are biased due to differential harvest vulnerability between age-cohorts. I used a direct-count photo survey to calculate improved estimates of annual recruitment for long-tailed duck, black scoter, surf scoter, and white-winged scoter (hereafter sea ducks) populations in the Atlantic Flyway. I and other surveyors collected photos of flighted sea ducks from shore and by boat in 11 states from October 15-December 15 annually in 2019-2022. We classified photographed birds according to age and sex and calculated juvenile proportions of each species using a Bayesian binomial model. To compare photo survey estimates with PCS estimates, I used a paired t-test organized by year. I found that PCS estimates of juvenile proportions were significantly greater than photo survey estimates for three sea duck species, indicating a consistent positive bias in PCS driven by harvest vulnerability. I also derived novel estimates of juvenile harvest vulnerability using the mean difference between within-year estimates. My work demonstrated the photo survey methodology used in this study produced reliable and precise annual recruitment estimates for four poorly monitored waterfowl populations; I recommend managers continue to adopt this approach in future years with additional consideration given for spatial representation and refinement of image classification procedures for long-tailed duck estimates.
Chapter 2: Components of breeding productivity and survival rates in avian populations respond to dynamic environmental stressors across the annual cycle, which therein shape population dynamics over time. In sea ducks (tribe mergini), few studies have characterized the ecological factors that drive annual recruitment trends at the population level over time due to scarce scalable population information. Here, I leveraged historic harvest survey recruitment estimates (juvenile proportions) and indicators of environmental conditions at breeding, staging, and wintering areas from 1980-2017 to investigate factors influencing annual recruitment rates in eastern North American populations of long-tailed ducks (Clangula hyemalis), black scoters (Melanitta americana), white-winged scoters (M. delgandi) and surf scoters (M. perspicilatta). Recruitment rates in multiple species were positively associated with mean ambient temperatures at staging and breeding areas during spring. This supported my hypothesis that pre-nesting ice cover in key habitats limits breeding productivity by delaying breeding phenology and causing declines in female body condition. Surf scoter recruitment had a strong negative association with great gray owl irruptive migrations, suggesting surf scoters experience intensified predation pressure during low phases of vole population cycles and incur lower nest and brood survival rates. North Atlantic Oscillation patterns and staging area mean ambient temperatures in autumn showed associations with sea duck recruitment, suggesting harsh weather conditions post-fledging may precipitate early migratory movements that reduce juvenile survival rates or elicit greater proportions of adult sea ducks in subsequent harvests. My findings highlight important relationships between sea duck annual recruitment and ecological factors that may have considerable consequences for sea duck populations as ecosystems and climatic patterns undergo significant changes in the future.
2023-09-08T00:00:00ZAssessing floating treatment wetland effects on water quality at two scales and their potential to restore meadow marsh habitats
http://hdl.handle.net/20.500.12648/10512
Assessing floating treatment wetland effects on water quality at two scales and their potential to restore meadow marsh habitats
Killigrew, Kevin Anthony
Freshwater wetlands are important ecological habitats that are often degraded by water quality issues from runoff events. Floating treatment wetlands (FTWs) can be an effective method to reduce and retain excess phosphorus in watersheds through plant and microbial uptake. This study aims to support the literature on FTWs and fill gaps in knowledge by testing specific plant and substrate treatments on phosphorus reduction and investigating the sustainability of FTWs. I examined changes in phosphorus concentrations in mesocosms and retention ponds using wetland plant species native to northeastern North America: Carex stricta (tussock sedge), Iris versicolor (northern blue flag), Juncus effusus (common rush), and Eleocharis palustris (common spikerush), as well as with coconut coir substrate and no substrate. Plant combinations of the FTWs included tussock species (tussock sedge/northern blue flag), reed species (common rush/common spikerush), and a mixture of reed and tussock species. I measured the percent change in concentrations for total phosphorus (TP), orthophosphate, chlorophyll-a, dissolved oxygen, specific conductivity, and pH. I also looked at extending FTW lifecycles by investigating overwintering and establishment success of FTW plants for reuse in future projects. The mesocosm study was conducted as two separate experiments during the 2020 and 2021 summer field seasons. The 2020 mesocosm study investigated changes in phosphorus and water quality metrics between soaked coconut coir substrate and no-substrate FTWs, as well as between no-substrate planted FTWs and unplanted controls. I found that FTWs with coconut coir substrate had significantly greater orthophosphate reduction than FTWs with no substrate, but no significant differences in phosphorus reduction between no-substrate plant treatments and controls. The 2021 mesocosm study investigated changes in phosphorus and water quality metrics between FTW functional groups with unsoaked coconut coir substrate. I saw an increase in TP and orthophosphate concentrations, and no significant differences between the plant treatments due to phosphorus leaching from the unsoaked coconut coir substrate. For the retention pond study, I did not find any significant differences in changes in phosphorus concentrations between FTW plant treatment ponds and FTW control ponds due to the low FTW coverage ratio and sample size. During the establishment study, I found that tussock species were most effective in overwintering and establishment, while reed species had the greatest number of flowering individuals when planted in soil following the end of the experiment. The findings suggest that FTW studies and applications should use coconut coir substrate since it significantly reduced orthophosphate in mesocosms and improved overall growth of plants, though researchers should be sure to flush out any phosphorus that may leach from the coir. Floating treatment wetland applications can also use any native wetland plant species since no real differences were found in TP or orthophosphate concentrations between reed species, tussock species, or mixtures. Any FTW study conducted on larger scales should be sure to have FTW coverage ratios of at least 5% or greater to see any contribution of FTW plants to changes in phosphorus concentrations or impact on water quality metrics. Lastly, it is encouraged that any FTW study or application take into consideration the sustainability of the FTWs, and reuse plants for future applications or for wetland restoration efforts.
2023-06-21T00:00:00ZMovement and life history diversity of Yellow Perch (Perca flavescens) between Lake Ontario and two barrier beach wetlands in the Braddock Bay Wildlife Management Area
http://hdl.handle.net/20.500.12648/8667
Movement and life history diversity of Yellow Perch (Perca flavescens) between Lake Ontario and two barrier beach wetlands in the Braddock Bay Wildlife Management Area
Wilson, Kylee Barbara
Yellow Perch (Perca flavescens) utilize both nearshore and coastal wetland
habitats of the Laurentian Great Lakes during their lifetime and are known to exhibit
different movement life histories. However, uncertainty persists in quantifying
variability in the duration of habitat use and whether such variation manifests as
morphometric differences depending on the degree of nearshore use. To explore these
uncertainties, I used a multi-metric approach that included water and otolith
microchemistry, tissue stable isotopes (𝛿15N, 𝛿13C), and body morphometric analysis.
Manganese was useful for identifying movements between wetland and lake habitats
while carbon and nitrogen tissue isotopes revealed variable duration of wetland use
related to ontogeny. Morphometrically, Yellow Perch caught in Lake Ontario had
smaller features relative to wetland caught Yellow Perch. My research suggests that
otolith microchemistry is a useful tool for describing habitat transitions of Yellow
Perch between these two habitat types. Tissue stable isotopes indicate that some
Yellow Perch spend more time in coastal wetland habitats than others, which may
influence their susceptibility to recreational harvest. Body morphometrics appear to
reflect either use of more open habitats (e.g., Lake Ontario), or use of more complex
habitats (e.g., coastal wetland).
2022-05-12T00:00:00Z