Degraded peatlands release 100-200 g-CO2 eqv. m-2 yr-1 in net emissions and account for more than 10% of global CO2 emissions. The success of bog restoration is dependent on creating suitable moisture conditions for the donor material to establish, propagate, and develop a new layer of Sphagnum that has hydrophysical and water retention properties similar to natural peatlands. Techniques to improve moisture retention during the transplant process and increase water holding capability of the restored Sphagnum layer have been identified as an area of bog restoration that requires more research. Samples were collected from plots fertilized with six different nitrogen treatments at Mer Bleue Bog in Ottawa, Canada. Net CO2 assimilation, fresh weight, dry weight, water content, and dissolved nutrient measurements were made to determine the potential effectiveness of incorporating nitrogen fertilization into the North American approach to peatland restoration. High levels of nitrogen fertilization exerted deleterious effects on individual morphology, growth density, water holding and retention capacity, CO2 assimilation, and nutrient dynamics and decomposition. Fertilization with 1.6 g m-2 yr-1 of ammonium has the potential to ameliorate water retention capacity through more robust individual morphology and denser growth patterns and increases carbon assimilation and photosynthetic capacity. The results indicate integrating low levels of ammonium fertilization into bog restoration techniques can potentially increase restoration success., water content, carbon dioxide assimilation, growth density, peatland restoration, ammonium, nitrate
This research project evaluates the outcomes of returning prescribed fire to endangered Garry oak meadows as a restoration treatment. This project was done in partnership with Parks Canada and involved a case study on a three-year post-burn site on Tumbo Island in the Gulf Islands National Park Reserve. Soil chemical properties were analyzed three years post burn in the summer of 2019 and compared to pre and post-burn vegetation survey results. Analysis identified beneficial changes in soil chemistry still present three years post treatment. Invasive species occurrences increased across the site, regardless of treatment, and around half of the invasive species occurrences were recorded on burn treatments areas in 2018. Prescribed burns on shallow soil Garry oak meadow sites showed beneficial outcomes for soil chemistry, reduced conifer encroachment, increased diversity and Arbutus (Arbutus menziesii) seedling recruitment. These findings aid in determining restoration plans for shallow soil Garry oak meadows, highlighting the numerous benefits from prescribed fire, while also suggesting that additional treatments in conjunction with prescribed fire will be needed to control invasive plants when planning to restore these ecosystems., shallow soil, Garry oak meadows, restoration, prescribed fire, soil nutrients, invasive plant species
Prescribed burning and hand-pulling are used to manage invasive plants but treatments can deferentially affect species. My objective is to determine the effect of time-since-burning and hand-pulling on stem density and growth of Centaurea stoebe (spotted knapweed) and Linaria dalmatica (Dalmatian toadflax). Prescribed burns occurred in March 2015 and 2016, while hand-pulling occurred in April and May of 2017. I conducted vegetation surveys in May, June, and July 2017. Growth rates differed among treatments and by species. Centaurea stoebe was not detected in the prescribed burn treatments. Hand-pulling increased stem density of C. stoebe, but individuals were smaller and 60% remained as basal rosettes compared to control. Linaria dalmatica were significantly taller in the burn treatments, and the stem density of L. dalmatica was greater in the prescribed burn and hand-pull treatments compared to control. The tallest L. dalmatica occurred in the 2-year post-burn site, indicating a time-since-burning interaction., invasive plants, prescribed burning, hand-pulling, Cetaurea stoebe, Linaria dalmatica
Assessing restoration success for pond-breeding amphibians frequently focuses on hydrology, water quality and vegetation, while neglecting the requirements of amphibians that use the restored areas for breeding. Both biotic and abiotic conditions can influence oviposition-site selection of amphibians that do not provide parental care. This study examines how vegetation structure and abiotic variables affect oviposition-site selection by amphibians. The goal of my study was to better understand the requirements of pond-breeding amphibians. In 2017, I surveyed egg masses in four ponds at the Sunshine Coast Botanical Garden in Sechelt, B.C. I identified 667 egg masses of four native amphibian species that varied in abundance and species richness among ponds. I recorded five biotic variables (i.e., vegetation cover, vegetation type, stem density, stem diameter, and canopy closure) and two abiotic variables (i.e., water depth and solar radiation) at egg-mass sites and random sites where no egg masses were detected. Logistic regression analysis with backward elimination revealed that stem count (p = 0.008) and water depth (p = 0.0001) significantly influenced oviposition-site selection. The results also showed that higher stem density and shallower water depth increased the likelihood of egg masses being present. My study indicated that quantifying stems in the water column characterized vegetation density better than estimating percent cover of vegetation. Shallow areas that have structurally complex vegetation might provide an advantage for the offspring by increasing refuge, food resources, and favourable thermal conditions for egg development. Hence, restoration projects could incorporate vegetation structure and shallow areas in their pond designs to potentially increase the abundance and diversity of amphibian communities, thereby contributing to successful restoration projects., ecological restoration, amphibians, oviposition, Rana aurora, Pseudacris regilla, Ambystoma gracile, Amystoma macrodactylum, vegetation structure, abiotic variables
In the Fraser River Estuary of British Columbia, tidal marshes have been receding and converting into unvegetated mudflats since the 1980s. While there are many hypotheses for this recession, the effect of avian herbivory is poorly understood. This study assessed how Canada Goose (Branta canadensis) and Snow Goose (Chen caerulescens) herbivory affected cover of tidal marsh vegetation that was comprised mainly of three-square bulrush (Schoenoplectus pungens) in the Westham Island tidal marsh. I conducted two field-based exclosure experiments, marsh edge and mudflat, that used exclosure plots to reduce specific goose herbivory in a randomized block design. Each experiment consisted of four blocks each of which was comprised of four treatments: open to goose herbivory, excluded all goose herbivory, primarily excluded Canada Goose herbivory, or primarily excluded Snow Goose herbivory. The marsh edge experiment used exclosures centered on the vegetated edge of the marsh, while the mudflat experiment was conducted in the unvegetated mudflat and were transplanted with S. pungens. Based on results from July to October of 2020, percent cover of tidal marsh vegetation was about 20% lower in plots open to Canada Goose herbivory versus those that excluded geese. Snow Goose herbivory could not be accurately assessed as they arrived when S. pungens were dormant. Thus, deterring goose herbivory may be an important consideration for land managers in restoring tidal marshes. Additionally, I compared percent cover from drone-derived remote sensing to traditional ground-based visual estimates of percent cover of S. pungens in the tidal marsh. One per month, from July to October of 2020, I used a drone to take photos of the exclosures from the previous experiments, and used pixel counts to calculate the percent cover of S. pungens. I then used a t-test to compare the drone-derived percent cover to the ground-based estimates and found no significant difference (t = 0.58, p = 0.56). I then plotted a linear regression model and found a strong correspondence between both methods (R² = 0.99, p = 1.3e-139). So, remote sensing using drones appears to be an effective alternative to visual estimates of percent cover of tidal-marsh vegetation in the Westham island tidal marsh., Tidal marsh recession, Goose herbivory, Canada Goose, Snow Goose, Schoenoplectus pungens, Drones
Research on estuaries has increased in recent years, however, the effects of logging on estuaries and the effects of estuary habitat loss on Chinook salmon (Oncorhynchus tshawytscha) in the Pacific northwest is limited. To address habitat loss associated with logging, I used an extensive aerial photo record for Tranquil Creek estuary and an unlogged control to analyze changes in salt marsh area, elevation and volume, supplemented with a grain size distribution analysis.
While I failed to find evidence of a difference between a logged and an unlogged estuary, some negative trends in salt marsh area and elevation observed over the observational period were indicative of changes that are unfavorable for juvenile Chinook salmon. Analytical methods presented here to assess changes in two remote coastal estuaries has contributed to the current knowledge on the effects of logging on estuarine ecosystems in coastal BC and provide tools for innovative estuary habitat restoration., aerial photograph analysis, Chinook salmon (Oncorhynchus tshawytscha), salt marsh, estuary restoration, logging, sediment
Spotted knapweed (Centaurea stoebe) is a non-native invasive forb found throughout North America that suppresses native vegetation and reduces biodiversity. The designation of Blakiston Fan (Waterton Lakes National Park, Alberta) as critical habitat for the endangered half-moon hairstreak butterfly (Satyrium semiluna) brought forward concerns of the effects of knapweed management practices on the hairstreak and its native larval and nectar host plants. This pilot study used a randomized complete block design to examine the within-season change in cover of spotted knapweed and silky lupine (Lupinus sericeus) in response to herbicide application and two timings of manual removal (i.e., mid-June and late-July). This study also examined changes in the vegetation community and relative abundance of hairstreak butterflies across the fan. Significant treatment effects (p= 0.006, f3, 12= 6.89) were seen in the change in percent cover of spotted knapweed two weeks post-treatment between herbicide and control plots. There was no significant difference in the change in lupine percent cover among treatments (p= 0.075, f3, 12= 2.96). Cover of native host plants and hairstreak abundance were greatest in the south fan. Increases in knapweed cover were lowest in the south fan. Based on these results, a triaged management plan was recommended with restoration efforts focused on the south fan. Recommendations for the south fan include selective herbicide application to limit spotted knapweed distribution, closure of horse trails, and a native planting and seeding experiment. Management of the north and central fan was recommended to focus on the control of knapweed monocultures through intensive herbicide application and establishing biological control agents for long-term control. Further research of the hairstreak lifecycle is needed to understand the primary mechanism of decline, as well as, research into the response of native nectar host plants to knapweed control. Monitoring the response of the vegetation community and relative abundance of hairstreaks following the Kenow fire of 2017 is key in prioritizing restoration actions for Blakiston Fan., vegetation mapping, species at risk, host plant, invasive species, ecological restoration, Aminopyralid
Amphibian species are globally at risk, with a leading cause of decline attributed to habitat loss and fragmentation. The northern red-legged frog (NRLF) is one such species and listed as a Species of Special Concern by the Species at Risk Act. The Sunshine Coast Wildlife Project is creating new wetland habitat on the Sechelt Peninsula. In this research, I provide a tool to explore the relative effects on the functional connectivity of different potential restoration sites. A habitat suitability model (HSM) was created to describe the landscape in terms of conductance, or ease of movement for NRLF. Using this conductance map, I analysed the functional connectivity between wetlands by using Circuitscape, a software grounded in circuit theory. Three potential restoration options were compared against the existing landscape. Of the three options, one had a much greater effect in increasing the overall wetlands and its connectivity to the existing network of wetlands., Functional connectivity, wetland habitat restoration, northern red-legged frog (Rana aurora), circuit theory, Circuitscape, habitat suitability model (HSM)
Prairie dogs (Cynomys ludovicianus) are considered a keystone species due to their ecological role in maintaining the prairies. In Canada, they are federally listed as a threatened species. This study was conducted to identify the limiting factors to the expansion of prairie dog colonies in Grasslands National Park, Saskatchewan. I tested different hypotheses to compare landforms, vegetation, and soil characteristics in three treatments: consistently occupied (Consistent), inconsistently occupied (Inconsistent), and never occupied (Buffer) by prairie dogs. I sampled four prairie dog colonies (blocks) from 17 July 2019 to 28 August 2019 using a randomized complete block design. I used ANOVA to test variables for significant differences among treatments. My results showed that hills, water channel, shrublands, grass cover, shrub cover and vegetation height classes (>30 cm) were significantly higher (p <0.05) in Buffer compared to Consistent and Inconsistent. Shrubs and tall vegetation should be mowed down to enhance the expansion of prairie dog colonies for restoring their population., restoration, prairie dogs, Cynomys ludovicianus, colony expansion, barriers, habitat use
A bog is a type of wetland with a high water table, acidic soil and is nutrient poor. Camosun Bog is the oldest bog in the Lower Mainland of British Columbia, and remained undisturbed until development of the surrounding residential neighborhood caused changes to its groundwater conditions, threatening its current persistence. The goal of this study is to provide an updated examination of Camosun Bog’s groundwater conditions and to discuss relevant bog restoration measures. Groundwater elevation and chemistry (pH, conductivity, nitrogen and phosphorus) were monitored for several months in 2019. Results indicate that current groundwater elevations are lower in Camosun Bog than they were thirty years ago, especially in the north and northeast regions. Locations in the north and center parts of the open bog experienced groundwater nitrogen enrichment and higher pH, indicating that raising the water table should be the main goal of restoration for Camosun Bog.
A full composition study of some key Fraser River foreshore marshes, Boundary Bay, Brunswick Point, Westham Island, Lulu Island, and Sea Island, had not been done in several decades, during which a large-scale marsh recession event occurred at two of the marshes. The vegetation composition is measured in this study with relation to soil water, soil pore water salinity, and elevation. The results in this study show a shift in the vegetation composition in some areas of the Lulu Island marsh, with the other marshes remaining relatively similar to historical data. The plant species’ tolerance to soil water, soil salinity, and elevation vary in each marsh, illustrating the need for individualized restoration plans for each marsh. Conserving and restoring these marshes is critical in light of the many changes in the Fraser River delta, including sea level rise, increased geese populations, altered sediment regimes, and urbanization., Fraser River, brackish marsh, salt marsh, vegetation composition, salinity, elevation
Coastal wetlands are an important ecosystem in the Great Lakes basin, providing spawning grounds and warm-water refuge for numerous fish and benthic invertebrate species during cold water upwelling events. Urbanization along the northwestern shore of Lake Ontario has led to a depletion of coastal wetlands, replacing them with artificial embayments. Three artificial embayments, the Credit River estuary, and one coastal marsh in Mississauga, ON were studied to determine if the artificial embayments function as warm-water refuge during upwelling events. Temperature loggers were placed in each study site and temperature was recorded every 15 minutes from July to October 2017. Upwelling events were isolated from the data, and frequency, magnitude, and duration of upwelling was determined. Most study sites had a frequency of 4 upwelling events throughout the study period. The average duration of upwellings varied from 30 to 70 hours, and the average temperature change ranged from -7.1ᵒC to -11.9ᵒC. All of the study sites seemed to buffer upwellings by reducing the magnitude of temperature change and increasing the duration of upwelling events to varying degrees. These results will inform the creation of future wetlands, restoration of existing embayments, and conservation of Great Lakes coastal wetlands., ecological restoration, coastal embayments, coastal marsh, upwelling, warm-water refuge, Lake Ontario