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We investigated the response of Atlantic salmon (Salmo salar) to capture and handling stressors by analyzing fine-scale locomotor activity using accelerometer data loggers and broader-scale movements by tracking migration with radiotelemetry. Half the sample population was exposed to experimental exercise and air exposure and released with a control group to simulate fisheries handling. All but two of the surviving fish (both in the treatment group) returned to the counting fence to resume the 2016 spawning migration (survival = 86%-91%). There were no differences in postrelease locomotor activity, measured by an index of total body action (jerk), between control and treatment salmon (p = 0.81). Comparison of mean time to return to the counting fence against a null model revealed that treatment salmon were significantly delayed in returning to the counting fence (p < 0.01), whereas control fish were not (p = 0.24). Both the abiotic environment and human interactions influenced locomotor activity of the migratory fish and synchrony of the migration with untreated conspecifics. Nous avons etudie la reaction des saumons atlantiques (Salmo salar) a des stresseurs associes a la capture et a la manipulation par l'analyse de l'activite locomotrice fine en utilisant des enregistreurs de donnees d'accelerometre et des deplacements a plus grande echelle en suivant la migration par radiotelemetrie. La moitie de la population etudiee a ete exposee a l'exercice experimental et a l'air et relachee avec un groupe temoin afin de simuler la manipulation associee a la peche. Tous les poissons ayant survecu sauf deux (tous deux dans le groupe traite) sont retournes a la barriere de denombrement pour reprendre la migration de frai de 2016 (taux de survie = 86 %-91 %). Il n'y avait pas de difference sur le plan de l'activite locomotrice apres le lacher, mesuree par un indice de l'action corporelle totale (saccade), entre les saumons temoins et les saumons traites (p = 0,81). La comparaison du temps moyen avant le retour a un modele nul revele que le retour des saumons traites a la barriere de denombrement etait significativement retarde (p < 0,01), alors que celui des poissons temoins de l'etait pas (p = 0,24). Le milieu abiotique et les interactions avec les humains ont tous deux influence l'activite locomotrice des poissons migrateurs et la synchronisation de la migration avec celle de conspecifiques non traites., Introduction Migration is a large-scale (relative to the size of a given animal) synchronized movement of animals across a landscape between habitats, which allows them to optimize lifetime reproductive potential [...]

Aquatic animals are integral to ocean and freshwater ecosystems and their resilience, are depended upon globally for food sustainability, and support coastal communities and Indigenous peoples. However, global aquatic environments are changing profoundly due to anthropogenic actions and environmental change. These changes are altering distributions, movements, and survival of aquatic animals in ways that are not well understood. The Ocean Tracking Network (OTN) is a global partnership that is filling this knowledge gap. OTN Canada, a pan-Canadian (and beyond) research network, was launched in 2010 with visionary funding by the Canadian government. In our introduction to this special issue, we briefly overview how this interdisciplinary network has used state-of-the-art technologies, infrastructure, electronic tags and sensors, and associated cutting-edge research and training programs to better understand changing marine and freshwater dynamics and their impact on ecosystems, resources, and animal ecology. These studies have provided unprecedented insights into animal ecology and resource management at a range of spatial and temporal scales and by interfacing animal movements with novel measures of environment, physiology, disease, genetics-genomics, and anthropogenic stressors. Les animaux aquatiques sont des elements essentiels des ecosystemes oceaniques et d'eau douce et de la resilience de ces systemes, ils assurent la perennite de la disponibilite de nourriture a l'echelle planetaire et supportent des collectivites cotieres et des peuples autochtones. Les milieux aquatiques planetaires font toutefois l'objet de modifications profondes causees par l'activite humaine et des changements environnementaux. L'incidence de ces modifications sur la repartition, les deplacements et la survie des animaux aquatiques n'est pas bien comprise. L'Ocean Tracking Network (OTN) est un partenariat international qui vise a combler ces lacunes dans les connaissances. OTN Canada, un reseau de recherche pancanadien (et au-dela) a ete lance en 2010 grace au financement visionnaire du gouvernement du Canada. Dans notre introduction au present numero special virtuel, nous presentons un bref survol de l'emploi fait par ce reseau interdisciplinaire des plus recentes technologies, infrastructures, des etiquettes et capteurs electroniques et de la recherche et des programmes de formation de pointe associes pour mieux comprendre la dynamique changeante des milieux marins et d'eau douce et son incidence sur les ecosystemes, les ressources et l'ecologie animale. Ces etudes jettent un eclairage sans precedent sur l'ecologie animale et la gestion des ressources a differentes echelles spatiales et temporelles, en reliant les deplacements d'animaux a de nouvelles mesures du milieu, de la physiologie, des maladies, de la genetique-genomique et de facteurs de stress d'origine humaine., Introduction Aquatic animals help meet global food needs, annually contribute billions of dollars in socioeconomic benefits and ecosystem services to society, support coastal communities, and are culturally important, particularly for [...]

Like many deeper ocean species, the fine-scale movement ecology of snow crab is not well understood. We integrated fine-scale positioning telemetry with larger-scale position estimates from autonomous mobile surveys and harvester returns to evaluate movements of male and female snow crab (Chionoecetes opilio). Effects of life stage-sex, temperature, and diel and tidal cycles on movement velocity were observed, with a tendency for increased velocities during the night, slack tide, and at increasing water temperatures. Males also moved faster than females and juveniles. The strength of these statistical relationships, however, was weak ([R.sup.2] = 7.2%). The movement direction also did not vary over the tidal cycle. The maximum distance moved for adult males was an order of magnitude higher (37.1 km) than for females (3.6 km) and juvenile males (3.9 km), but median distances were more similar across groups. Individuals, once released, tended to disperse and move toward slope habitats. Little evidence of site fidelity was apparent. The absence of strong environmental influences on movements likely reflected the behavioural plasticity of snow crab and the relative environmental stability of offshore environments.A l'instar de celle de nombreuses especes oceaniques d'eau profonde, l'ecologie des deplacements a petite echelle du crabe des neiges n'est pas bien comprise. Nous avons combine des donnees de telemetrie de positionnement a echelle fine a des estimations de l'emplacement a plus grande echelle tirees de releves mobiles autonomes et de debarquements de pecheurs pour evaluer les deplacements de crabes des neiges (Chionoecetes opilio) males et femelles. Des effets de la combinaison du sexe et de l'etape du cycle biologique, de la temperature et des cycles nycthemeraux et tidaux sur la vitesse de deplacement ont ete observes, dont une tendance vers des vitesses plus grandes durant la nuit et l'etale et a de plus hautes temperatures de l'eau. Les males se deplacaient aussi plus rapidement que les femelles et les juveniles. Ces relations statistiques sont toutefois faibles (R2 = 7,2 %). En outre, la direction des deplacements ne variait pas durant le cycle de maree. La distance de deplacement maximum pour les males adultes etait un ordre de grandeur plus elevee (37,1 km) que celle des femelles (3,6 km) et des males juveniles (3,9 km), les distances medianes des trois groupes etant cependant plus semblables. Une fois relaches, les individus avaient tendance a se disperser et se deplacer vers des habitats de pente. Peu d'indices de fidelite au site ont ete notes. L'absence d'influences environnementales fortes sur les deplacements reflete vraisemblablement la plasticite comportementale des crabes des neiges et la relative stabilite environnementale des milieux extracotiers. [Traduit par la Redaction], IntroductionEcological and behavioural traits of most marine species are not well understood, including for many heavily managed, commercially important fisheries stocks. Often, fundamental research to understand a species' full life [...]

The potential for telemetry data to answer complex questions about aquatic animals and their interactions with the environment is limited by the capacity to store, manage, and access data across the research community. Large telemetry networks and databases exist, but are limited by the actions of researchers to share their telemetry data. Promoting data sharing and understanding researchers' views on open practices is a major step toward enhancing the role of big data in ecology and resources management. We surveyed 307 fish telemetry researchers to understand their perspectives and experiences on data sharing. A logistic regression revealed that data sharing was positively related to researchers with collaborative tendencies, who belong to a telemetry network, who are prolific publishers, and who express altruistic motives for their research. Researchers were less likely to have shared telemetry data if they engage in radio and (or) acoustic telemetry, work for regional government, and value the time it takes to complete a research project. We identify and provide examples of both benefits and concerns that respondents have about sharing telemetry data. Le potentiel que presentent les donnees de telemetrie pour repondre a des questions complexes sur les animaux aquatiques et leurs interactions avec le milieu est limite par la capacite de stocker et de gerer les donnees et de les rendre accessibles a l'ensemble des chercheurs. De grands reseaux et ensembles de donnees de telemetrie existent, mais ils sont limites par les mesures que prennent les chercheurs pour partager leurs donnees. La promotion du partage de donnees et la comprehension des perspectives des chercheurs sur les pratiques ouvertes constituent un pas important vers l'accroissement du role des donnees massives en ecologie et en gestion des ressources. Nous avons sonde 307 chercheurs qui utilisent la telemetrie pour etudier les poissons afin de comprendre leurs points de vue et experiences en matiere de partage de donnees. Une regression logistique revele que le partage de donnees est positivement relie aux chercheurs ayant tendance a collaborer, qui font partie d'un reseau de telemetrie, qui publient abondamment et qui mentionnent des raisons altruistes motivant leurs travaux. Les chercheurs sont moins susceptibles d'avoir partage des donnees de telemetrie s'ils font de la radiotelemetrie ou de la telemetrie acoustique, travaillent pour un gouvernement regional et accordent de la valeur au temps necessaire pour realiser un projet de recherche. Nous avons cerne des avantages et preoccupations souleves par les repondants concernant le partage de donnees de telemetrie et en presentons des exemples. [Traduit par la Redaction], Introduction Telemetry is an extraordinary tool for monitoring animal movement in the wild, with applications in the aquatic, aerial, and terrestrial realms (Cooke et al. 2004; Hussey et al. 2015; [...]

ABSTRACT Eye numbers were quantified on the mantles of sea scallops (Placopecten magellanicus) to determine whether they varied with scallop size (correlated with age), and to compare the numbers of [...]

Acoustic telemetry is a useful tool to monitor the estuarine survival and behaviour of Atlantic salmon postsmolts. Most frequently, survival is reported as the static fraction of tagged postsmolts detected, and while the timing or location of mortality may be reported, covariates of survival or the relationship between migratory behaviour and survival are less often described. In this study, we used acoustic telemetry to follow Atlantic salmon smolts migrating to sea from four rivers in Nova Scotia, Canada. Further, we tested the relationship between migratory behaviour and survival and used mark-recapture models to examine the role of body length and tag-to-body mass as survival covariates. Survival was most heavily impacted in estuarine habitats closest to head-of-tide. Survival was affected by body length at three of four sites. The shape and spatial variability of the body length--survival relationship provided insight on mortality vectors, highlighting the potential roles of predation and osmotic stress. Survival was not influenced by repeated landward-seaward migratory movements; however, there was a significant correlation between residency and survival. La telemetrie acoustique est un outil utile pour la surveillance de la survie et du comportement en estuaire des post-saumoneaux de saumon atlantique. Dans la plupart des cas, le taux de survie signale est la fraction statique de postsaumoneaux marques detectes et, si le moment et le lieu de la mortalite peuvent etre mentionnes, les covariables du taux de survie ou de la relation entre le comportement migratoire et la survie sont moins souvent rapportees. Dans cette l'etude, nous avons fait appel a la telemetrie acoustique pour suivre des saumoneaux de saumon atlantique en migration de la mer vers quatre rivieres de la Nouvelle-Ecosse (Canada). Nous avons en outre verifie le lien entre le comportement migratoire et le taux de survie et utilise des modeles de marquage-recapture pour examiner la longueur du corps et le rapport entre le poids de la marque et celui du corps comme covariables eventuelles du taux de survie. Les impacts sur ce dernier etaient les plus forts dans les habitats estuariens situes les plus pres de la limite de maree. Dans quatre sites, la longueur du corps avait une incidence sur le taux de survie. La forme et la variabilite spatiale de la relation entre la longueur du corps et le taux de survie ont mis en lumiere des vecteurs de mortalite, faisant ressortir un role possible de la predation et du stress osmotique. Si les deplacements migratoires repetes vers la terre ou vers la mer n'avaient pas d'incidence sur le taux de survie, une correlation significative a cependant ete notee entre le temps de residence et le taux de survie. [Traduit par la Redaction], Introduction Atlantic salmon (Salmo salar L.) populations within the southern portion of their North American range have declined dramatically (Parrish et al. 1998; WWF 2001; COSEWIC 2011), due in large [...]

Knowledge of the prevalence of escaped farmed fishes in the wild is an essential first step to assessing the risk resulting from interactions between farmed and wild fishes. This is especially important in eastern North America, where Atlantic salmon (Salmo salar) aquaculture occurs near wild Atlantic salmon rivers and where many wild salmon populations are severely depressed. Here, we review the literature on the incidence of escaped farmed salmon in eastern North American rivers, for which there has been no comprehensive compilation to date. Escaped farmed salmon have been found in 54 of 62 (87%) rivers investigated within a 300 km radius of the aquaculture industry since 1984, including 11 rivers that contain endangered salmon populations. Averaged among all investigations, the proportional representation of farmed salmon among adults entering the rivers from the sea was 9.2% (range 0% to 100%). Where data were sufficient to examine temporal trends, farmed salmon proportions varied considerably over time, suggesting that escape events are episodic in nature. We conclude that escaped farmed salmon are sufficiently prevalent in eastern North American rivers to pose a potentially serious risk to the persistence of wild salmon populations, especially in those rivers that are adjacent to existing aquaculture sites. Une evaluation de la prevalence des poissons echappes de pisciculture en nature est un premier pas essentiel dans la determination des risques relies aux interactions entre les poissons d'elevage et les poissons sauvages. La situation est particulierement serieuse dans l'est de l'Amerique du Nord ou des cultures de saumons atlantiques (Salmo salar) se retrouvent pres de rivieres a saumons atlantiques sauvages et ou plusieurs des populations de saumons sauvages sont considerablement reduites. Nous faisons ici une revue de la litterature sur l'incidence de poissons echappes de culture dans les rivieres de l'est de l'Amerique du Nord, dont il n'existe pas a ce jour de compilation exhaustive. On a trouve des saumons echappes de culture dans 54 des 62 (87 %) rivieres etudiees dans un rayon de 300 km de l'industrie piscicole depuis 1984, dont 11 rivieres contenant des populations de saumons en voie de disparition. Dans l'ensemble des inventaires, la proportion moyenne de saumons de pisciculture parmi les saumons qui penetrent dans les rivieres a partir de la mer est de 9,2 % (etendue: 0 % a 100 %). Dans les cas ou les donnees sont assez nombreuses pour permettre d'etudier les tendances temporelles, les proportions de saumons de pisciculture varient considerablement dans le temps, ce qui laisse croire que les incidents de fuites sont de nature episodique. Nous concluons que la prevalence de saumons echappes de pisciculture est suffisamment grande dans les rivieres de l'est de l'Amerique du Nord qu'elle represente une menace pour la persistance des populations de saumons sauvages, particulierement dans les rivieres qui sont a proximite de sites actuels d'aquaculture. [Traduit par la Redaction], Introduction Worldwide declines in wild fish stocks combined with a growing human population have resulted in increased demands for aquaculture production. Over 25% of the world's fish consumption is now [...]

Abstract: Brook char (Salvelinus fontinalis) exist in both freshwater and anadromous forms, often in sympatry, the ecology of the latter being poorly understood. As strontium (Sr) can substitute to calcium [...]

Three-spined stickleback, Gasterosteus aculeatus, males guarding nests containing eggs were tested for their use of distraction displays against all-male, all-female and mixed male and female conspecific intruder groups. Distraction displays were used against all groups, suggesting that the display is a foraging rather than a sexual deception. Most males used two different displays, with the most obvious being employed primarily when intruders were close to the nest. Males also buried their nests with sand to protect them. Groups with male members made more territorial intrusions and fought more with the residents than all-female groups. However, nest survival-to-hatching was better in mixed and all-male trials than all-female trials. Raiding caused most nest destructions, although suffocation following burying killed some eggs. The high nest survival-to-hatching in the all-male and mixed trials probably occurred because some male intruders established territories. This reduced the number of fish in raiding groups and resulted in joint attacks by several territorial fish on the remaining group members. Resident males could control the remaining fish with aggression. Males guarding nests without eggs also used distraction displays, but they did not bury their nests.