Riley J. R. Finn’s research while affiliated with University of British Columbia and other places

What is this page?


This page lists works of an author who doesn't have a ResearchGate profile or hasn't added the works to their profile yet. It is automatically generated from public (personal) data to further our legitimate goal of comprehensive and accurate scientific recordkeeping. If you are this author and want this page removed, please let us know.

Publications (7)


FIGURE 1
FIGURE 2
FIGURE 3
FIGURE 4
FIGURE 6

+1

Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake
  • Article
  • Full-text available

June 2024

·

56 Reads

·

2 Citations

Frontiers in Conservation Science

Riley J. R. Finn

·

Murray Ned - Kwilosintun

·

Leah Ballantyne

·

[...]

·

Sumas Lake ( Xhotsa ), located in the Fraser Valley, British Columbia, Canada, was the heart of Semá:th Nation Territory and the epicenter of a complex Indigenous food system. For the Semá:th people, the lake represented life and livelihood. In 1924, the lake was stolen and drained in an instance of land theft that occurred during a nationwide campaign of land dispossession and genocide, decimating an ecology that supported a rich and diverse Indigenous food system and replacing it with a settler food system. A century later, in November 2021 climate change induced flooding caused the lake to return, resulting in the evacuation of thousands of people and causing millions in damages to homes and infrastructure. Since the flood, the response has been a continuation of the status quo to protect settler agricultural lands via increased investment in hard structures that control the flow of water based on assumptions of the predictability of future flow conditions. We offer a missing narrative by bringing together an analysis of Indigenous laws and oral tradition with an assessment of the economic costs of “managed retreat”, defined as the purposeful relocation of people and infrastructure out of harm’s way. We find that the cost of buying out properties in the lakebed and allowing the lake to return is close to half the cost (1billion)ofmaintainingthestatusquo(1 billion) of maintaining the status quo (2.4 billion), while facilitating climate adaptation, and restoration of a floodplain ecosystem that supported thriving populations of people, salmon, sturgeon, ducks, and food and medicinal plants– including many species which are now endangered. Returning Sumas Lake by centering ‘Water Back’ as a climate resiliency solution, enacts both food systems and ecological reconciliation, addressing the harms caused by the loss of the lake to the Semá:th People that is still felt to this day. In a time when climate change induced flooding is predicted to increase, this study demonstrates how the inclusion of Indigenous laws and knowledges are critical to the development of solutions toward a more sustainable and just future.

Download

Predicting regional cumulative effects of future development on coastal ecosystems to support Indigenous governance

May 2024

·

79 Reads

·

4 Citations

To achieve better biodiversity outcomes and match local governance capacity, cumulative effects assessment frameworks that combine Indigenous and western knowledge to predict future development impacts on biodiversity are needed. We developed a spatial future‐focused model informed by inclusive elicitation and strategic foresight to assess the regional cumulative effects of development on ecosystem health across the land and sea. We collaborated with three First Nations on the Central Coast of British Columbia, Canada, enabling Indigenous priorities, knowledge and values to drive the process, from the choice of priority ecosystem components (including salmon, herring, seabirds and bears), to identifying future development scenarios (based on forestry, energy/mining, tourism and salmon aquaculture sectors). Bayesian networks were populated with empirical data and expert judgement elicited from knowledge holders to predict the cumulative effects of current and future pressures on species and ecosystems. Under current conditions, the lowest probability of persistence was predicted for Pacific salmon (37%), followed by Pacific herring (43%). Under future conditions, the greatest declines in species health were associated with the intense development of mining, tourism and forestry, with up to a 54% decline from the current baseline health estimates predicted for Marbled Murrelets and old‐growth forest. Future outcomes for overall ecosystem health were predicted to be worst in scenarios with high future forestry activities (>60% decline in some areas). The continuation or development of all four industries resulted in an 8% decline overall in ecosystem health across the Central Coast. In contrast, predicted ecosystem health in the tourism economy scenario increased up to 15% in some marine areas, primarily driven by the removal of salmon aquaculture and forestry activities. Synthesis and applications. Our study demonstrates an inclusive, regional approach to assessing the cumulative effects of future development on coastal species. The novel participatory tools and predictive framework draw upon and interweave multiple forms of knowledge, enabling Indigenous values to drive the process, and appropriately integrate Indigenous knowledge into regional cumulative effects assessment. Our interactive web application provides First Nations partners access to all outputs, supporting Indigenous‐led governance and in situ ecosystem‐based management of their lands and water.


Using systematic conservation planning to inform restoration of freshwater habitat and connectivity for salmon

June 2023

·

166 Reads

Abstract Instream barriers remain ubiquitous threats to freshwater species and their habitats. Decisions regarding barrier removal are often aimed at maximizing habitat area and connectivity for freshwater fish; yet can be challenging due to the sheer number of barriers, uncertainty in species presence, abundance, and habitat quality, as well as limited budgets alongside high costs of restoration. Here, we apply systematic conservation planning to prioritize in‐stream barrier removal aimed at restoring habitat connectivity for 14 populations of wild Pacific salmon in the lower Fraser River, Canada's most productive salmon‐bearing river. To understand how priorities change when stream quality is considered, we contrast scenarios that maximize habitat extent with scenarios that include four indicators of habitat quality. Region‐wide, approximately 64% of naturally accessible stream length is currently blocked by barriers. We estimate approximately 75% of this alienated habitat (over 1600 km of stream), could have full access restored with an investment of $200 million CAD, whereas 60% could be restored for half this amount. When stream quality was considered within the optimization, priorities for barriers removal shifted away from urbanized floodplain valleys towards less developed areas. The spatial shift in priorities meant that species like chum salmon (Oncorhynchus keta) would see less restored habitat. To inform barrier removal strategies using these model scenarios, an iterative and adaptive approach will be required that includes the values and priorities of rights and titleholders. Continuous improvement in data quality, accuracy, and feedback from monitoring as barriers are restored is also crucial.


Schematic of threats and management tools for Pacific salmon in the lower Fraser River region by habitat. The inner circle (blue) represents available strategies within the realm of freshwater habitat. The next circle (green) represents strategies within the estuary realm, followed by strategies within the nearshore marine realm (grey). Icons represent 11 management strategies identified in this project (Table 1) and are repeated where they apply across realms. Several strategies which influence marine survival were not included in this study due to their international scope, including global reduction of greenhouse gas emissions to reduce the impacts of climate change, international treaty negotiations to minimize hatchery–wild interactions, and large‐scale habitat restoration spanning the North American Pacific coastline.
Overview of the key inputs for Priority Threat Management adapted from Carwardine et al. (2019). For a given objective and project scope (i.e. maximize the number of lower Fraser River salmon CUs that will achieve green status at the end of 25 years), threats are identified and the performance measure for each CU under baseline is assessed. Costs, benefits and feasibility are estimated for each strategy based on the component actions. In this study, a second feasibility estimate was elicited for a co‐governance scenario. The costs, benefits and feasibility for each strategy are used to calculate the cost‐effectiveness and complete the complementarity analysis, which provides the optimal management strategies to inform strategic investments for species recovery. Implementation should ideally follow an adaptive management process that monitors effectiveness according to the project objective. Illustrations of salmon species provided by the Pacific Salmon Foundation.
Map of the lower Fraser study region, including the Lillooet, Harrison River, Lower Fraser and Chilliwack River watershed groups in British Columbia, Canada. Inset map shows the boundary of the Fraser River basin, with the study area highlighted in dark grey. Data for watershed groupings obtained from the Freshwater Atlas (https://www2.gov.bc.ca/gov/content/data/geographic‐data‐services/topographic‐data/freshwater).
The number of lower Fraser River salmon Conservation Units (CUs) that were predicted to achieve >50% (solid dark green line) or >60% (dashed dark blue line) chance of green status by implementing the optimal set of strategies for a given budget. Top: all optimal strategies. Bottom: optimal strategies between 0 and 20 million CAD magnified for clarity. ALL indicates all management strategies combined. Note that no CUs achieved a greater than 70% chance of being assessed as green status at the end of 25 years.
Estimated chance of achieving green status for each of 19 Conservation Units under increasing levels of investment over 25 years. The conservation thresholds of 50% (red) and 60% (black) are highlighted with dashed lines. Business as usual (turquoise, light) represents probabilities under no additional management; with all Strategies (green, dark): all management strategies implemented; with co‐governance (magenta, medium): implementation of Indigenous‐led co‐governance (detailed in SI) in addition to all management strategies.
Identifying a pathway towards recovery for depleted wild Pacific salmon populations in a large watershed under multiple stressors

July 2022

·

286 Reads

·

10 Citations

Pacific salmon (Oncorhynchus spp.) support coastal and freshwater ecosystems, economies and cultures, but many populations have declined. We used priority threat management (PTM), a decision‐support framework for prioritizing conservation investments, to identify management strategies that could support thriving populations of wild salmon over 25 years. We evaluated the potential benefits of 14 strategies spanning fisheries, habitat, pollution, pathogens, hatcheries and predation management dimensions on 19 conservation units (CUs)—genetically and ecologically distinct populations—of the five Pacific salmon species in the lower Fraser River, British Columbia, Canada. The PTM assessment indicated that under the current trajectory of ‘business as usual’, zero CUs were predicted to have >50% chance of thriving in 25 years. Implementation of all management strategies at an annual investment between 45 and 110 million CAD was, however, predicted to achieve >50% chance of thriving for most CUs (n = 16), with nearly half (seven CUs) having a > 60% chance, indicating there is a pathway towards recovery for most populations if we invest now. In fact, substantial gains could be made by investing in five combined habitat strategies, costing 20M CAD annually. These habitat strategies were estimated to bring 14 of 19 salmon CUs above this 50% threshold. Co‐governance between First Nation and provincial and federal Canadian governments to manage salmon populations and harvest, and improved CU‐level monitoring emerged from the expert elicitation as critical ‘enabling’ strategies. By improving the feasibility of different management options, co‐governance brought an additional five CUs above the 60% threshold. Synthesis and applications. Supporting wild salmon in the face of cumulative threats will require strategic investment in effective management strategies, as identified by this priority threat management (PTM) assessment. PTM uses the best available data to objectively assess the potential outcomes of management alternatives. With renewed commitments from provincial and federal Canadian governments to protect and restore salmon populations and their habitats, positive conservation outcomes following implementation of targeted management strategies may be within reach.


A model for how decisions should be made. As suggested by Keeney (2004), out of 10,000 decisions, many (∼9000) can be made intuitively or have small consequences and do not warrant more thought or application of decision science. The remaining 1000 decisions are worthy of more thought (challenges in Table 1). Many decisions (∼750) could be improved by simply thinking through the decision consistent with the steps of decision analysis. The remaining decisions (∼250) may require additional analysis, the level of which will be identified by further rapid prototyping of the decision and application of a few simple tools. Very few, typically the most complex decisions (∼50 [0.5%]), will require a full decision analysis and would benefit from more time and resources
A conceptual overview of decision science and the relationship between key terms. Prescriptive decision theory guides decision analysis (combines insights from normative and descriptive decision theory) (see “Decision theory”). Pr, problem; O, objectives; A, alternatives; C, consequence; T, trade‐offs; D, deciding and implementing; M, monitoring; Pr, O, A, C, and T precede D and M. Decision‐support tools provide insight at each component; decision‐support frameworks help to step through multiple components (see “Decision‐support frameworks and tools”)
Decision analysis (commonly referred to as structured decision‐making) follows the PrOACT steps (steps 1–5) to help inform decisions. Once a decision is made (step 6), monitoring is often used (step 7) to evaluate the outcomes of the decision or to continue to learn about the consequences (link between 7 and 4) or the problem (link between 7 and 1) (dashed arrows, process is often iterative and return to a previous step may be needed as new information is obtained; white boxes, decision‐support tools available for a step). Appendix S1 describes these tools and provides useful references for their application. Figure adapted from Garrard et al. (2017)
An introduction to decision science for conservation

January 2022

·

537 Reads

·

86 Citations

Biodiversity conservation decisions are difficult, especially when they involve differing values, complex multidimensional objectives, scarce resources, urgency, and considerable uncertainty. Decision science embodies a theory about how to make difficult decisions and an extensive array of frameworks and tools that make that theory practical. We sought to improve conceptual clarity and practical application of decision science to help decision makers apply decision science to conservation problems. We addressed barriers to the uptake of decision science, including a lack of training and awareness of decision science; confusion over common terminology and which tools and frameworks to apply; and the mistaken impression that applying decision science must be time consuming, expensive, and complex. To aid in navigating the extensive and disparate decision science literature, we clarify meaning of common terms: decision science, decision theory, decision analysis, structured decision‐making, and decision‐support tools. Applying decision science does not have to be complex or time consuming; rather, it begins with knowing how to think through the components of a decision utilizing decision analysis (i.e., define the problem, elicit objectives, develop alternatives, estimate consequences, and perform trade‐offs). This is best achieved by applying a rapid‐prototyping approach. At each step, decision‐support tools can provide additional insight and clarity, whereas decision‐support frameworks (e.g., priority threat management and systematic conservation planning) can aid navigation of multiple steps of a decision analysis for particular contexts. We summarize key decision‐support frameworks and tools and describe to which step of a decision analysis, and to which contexts, each is most useful to apply. Our introduction to decision science will aid in contextualizing current approaches and new developments, and help decision makers begin to apply decision science to conservation problems.



Quantifying lost and inaccessible habitat for Pacific salmon in Canada’s Lower Fraser River

July 2021

·

241 Reads

·

19 Citations

Loss of connectivity caused by anthropogenic barriers is a key threat for migratory freshwater species. The anadromous life history of salmonids means that barriers on streams can decrease the amount of habitat available for spawning and rearing. To set appropriate targets for restoration, it is important to know how different populations have been impacted in terms of the location and extent of historically available habitat that has been lost or has become inaccessible. Using mapped and predicted barriers to fish passage in streams and diking infrastructure, the amount of both floodplain and linear stream habitat that remains accessible today was estimated for 14 populations of salmon in the Lower Fraser River, British Columbia, Canada’s most productive salmon river. To place these estimates within a historical context, the floodplain area was estimated using vegetation records from the 1850s, and lost streams were estimated using a digital elevation model‐derived stream network. To bolster areas where little mapping has been done, current barrier data were used to predict locations likely to have barriers. Accessibility to floodplain was poor across the entire region with only 15% of the historical floodplain remaining accessible. Linear stream habitat ranged in accessibility from 28% to 99% across populations based on mapped barriers. Inclusion of predicted barriers revealed an additional 33 km of potentially inaccessible stream habitat and the modeled stream network located approximately 1700 km of stream length that has been completely lost. Comparing habitat accessibility and barrier density against the assessed status of populations revealed insights useful for understanding the impact of barriers on spawning and rearing and guiding the allocation of restoration effort. Applying methods for addressing missing data, such as lost streams and unmapped barriers, was essential for estimating the accessibility of habitat within a historical context. While much emphasis has been placed on the role of marine conditions in wild Pacific salmon recovery, the magnitude of habitat loss in the Fraser cannot be ignored and suggests it is a major driver of observed salmon declines.

Citations (5)


... Exacerbating the region's vulnerability to extreme precipitation, much of FVRD sits on the Sumas Prairie, the historical lakebed of the Sumas Lake (Finn et al. 2024). In the early 1920 s, Sumas Lake was drained to allow for agricultural development (Olsen, 2016;Olsen & Kennedy, 2021). ...

Reference:

"Sometimes, I just want to scream": Institutional barriers limiting adaptive capacity and resilience to extreme events
Reclaiming the Xhotsa: climate adaptation and ecosystem restoration via the return of Sumas Lake

Frontiers in Conservation Science

... While care needs to be taken when applying quantitative models to more social and cultural contexts, modelling options are usefully expanding there also (Gotts et al. 2019). For example, the use of Bayesian belief networks has helped address First Nations and community concerns around fisheries management and ecosystem health, and to assert their governance authority (Reid et al. 2021;Tulloch et al. 2024). Recent research argues for trans-systemic approaches, which Content courtesy of Springer Nature, terms of use apply. ...

Predicting regional cumulative effects of future development on coastal ecosystems to support Indigenous governance

... This multifaceted perspective will enable researchers to identify the critical life stages when salmonids are particularly vulnerable to environmental pressures. Consequently, this understanding will help inform targeted conservation and management strategies to sustain salmonid populations and implement informed measures, mitigating cumulative stressor impacts and preserving the ecological and socioeconomic services provided by these fish species (Chalifour et al. 2022). Understanding stressor responses across all life stages of salmonids is crucial for maintaining a balance between human activities and the preservation of natural heritage. ...

Identifying a pathway towards recovery for depleted wild Pacific salmon populations in a large watershed under multiple stressors

... The rapid accumulation of digital accessible information from citizen science, remote sensing, and data digitization is fundamentally changing the lens through which we view the world (Ball-Damerow et al., 2019;Wüest et al., 2020) and instigating a cascade of developments in ecological modelling to maximise the potential of this knowledge (McCrea et al., 2023). This includes new techniques for integrating datasets (Isaac et al., 2020;Miller et al., 2019;Zipkin & Saunders, 2018), quantifying biodiversity (Latombe et al., 2017;Mammola et al., 2021;Tucker et al., 2017), tracking biodiversity change (Pereira et al., 2013), and supporting conservation decision-making (Hemming et al., 2022). ...

An introduction to decision science for conservation

... Indeed, many such unregulated projects have been implicated as disproportionally large contributors to cumulative effects (Blakley and Russell, 2022). For example, the presence of a non-fish-passable culvert, while a very small physical alteration (i.e., a few square meters), can lead to a profound loss in fish spawning habitat (Finn et al. 2021), which has subsequent cascading impacts on ecosystems (Walsh et al. 2020). The cumulative impacts of these deceptively "small" projects are not captured in a regulated CEA. ...

Quantifying lost and inaccessible habitat for Pacific salmon in Canada’s Lower Fraser River