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Walleye (Sander vitreus) populations in Alberta, Canada, collapsed by the mid-1990s and were a case study in the paper Canada's Recreational Fisheries: The Invisible Collapse? Here we fit age-structured population dynamics models to data from a landscape-scale monitoring program to assess walleye population status and reconstruct recruitment dynamics following the invisible collapse. Assessments indicated that populations featured low Fmsy values of approximately 0.2–0.3 under conservative assumptions for the stock–recruitment relationship but that many populations were lightly exploited during 2000–2018. Recruitment reconstructions showed that recovery from collapse in 33/55 lakes was driven in part by large positive recruitment anomalies that occurred during 1998–2002. Additionally, 15/55 lakes demonstrated cyclic recruitment dynamics. The documented recruitment anomalies and cyclic fluctuations could be due to environmental effect(s) or cannibalism, and experimentation is likely necessary to resolve this uncertainty. These findings contribute new information on the recovery dynamics of walleye following the invisible collapse and demonstrate the effectiveness of coupling traditional fisheries science models with broad-scale monitoring data to improve understanding of population dynamics and sustainability across landscapes. [ABSTRACT FROM AUTHOR]

There are more Pacific salmon in the ocean recently than in recorded history. Increases are believed to be related to shifts in climate but specific, biologically based mechanisms linking climate to increases are not known. At the same time, Pacific salmon abundances in Japan and on Canada's west coast are at historic low levels with attempts to stop the decline unsuccessful. Most juvenile salmon that enter the ocean die, resulting in large abundance increases and decreases from small changes in the already very low ocean survival. Because of this sensitivity to changes in ocean ecosystems and because of the recent basin-scale fluctuations in trends in abundance, I propose that it is time to see a bigger picture and improve the understanding of the biological mechanisms that most influence ocean survival. I leave it to readers to decide if my example of Pacific salmon is part of a more general need in fisheries science to better understand the biological mechanisms linking survival to climate. [ABSTRACT FROM AUTHOR]

The document provides a list of upcoming fisheries-related conferences and meetings taking place between January and March 2024. The events are held in various locations across the United States and Canada, covering topics such as aquaculture, fish and wildlife conservation, and ecosystem management. The conferences offer opportunities for professionals and researchers in the field to network, share knowledge, and discuss the latest developments in fisheries science and management. [Extracted from the article]

Advances in genetic and genomic technologies have become widely available and have potential to provide novel insights into fish biology and fisheries science. In the present overview, we explore cases for which genomic analyses have proven instrumental in the rejection of hypotheses that have been well-motivated based on phenotypic and ecological properties of individuals and populations. We focus on study systems for which information derived using genomic tools contradicts conclusions drawn from traditional fisheries science methodologies and assumptions. We further illustrate the non-intuitive interplay of genomics and ecology in Atlantic salmon (Salmo salar L.) owing to the recently detected genetic architecture of age at maturity in this species. To this end, we explore a salmon management strategy applied in Québec, Canada and find that management measures aimed at protecting large, old individuals can lead to unexpected and undesired outcomes. Finally, we envisage ways in which genomic tools could be used more effectively in contemporary fisheries research and how their application could illuminate the ecological and evolutionary drivers of species and ecosystem dynamics. [ABSTRACT FROM AUTHOR]

Thirty-nine years of scale growth measurements from Big Qualicum River chum salmon ( Oncorhynchus keta) in southern British Columbia demonstrated that competition and climate variation affect marine growth and age-at-maturity. A longitudinal study design that accounted for correlation among individuals revealed growth at all ages was reduced when the biomass of North American chum, sockeye ( Oncorhynchus nerka), and pink salmon ( Oncorhynchus gorbuscha) was high. When North Pacific Gyre Oscillation (NPGO) was positive, indicating increased primary productivity, predicted growth increased. Climate variation influenced competition effects. For instance, density-dependent competition effects increased when NPGO became more positive and Pacific Decadal Oscillation became more negative (indicating cool conditions), causing the greatest range in predicted scale size. Chum salmon are likely to exhibit continued reduction in growth at age due to increased ocean temperatures driven by climate change and high aggregate salmon biomass that includes hatchery releases. If evidence of biomass and climate effects presented here are common among Pacific salmon populations, reduction of hatchery releases should be considered. [ABSTRACT FROM AUTHOR]

By leading the Canadian Fisheries Expedition of 1914–1915 Johan Hjort took the opportunity to do far more than just survey herring, other fish stocks, and the hydrography of Canadian Atlantic waters. He also attempted to improve the backward fish-processing technologies used in the local fisheries, an agenda blocked by the Canadian government. Hjort did succeed markedly, however, in introducing Canadian scientists to the International Council for the Exploration of the Sea's new scientific methods for fisheries research. He and his colleagues offered training in the new dynamic oceanography as well as population demographic studies and biometrics for studying fish populations, races, and other units. His extroverted leadership-initiated lasting linkages between Canadian and Scandinavian scientists, and created an international network of fisheries biologists. [ABSTRACT FROM AUTHOR]

Fifty white sturgeon ( Acipenser transmontanus) eleutheroembryos (average size 0.17 g) were placed onto each of four quadrants (0.45 m2 quadrant−1; 200 fish tank−1) of different sized substrates in four circular tanks (approximately 562 L). Each of three quadrants had a different size substrate and the fourth quadrant was left bare. We used one replicate of smaller size substrates (0.5–11.9 mm) and one replicate of larger size substrates (21.7–88 mm). It was found that the white sturgeon eleutheroembryos preferred substrate with an average size (longest diameter) of 12 mm (11.9) in the smaller substrate range and 22 mm (21.7) in the larger substrate range. These data improve our knowledge of white sturgeon early life history, and if confirmed in the wild can be used to protect areas that are crucial for white sturgeon recruitment and survival. [ABSTRACT FROM AUTHOR]

The article discusses the graduate education opportunities in fisheries science in Canada and the U.S. as well as some of the issues that may influence students when they are making decisions about graduate schools. Some options for seeking graduate opportunities include reviewing papers of interest, contacting current graduate students, and searching the Web for online graduate postings. The main requirements of admission to a graduate program are a minimum grade point average (GPA) and approval from a potential supervisor.