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Pacific sand lance (Ammodytes personatus) support marine food webs in the Salish Sea, yet our knowledge of intertidal spawning habitat for this species is limited. Increasing participation in community science surveys for intertidal sand lance spawning has resulted in the detection of eggs on more than 90 beaches in the Canadian Salish Sea since 2001. Using these data, we developed a MaxEnt habitat suitability model using six environmental variables. We estimate that only 5.4% of the intertidal zone of the Canadian Salish Sea has a moderate to high likelihood of providing suitable sand lance spawning habitat. This rare habitat was best predicted by its proximity to estuaries, shoreline slope, distance to predicted subtidal sand lance burying habitat, seabed substrate, and aspect. Our model could be used as the basis for a Pacific coast-wide model in areas with less available information. Identifying intertidal spawning habitat of sand lance will support conservation efforts intended to maintain forage fish species. Si le lancon du Pacifique (Ammodytes personatus) supporte des reseaux trophiques marins dans la mer des Salish, les connaissances sur l'habitat intertidal de frai de cette espece sont limitees. La participation croissante par des citoyens scientifiques au recensement des aires de frai intertidales des lancons s'est traduite par la detection d'oeufs sur plus de 90 plages dans la mer des Salish canadienne depuis 2001. A partir de ces donnees, nous avons mis au point un modele MaxEnt de qualite de l'habitat qui integre six variables environnementales. Nous estimons que seuls 5,4 % de la zone intertidale de la mer des Salish canadienne presente une probabilite moderee a elevee de fournir des habitats de frai convenables pour les lancons. Les meilleurs predicteurs de ces habitats rares sont la proximite d'estuaires, la pente du rivage, la distance par rapport a des habitats de fouissage subtidaux des lancons et le substrat et l'aspect du fond marin. Notre modele peut servir de base pour un modele a l'echelle du littoral du Pacifique pour des secteurs pour lesquels peu d'information est disponible. La delimitation d'habitats de frai intertidaux de lancons appuiera les efforts de conservation visant le maintien d'especes de poissons-fourrage. [Traduit par la Redaction], Introduction Pacific sand lance (Ammodytes personatus) are small ( Despite their key role in supporting marine food webs, knowledge of intertidal sand lance habitat requirements within the Salish Sea is [...]

Estuaries represent a transition zone for salmon migrating from fresh water to marine waters, yet their contribution to juvenile growth is poorly quantified. Here, we use genetic stock identification and otolith analyses to quantify estuarine habitat use by Chinook salmon (Oncorhynchus tshawytscha)--the Pacific salmon species considered most reliant on this habitat--in Canada's most productive salmon river, the Fraser River. Two years of sampling revealed subyearling migrant (ocean-type) Chinook from the Harrison River to be the estuary's dominant salmon population throughout the emigration period. These Chinook salmon were caught predominantly in the estuary's brackish marshes but shifted to more saline habitats as they grew. Otolith analyses indicated that these Chinook salmon have wide-ranging entry timing (from February to May) and longer estuarine residency (weeks to months, mean 41.8 days) than estimated by prior studies, but similar daily growth rates (mean [+ or -] SD: 0.57 [+ or -] 0.13 mm) across entry dates and residency periods, implying sufficient foraging opportunities throughout the emigration period and habitats. Together, these results suggest that estuarine habitat is more important for early marine growth of subyearling migrant Chinook salmon than previously recognized. Si les estuaires constituent des zones de transition pour les saumons migrants de l'eau douce vers la mer, leur contribution a la croissance des juveniles n'est pas bien quantifiee. Nous utilisons l'identification genetique au stock et des analyses d'otolites pour quantifier l'utilisation de l'habitat estuarien par le saumon chinook (Oncorhynchus tshawytscha) -l'espece de saumon du Pacifique consideree comme dependant le plus de cet habitat--dans la riviere a saumons la plus productive du Canada, le fleuve Fraser. Deux annees d'echantillonnage revelent que des saumons chinooks migrants (type oceanique) de moins d'un an issus de la riviere Harrison constituaient la population dominante de saumons dans l'estuaire durant toute la periode d'emigration. Ces saumons chinooks ont ete captures principalement dans les marais saumatres de l'estuaire, mais se deplacaient vers des habitats plus salins au fil de leur croissance. Les analyses d'otolites indiquent que ces saumons chinooks presentent une grande fourchette de dates d'entree en mer (de fevrier en mai) et de plus longues durees de residence dans l'estuaire (de plusieurs semaines a plusieurs mois, pour une moyenne 41,8 jours) que ce qu'estimaient des etudes anterieures, mais des taux de croissance quotidiens semblables (moyenne [+ or -] ET: 0,57 [+ or -] 0,13 mm) peu importe la date d'entree ou la duree de residence, ce qui indiquerait des occasions d'approvisionnement suffisantes durant toute la periode et dans tous les habitats d'emigration. Collectivement, ces resultats donnent a penser que l'habitat estuarien est plus important pour le debut de la croissance en mer de saumons chinooks migrants de moins d'un an que ce qui etait reconnu auparavant. [Traduit par la Redaction], Introduction Chinook salmon display high plasticity in their life history strategies, including the extent of rearing time in fresh water before downstream migration (Bourret et al. 2016; COSEWIC 2018). Subyearling [...]

Sumas Lake (Xhotsa), located in the Fraser Valley, British Columbia, Canada, was the heart of Sema:th́ Nation Territory and the epicenter of a complex Indigenous food system. For the Sema:th́ 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 ($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 Sema:th́ 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. [ABSTRACT FROM AUTHOR]

Voting systems aggregate preferences efficiently and are often used for deciding conservation priorities. Desirable characteristics of voting systems include transitivity, completeness, and Pareto optimality, among others. Voting systems that are common and potentially useful for environmental decision making include simple majority, approval, and preferential voting. Unfortunately, no voting system can guarantee an outcome, while also satisfying a range of very reasonable performance criteria. Furthermore, voting methods may be manipulated by decision makers and strategic voters if they have knowledge of the voting patterns and alliances of others in the voting populations. The difficult properties of voting systems arise in routine decision making when there are multiple criteria and management alternatives. Because each method has flaws, we do not endorse one method. Instead, we urge organizers to be transparent about the properties of proposed voting systems and to offer participants the opportunity to approve the voting system as part of the ground rules for operation of a group.

Species distribution models (SDMs) are increasingly proposed to support conservation decision making. However, evidence of SDMs supporting solutions for on-ground conservation problems is still scarce in the scientific literature. Here, we show that successful examples exist but are still largely hidden in the grey literature, and thus less accessible for analysis and learning. Furthermore, the decision framework within which SDMs are used is rarely made explicit. Using case studies from biological invasions, identification of critical habitats, reserve selection and translocation of endangered species, we propose that SDMs may be tailored to suit a range of decision-making contexts when used within a structured and transparent decision-making process. To construct appropriate SDMs to more effectively guide conservation actions, modellers need to better understand the decision process, and decision makers need to provide feedback to modellers regarding the actual use of SDMs to support conservation decisions. This could be facilitated by individuals or institutions playing the role of 'translators' between modellers and decision makers. We encourage species distribution modellers to get involved in real decision-making processes that will benefit from their technical input; this strategy has the potential to better bridge theory and practice, and contribute to improve both scientific knowledge and conservation outcomes.

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. [ABSTRACT FROM AUTHOR]