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Moncton, Canada

The Maurice Lamontagne Institute is a marine science research institute located in Mont Joli, Quebec and is part of the Canadian Department of Fisheries and Oceans.Researchers at the institute have access to the following vessels:CCGS Calanus IICCGS Frederick G. CreedCCGS Martha L. BlackCCGS Alfred NeedlerCCGS HudsonCCGS Teleost Wikipedia.

Lacroix G.L.,Canadian Department of Fisheries and Oceans
Canadian Journal of Fisheries and Aquatic Sciences | Year: 2013

Pop-up satellite archival tags identified differences in oceanic migration of Atlantic salmon (Salmo salar) kelts from three distinct Canadian populations. Kelts from two endangered populations were restricted to coastal areas near home rivers, whereas kelts from a persisting nearby population migrated to the Labrador Sea and towards the Flemish Cap. Kelts spent most time near the surface (0-5 m), but coastal migrants undertook repeated daytime dives (10-40 m), associated with feeding, upon marine entry and progress was slow (8-23 km·day-1). Distant migrants moved rapidly along the continental shelf (10- 50 km·day-1) against prevailing ocean currents, remaining near the surface, except for deep dives (100-1000 m) when crossing ocean channels and at the shelf edge. Home range water temperatures (0-15 °C) indicated that kelts avoided warmer adjacent areas in summer. Kelts did not avoid cold coastal habitat (0-5 °C) in winter, but avoided the surface layers. Kelt migration mimicked that of postsmolts of similar origins, with water temperature acting as a directive or controlling factor. Containment of kelts from endangered populations in coastal habitat was probably responsible for the disappearance of repeat spawners.

Lacroix G.L.,Canadian Department of Fisheries and Oceans
Canadian Journal of Fisheries and Aquatic Sciences | Year: 2013

The migration of wild and hatchery Atlantic salmon (Salmo salar) postsmolts of different origins was monitored using ultrasonic tags and arrays of acoustic receivers across the Bay of Fundy (BoF), Canada. Postsmolts from outer BoF populations migrated rapidly into the Gulf of Maine (GoM) and did not return, and most were classified as distant migrants (77%-100%). In contrast, postsmolts from inner BoF populations were usually classified as coastal migrants that returned to the BoF for the summer (30%-90%). They used well-defined migration corridors, close to shore, associated with prevailing surface currents. An Akaike information criterion (AIC) evaluation of migration models identified region and watershed, date of river exit, and migration speed as important predictive variables for coastal residency. A late or slow migration increased residency, as did delaying hatchery releases. The BoF provided returning postsmolts with a summer thermal refuge (8-14 °C) encircled by warm water (>20 °C), but extended residency in this coastal habitat increased exposure to sources of mortality absent further at sea. This reduced marine survival of inner BoF salmon to almost nothing. It is likely that the different migratory strategies of inner and outer BoF salmon populations influenced their relative marine survival and endangered status.

Whitney F.A.,Canadian Department of Fisheries and Oceans
Geophysical Research Letters | Year: 2015

Wind-driven transport from the North Pacific in winter provides nutrients to a highly productive region in the transition zone between the subarctic and subtropics. This region supports many species of fish, marine mammals, and seabirds. In winter 2013/2014, anomalous winds from the south weakened nutrient transport in the eastern North Pacific, resulting in substantial decreases in phytoplankton biomass. By January 2014, waters were warmer than usual by 3.5°C at the center of an affected area covering ∼1.5 × 106 km2. South of this area, winter chlorophyll levels dropped to the lowest levels seen since the Sea-viewing Wide Field-of-view Sensor satellite began taking measurements in 1997. It is anticipated that impacts will be felt in some fisheries and among migrating predators this coming year. © 2015. American Geophysical Union. All Rights Reserved.

Edwards A.M.,Canadian Department of Fisheries and Oceans
Ecology | Year: 2011

A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scalefree movement patterns that can be described by a single dimensionless parameter, the exponent μ of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: Inaccurate techniques were used to estimate μ, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent μ do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once thought, and are not suitable for use as ecosystem indicators for fisheries management, as has been proposed. © 2011 by the Ecological Society of America.

Chaput G.,Canadian Department of Fisheries and Oceans
ICES Journal of Marine Science | Year: 2012

Since the early 1980s, the ICES Working Group on North Atlantic Salmon has collated and interpreted catch data, exchanged information on research initiatives, and provided advice to managers in support of conservation efforts for Atlantic salmon. During the past three decades, the annual production of anadromous Atlantic salmon from more than 2000 rivers draining into the North Atlantic has been less than 10 million adult-sized salmon. This represents a minor component, by number and biomass, of the pelagic ecosystem in the North Atlantic Ocean. Ideally, Atlantic salmon would be assessed and managed based on river-specific stock units, the scale that best corresponds to the spawner to recruitment dynamic. In reality, comparatively few river-specific assessments are available for either the Northwest or the Northeast Atlantic. The marine survival of Atlantic salmon is low and, based on return rates of smolts to adults from monitored rivers, has declined since the mid- to late 1980s. Abundance has declined more severely for the multi-sea-winter components, and especially in the southern areas of the species' range. Common patterns in abundance, inferred at the level of stock complex in the North Atlantic, suggest that broad-scale factors are affecting productivity and abundance and that they are acting throughout the salmon's time at sea. © 2012 Fisheries and Oceans Canada [2012]. Published by Oxford University Press.

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