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Effective conservation requires that species recovery measures are informed by rigorous scientific research. For imperilled freshwater fishes and mussels in Canada, numerous research gaps exist, in part owing to the need for specialized research methods. The Canadian Freshwater Species at Risk Research Network (SARNET) was formed and identified or implemented approaches to address current research gaps, including (1) captive experimental research populations, (2) nonlethal methods for estimating abundance and distribution, (3) nonlethal field methods to measure life-history parameters, (4) species distribution models informed by co-occurring species, (5) conservation physiology to inform habitat and threat science, (6) evidence syntheses to evaluate threats and recovery measures, (7) disease-transmission models to understand mussel-host relationships, (8) experimental mesocosms and manipulative experiments to evaluate key habitat stressors, (9) threat and hazard models for predictive applications, and (10) rigorous evaluation of surrogate species. Over a dozen threat- and recovery-focused SARNET research applications are summarized, demonstrating the value of a coordinated research program between academics and government to advance scientific research on, and to support the recovery of, imperilled freshwater species. Des mesures de retablissement reposant sur des travaux de recherche scientifique rigoureux sont necessaires a une conservation efficace. Pour les especes de poissons d'eau douce et mulettes en peril au Canada, il existe de nombreuses lacunes dans la recherche, dues partiellement a la necessite de methodes de recherche specialisees. Le reseau canadien de recherche sur les especes d'eau douce en peril (SARNET) a ete cree et il a cerne ou applique differentes approches visant a combler ces lacunes, dont les suivantes : (1) des populations experimentales captives de recherche, (2) des methodes non letales d'estimation de l'abondance et de la repartition, (3) des methodes de terrain non letales de mesure de parametres du cycle biologique, (4) des modeles de repartition des especes integrant des donnees sur les especes cooccurrentes, (5) la physiologie de la conservation pour soutenir les travaux scientifiques sur les habitats et les menaces, (6) des syntheses de donnees probantes pour evaluer les menaces et measures de retablissement, (7) des modeles de transmission des maladies pour comprendre les relations mulettes-hotes, (8) des mesocosmes experimentaux et des experiences de manipulation pour evaluer des facteurs de stress cles des habitats, (9) des modeles de menaces et de dangers pour des applications predictives et (10) Revaluation rigoureuse d'especes substitutives. Un resume de plus d'une douzaine d'applications des travaux de recherche du SARNET axees sur les menaces et le retablissement est presente, qui demontre l'utilite d'un programme de recherche au sein duquel les travaux de chercheurs universitaires et gouvernementaux sont coordonnes afin de faire avancer la recherche scientifique sur les especes d'eau douce en peril et soutenir leur retablissement. [Traduit par la Redaction], Introduction An important goal of conservation biology is to prevent species extinctions caused by human activity (Soule 1985). When populations decline and become imperilled, various recovery measures are often enacted [...]

We compared the genetic diversity and structure of wild versus captive-propagated at-risk species of freshwater mussels in Canada, Lampsilis fasciola (wavy-rayed lampmussel; WRL) and Ptychobranchus fasciolaris (kidneyshell; KS), using microsatellite-generated genotypes. No significant differences were detected using Kruskal-Wallis tests that compared the genetic diversity metrics of wild and captive-propagated WRL (from 12 mothers) and KS (from seven mothers). After effective population size ([N.sub.e]) was estimated, considerable overlap was found in the estimated [N.sub.e] between wild and captive populations of both species. Pairwise [F.sub.ST] and [D.sub.est] values among wild WRL, hatchery-raised WRL juveniles, and across different time periods (2008-2018) were generally low ([F.sub.ST] = 0.007-0.043, [D.sub.est] = 0.005-0.282). Pairwise [F.sub.ST] and [D.sub.est] for KS were not significant and low (0.012, 0.017). When comparing captive-reared offspring with the wild population, STRUCTURE analysis revealed strong support for a single genetic population. With at least seven females contributing to brood stock, genetic diversity was maintained. Further research is needed to assess the male contribution to each glochidial brood as well as the variability of genetic diversity in individual glochidial broods. Nous avons compare la diversite et la structure genetiques de deux mulettes en peril au Canada, la lampsile fasciolee (Lampsilis fasciola, LF) et le ptychobranche reniforme (Ptychobranchusfasciolaris, PF), sauvages et issues de la propagation en captivite, en utilisant des genotypes generes a partir de microsatellites. Aucune difference significative n'est relevee entre les populations sauvages et propagees en captivite de LF (issues de 12 meres) ou de PF (issues de sept meres) a la lumiere de differents parametres de diversite genetique en utilisant des tests de Kruskal-Wallis. La taille effective de la population ([N.sub.e]) a ete estimee, et un chevauchement considerable est releve entre les [N.sub.e] estimees des populations sauvages et propagees en captivite des deux especes. Les valeurs de [F.sub.ST] et [D.sub.est] par paire de LF sauvages, de LF juveniles elevees en ecloseries et pour differentes periodes (de 2008 a 2018) sont generalement faibles ([F.sub.ST] = 0,007-0,043, [D.sub.est] = 0,005-0,282). Les valeurs de [F.sub.ST] et [D.sub.est] par paire de PF sont faibles (0,012, 0,017) et non significatives. Pour la comparaison de progeniture elevee en captivite a la population sauvage, les resultats de l'analyse avec le logiciel STRUCTURE appuient fortement l'interpretation d'une seule population genetique. Si au moins sept femelles contribuent au stock de geniteurs, la diversite genetique est maintenue. D'autres travaux de recherche sont necessaires pour evaluer la contribution des males a chaque emission de glochidies et la variabilite de la diversite genetique au sein de ces emissions. [Traduit par la Redaction], Introduction Freshwater mussels (Bivalvia: Unionida, unionids) are one of the most imperilled taxa on the planet, with 70% of unionid species in North America at risk of extinction (Williams et [...]

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Among the highest profile invasive species in the Laurentian Great Lakes region are Dreissena polymorpha and D. rostriformis bugensis (collectively dreissenids). Despite their abundance and ecosystem-wide effects, little is known about dreissenid distributions in large connecting channels between lakes. The objectives of this study were to estimate and document dreissenid densities and their habitat characteristics throughout the St. Clair River, to compare dreissenid species demographics, and predict spatial distributions between two connecting waters of the Great Lakes: the St. Clair and Detroit rivers. Two types of species distribution models (SDMs), MaxEnt and classification and regression tree analysis (CART), were created using dreissenid and habitat data collected in both the Detroit and St. Clair rivers. The SDMs were then used to predict presence of dreissenids in the St. Clair River. The St. Clair River had more D. r. bugensis (mean density = 486 ± 152 individuals/m2) than D. polymorpha (mean density = 3 ± 1 individuals/m2). The SDMs created from the Detroit River data reliably predicted presence of dreissenids in the St. Clair River. Depending on the river and species, CART models identified velocity and depth to be important predictor variables, while distance to river inlet/outlet were the most influential variables in the MaxEnt models. Most research on dreissenid distribution modeling is focused on determining areas for potential spread; however, this study presents a unique perspective by modeling dreissenid presence, both D. polymorpha and D. r. bugensis separately and together, where they have been established for more than 30 years. [ABSTRACT FROM AUTHOR]