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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Determining the Accuracy of the Beaver Restoration Assessment Tool for Identifying North American Beaver (Castor canadensis) Habitat in the Central Interior Cariboo Region of British Columbia
Perennial watercourses in British Columbia are becoming intermittent from climate change. North American beaver (Castor canadensis) dams retain perennial flow while providing other ecosystem services. The Beaver Restoration Assessment Tool (BRAT) estimates a stream’s dam capacity by evaluating the vegetative, physical, and hydrological habitat. This research project surveyed 15 streams in the Cariboo region to assess the accuracy of the BRAT’s outputs. Climate data were used to model changes in flow. Overall, the BRAT outputs generally correlated with field measurements. However, the non-vegetation outputs contributed minimally to dam capacity, and higher dam capacity did not always indicate higher habitat quality. Climate projections also indicate most streams will lose nival flow by 2041-2071. Therefore, using the BRAT with other models can determine both dam capacity and overall habitat quality to increase successful beaver restoration chances. When vegetation and physical stream conditions are met, higher watershed/channel size may indicate higher-quality habitat.
Drivers of humpback whale movement in Boundary Pass, British Columbia
The Salish Sea is critical habitat for several whale species including the humpback whale (Megaptera novaeangliae). Boundary Pass is part of the Salish Sea and connects the Pacific Ocean to several commercial shipping ports in the Pacific Northwest Region of North America. Since 1997, the number of Humpback whales continues to increase in this area, meanwhile the number of vessels is also increasing such that Boundary Pass is among the busiest shipping routes in the region. This high vessel traffic in the area leads to acoustic disturbances that degrades whale foraging opportunities for humpback whales. Commercial vessels transporting goods through whale habitat causes an increased risk of vessel collisions with humpback whales. Humpback-whale movements in Boundary Pass was recorded through systematic scan surveys conduction from a vantage point between June and August. Whale occupancy was compared to oceanographic variables and vessel presence. We found humpback whales were most likely to be present during ebb tides of speeds of -2 m/s under the influence of low tides and also whales were active in areas overlap with shipping lane in the area. Based on our founding in the area about humpback whale connection with biophysical properties of region I hypothesized that whale distribution in area and it relation to low tide and ebb current is most probably under the influence of food abundance in those periods of time. This study concludes with policy recommendations for improving humpback whale foraging grounds by reducing acoustic harassment and risk of ship strikes in the Boundary Pass., Humpback whale, movements, oceanographic variables, Boundary pass, Salish sea, Vessel strike, tide, currents, SST, salinity
Ecocultural restoration of a Coastal Root Garden on Tl’chés (Chatham Island), B.C.
Tl’chés is the Lekwungen name for the Chatham Islands — an archipelago located southeast of Victoria, British Columbia. Tl’chés is a central place in the traditional territory of the Lekwungen peoples, and today it is reserve land of the Songhees First Nation. This landscape was traditionally managed by prescribed burning and the cultivation of native plants. However, in the early 1950's, Lekwungen peoples left the archipelago, due to a lack of potable water and since then, the landscape has degraded drastically. The introduction of non-native plants has resulted in threats to the ecological, cultural resilience, and diversity of the landscape. My research focuses on developing a restoration plan for springbank clover in the coastal root garden. My restoration approach focuses on incorporating a Songhees-informed approach to restoration by integrating past practices and knowledge with the aim of answering: how to best restore the springbank clover population on Tl’chés?, Eco-cultural restoration, coastal root gardens, traditional ecological knowledge (TEK), Songhees First Nation, cultural keystone place (CPK)
An ecological restoration plan for a weedy field at the University of British Columbia Okanagan
Grassland ecosystems are rare, in decline, and support a multitude of at-risk species in British Columbia. At the University of British Columbia Okanagan in Kelowna BC, a 3.3 ha site at the entrance of the campus is outlined as Okanagan grassland in campus design plans but currently lacks native bunchgrass communities. The goal of this restoration plan is to return grassland plant communities to the site despite the pervasiveness of noxious weeds. I characterised site conditions through soil and vegetation surveys. Restoration recommendations include managing noxious weeds through mowing, hand-pulling and some herbicide application. The site will be replanted with bunchgrass vegetation, two pockets of ponderosa forest, and two types of shrub communities. A walking path, signage, and two xeriscape gardens will also be included to control human use of the landscape. Long-term monitoring will be incorporated into classroom curricula to tie monitoring to learning opportunities., Grassland, exotic plants, Noxious weeds, urban restoration, restoration plan
The effect of prescribed burns on soil characteristics and plant communities in Garry Oak ecosystems. A case study on a three-year post-burn site on Tumbo Island, Gulf Islands National Park Reserve
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
The effects of tree thinning and broadcast burning on the quality of ungulate winter range: a case study within a Southern Interior Forest in British Columbia
Food limitation on ungulate winter range (UWR) has been a suspected factor in the regional declines of Odocoileus hemionus (mule deer) in the Pacific Northwest. Accordingly, enhancing browse resources in this critical habitat is increasingly recommended. At a dry forest site in Southeast B.C. called Fiva Creek (IDF dm1), I investigated the effects of two commonly prescribed methods for enhancing browse production: tree thinning and prescribed burning. Treatments were implemented between 2005–2008 and included three levels of thinning (all burned) and control areas (uncut and unburned). The response variables I measured included browse cover, canopy closure, security cover, visibility, and pellet abundance. I also evaluated browsing pressure on the indicator plant, Saskatoon (Amelanchier alnifolia). Using linear mixed-effects ANOVA tests, I assessed how thinning (with follow-up burning) influenced forest and vegetation properties. There was no evidence of a treatment effect on browse production; however, browsing pressure was very high across the site (i.e., > 80% of A. alnifolia twigs showed evidence of browsing). Additionally, canopy cover was below recommended levels in all thinned treatments. My results suggested that restoration treatments actually diminished the quality of UWR at Fiva Creek. Further investigations are needed to develop effective UWR restoration methods., Mule deer, ungulate winter range, thinning, prescribed fire, restoration ecology
Exploring the relative effects of different wetland restoration sites on functional connectivity for the northern red-legged frog (Rana aurora)
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)
Factors limiting the expansion of black-tailed prairie dog colonies at their northern extent
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
Groundwater elevation and chemistry at Camosun Bog, British Columbia, and implications for bog restoration
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 historical marsh vegetation composition comparison between five Fraser River foreshore marshes
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
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 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

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