In Ontario, invasive Phragmites australis threatens to displace many species including the endangered species Sida hermaphrodita and Ammannia robusta. Germination and growth assays measured the effect of P. australis aqueous extracts from the leaves, rhizomes, and roots on S. hermaphrodita and A. robusta. Germination was inhibited by some of the treatments, but growth was not. The tissues inhibited germination differently for S. hermaphrodita (leaf> rhizome> root) compared to A. robusta (root> rhizome> leaf) indicating that the allelopathic effect was species-specific. However, the laboratory results show that allelopathic effects are weak. This result is consistent to the field study results showing an increase in S. hermaphrodita area and density over time. Results from this project inform management options by indicating which part of the plant needs to be targeted. In this case, all the tissues had some phytotoxic effects, indicating that biomass may need to be removed or long-term management implemented., Invasive Species, Species at Risk, Seed Germination, Seedling Growth, Allelopathy
Dikes and culverts have limited access to off-channel rearing habitats important to juvenile coho salmon (Oncorhyncus kisutch). This study assessed the success of a floodplain reconnection project in Squamish, BC, at providing rearing habitats. Recommendations on restoration priorities within the area were also provided. A single-season, multi-scale occupancy model was used to estimate the probability of occurrence and detection of juvenile coho during the summer. Regression models were used to assess water and habitat quality and identify relationships with juvenile coho metrics. Culverts were also scored for fish passage. The results of this study indicate that the reconnection project was overall successful. Coho non-detections occurred in areas with poor dissolved oxygen and culvert passage issues. Restoration actions should focus on improving water quality in these areas, and protection of areas of high CPUE. Positive relationships between stream productivity and coho metrics indicates the importance of future studies on macroinvertebrate supply., coho salmon, escape cover, rearing habitat, floodplain reconnection, urban channels, Mamquam River
This research project aims to assess the carbon sequestration dynamics of three tidal marshes under different environmental conditions in the Metro Vancouver region. By identifying the site conditions that influence carbon sequestration, areas can be prioritized, and restoration activities can be adapted to increase or maintains the marsh’s ability to do so. This project was done in partnership with Parks Canada and will contribute to a larger study of ‘blue carbon’ across British Columbia. For this project, I collected sediment cores from the eastern portion of Boundary Bay in Delta, BC, Brunswick Point in Ladner, BC, and a constructed salt marsh in Tsawwassen, BC, to assess soil carbon content and carbon stocks. Porewater salinity, vegetation data and depth measurements were collected at these sites as well. Percent carbon content ranged between 3.98 ± 1.48% and 5.78 ± 5.93% between the three marshes and the marsh carbon stock ranged between 93.95 Mg C and 2,994.51 Mg C. Across the three marshes, core carbon stock for the high marsh cores was found to be significantly higher than the core carbon stock for the low marsh cores, suggesting that marsh zonation influences carbon stock. The data analysis and literature review determined that vegetation and porewater salinity had the greatest influence on a marsh’s ability to sequester and store carbon. The results indicate that the high marsh with low salinities and a diverse plant community have the highest carbon sequestration potential. As marshes with conditions similar to that of the Boundary Bay marsh as well as polyhaline marshes should be prioritized for restoration. These findings will aid in the development and implementation of restoration projects to increase a marsh’s ability to sequester carbon., blue carbon, tidal marsh, carbon stock, British Columbia, coastal management, restoration, marsh restoration
Stream temperatures in the Pacific Northwest are increasing due to climate change, resulting in thermal stress for salmonids. Groundwater is a cooler source of water into streams, providing thermal refugia. The goal of this Applied Research Project was to identify groundwater input areas in the Tsolum River, using temperature loggers to trace the thermal signal of groundwater. A total of 28 water temperature loggers and 2 air temperature loggers were deployed within the watershed in the summer of 2019. Results showed that 12 sites may be influenced by groundwater input. Restoration/management actions such as riparian planting, gravel bar live staking, and restrictions on groundwater withdrawal are recommended to decrease stream temperatures. This study demonstrated that temperature loggers can be deployed within streams to identify areas of groundwater input. The identification of thermal refugia within the Tsolum River and other salmonid-bearing streams will help to protect salmonids from climate change impacts., climate adaptation, thermal refugia, Tsolum River, groundwater
Since the 1980s, at least 160 ha of marsh vegetation has died off in Sturgeon Bank and Westham Island, located within the Fraser River Estuary. Proposed causes for this marsh recession include sediment deficit, relative sea-level rise, increased salinity, and goose herbivory. At Westham Island, the loss of tidal marsh vegetation is locally distinct in that it occurs in a closed polygon shape versus along the leading edge of the marsh, suggesting that goose herbivory is a principal cause. Goose herbivory on tidal marsh vegetation has become a global problem as many geese populations are becoming hyperabundant. In the Fraser River Estuary, Canada goose (Branta canadensis) and snow goose (Anser caerulescens) numbers have been increasing exponentially. I conducted a field experiment, testing two novel goose herbivory deterrents at Westham Island’s foreshore tidal marsh: metal and snow fencing placed flat against the substrate. I used a randomized complete block design with six replicates and three treatments: metal fencing, snow fencing
and control (no fencing). Each treatment's effectiveness was assessed by monitoring changes in common three-square bulrush (Schoenoplectus pungens) every two weeks throughout the summer season (June-September 2022) in terms of stem density, percent cover, and percent of stems grazed. Results indicated that there was no difference in stem density, percent cover, and percent of stems grazed between the two fencing types. However, compared to bulrush in the controls, both snow and metal fencing treatments yielded a higher stem density and percent cover (x̄% difference = 82.9%, 53.1%, respectively) as well as a lower percent of stems grazed. These results suggest that both fencing materials are equally effective at deterring goose herbivory in a tidal marsh. Additional assessments are needed to clarify whether this technique can be scaled up to promote marsh recovery throughout the entire area of recession., tidal marsh recession, goose herbivory deterrents, goose management, Canada geese, common three-square bulrush, snow fencing, chain-link fencing
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
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)
Restoration of the Little Qualicum River Estuary has focused on re-establishing the Carex lyngbyei channel edge vegetation lost to grubbing by the overabundant resident Canada goose population. Short-term sediment deposition rates were measured using weekly deployments of sediment traps between June and July 2019 to investigate how restoration is facilitating sediment retention to rebuild the marsh platform.
Deposition rates varied between 6.82-107.88 g/m2/week with traps deployed on the denuded mud flat areas collecting more sediments than inside the older exclosures. It had been expected that the exclosures with a greater density of sedges would retain more sediment. Spatial variation may be attributed to differences in sampling elevations. Restoring C. lyngbyei may not increase localized sediment deposition directly but does protect the continued supply of organic input from the seasonal senescence of C. lyngbyei. The organic input from aboveground biomass may have a larger contribution to marsh accretion than allochthonous sediments., sediment deposition, Carex lyngbyei, estuary, restoration, Canada goose
Options for ecological restoration are discussed for the Clear Lake – South Lake complex of Riding Mountain National Park, Manitoba. This project consisted of a) a review of studies conducted on Clear Lake and South Lake and b) a stream water quality sampling program. The review of previous studies was to gain an in-depth understanding of historical processes which shaped Clear Lake and South Lake. Previous condition, current condition and ecological stressors are all identified based on literature from Riding Mountain National Park. The stream water quality sampling program identifies major sources of nutrients into Clear Lake. Ecological restoration options pertain specifically to the Clear Lake – South Lake complex. South Lake restoration options include supplemental planting, dredging and chemical treatments. A novel technique designed to disrupt wind driven nutrient loading is also discussed. These methods are designed to return the South Basin to a macrophyte dominated system. Addressing hypolimnetic oxygen deficiency, two forms of hypolimnetic aeration are discussed to improve water quality in Clear Lake including a ‘Full lift’ design as well as a Speece Cone. Three options regarding the isthmus and connectivity between Clear Lake and South Lake are examined including a fishway installation and a wattle fence installation.