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Abstract Background Cytosolic calcium overload contributes to muscle degradation in Duchenne muscular dystrophy (DMD). The sarcoplasmic reticulum (SR) is the primary calcium storage organelle in muscle. The sarco-endoplasmic reticulum ATPase (SERCA) pumps cytosolic calcium to the SR during muscle relaxation. Calcium is kept in the SR by calcium-binding proteins. Methods Given the importance of the canine DMD model in translational studies, we examined transcriptional changes of SERCA (SERCA1 and SERCA2a), SERCA regulators (phospholamban, sarcolipin, myoregulin, and dwarf open reading frame), and SR calcium-binding proteins (calreticulin, calsequestrin 1, calsequestrin 2, and sarcalumenin) in skeletal muscle (diaphragm and extensor carpi ulnaris) and heart (left ventricle) in normal and affected male dogs by droplet digital PCR before the onset (≤ 2-m-old), at the active stage (8 to 16-m-old), and at the terminal stage (30 to 50-m-old) of the disease. Since many of these proteins are expressed in a fiber type-specific manner, we also evaluated fiber type composition in skeletal muscle. Results In affected dog skeletal muscle, SERCA and its regulators were down-regulated at the active stage, but calcium-binding proteins (except for calsequestrin 1) were upregulated at the terminal stage. Surprisingly, nominal differences were detected in the heart. We also examined whether there exists sex-biased expression in 8 to 16-m-old dogs. Multiple transcripts were significantly downregulated in the heart and extensor carpi ulnaris muscle of female dogs. In fiber type analysis, we found significantly more type I fiber in the diaphragm of 8 to 16-m-old affected dogs, and significantly more type II fibers in the extensor carpi ulnaris of 30 to 50-m-old affected dogs. However, no difference was detected between male and female dogs. Conclusions Our study adds new knowledge to the understanding of muscle calcium regulation in normal and dystrophic canines.

Reference: Can.J. Fish.Aquat. Sci. 79(8): 1321-1334. https://doi. org/10.1139/cjfas-2021-0112. In Fig. 3 of the originally published article, sites BC1 and CC1 are highlighted in light grey, indicating they were part of [...]

The young-of-year (YOY) habitat of many fishes listed under the Species at Risk Act (SARA) is poorly described, yet identifying critical habitat is essential to ensure species recovery. Past research on the Endangered spotted gar (Lepisosteus oculatus Winchell, 1864) in Canada has focused on the habitat use of adults and juveniles, but little is known about the occurrence and habitat use of YOY. Dip net and aquatic habitat sampling were performed in nearshore (lakefront, agricultural drain), mid-channel (agricultural drain), and offshore sites within Rondeau Bay to determine the fine-scale habitat occupancy patterns of age-0 spotted gar. Habitat preference analysis indicated YOY spotted gar strongly preferred shallow (0.5-1.0 m), vegetated, nearshore (lakefront and agricultural drain) habitat and avoided offshore habitat. An association between submerged aquatic vegetation (SAV) and fish size was also found, as dependence on SAV diminished as total length increased. Our study represents the first capture and assessment of habitat associations of early-stage YOY spotted gar in Canada. Given our findings, management efforts should focus on protecting the vegetated nearshore habitat in Rondeau Bay and other occupied locations in Lake Erie to ensure the long-term persistence of spotted gar in Canada. Key words: spotted gar, Lepisosteus oculatus, critical habitat, submerged aquatic vegetation, habitat selection, coastal wetlands, Endangered, Species at Risk Act, Introduction Understanding the habitat requirements of fish species listed under Canada's Species at Risk Act (SARA) is fundamental for their protection and recovery. However, the habitats required by the early [...]

The reproductive period is a critical part of a species' life history. Estimating species-specific fecundity can improve demographic models aimed at developing recovery targets for imperilled species. We provide egg diameter and fecundity estimates and develop a length-fecundity relationship for silver shiner, Notropis photogenis (Cope, 1865), a small-bodied freshwater species listed as Threatened under Canada's Species at Risk Act. Furthermore, we document the incidence of an acanthocephalan parasite, the thorny-headed worm, Leptorhynchoides thecatus (Linton, 1891), in the gastrointestinal tract of silver shiner, which is the first published record of the parasite in this species. Silver shiner egg diameters (mean [+ or -] standard deviation) were 0.61 [+ or -] 0.15 mm and ranged from 0.13 to 0.92 mm. Fecundity ranged from 311 to 2768 eggs and was significantly higher in age 2-3+ fish (1475 [+ or -] 570 eggs) compared with age 1+ fish (576 [+ or -] 270 eggs). We highlight that parasite infection negatively impacted the body condition of individuals and that additional work is needed to determine the impact of parasite infestation on reproductive output, recruitment, susceptibility to predation, and survival of silver shiner in Canada. The fecundity and egg diameter estimates for Canadian silver shiner provided here can be incorporated into future populations modelling for this threatened species. Key words: spawning, imperilled species, minnows, egg diameter, fecundity length relationship, silver shiner, Notropis photogenis La saison de reproduction est un élément clé du cycle biologique d'une espèce. L'estimation de la fécondité propre à l'espèce peut améliorer les modèles démographiques utilisés pour établir des cibles de rétablissement pour des espèces en péril. Nous présentons des estimations du diamètre des oeufs et de la fécondité et établissons une relation entre la longueur et la fécondité pour le méné-miroir, Notropis photogenis (Cope,1865), une espèce de petit poisson d'eau douce qui figure sur la liste des espèces menacées de la Loi sur les espèces en péril du Canada. Nous documentons en outre l'incidence d'un ver acanthocéphale parasite, Leptorhynchoides thecatus (Linton, 1891), dans le tube gastrointestinal de ménés-miroirs, ce qui constitue la première observation publiée du parasite chez cette espèce. Le diamètre moyen ([+ or -]écart-type) des oeufs de ménés-miroirs est de 0,61 [+ or -] 0,15 mm et la fourchette des valeurs va de 0,13 à 0,92 mm. La fécondité va de 311 à 2768 oeufs et est significativement plus grande chez les poissons de 2-3 ans et plus (1475 [+ or -] 570 oeufs) que chez les poissons d'un an et plus (576 [+ or -] 270 oeufs). Nous soulignons le fait que l'infection par le parasite a un impact négatif sur l'embonpoint des individus et que d'autres travaux sont nécessaires pour déterminer l'impact de l'infestation de parasites sur l'efficacité de la reproduction, le recrutement, la susceptibilité à la prédation et la survie chez le méné-miroir au Canada. Les estimations présentées de la fécondité et du diamètre des oeufs pour des ménés-miroirs canadiens peuvent être intégrées à la modélisation démographique future pour cette espèce menacée. [Traduit par la Rédaction] Mots-clés : frai, espèce en péril, ménés, diamètre des oeufs, relation entre fécondité et longueur, méné-miroir, Notropis photogenis, Introduction Reproduction is a critical component of life history (Winemiller and Rose 1992). Fecundity, in particular, has implications for population dynamics, species persistence, and estimates of minimum viable population size [...]

Freshwater biodiversity is declining from impacts associated with anthropogenic stressors. Here, we use carbon ([[delta].sup.13]C) and nitrogen ([[delta].sup.15]N) stable isotopes to assess food web effects following a coal mine spill that displaced biota and altered biophysical stream characteristics. We compared isotopic niche metrics of benthic macroinvertebrates and the fish community, including non-native brook trout (Salvelinus fontinalis) and endangered Athabasca rainbow trout (Oncorhynchus mykiss), to infer spatial differences in site-specific resource use along a habitat disturbance gradient. Predatory benthic macroinvertebrate trophic position was elevated where impacts from the spill were most pronounced. Autochthonous carbon contribution to consumer diets was lowest in biota sampled at the most highly impacted site from the mine spill, leading to an unexpected expansion of the isotopic niche size of rainbow trout and the aquatic invertebrate community. Collectively, our results suggest variation in trophic resource assimilation across multiple levels of the food web, fueled by the allochthonous energy pathway in highly impacted study sites. We conclude this reflects a biotic response to altered basal aquatic resources following a major industrial disturbance. La biodiversite d'eau douce est en baisse en raison d'impacts associes a des facteurs de stress d'origine humaine. Nous utilisons les isotopes stables du carbone ([[delta].sup.13]C) et de l'azote ([[delta].sup.15]N) pour evaluer les effets sur les reseaux trophiques a la suite d'un deversement issu d'une mine de charbon qui a deplace des organismes et modifie les caracteristiques biophysiques de cours d'eau. Nous comparons des parametres de la niche isotopique de macroinvertebres benthiques et la communaute de poissons, dont l'omble de fontaine (Salvelinus fontinalis), non indigene, et la truite arc-en-ciel (Oncorhynchus mykiss) de l'Athabasca, une espece menacee, afin d'inferer les variations spatiales d'utilisation des ressources dans differents sites le long d'un gradient de perturbation de l'habitat. La position trophique de macroinvertebres benthiques predateurs est rehaussee la ou les impacts du deversement sont les plus prononces. La contribution du carbone autochtone aux regimes alimentaires de consommateurs est la plus faible chez les organismes preleves du site ayant subi les plus grands impacts du deversement minier, menant a une expansion inattendue de la taille de la niche isotopique de la truite arc-en-ciel et de la communaute d'invertebres aquatiques. Collectivement, nos resultats indiqueraient la presence de variations de l'assimilation des ressources trophiques a differents niveaux du reseau trophique, mues par la voie energetique allochtone dans les sites de l'etude ou les impacts sont grands. Nous concluons que cela reflete une reaction biotique a la modification des ressources aquatiques basales dans la foulee d'une importante perturbation d'origine industrielle. [Traduit par la Redaction], 1. Introduction Multiple environmental stressors such as habitat degradation and invasive species can negatively impact freshwater biodiversity (Dudgeon et al. 2006; Fausch et al. 2010), though the interaction among stressors [...]

Understanding the factors underlying species establishment is critical for the management of invasive fishes, yet the roles of propagule pressure and environmental factors are infrequently quantified in joint models. We estimated the establishment likelihood of the invasive black carp (Mylopharyngodon piceus) by examining the relative influence of propagule pressure (introduction size and age structure) and environmental factors (temperature-driven young-of-year [YOY] overwinter survival, adult survival, age at maturity, and longevity). Simulations demonstrated that both propagule pressure and environmental factors can act as non-linear bottlenecks to establishment. When the model was applied to 12 Great Lakes tributaries and nearshore areas, black carp establishment was probable with sufficient propagules and under most environmental conditions (median p = 0.21-0.73, 0.70-1.00, and 0.46-0.97 for 100 pairs of age 4, age 9, and age 16 fish, respectively), except for YOY (p < 0.01). Our analysis is one of the few studies to examine the relative role of propagule pressure and environmental conditions on establishment, indicating that both factors can lead to establishment failure independently or concurrently within an ecosystem. Si la comprehension des facteurs qui sous-tendent l'etablissement d'especes est d'importance cle pour la gestion de poissons envahissants, les roles de la pression de propagule et des facteurs environnementaux ne sont pas souvent quantifies dans les modeles conjoints. Nous estimons la probabilite d'etablissement de la carpe noire (Mylopharyngodon piceus), une espece envahissante, en examinant l'influence relative de la pression de propagule (taille a l'introduction et structure par age) et de facteurs environnementaux (survie hivernale des jeunes de l'annee modulee par la temperature, survie des adultes, age a la maturite et longevite). Des simulations demontrent que tant la pression de propagule que des facteurs environnementaux peuvent agir comme goulots d'etranglement non lineaires pour l'etablissement. Le modele applique a 12 affluents et secteurs littoraux des Grands Lacs montre que l'etablissement de la carpe noire est probable quand il y a assez de propagules et dans la plupart des conditions environnementales (p median = 0,21-0,73, 0,70-1,00 et 0,46-0,97 pour 100 paires de poissons de 4, 9 et 16 ans, respectivement), sauf pour les jeunes de l'annee (p < 0,01). Notre analyse est une des rares etudes a examiner le role relatif de la pression de propagule et des conditions environnementales sur l'etablissement et elle indique que ces deux facteurs peuvent mener a l'echec de l'etablissement, independamment ou en parallele, dans un ecosysteme donne. [Traduit par la Redaction], Introduction Invasive species continue to pose staggering impacts on ecosystem structure and function (Mollot et al. 2017), raising questions about the circumstances that result in successful invasions. The number of [...]

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 [...]

Captive breeding programs are widely applied by conservation practitioners as a means of conserving, reintroducing, and supplementing populations of imperilled freshwater fishes and mussels. We conducted a systematic map to provide an overview of the existing literature on the effectiveness of captive breeding and release programs. A key finding is that there is limited evaluation of the effectiveness of such programs at all three stages (i.e., broodstock collection, rearing/ release methods, and post-release monitoring). We identified clusters of evidence for evaluating supplementation associated with rearing/release methods for fish growth and survival metrics, and the monitoring stage for fish genetic diversity, growth, and survival metrics, primarily focused on salmonids. However, many studies had inadequate experimental designs (i.e., lacked a comparator). Overall, there was a paucity of studies on the effectiveness of captive breeding programs for imperilled freshwater mussels, highlighting the need to make such information broadly available when studies are undertaken. Outputs from this systematic map (i.e., the map database and heatmaps) suggest that the effectiveness of captive breeding and release programs requires further systematic evaluation. Des programmes de reproduction en captivite sont largement utilises par les specialistes de la conservation comme moyen de conservation, de reintroduction et de supplementation de populations menacees de poissons d'eau douce et de mulettes. Nous avons realise une cartographie systematique pour dresser un portrait du corpus documentaire existant sur l'efficacite des programmes de reproduction en captivite et de lacher. Une des constatations cles est le fait que revaluation de l'efficacite des trois etapes de tels programmes (c.-a-d., prelevement de geniteurs, methodes d'elevage/de lacher et surveillance apres le lacher) est limitee. Nous avons cerne des groupements de donnees probantes pour les evaluations de la supplementation associees aux methodes d'elevage/de lacher pour des parametres relies a la croissance et la survie des poissons, et l'etape de surveillance pour des parametres relies a la diversite genetique, la croissance et la survie des poissons, axes principalement sur les salmonides. Le schema experimental de nombreuses etudes est toutefois inadequat (c.-a-d., absence de comparateur). Globalement, les etudes sur l'efficacite des programmes de reproduction en captivite pour les mulettes menacees sont rares, soulignant la necessite d'assurer une large disponibilite de ce type d'information quand de telles etudes sont realisees. Les extrants de cette cartographie systematique (c.-a-d., la base de donnees en decoulant et les cartes de densite) font ressortir la necessite d'une evaluation systematique plus poussee de l'efficacite de programmes de reproduction en captivite et de lacher. [Traduit par la Redaction], Introduction Global freshwater biodiversity has declined by over 80% since the 1970s, to the point where it is clearly in crisis (Harrison et al. 2018). Freshwater fishes have some of [...]

Reintroduction is an increasingly common conservation tool used to recover populations of imperilled species, but its success depends on the suitability of the introduced animals' phenotype for their new habitat. For fishes, thermal tolerance may be a key trait in urbanized habitats. We compared thermal tolerance (C[T.sub.max]) among three lineages (western, central, eastern) of imperilled redside dace (Clinostomus elongatus). C[T.sub.max] of eastern adults was 3-4[degrees]C lower than that of the other lineages, but adults of each lineage had similar thermal acclimation responses. In contrast, the acclimation response of juveniles differed by ~80% between the central and western lineages. Using these data, we predicted how each lineage would fare in a hypothetical reintroduction to relatively warm urbanized habitats. Owing to the differences in juvenile acclimation responses, predicted thermal safety margins for the central lineage were double those predicted for the western lineage. Overall, we suggest that C[T.sub.max] is a useful trait to incorporate into the source population selection process; however, there is an urgent need for the establishment of captive experimental research populations of imperilled species to address remaining uncertainties. Si la reintroduction est un outil de conservation de plus en plus utilise pour soutenir le retablissement de populations d'especes menacees, il faut, pour assurer son succes, que le phenotype des animaux introduits convienne a leur nouvel habitat. Pour les poissons, la tolerance a la chaleur pourrait etre un caractere cle dans les habitats urbanises. Nous avons compare la tolerance a la chaleur (C[T.sub.max]) de trois lignees (de l'Ouest, centrale et de l'Est) de menes longs (Clinostomus elongatus), une espece menacee. La C[T.sub.max] d'adultes de l'Est est de 3-4[degrees]C plus basse que celle des autres lignees, mais les adultes des trois lignees presentent des reactions d'acclimatation thermique semblables. En revanche, une difference de ~80 % est relevee entre les reactions d'acclimatation des juveniles des lignees centrale et de l'Ouest. En utilisant ces donnees, nous predisons comment chacune des lignees repondrait a la reintroduction hypothetique dans des habitats urbanises relativement chauds. En raison des differences de reaction d'acclimatation des juveniles, les marges de securite thermique predites pour la lignee centrale sont deux fois plus grandes que les marges predites pour la lignee de l'Ouest. Globalement, nous suggerons que la C[T.sub.max] est un caractere important a incorporer au processus de selection de populations sources; toutefois, il existe un besoin urgent d'etablir des populations de recherche experimentale en captivite d'especes menacees pour etudier les sources d'incertitude qui demeurent. [Traduit par la Redaction], Introduction Fisheries management has a long history of using translocations (moving wild fish from one place to another) and captive breeding programs to augment and expand natural populations of commercially [...]

The use of translocations to recover populations requires a sufficiently large number of individuals from source populations, but removing too many individuals could lead to source population collapse. To understand the trade-off between the probabilities of source population extirpation and translocation success, matrix population models that incorporate Allee effects, density dependence, and demographic and environmental stochasticity were combined with a model that simulates removals from source populations. We apply these models to eastern sand darter (Ammocrypta pellucida; Species at Risk Act status: Threatened) translocation scenarios in Canada. The results suggest that translocations most often require source populations >20 000 individuals, as source population extirpation probability increased with the number and frequency of removals. Transport mortality or losses immediately following introduction further affected translocation success. Uncertainty around life-history parameters and the strength of Allee effects led to additional uncertainty about the required source population size. Although stochastic processes affected the probability of translocation success, factors such as stocking density and frequency can be controlled, and translocation may therefore be a viable strategy for eastern sand darter recovery, even when applying cautious thresholds to guard against uncertainty. Si l'utilisation de deplacements pour retablir des populations necessite un nombre suffisamment grand d'individus de populations sources, le retrait de trop d'individus peut mener a l'effondrement de ces populations. Pour comprendre le compromis entre les probabilites de disparition de populations sources et le succes du deplacement, des modeles demographiques matriciels qui integrent des effets Allee, la dependance a la densite et une stochasticite demographique et environnementale ont ete combines a un modele qui simule des retraits de populations sources. Nous appliquons ces modeles a des scenarios de deplacement de dards de sable (Ammocrypta pellucida; etat de la Loi sur les especes en peril: menaces) au Canada. Les resultats donnent a penser que les deplacements necessitent le plus souvent des populations sources de plus de 20 000 individus, puisque la probabilite de disparition d'une population source augmente parallelement au nombre et a la frequence des retraits. La mortalite liee au transport ou les pertes immediatement apres l'introduction ont egalement une incidence sur le succes du deplacement. L'incertitude entourant des parametres du cycle biologique et la force d'effets Allee accroissent l'incertitude associee a la taille requise des populations sources. Bien que des processus stochastiques aient une incidence sur la probabilite de succes du deplacement, des facteurs comme la densite et la frequence d'ensemencement peuvent etre controles, de sorte que le deplacement pourrait etre une strategie viable pour le retablissement du dard de sable, meme si des seuils prudents sont appliques pour contrer l'effet de l'incertitude. [Traduit par la Redaction], Introduction The number of species that are currently at heightened risk of extinction continues to rise (Chapin et al. 2000; Rockstrom et al. 2009). Reversing this trend requires rigorous evaluation [...]

In data-poor regions, modeled river temperatures are essential for predicting potential stressors for species at risk. With limited data from the Grand, Thames, and Sydenham rivers in southern Ontario, Canada, we evaluated simple mixed-effect regression models to predict water temperature using air temperature from nearby weather stations. Model performance was assessed for periods relevant to the fitness of the black redhorse (Moxostoma duquesni): June to August, when heat events may be likely; and May, when spawning occurs. All of the models performed better when trained on data from these periods, compared with using data from the entire growing season. The best model was a linear regression using 5 days of lagged air temperature. This model had a root mean square error for summer means of 1.5[degrees]C. The differences in prediction error at different times of year highlight the importance of considering species ecology in model interpretation. However, the improvement in model fit when using only data from the relevant time of year suggests that relatively simple models can be used effectively in a management arena when applied appropriately. Dans les regions pour lesquelles peu de donnees sont disponibles, les temperatures modelisees des rivieres sont d'importance fondamentale pour la prediction de facteurs de stress potentiels pour les especes en peril. A partir de donnees limitees pour les rivieres Grand, Thames et Sydenham, dans le sud de l'Ontario (Canada), nous avons evalue des modeles de regression a effets mixtes simples pour la prediction des temperatures de l'eau a partir de temperatures de l'air mesurees a des stations meteorologiques a proximite. La performance des modeles a ete evaluee pour des periodes importantes pour l'aptitude du chevalier noir (Moxostoma duquesnii), soit de juin a aout, quand des episodes de chaleur sont probables, et en mai, quand le frai a lieu. Tous les modeles ont donne de meilleurs resultats quand ils etaient prealablement entraines avec des donnees pour ces periodes que lorsque des donnees pour toute la saison de croissance etaient utilisees. Le meilleur modele est une regression lineaire integrant cinq jours de donnees de temperatures de l'air decalees (ecart-type moyen estival 1,5[degrees]C). Les differentes erreurs de prevision a differents moments de l'annee soulignent l'importance de tenir compte de l'ecologie de l'espece pour l'interpretation des modeles. L'amelioration du calage sur les modeles que produit l'utilisation de donnees seulement pour les periodes importantes de l'annee donne cependant a penser que, s'ils sont bien appliques, des modeles relativement simples peuvent etre utilises efficacement en gestion. [Traduit par la Redaction], Introduction Water temperature is one of the primary factors that determine the survival, growth, and reproduction of aquatic organisms in flowing systems (Wismer and Christie 1987; Caissie 2006; Hasnain et [...]

More than 15 years have passed since Canada's Species at Risk Act was enacted. To evaluate scientific progress in support of the Act, we identified research accomplishments up to 2017 for imperilled aquatic species in the Great Lakes--St. Lawrence River basin based on recovery documents and an expert survey, spanning 1182 activities across 68 research topics for 45 fish and mussel species. Greatest progress was observed for population ecology (38% of activities with major progress) and habitat science (28%), with comparably less progress on threats (mechanisms and impacts; 19%) and recovery (threat mitigation and reintroduction; 21%). As a result of lagging progress, threat and reintroduction topics were prioritized for a Canadian Freshwater Species at Risk Research Network (SARNET; 2017-2020), which focused on addressing key knowledge gaps with novel applications. This special issue outlines the SARNET projects, which span novel field, laboratory, and analytical activities. Continued research investment into novel and existing approaches is necessary to advance scientific achievements for fishes and mussels in support of the Species at Risk Act in Canada. Plus de 15 annees se sont ecoulees depuis la promulgation de la Loi sur les especes en peril du Canada. Afin d'evaluer les avancees scientifiques a l'appui de la loi, nous avons recense les realisations en recherche jusqu'en 2017 touchant aux especes aquatiques menacees dans le bassin des Grands Lacs et du fleuve Saint-Laurent a la lumiere de documents concernant le retablissement et d'un sondage aupres de specialistes qui couvrent 1182 activites portant sur 68 sujets de recherche visant 45 especes de poissons et de moules. Les plus grandes avancees sont observees dans les domaines de l'ecologie des populations (38 % des activites presentant des avancees majeures) et de la science des habitats (28 %), relativement moins d'avancees etant observees dans les domaines des menaces (mecanismes et impacts, 19 %) et du retablissement (attenuation des menaces et reintroduction, 21 %). Au vu du retard au plan des avancees, les themes des menaces et de la reintroduction ont ete priorises pour un reseau canadien de recherche sur les especes d'eau douce en peril (SARNET, 2017-2020), dont les travaux ont mis l'accent sur d'importantes lacunes dans les connaissances offrant de nouvelles applications. Le present numero special offre un aperqu des projets du SARNET, qui portent sur un eventail d'activites analytiques, de terrain et de laboratoire originales. Un investissement soutenu en recherche sur des approches nouvelles et existantes est necessaire a la poursuite d'avancees scientifiques concernant les poissons et les moules, a l'appui de la Loi sur les especes en peril au Canada. [Traduit par la Redaction], Introduction The United Nations Convention on Biological Diversity (CBD) was established in 1992 to recognize the profound value of protecting biodiversity. The global response to the CBD was substantial, with [...]

We project how human population change (2018 to 2046) and aquatic invasive species (AIS) establishment events of bigheaded carps (Hypophthalmichthys spp.) and grass carp (Ctenopharyngodon idella) might combine to affect future Canadian recreational fishing activity for the Laurentian Great Lakes. Human population change is expected to affect the total number of fishing trips (increase of about 143 000 trips or 11.4%) more than any of the AIS establishment events (maximum decrease of about 44 000 trips or 3.5%). The projected 11.4% increase to the number of fishing trips from human population change, however, lags the 38% projected increase to Ontario, Canada's population from 2018 to 2046. Increasing urbanization and an aging population, which are associated with reduced rates of fishing participation, were responsible for this difference. The combined effects of human population change and AIS establishment illustrate the importance of accounting for human population change as it reverses the conclusions and results in a projected net increase of between 92 000 and 125 000 in the number of fishing trips. The combined model also identifies potential growth areas for fishing such as shore fishing by urbanites on the western portion of Lake Ontario. Nous faisons des projections sur les effets de la combinaison de l'evolution de la population humaine (de 2018 a 2046) et des cas d'etablissement d'espece aquatique envahissante (EAE) de carpes a grosse tete (Hypophthalmichthys spp.) et d'amours blancs (Ctenopharyngodon idella) sur l'activite de peche sportive canadienne pour les Grands Lacs laurentiens. Il est predit que l'evolution de la population humaine aura une plus grande incidence sur le nombre total d'excursions de peche (augmentation d'environ 143 000 excursions ou 11,4 %) que n'importe quel etablissement d'EAE (diminution maximum d'environ 44 000 excursions ou 3,5 %). Cependant, l'augmentation projetee de 11,4 % du nombre d'excursions de peche decoulant de l'evolution de la population humaine ne suit pas l'augmentation projetee de 38 % de la population de l'Ontario (Canada) de 2018 a 2046. L'urbanisation accrue et le vieillissement de la population, qui sont associes a des baisses des taux de participation a la peche, expliquent cet ecart. Les effets combines de l'evolution de la population humaine et de l'etablissement d'EAE illustrent l'importance de tenir compte de l'evolution de la population humaine, puisqu'elle inverse les conclusions et se traduit en une augmentation nette projetee de l'ordre de 92 000 a 125 000 du nombre d'excursions de peche. Le modele combine permet aussi de cerner des secteurs de croissance potentielle de la peche, comme la peche a terre par des citadins dans la partie ouest du lac Ontario. [Traduit par la Redaction], Introduction Recreational fisheries are defined and influenced by aquatic resources and people. While researchers frequently examine how changes to aquatic resources affect outcomes for recreational fisheries, much less attention is [...]

When considering the management of asymmetry, volume deficiency, scarring and vermillion notching following cleft lip repair, surgical techniques are commonly applied. However, surgery may not be suitable for all patients. Hyaluronic acid (HA) is a common, non-permanent filler widely used in non-surgical aesthetic practice. We present our unit's two-year experience of the regular use of HA filler in a dedicated Adult Cleft Facial Augmentation Clinic. Methods: Retrospective case note review was undertaken of all patients treated in the clinic over a two-year period. Results: 20 patients underwent HA filler injections to the upper lip 26 times. Most were female (F:M = 3:1) and patients were aged 18-58 years. Most patients had a unilateral cleft lip +/− palate (n = 13, 65%). The most common indication was to address upper lip volume (n = 13, 65%). Other indications included vermillion notch (n = 5, 25%), cupid bow peak height asymmetry (n = 4, 20%), scar asymmetry (n = 1, 5%) and nasal sill flattening (n = 1, 5%). Small volumes of filler were used with an average of 0.34 ml (range 0.05-1.2 ml). There were no complications and one patient reported pruritis post procedure. Conclusions: HA filler is a safe and reliable treatment for certain aspects of asymmetry following cleft lip repair. It can be used to address volume deficiency and asymmetry, cupid bow peak height discrepancies and a vermillion notch for patients who do not want surgery. Injection of HA to the lips can be performed easily, with appropriate training, in the outpatient setting. [ABSTRACT FROM AUTHOR]

Anthropogenic stressors such as agriculture and urbanization can increase river turbidity, which can negatively impact fish gill morphology and growth due to reduced oxygen in the benthic environment. We assessed the gill morphology, field metabolic rate (FMR), and two hypoxia tolerance metrics (oxygen partial pressure at loss of equilibrium, PO2 at LOE, and critical oxygen tension, Pcrit) of eastern sand darter (Ammocrypta pellucida), a small benthic fish listed as threatened under the Species at Risk Act in Canada, from rivers in southern Ontario. Field trials were conducted streamside in the Grand River (August 2019; mean NTU 8) and in the comparatively more turbid Thames River (August 2020; mean NTU 94) to test the effect of turbidity on each physiological endpoint. Gills were collected from incidental mortalities and museum specimens, and were assessed using hematoxylin and eosin and immunofluorescent staining. The between‐river comparison indicated that turbidity significantly increased interlamellar space and filament width but had no significant influence on other gill morphometrics or FMR. Turbidity significantly increased PO2 at LOE (i.e., fish had a lower hypoxia tolerance) but did not significantly impact Pcrit. Therefore, although turbidity influences hypoxia tolerance through LOE, turbidity levels were not sufficiently high in the study rivers to contribute to measurable changes in gill morphology or metabolism in the wild. Determining whether changes in gill morphology or metabolism occur under higherturbidity levels would help resolve the ecological importance of turbidity on species physiology in urban and agricultural ecosystems. [ABSTRACT FROM AUTHOR]

Introduction: The aim of unilateral cleft lip repair is to restore form and function, including symmetrisation of cleft and non-cleft philtral height. Expectation of best outcome is achieved in situations with minimal asymmetry and is assumed occurs most often in incomplete cleft lip only patients. We sought to investigate philtral height discrepancy (PHD) in children with unilateral cleft lip + /-palate from a single nation cohort. Methods: Review of prospectively collected PHD measurements taken at time of surgery for all children undergoing unilateral cleft lip repair in Scotland born Jan 2017—December 2020. Data was collected using Microsoft Excel and analysed using embedded statistical software. Results: 102 consecutive patients with unilateral lip involvement were identified from the national database. 94 had prospectively documented PHD (92.2%). The majority of patients had an isolated cleft lip (51.1%). Incomplete clefts presented more frequently (52.1%) than complete clefts (47.9%). Mean PHD for the whole cohort was 3.91mm (standard deviation 1.01mm, range 1–6mm). The difference in mean PHD (in-complete versus complete) was 1.1mm (3.4 vs. 4.5, p < 0.001). For lip only versus lip and palate the difference in mean PHD was 1.0mm (3.4 vs. 4.4, p < 0.001). Conclusions: This single country consecutive cohort review of PHD in children undergoing unilateral cleft lip repair statistically supports the anecdote that patients with an incomplete cleft lip and isolated cleft lip have lesser asymmetry at presentation. This study presents a consecutive cohort with a greater range of PHD than has previously been reported in the literature. [ABSTRACT FROM AUTHOR]

The focus and inclusion of gay men in academic literature has fluctuated throughout the years. The purpose of the present rapid review was to establish the predominant discourses and research [...]