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Seasonal distribution of adult Atlantic sturgeon was examined using pop-up satellite archival tags (PSATs) and ultrasonic transmitters deployed in the Saint John River, New Brunswick, Canada. Seven MK10 PSATs programmed for release in June 2012 and seven MiniPAT PSATs programmed for release in February and April 2013 were deployed in August 2011 and 2012, respectively. Eleven of 14 PSATs surfaced and transmitted depth and temperature data archived for the duration of their deployment (121–302 days). Among these eleven PSATs, five were recovered and 15-sec archival data was downloaded. Following exit from the Saint John River in the fall, tagged fish occupied a mean monthly depth of 76.3–81.6 m at temperatures as low as 4.9˚C throughout the winter before returning to shallower areas in the spring. The majority of ultrasonic detections occurred in the Bay of Fundy, but fish were detected as far as Riviere Saint-Jean, Quebec, approximately 1500 km from the Bay of Fundy (representing long-distance migratory rates of up to 44 km/day). All PSATs were first detected in the Bay of Fundy. Tags that released in February and April were found 5–21 km offshore of the Saint John Harbour, while tags that released in June were first detected in near shore areas throughout the Bay of Fundy. The substrate at winter tag release locations (estimated from backward numerical particle-tracking experiments) consisted primarily of moraines and postglacial mud substrate with low backscatter strength, indicative of soft or smooth seabed. Based on the proximity of winter tag release locations, the consistent depths observed between fish, and previous research, it is suspected that a winter aggregation exists in the Bay of Fundy. This study expands the understanding of the marine distribution and range of Atlantic sturgeon on the east coast of Canada. [ABSTRACT FROM AUTHOR]

Twenty-three new, precise, Eocene U–Pb and [sup 40] Ar/[sup 39] Ar age determinations for calc-alkaline volcanic rocks of the Ootsa Lake Group and associated intrusive rocks, widespread in the Nechako Plateau in central British Columbia, constrain the timing of the Eocene magmatism to 53.2–47.6 Ma, with a local duration of as little as 2–3 million years. The new dates show that magmatism in the study area is partly coeval with that responsible for the Babine Igneous Suite – Newman Volcanic Suite (53–50 Ma) to the north, and for the Endako Group (51–45 Ma), which overlies the Ootsa Lake Group; however, locally the three magmatic suites are distinct in age and (or) the strata record a magmatic hiatus of as much as 7.5 million years. The ages generally young from north to south (52–47 Ma) along the western portion of the study area. The Babine Igneous Suite – Newman Volcanic Suite represents the oldest member of this series. However, in the east, the Ootsa Lake Group volcanic rocks are generally older (53–51 Ma). The anomalously older ages may be related to the interaction of magmatism and formation of a nearby and coeval core complex, which ongoing studies show was uplifted at about the same time during the Eocene. Felsic plutonism associated with the Ootsa Lake Group occurred between 50.5 and 47.3 Ma. These plutons were emplaced in an extensional setting along north-northeast-trending faults. The new dates, stratigraphic relationships, and suggested correlations of Eocene strata in the study area with that to the west and north require a revision of the stratigraphic nomenclature for the Ootsa Lake and Endako groups.Vingt-trois nouvelles déterminations d'âge, précises, U–Pb et [sup 40] Ar/[sup 39] Ar sur des roches volcaniques calco-alcalines du Groupe d'Ootsa Lake et des roches intrusives associées, datant de l'Éocène, largement répandues dans le plateau de Nechako au centre de la Colombie-Britannique, limitent le magmatisme à l'Éocène à 53,2–47,6 Ma et à une durée aussi courte que 2 à 3 millions d'années. Les nouvelles dates montrent que le magmatisme dans la région étudiée est en partie contemporain avec celui qui est responsable de la suite ignée Babine – suite volcanique Newman (53–50 Ma) vers le nord et du Groupe Endako (51–45 Ma) qui repose sur le Groupe d'Ootsa Lake; localement, les trois suites magmatiques sont toutefois distinctes en âge et (ou) les strates enregistrent un hiatus magmatique allant jusqu'à 7,5 Ma. Les âges sont généralement plus jeunes du nord vers le sud (52–47 Ma) le long de la partie occidentale de la région à l'étude. La suite ignée Babine – suite volcanique Newman représente le membre le plus âgé de cette série. Toutefois, vers l'est, les roches volcaniques du Groupe d'Ootsa Lake sont généralement plus âgées (53–51 Ma). Les âges anormalement plus vieux peuvent être reliés à l'interaction du magmatisme et à la formation, à proximité, d'un complexe noyau contemporain, lequel, selon des études en cours, s'est soulevé à peu près à la même époque, à l'Éocène. Le plutonisme felsique associé au Groupe d'Ootsa Lake aurait eu lieu il y a environ 50,5 à 47,3 Ma. Ces plutons ont été mis en place dans un environnement extensionnel le long de failles de direction nord-nord-est. Les nouvelles dates, les relations stratigraphiques et les corrélations suggérées pour les strates de l'Éocène dans la région à l'étude et celles vers l'ouest et le nord demandent une révision de la nomenclature stratigraphique pour les groupes d'Ootsa Lake et d'Endako.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]