Browsing by Author "Frid, Alejandro"
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Item Comparison of environmental DNA and SCUBA diving methods to survey keystone rockfish species on the Central Coast of British Columbia, Canada(Ecological Indicators, 2024) Acharya-Patel, Neha; Groenwold, Emma; Lemay, Matthew A.; Clemente-Carvalho, Rute; Morien, Evan; Dudas, Sarah; Rubidge, Emily; Yang, Cecilia Lingyu; Coombe, Lauren; Warren, René L.; Frid, Alejandro; Birol, Inanc; Helbing, Caren C.The rocky reefs of British Columbia’s (BC) coast are a productive ecosystem, home to 38 rockfish species (Genus: Sebastes) that are culturally and economically important. Quantitatively assessing rockfish populations is vital to support conservation and stock assessment needs. Self-contained underwater breathing apparatus (SCUBA) diving surveys are a commonly used monitoring method in BC. However, this resource-intensive approach is challenging, particularly for cryptic or deeper species. Herein, we compared environmental DNA (eDNA) detection methods with SCUBA diving surveys to capture overall rockfish biodiversity. We employed two eDNA methods: 1) a targeted quantitative real-time polymerase chain reaction (qPCR) approach to monitor species of particular importance to First Nations collaborators and decision makers, and 2) a metabarcoding approach for assessing community composition using the previously published MiSebastes assay. Both approaches are confounded by the little DNA sequence divergence among species and high sequence variation within species. Overcoming these challenges using a whole mitochondrial approach with the mtGrasp and unikseq pipelines, we generated highly useful eDNA tools. We found that eDNA methods were highly comparable to dive surveys, as both methods indicated a similar ecological reality, including species detections and distributions. Though there are certain species that cannot be distinguished by the MiSebastes assay, eDNA metabarcoding still detected more rockfish species overall. Both eDNA methods show potential for use alongside conventional methods for scalable incorporation into community-based monitoring programs.Item Conservation Risk and Uncertainty in Recovery Prospects for a Collapsed and Culturally Important Salmon Population in a Mixed-Stock Fishery(Marine and Coastal Fisheries, 2019) Connors, Brendan; Atlas, William; Melymick, Christina; Moody, Megan; Moody, Jason; Frid, AlejandroMixed‐stock fisheries simultaneously exploit populations that may differ in their conservation status, and uncertainty in stock‐specific harvest rates can hamper evaluations of recovery prospects for depressed populations. These difficulties are exemplified in the Sockeye Salmon population from the Atnarko watershed, which collapsed in the early 2000s, causing cultural and economic hardship. A recovery plan identified the incidental harvest of Sockeye Salmon by mixed‐stock fisheries in the Atnarko as a potential, but poorly understood, impediment to recovery. We reconstructed harvest rates for salmon in Indigenous and commercial fisheries and used an age‐structured state‐space model of stock–recruit dynamics to predict how a range of future mixed‐stock harvest rates would influence recovery. Under recent harvest rates, there is a 50–60% chance that the population will grow to exceed a recovery goal of 15,000 spawners over the next four generations. Eliminating the harvest of Sockeye Salmon altogether increased predicted recovery prospects to a maximum of 69%, suggesting that factors other than fisheries are contributing to the lack of recovery (e.g., ocean conditions) and that harvest management alone is unlikely to lead to recovery with a high degree of certainty. We developed a generalized migration, harvest, and catch monitoring simulation model to quantify how different monitoring scenarios might improve estimates for mixed‐stock harvest rates. Increasing the number of specimens collected for genetic samples improved the harvest rate estimates for each stock caught in the mixed‐stock fisheries, particularly for the smallest stocks, and relative to single sampling events conducted near the peak of the return migration, weekly sampling improved estimates only slightly but provided insurance against missing the peak of the return migration. Our study highlights collaborative research initiated and directed by the Nuxalk Nation to promote the recovery of a depressed stock that is inherent to traditional foods, thereby contributing to a global effort to integrate Indigenous cultural values with biological conservation.Item Inclusivity of Indigenous Knowledge Systems in fisheries management(Fish and Fisheries, 2025) Moffat, Keshia; Snook, Jamie; Paul, Kenneth; Frid, AlejandroIndigenous Peoples have developed knowledge systems that foster respectful and reciprocal relations between humans and other-than-human beings, supporting resilient ecosystems and societies. Despite the impacts of colonisation, Indigenous Knowledge Systems (IKS) endure in many parts of the world, and there is growing recognition that IKS can strongly improve fisheries management. During the last 5 years, Fisheries and Oceans Canada (DFO), the federal institution responsible for managing Canada's fisheries, released policies and strategies intended to make fisheries management more inclusive of IKS. To measure progress in their implementation, we applied 13 semiquantitative indicators and qualitative analyses of IKS inclusivity to a sample of 78 public documents produced or co-produced by DFO to advise management decisions. Of these documents, ≈87% reported cases that did not meaningfully include Indigenous Peoples and their IKS, 9.0% reported cases in which Indigenous Peoples were included in some aspects of research but their IKS was not, ≈3% reported cases in which IKS contributed to objectives and elements of research design but the process privileged Western science over IKS, and only one document met a high standard for the pairing of IKS and Western science. The indicators that we developed in a Canadian context can be used, with locally appropriate revisions, to gauge the extent to which state governments in other countries are inclusive of IKS in fisheries management, thereby identifying shortcomings in law, policy, and practice and informing mitigation measures. Strengthening the inclusivity of IKS would enable more holistic approaches to fisheries management and benefit global conservation.Item Prioritizing conservation actions for Pacific salmon in Canada(Journal of Applied Ecology, 2020) Walsh, Jessica C.; Connors, Katrina; Hertz, Eric; Kehoe, Laura; Martin, Tara G.; Connors, Brendan; Bradford, Michael J.; Freshwater, Cameron; Frid, Alejandro; Halverson, Jessica; Moore, Jonathan W.; Price, Michael H. H.; Reynolds, John D.Current investment in conservation is insufficient to adequately protect and recover all ecosystems and species. The challenge of allocating limited funds is acute for Pacific salmon Oncorhynchus spp. in Canada, which lack a strategic approach to ensure that resources are spent on actions most likely to cost‐effectively recover diminished populations. We applied the Priority Threat Management framework to prioritize strategies most likely to maximize the number of thriving Pacific salmon populations on the Central Coast of British Columbia, Canada. These included 79 genetically, ecologically and spatially distinct population groups called conservation units (CUs) for five salmon species. This region has high salmon biodiversity and spans the territories of four First Nations: the Heiltsuk, Nuxalk, Kitasoo/Xai'xais and Wuikinuxv. Using structured expert elicitation of Indigenous and other experts, we quantified the estimated benefits, costs and feasibility of implementing 10 strategies. Under a business‐as‐usual scenario (i.e. no additional investments in salmon conservation or management), experts predicted that only one in four CUs would have >50% chance of achieving a thriving status within 20 years. Limiting future industrial development in salmon habitats, which was predicted to safeguard CUs from future declines, was identified as the most cost‐effective strategy. Investment in three strategies: (a) removal of artificial barriers to fish migration, (b) watershed protection and (c) stream restoration—at 11.3M CAD per year—was predicted to result in nearly half (34 of 79) of the CUs having a >60% chance of meeting the conservation objective. If all conservation strategies were implemented, experts estimated a >50% probability of achieving a thriving status for 78 of 79 CUs, at an annual cost of 17.3M CAD. However, even with the implementation of all strategies, most sockeye salmon CUs were unlikely to achieve higher probability targets of reaching the objective. Policy implications . We illustrate how Priority Threat Management can incorporate the perspectives and expertise of Indigenous peoples and other experts to prioritize conservation strategies based on their cost, benefit and feasibility. Implementation of this framework can help safeguard and recover Pacific salmon in Canada, and could also be used to prioritize actions for other conservation issues globally.Item Rockfish size and age: The crossroads of spatial protection, central place fisheries and indigenous rights(Global Ecology and Conservation, 2016) Frid, Alejandro; McGreer, Madeleine; Haggarty, Dana R.; Beaumont, Julie; Gregr, Edward J.Indigenous people harvest wild species for food and cultural practice, fundamentally linking biodiversity conservation and indigenous rights. Rockfishes (Sebastes spp.) are culturally significant to indigenous people (or First Nations) of coastal British Columbia (BC), Canada, who regulate their harvest under traditional governance structures. First Nations elders, however, have observed a decline in the body sizes and abundance of rockfishes, which coincides with increased exploitation by non-indigenous fishers. Rockfishes are vulnerable to overexploitation because fecundity and offspring quality increase with maternal size or age, yet fisheries truncate size and age structure. During 2006, 2007 and 2013–2015, we worked with the Wuikinuxv, Nuxalk, Heiltsuk and Kitasoo/Xai’Xais First Nations of BC’s Central Coast, examining rockfish population characteristics at 282 of their fishing sites. We used hook-and-line gear to collect fishery independent data, and sampled landings from First Nations subsistence fishers. Spatial fishery closures served as experimental treatments. We also applied central place foraging theory to predict declines in size, age and abundance with increasing distance from recreational fishing lodges and other ports. Analyses used linear mixed models and controlled for environmental variables. Our results suggest that spatial closures for commercial and recreational fishers led to greater size and abundance of some, but not all rockfishes, possibly due to interspecific differences in the extent to which closures contain suitable habitat, effects of non-compliance, or other factors. Notably, Yelloweye Rockfish (Sebastes ruberrimus), a species key to indigenous diets, were 21% larger inside than outside spatial closures. Possibly reflecting cumulative fishery exploitation, however, old-aged Yelloweye Rockfish were rare. Fishery impacts on size and relative abundance decreased at sites that required longer travel times and greater fuel costs for recreational fishers to exploit, but only for the longest-lived species (size responses) and for long-lived species analysed in aggregate (abundance responses). Measures for protecting indigenous access to rockfishes include evaluation of habitat suitability and compliance within spatial closures, improved understanding of recreational fishery impacts, and treating old-age and large size structures as explicit management objectives. Our study contributes to a global effort to integrate indigenous cultural values with biological conservation.