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The Great Lakes Acoustic Telemetry Observation System (GLATOS), organized in 2012, aims to advance and improve conservation and management of Great Lakes fishes by providing information on behavior, habitat use, and population dynamics. GLATOS faced challenges during establishment, including a funding agency-imposed urgency to initiate projects, a lack of telemetry expertise, and managing a flood of data. GLATOS now connects 190+ investigators, provides project consultation, maintains a web-based data portal, contributes data to Ocean Tracking Network's global database, loans equipment, and promotes science transfer to managers. The GLATOS database currently has 50+ projects, 39 species tagged, 8000+ fish released, and 150+ million tag detections. Lessons learned include (1) seek advice from others experienced in telemetry; (2) organize networks prior to when shared data is urgently needed; (3) establish a data management system so that all receivers can contribute to every project; (4) hold annual meetings to foster relationships; (5) involve fish managers to ensure relevancy; and (6) staff require full-time commitment to lead and coordinate projects and to analyze data and publish results. Le systeme d'observation par telemetrie acoustique des Grands Lacs (GLATOS), mis sur pied en 2012, vise a faire avancer et a ameliorer la conservation et la gestion des poissons des Grands Lacs en fournissant de l'information sur les comportements, l'utilisation des habitats et la dynamique des populations. GLATOS a fait face a differents defis durant son etablissement, dont l'urgence d'entreprendre des projets imposee par les organismes de financement, un manque d'expertise en telemetrie et la gestion d'une quantite massive de donnees. GLATOS relie aujourd'hui plus de 190 chercheurs, fournit des conseils sur des projets, maintient un portail de donnees sur le web, fournit des donnees a la base de donnees planetaire de l'Ocean Tracking Network, prete du materiel et fait la promotion du transfert des connaissances scientifiques aux gestionnaires. La base de donnees de GLATOS compte actuellement plus de 50 projets, 39 especes etiquetees, plus de 8000 poissons relaches et plus de 150 millions de detections d'etiquettes. Les lemons tirees comprennent l'importance (1) de demander les avis et conseils d'autres intervenants avec de l'experience en telemetrie, (2) d'organiser les reseaux avant que ne se presentent des besoins urgents d'echange des donnees, (3) d'etablir un systeme de gestion des donnees pour faire en sorte que tous les recepteurs puissent contribuer a tous les projets, (4) d'organiser des reunions annuelles pour renforcer les liens, (5) d'inclure les gestionnaires des peches pour assurer la pertinence des projets et (6) de prevoir le personnel a temps plein necessaire pour assurer la direction et la coordination des projets, l'analyse des donnees et la publication des resultats. [Traduit par la Redaction], Introduction Acoustic telemetry has become increasingly popular for investigating behavior, habitat preferences, and population dynamics of native and invasive fish in fresh and marine waters (e.g., Hussey et al. 2015; [...]

Bioenergetics modeling was used to assess the relative importance of food availability and water temperature in determining walleye (Sander vitreus) growth. Temperature regimes experienced by both female and male adult walleye in three basins of Lake Huron and in Lake Erie were determined by use of surgically implanted temperature loggers and acoustic telemetry. Temperatures experienced by walleye were higher in Lake Erie than in Lake Huron. Walleye from Lake Erie grew at nearly double the rate of walleye from Lake Huron, and mass at age for adult females averaged about 50% greater than that for adult males in both lakes. Food consumption rate for an average adult walleye in Lake Erie was nearly twice as high as that in Lake Huron. Interbasin and interlake variability in temperature regimes accounted for a moderate degree of variability in walleye growth. We concluded that the driver for faster growth in Lake Erie compared with Lake Huron was higher food availability in Lake Erie compared with Lake Huron. The sex difference in temperature regimes explained 15% of the sex difference in Lake Erie walleye growth. La modelisation de la bioenergetique a ete utilisee pour evaluer l'importance relative de la disponibilite de nourriture et de la temperature de l'eau comme facteurs determinants de la croissance des dores jaunes (Sander vitreus). Les regimes thermiques auxquels sont exposes les dores adultes femelles et males dans trois bassins du lac Huron et dans le lac Erie ont ete determines en utilisant des enregistreurs de temperature implantes chirurgicalement et la telemetrie acoustique. Les temperatures etaient plus elevees pour les dores dans le lac Erie que pour ceux dans le lac Huron. Le taux de croissance des dores du lac Erie etait presque le double de celui des dores du lac Huron, et le poids en fonction de l'age pour les femelles adultes etait en moyenne 50% superieur a celui des males adultes dans les deux lacs. Le taux de consommation de nourriture pour un dore adulte moyen dans le lac Erie etait presque deux fois plus grand que dans le lac Huron. La variabilite des regimes thermiques entre bassins et entre lacs explique un degre modere de variabilite de la croissance des dores. Nous concluons que le facteur expliquant la croissance plus rapide dans le lac Erie que dans lac Huron est une plus grande disponibilite de nourriture dans le lac Erie. La difference entre les sexes sur le plan des regimes thermiques explique 15% de la difference entre les sexes sur le plan de la croissance des dores du lac Erie. [Traduit par la Redaction], Introduction For a given species of fish, individual-level growth of fish is a function of food availability and the temperature regime experienced by the fish (Hewett and Johnson 1992; Jobling [...]

Thermoregulation is presumed to be a widespread determinant of behaviour in fishes, but has not often been investigated as a mechanism shaping long-distance migrations. We used acoustic telemetry and animal-borne thermal loggers to test the hypothesis that seasonal migration in adult walleye (Sander vitreus) in Lake Erie is size- and (or) sex-specific and related to behavioural thermoregulation. Female walleye migrated out of the warm, shallow western basin earlier than did males and were 1.8 times more likely to be detected on acoustic receivers in the deeper and cooler eastern basin. The few fish that remained in the western basin were restricted to a smaller range of higher temperatures ([greater than or equal to]20 [degrees]C) than those that migrated to the central and eastern basins (~16-21 [degrees]C). However, temperature records from walleye in the central basin were nearly indistinguishable from those in the eastern basin, suggesting thermal preferences alone could not explain migration to the eastern basin. As such, our effort to understand the mechanisms that cause migratory behaviours has generated mixed evidence on the role of temperature and that factors like foraging opportunities may have synergistic roles in the migration. S'il est presume que la thermoregulation est un determinant repandu du comportement chez les poissons, la possibilite qu'elle puisse moduler les migrations sur de longues distances n'a pas souvent ete examinee. Nous avons utilise la telemetrie acoustique et des enregistreurs de temperature installes sur des animaux pour verifier l'hypothese selon laquelle la migration saisonniere chez les dores jaunes (Sander vitreus) adultes du lac Erie depend de la taille ou du sexe et est associee a la thermoregulation comportementale. La migration des dores femelles pour sortir du bassin ouest plus chaud et moins profond a eu lieu plus tot que celle des males, et les femelles etaient 1,8 fois plus susceptibles d'etre detectees par des recepteurs acoustiques dans le bassin est plus profond et frais. Les quelques poissons qui etaient restes dans le bassin ouest etaient limites a une petite fourchette de temperatures plus elevees ([greater than or equal to]20 [degrees]C) que celles caracterisant les poissons ayant migre vers les bassins central ou est (~16-21 [degrees]C). Cependant, les registres de temperatures des dores dans le bassin central etaient presque identiques a ceux du bassin est, ce qui indiquerait que les preferences thermiques ne peuvent a elles seules expliquer la migration vers le bassin est. Ainsi, nos efforts visant a comprendre les mecanismes qui modulent les comportements migratoires ont fait ressortir des indications mitigees sur le role de la temperature et le fait que des facteurs comme les occasions d'approvisionnement pourraient jouer des roles synergiques dans la migration. [Traduit par la Redaction], Introduction Understanding why animals migrate is fundamental to ecology, evolution, and the conservation of migratory species and their habitat (Wilcove and Wikelski 2008). Migration can be driven by a variety [...]

The Gamma Ray Energy Tracking In-Beam Nuclear Array (GRETINA), capable of determining the energy and position (within 2 mm) of each gamma-ray interaction point and tracking multiple gamma-ray interactions, has been designed. GRETINA will be composed of seven detector modules, each with four highly pure germanium crystals. Each crystal has 36 segments and one central contact instrumented by charge sensitive amplifiers. Two custom designed modules, the Digitizer/Digital Signal Processing (DSP) and the Trigger Timing and Control, compose the electronics of this system. The Digitizer/DSP converts the analog information with 14-bit analog to digital converters (operating at 100 MS/s, and digitally processes the data to determine the energy and timing information of the gamma interactions with the crystal. Each Digitizer/DSP is controlled by and sends trigger information to the Trigger Timing & Control system through a bidirectional Gbit link. Presently four different trigger algorithms are planned for the trigger system and can be selected for trigger decision. In this paper the details of the electronics and algorithms of the GRETINA data acquisition and trigger system are presented and the performance is reviewed. Index Terms--Data acquisition systems, digital signal processing, gamma-ray spectrometer, trigger systems.

Fidelity to spawning habitats can maximise reproductive success of fish by synchronising movements to sites of previous recruitment. To determine the role of reproductive fidelity in structuring walleye Sander vitreus populations in the Laurentian Great Lakes, we used acoustic telemetry combined with Cormack-Jolly-Seber capture-recapture models to estimate spawning site fidelity and apparent annual survival for the Tittabawassee River in Lake Huron and Maumee River in Lake Erie. Walleye in spawning condition were tagged from the Tittabawassee River in Lake Huron and Maumee River in Lake Erie in 2011-2012. Site fidelity and apparent annual survival were estimated from return of individuals to the stream where tagged. Site fidelity estimates were higher in the Tittabawassee River (95%) than the Maumee River (70%) and were not related to sex or fish length at tagging. Apparent annual survival of walleye tagged in the Tittabawassee did not differ among spawning seasons but was higher for female than male walleye and decreased linearly as fish length increased. Apparent annual survival of walleye tagged in the Maumee River did not differ among spawning seasons but was higher for female walleye than male walleye and increased linearly as fish length increased. Greater fidelity of walleye tagged in the Tittabawassee River than walleye tagged in the Maumee River may be related to the close proximity to the Maumee River of other spawning aggregations and multiple spawning sites in Lake Erie. As spawning site fidelity increases, management actions to conserve population structure require an increasing focus on individual stocks. [ABSTRACT FROM AUTHOR]

Electronic tags have become a common tool in fish research, enhancing our understanding of how fish interact with their environment and move among different habitats, for estimating mortality and recording internal physiological states. An often-untested assumption of electronic tagging studies is that tagged fish are representative of untagged conspecifics and thus show 'normal' behaviour (e.g. movement rates, swimming activity, feeding). Here, we use a unique data set for potamadromous walleye ( Sander vitreus) in Lake Huron and Lake Erie tributaries to assess whether the lack of appropriate controls in electronic tagging could seriously affect behavioural data. We used fish tagged in previous years and compared their migratory behaviour during the spawning season to fish tagged in a current year at the same location. The objective of the study was to determine whether intracoelomic acoustic tag implantation altered downstream movement of walleye after spawning. Fish tagged in a given season travelled slower downstream from two river spawning sites than fish tagged in previous years. Fish tagged one or two years earlier showed no differences between each other in downstream travel time, in contrast to fish tagged in a given year. Our results support notions that standard collection and intracoelomic tagging procedures can alter short-term behaviour (i.e. days, weeks, months), and as such, researchers should use caution when interpreting data collected over such time periods. Further, whenever possible, researchers should also explicitly evaluate post-tagging effects on behaviour as part of their experimental objectives. [ABSTRACT FROM AUTHOR]