Master of Science in Ecological Restoration Applied Research Projects | BCIT Institutional Repository

Master of Science in Ecological Restoration Applied Research Projects

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Identifying temporal trends and mechanisms for successful reforestation on former agricultural land
This study investigates the outcomes of restoration efforts completed on retired agricultural land in Southwest Ontario. Sites acquired by the Nature Conservancy of Canada were planted to kickstart succession to native deciduous forests, but the results of the plantings are mixed. Analysis of soil conditions indicated that low levels of soil organic carbon were correlated to low water content and high density unfavourable for plant growth. Analysis of remotely sensed imagery was done to assess and compare vegetation cover to reference conditions at Walpole Island First Nation. Analysis revealed that successful restoration was dependent on multiple soil characteristics, but conditions correlated to higher total organic carbon favoured greater vegetation cover. Remote sensing data revealed that succession towards tree canopy development was accelerated compared to passive restoration, and a shaded understory was established approximately 8-12 years following restoration. Future work can expand on succession and the effects of other restoration treatments., Soil, Reforestation, NDVI, Agriculture, Restoration, Secondary succession
The impact of roadway mortality on a long-lived freshwater turtle, Chrysemys picta bellii
Road mortality poses a significant threat to freshwater turtles globally, including the western painted turtle (Chrysemys picta bellii). Even low levels of road mortality can severely impact the long-term survival of these long-lived reptiles. While mitigation infrastructure is employed to reduce mortality, its effectiveness may vary depending on the location and species involved. Population viability analysis can be a valuable alternative for wildlife managers to assess the viability of the populations they monitor and the potential impact of management decisions, but are most useful when data from target populations is available. This research project aimed to evaluate the long-term persistence of a rural western painted turtle population experiencing road mortality. The study first investigated the effectiveness of a turtle tunnel and drift fencing in reducing road mortality. Parameters derived from the population were then used to model the long-term viability of the turtle population in the program Vortex under various scenarios of ongoing road mortality. This study analyses three years of mark-recapture, ratio telemetry tracking, and road mortality surveys done by contractors and summer hires of the Ministry of Water, Land, and Resource Stewardship at Baynes Lake, BC. The turtle population was estimated to be 1,451 (SD= 75) individuals, with a female-biased sex ratio (1.5 females: 1 male). Only a quarter of sexually mature females were found to be gravid in a given year, with gravid females laying only one clutch. Subadult and adult survivorship were calculated using the same dataset employed for the population estimate, resulting in a survivorship rate of 96.4% (SD = 1.3%) per year. Radio telemetry was used to assess the number of road crossings made in a given year. Gravid females were found to make a higher average number of road crossings (1.6 road crossings per season) than males (0.1 road crossings per season) or non-gravid females (0.7 road crossings per season). In 2021, an under-road turtle tunnel was installed in Baynes Lake, followed by the installation of drift fencing in the spring of 2023. Over time and after the implementation of drift fencing, more turtles were observed encountering the installed turtle tunnel. However, evidence regarding the complete traversal of the turtle tunnel was not conclusive. Before the installation of the turtle tunnel, casual community-led surveys in 2021 estimated a mortality rate of 1% of the population. Mortality rates, calculated over the duration of the survey periods, decreased after the installation of the turtle tunnel (0.1 mortalities per day in 2022) and further decreased after drift fencing was installed (0.03 mortalities per day). The long-term viability of the Baynes Lake population was modeled in Vortex, with additive road mortality modeled as a percentage loss of the population. The road mortality rate of 1% additive mortality, seen before road mortality reduction strategies, resulted in a 60% decrease of the initial population after 100 years. This indicates that even low levels of additive adult road mortality can lead to declines in the Baynes Lake western painted turtle population. Sensitivity testing of the model indicates that the Baynes Lake population is highly sensitive to changes in adult/subadult and juvenile mortality. Pre-mitigation mortality levels had the potential to dramatically impact the population of Baynes Lake. It is crucial to acknowledge and address what may appear to be relatively low levels of roadway mortality in rural areas, as even these seemingly modest rates can have a significant impact on western painted turtle populations., Western painted turtle, Chrysemys picta bellii, roadway mortality, population viability modeling, population estimate, scavenge rate
The impacts of exotic Typha on benthic invertebrate communities in the South Arm of the Fraser River Estuary
In recent decades, the exotic cattail Typha angustifolia and its hybrid Typha x glauca have invaded the Fraser River estuary. The impacts from this invasion on benthic macroinvertebrate communities, however, are yet to be studied. Macroinvertebrates play important roles in food chains, trophic dynamics, and nutrient cycling and are potentially at risk from this invasion. In this study, I compared the benthic invertebrate communities between exotic cattail stands and native vegetation stands at 25 paired sites. Sediment cores were analyzed for invertebrate abundance, biomass, and Shannon Wiener diversity index, and it was found that biomass and abundance were lower in exotic cattail when compared to native vegetation, however, there was no difference in diversity. Given the proximity to side channels, tidal inundation time would be a logical explanation for the differences in the benthic communities; however, it was not found to be a significant predictor. Given the invasive nature of exotic cattail and the correlations that were found, cattail should be removed in restoration projects where possible., Fraser River, Typha x glauca, Estuary, Invasive species, Typha angustifolia
Impacts of roads and cranberry agriculture on bog wetland hydrology with restoration recommendations for Langley Bog
Bog wetlands store a disproportionate amount of carbon for their size, making their conservation an important part of climate change mitigation. The goal of this project is to investigate how roads and agriculture impact the hydrology and vegetation composition of Langley Bog and to provide restoration recommendations. Langley Bog, in Langley Township, BC, is a formerly mined peatland with a fill road running through the center and surrounded to the north and west by cranberry farms. From November 2020 to November 2021, depth to water table and pH were measured monthly at nine wells. Twelve vegetation transects were completed in July 2021. Sites adjacent to the road were correlated with a decrease in summer water level, while sites adjacent to the cranberry farms were correlated with an increase in spring pH levels. A positive relationship was found between an increase in water-table level and percent cover of wetland obligate species. Roads may be lowering the water table through subsidence and drainage. The cranberry farms may be increasing the pH through the deposition of fertilizer. These impacts may have been exacerbated by the unusually dry 2021 summer season. To raise the water table, tree and road removal is recommended to restore lateral flow and decrease evapotranspiration. Culverts installed under the primary fill road will provide additional hydrologic connectivity. Building a berm at outlet points will also help prevent water loss, keeping a higher water table. To increase carbon sequestration, Sphagnum mosses are to be reintroduced to denuded areas in Langley Bog. Tree removal will help in moss establishment by maintaining open bog conditions free from shading. Existing rare ecosystems present in Langley Bog would benefit from the removal of point source pollutants and invasive species on the site. Given the urgency of climate change, restoring the functionality of Langley Bog and protecting the existing stored carbon is a practical and achievable way to move Metro Vancouver a step closer to carbon neutrality., peatlands, ecological restoration, water levels, pH, sphagnum
Investigating biotic interactions as limiting factors of burrowing owl (Athene cunicularia) population recovery in British Columbia
Burrowing owls (Athene cunicularia) were considered extirpated from British Columbia by 1980 and still require active management to sustain a breeding population. My research objective was to investigate if predator-prey interactions limit the survival and reproductive output of burrowing owls in British Columbia. Wildlife camera photographs and direct observations were used to assess survival, prey return rate and availability, and predator occurrence rate at six different conservation-breeding release sites across two regions and three reproductive-output levels. Ten out of the twelve nests studied successfully produced at least one juvenile owl that is presumed to have survived to the end of the 2023 breeding season. Results indicate that there may be regional differences in reproductive output and prey availability but not predator occurrence. Neither prey availability nor predator occurrence were significantly correlated with burrowing owl reproductive output, although some prey metrics were trending towards significance. However, competition over food resources with other species may be more detrimental to burrowing owls than previously thought, particularly over vertebrate prey items. Relationships between burrowing owls and the other species they interact with in British Columbia are complex; predator-prey dynamics alone do not account for the variability of burrowing owl success rates across the region. Active management such as supplemental feeding and anti-competitor deterrents at the entrances to burrows may be necessary to support this endangered species until it has reached more sustainable population numbers., burrowing owl, endangered species, wildlife management, predator-prey, trail cameras
Investigating bull kelp decline in Saturna Island Interim Sanctuary Zone
Kelp is an ecologically, economically, and culturally important species that is facing global declines. This pilot project investigated if declines in Bull Kelp in the Saturna Island Interim Sanctuary Zone could be attributed to increased herbivory by sea urchins, and/or thermal stress caused by increased ocean temperatures. In areas where sea urchins were excluded, bull kelp was more abundant and in areas where sea urchins were not excluded, heavy grazing was observed. Throughout the summer 2023 study period, sea surface temperature did not exceed bull kelp’s adult or gametophyte thermal tolerance. Restoration of this site should include methods to reduce sea urchin herbivory, while carefully considering cultural and ecological implications., macroalgae, sea urchin, bull kelp, kelp restoration, herbivore exclusion
Investigating regeneration in a raised ombrotrophic bog after peat extraction
Burns Bog is a raised ombrotrophic bog in Delta, British Columbia and faced with myriad disturbances. This study is focused on the impact and restoration of peat extraction by the Atkins-Durbrow Hydropeat method. Depth to water table, relative abundance and distribution of vegetation, and the degree of peat decomposition at consistent-depth intervals were investigated to elucidate the status of passive and active ecological restoration in three fields previously harvested for peat approximately one decade apart and compared to a fourth unharvested field. Summary statistics, Redundancy Analysis, and regression were used to compare restoration status and trends in hydrology, vegetation composition, and peat accumulation. A lag period between cessation of harvest and implementation of restoration, coupled with rapid anthropogenic climate change, serve as impediments to restoration here. Intervention in the form of improved rainfall retention, assisted recolonization, and the introduction of nurse species are recommended to improve bog function and resiliency., Atkins-Durbrow Hydropeat method, Ditch blocking, Ecological restoration, Peat extraction, Raised ombrotrophic bog, Burns Bog
Investigating the role of elevated salinity in the recession of a large brackish marsh in the Fraser River estuary
At least 160 ha of the Sturgeon Bank low marsh in the Fraser River delta died off between 1989 and 2011. Humans have heavily modified the Fraser River estuary since the late 1800’s, including installing a series of jetties throughout the leading edge of the delta to train the course of the river. I established a reciprocal transplant experiment to determine the role of elevated salinity in the marsh recession and generate information needed to eventually revegetate areas of receded marsh as part of an intergovernmental collaboration to investigate the causes of this marsh recession. I propose specific actions to better monitor, maintain, and restore the Fraser River delta foreshore brackish marshes in response to ongoing ecological degradation of the estuary. The predicted effects of climate change and sea-level rise may cause us to rethink options for restoring the Sturgeon Bank marsh., Restoration, Fraser River, Schoenoplectus pungens, Reciprocal transplant experiment, Marsh recession, Brackish marsh
Mapping floodplain fish habitat in the heart of the Fraser River and restoration options for impacted attributes on selected large mid-channel islands
The purpose of this project is to develop an ecological restoration plan for degraded habitats on mid-channel islands in the lower Fraser River. The study focuses on Herrling, Carey, and Strawberry islands, large mid-channel islands located in the gravel reach between Mission and Hope, British Columbia. These islands are known to be critical off-channel rearing habitat for many fish species including the threatened White Sturgeon (Acipenser transmontanus) and interior and lower Fraser watershed Chinook Salmon (Oncorhynchus tshawytscha) populations. These islands are also home to many riparian plant and animal species. The flood-pulse concept (FPC) states that seasonal fluctuations in water levels for streams such as the Fraser River contribute substantially to the ecological function of the floodplain ecosystem where this phenomenon occurs. This often results in improved growth and survival rates for fish species that rely on a laterally-moving littoral zone of inundation. This phenomenon is thought by many to be the key to a properly functioning ecosystem in the lower Fraser River. Using a Digital Elevation Model (DEM) for the Fraser River between Hope and Mission, British Columbia, freshet flows (high water elevations) are presented to define the spatial extent of over-bank watering of Strawberry, Carey and Herrling islands. This over-bank watering provides lateral connectivity to floodplain islands. Based on extensive sampling in other studies, this lateral movement results in the creation of high-quality juvenile fish rearing habitat. A restoration plan is presented for those areas of Strawberry, Carey and Herrling islands degraded by recent land clearing for agriculture where they overlap sections defined as fish habitat from the spatial analysis., gravel reach, mid-channel islands, floodplain fish habitat, flood pulse concept, juvenile Chinook Salmon, lower Fraser River, White Sturgeon
A meta-analysis of North Shore streams: maximizing the effect of installed rain gardens through strategic placement
A meta-analysis using pre-existing data was done for streams in the North Shore of Vancouver, British Columbia. Parameters considered were chemical concentrations from stormwater input including: heavy metals concentrations (Copper (Cu), Zinc (Zn), Cadmium (Cd), Lead (Pb)) and nutrient concentrations (Nitrate (N03-) and Orthophosphate (P04 3-))_ Chronic toxicity guideline exceedance based on the British Columbia Approved Water Quality Guidelines was found in all 94% of stream systems for Cu and 44% of stream systems for Zn. Heavy metal concentrations were found to be positively correlated with percent impervious surface cover in the watershed, with the strength of the correlation being metal-dependent. Three sites within the study had the highest levels of both Cu and Zn. These watersheds (Upper Keith Creek, Maplewood Creek, and Mackay Creek) were prioritized for rain garden installation. Rain garden building specifications to remediate for Zn and Cu were recommended and included addition of mulch layer, minimum depth of topsoil (30 cm), and vegetating with plants with high potential for biofiltration and/or phytoremediation., Impervious surface cover, Stormwater, Rain garden, Green infrastructure, Heavy metal analysis
A mitigation plan for salmonid spawning habitat in the Lower Seymour River, North Vancouver
Salmonids are a very important species to British Columbia and the Pacific Northwest. They are an icon of British Columbia’s heritage and they hold many ecological, economical, recreational, and cultural values. Unfortunately, Pacific salmonid populations have been declining over the last century due many reasons including degradation of freshwater habitat used for spawning and rearing. This degradation is largely due to expanding urbanization and the installation of dams for flood control, hydropower and water supply. The Seymour River is a mountainous river located in North Vancouver. Over the past century, this river has been subjected to many anthropogenic activities that have cumulatively altered the natural flow and sediment regime. The Seymour Falls Dam, located in the middle of the watershed, intercepts gravel transport from the upper watershed into the lower reaches. This combined with the intense channelization within the lower 4 km of the river, which has created conditions incapable of gravel deposition and retention, has led the lower reaches to become gravel deficient. This gravel deficiency has caused the degradation of traditional spawning grounds of chum (Oncorhynchus keta), and pink salmon (Oncorhynchus gorbuscha). This study aims to: 1) determine if there is a gravel deficiency for chum and pink salmon spawning in the lower 1.5 km reaches and, 2) provide recommended mitigative treatments of gravel addition to increase suitable spawning area, and therefore increase salmon productivity of the Seymour River. A site assessment was conducted on the lower 1.5 km of the Seymour River and included sampling of the five key parameters that define spawning habitat (i.e., water depth, velocity, dissolved oxygen, water temperature and substrate). A particular focus was given on analysing the substrate as it was expected to be deficient for spawning due to the predetermined conditions in the watershed such as the dam and the channelization. Results of the site assessment confirmed that substrate is the limiting factor for chum and pink salmon spawning in this area as the bed surface is composed of large cobbles and boulders too large for these specific species to move to dig a redd. Therefore, a xi mitigation plan of gravel addition is proposed to increase spawning habitat and conserve these salmon runs. Two gravel placement sites were selected between Mt. Seymour Parkway and Dollarton Bridge. A gravel mobility analysis determined that suitable-sized gravel will not be deposited or retained naturally on the channel bed due to the slope and water depth at high flood events. Therefore, gravel catchment structures are proposed to dissipate energy, thereby promoting deposition and reducing scouring. Each site contains a different design tailored to the specific characteristics of that reach. To retain gravel, spurs composed of the surface cobbles and boulders are proposed along with imbedded gravel pads composing of suitably sized gravel brought in from a local source. In total these two sites could provide about 1,925 m2 of additional spawning habitat which could support 209-836 pairs of chum or 3,208 pairs of pink salmon. Through long-term monitoring, this project in the Seymour River could provide strategies of gravel placement in large, urbanized, gravel-deficient rivers, in which current research is limited. Many rivers in North Vancouver (i.e., Capilano River, Lynn Creek, McKay Creek and Mosquito Creek) may be experiencing a gravel deficit similar to the Seymour River, and the strategies outlined in this project could be adapted to the specific conditions of those rivers. The cumulative effect of adding spawning gravel in each river within the Burrard Inlet, as well as elsewhere in the Pacific Northwest, could reduce stress in their freshwater phase and aid in rebuilding salmon populations from their precipitous decline in which they are on currently on track for. The strategies provided will also become important as more rivers become sediment deprived due to the construction of hydropower dams in response to a change from fossil fuels to renewable energies as climate change continues. The need for more innovative habitat mitigation strategies will be necessary to keep salmon from becoming a relic of the past.
Modelling potential impacts of sea level rise on Siwash Island
Siwash Island is a tidal marsh situated at the southern end of the Widgeon Marsh Regional Park Reserve, Coquitlam, British Columbia (BC). The numerical model MarshMorpho2D was used to depict the evolution of marsh under various scenarios of sea level rise (SLR), suspended sediment concentration (SSC), and tidal range (TR) over the next 80 years. Changes in SLR and TR substantially impact the island’s morphology. Higher TR and SLR cause higher inundation and erosion rate, resulting in loss of vegetation, elevation, and habitat across the island. The model projection indicates that Siwash Island is likely to submerge within the next 80 years. The MarshMorpho2D model provides insights for policymakers and conservationists to develop adaptive strategies to mitigate the effect of SLR on coastal ecosystems., tidal marsh, numerical model, MarshMorpho2D, sea level rise, tidal range, suspended sediment concentration
Plant facilitation effects as a potential restoration tool in riparian ecosystems in Southwestern British Columbia
This study began to investigate potential facilitative effects among shrub species in riparian ecosystems in southwestern British Columbia. I ran two concurrent studies. Six plots for each of four treatments were established at the Coquitlam River Wildlife Management Area. The first two treatments compared the survival, growth, flowering, and herbivory rates of planted twinberry seedlings in plots where the shrub layer was removed to plots where it was not. The other two treatments compared the survival, growth, leaf loss, flowering and herbivory rates of snowberry plants in plots where the salmonberry upper shrub layer was removed to those where it was not. No significant differences between the measured parameters in any of the treatments were found. These results are discussed in the context of the riparian forest ecosystem and current facilitation theory. The results are then used to inform an ecological restoration plan for the Suwa’lkh School Forest., Facilitation, Riparian forests, Native vegetation, Symphoricarpos albus, Lonicera involucrate, Rubus spectabilis, Ecological restoration
A prey-based approach to restoration
Forestry in British Columbia’s old-growth forests has reduced critical foraging and breeding habitat for the coastal northern goshawk (Accipiter gentilis laingi) and restricted population growth. Now at-risk, efforts to recover this subspecies have focused on establishing suitable habitat and a well-distributed population within the province. However, regional diets and associated dynamics are also critical to goshawk recovery and remain poorly understood. Including a synchronous predator-prey recovery approach to current plans can bridge these knowledge gaps. A new model and methods were developed to translate prey biological requirements into structural surrogate features that could be parameterized and ranked within GIS software. Applying these ranks to known goshawk territories in the South Coast allowed for the visualization and quantification of areas with subpar predicted prey abundances. This provided insight on links between prey and forest structure and can be used to direct future restoration and research decisions for coastal goshawk prey-based recovery.
Re-establishing the historic fire regime to restore the Chittenden Meadow, Skagit Valley Provincial Park, British Columbia, Canada
Prescribed burning is being used by BC Parks as a restoration tool to maintain the ecologically unique Chittenden Meadow in Skagit Valley Provincial Park. Forest encroachment of conifers in the meadow, due to the absence of fire, has been an ongoing issue since the 1970s. BC Parks in partnership with the BC Wildfire Branch conducted prescribed burns in April 2003 and April 2021 to reduce forest encroachment into the meadow. In 2017, BCIT students re-established a series of plots to compare vegetation community changes with the 2003-2004 prescribed burn data. This data was compared to our 2021 findings. Continued long-term monitoring of the meadow will help to enhance our understanding of vegetation community changes following prescribed fires and will build upon a decade of existing data. The historical extent of the meadow remains unclear; therefore, we conducted a broad fire history study across ~275-ha of forest surrounding the Chittenden Meadow to better understand the area's past fire frequency and severity., prescribed burning, forest encroachment, vegetation community change, fire history study
Restoration of an urban creek water quality using sand and biochar filtration galleries
Stormwater runoff from parking lots often contains a variety of elements and compounds in different forms and concentrations that may pose risks to biota in receiving aquatic systems. Heavy metals including copper (Cu) and zinc (Zn), and polycyclic aromatic hydrocarbons (PAHs) are of particular concern in such runoff due to their prevalence, toxicity to aquatic organisms and persistence in the environment. The ability of a commercially available biochar to remove pollutants of concern through column treatments was assessed in this research. Factors including the pollutant’s concentration, total organic carbon (TOC), pH, and biochar particle size were considered. The biochar used in this study showed a significant heavy metals and PAH removal ability compared to sand, qualifying it as a potential substitute for sand in urban structural best management practices. Maximum percentage removal using biochar followed the order of naphthalene (NAP) > Zn > Cu. Regarding Cu and Zn removal, small biochar exhibited higher removal efficiency compared to medium biochar. In terms of NAP removal, both small and medium biochar exceeded sand with a five-fold percentage removal. However, biochar of different particle sizes had the same removal percentage., infiltration swale, biochar, parking lot stormwater, naphthalene, stormwater management, heavy metals, PAH

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