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One of the world's pre‐eminent marine scientists and the founding editor of Fisheries Oceanography, Professor Timothy (Tim) R. Parsons, passed away peacefully in hospital in April 2022. He was passionate about building a holistic understanding of how pelagic organisms are interconnected in the food‐webs of the sea, and about presenting alternative methods for the management of fisheries. For these activities and many others, he was the recipient of many international awards and honours. He had a profound influence on many students and colleagues, and leaves behind a foundational body of work on fisheries oceanography. [ABSTRACT FROM AUTHOR]

Problems with spatial (geographical) and temporal scales in fisheries research and management have become better known over the past few years. However, technological and some institutional scales, along with essential contextual dimensions (policy, intellectual, and academic) are also important. We discuss fisheries management in general with respect to these matters and their interactions. We also provide recommendations for addressing these issues, both in general and with particular reference to local fisheries. These are: (1) recognize the importance of fishers' knowledge across all scales; (2) recognize fishers' motivations, especially at the local/community scale; (3) thus expand the nature of the information used for management; (4) match the spatial management scales to those of the fish and the fishers; (5) recognize the limitations of large institutions to manage fisheries at local scales; (6) recognize the limits of time-series data; and (7) develop better indicators for fishing effort. [ABSTRACT FROM AUTHOR]

There is an urgent need for indicators that anticipate changes in populations of exploited marine species. We modelled the complex patterns of variability found in fisheries time series that are not detected using classical models. We applied fractal analyses to detect time-invariant scaling symmetries in daily catch time series from the smooth pink shrimp (Pandalus jordani) fishery from the west coast of Vancouver Island, British Columbia, Canada. A universal multifractal model, which accounts for intermittent fluctuations and extreme values in a time series, provided a better fit to daily catches than a monofractal model. Multifractality is an indication of multiple scaling patterns and suggests that more than one process is affecting the variability of catches. Fractal dynamics in catch time series were found for a range of scales between 16 and 120 fishing days. To our knowledge, this is the first time that multifractality has been demonstrated for an invertebrate fishery. The multifractal model has the potential to provide an in-season estimate (up to 120 fishing days) of the variability of shrimp catches based on the variability at time scales less than 1 month. Changes in these fractal patterns may provide an early warning that conditions underlying this fishery are changing. Il existe un besoin urgent d'indicateurs qui puissent anticiper les changements demographiques des especes marines exploitees. Nous avons modelise les patrons complexes de variabilite trouves dans les series chronologiques des peches qui ne sont pas deceles par les modeles classiques. Des analyses fractales nous ont servi a detecter des symetries d'echelle invariables dans le temps dans les series chronologiques de prises journalieres dans la peche a la crevette oceanique (Pandalus jordani) sur la cote ouest de l'ile de Vancouver, Colombie-Britannique, Canada. Un modele multifractal universel, qui tient compte des fluctuations intermittentes et des valeurs extremes dans la serie chronologique, fournit un meilleur ajustement aux prises journalieres qu'un modele monofractal. La multifractalite est une indication de la presence de patrons de cadrage multiples et laisse croire qu'il y a plus qu'un processus qui affecte la variabilite des prises. Nous avons trouve une dynamique fractale dans les series chronologiques de prises sur une gamme d'echelles allant de 16 a 120 jours de peche. A notre connaissance, c'est la premiere fois que l'on demontre l'existence de multifractalite dans un peche d'invertebres. Le modele multifractal a le potentiel de fournir au cours de la saison (de jusqu' a 120 jours de peche) des estimations de la variabilite des prises de crevettes basees sur la variabilite a des echelles temporelles de moins d' un mois. Les changements dans ces patrons fractals peuvent fournir un systeme d' alerte indiquant que les conditions sous-jacentes a cette peche sont en train de changer. [Traduit par la Redaction], Introduction Fractal theory has been used in aquatic sciences to quantify scale-invariant relationships under the form of scaling or power laws (Seuront 2010). These scaling laws represent patterns that help [...]

Abstract--Larval development of the sidestriped shrimp (Pandalopsis dispar) is described from larvae reared in the laboratory. The species has five zoeal stages and one postlarval stage. Complete larval morphological characteristics [...]

The effects of climate warming on ecosystem dynamics are widespread throughout the world's oceans. In the Northeast Pacific, large‐scale climate patterns such as the El Niño/Southern Oscillation and Pacific Decadal Oscillation, and recently unprecedented warm ocean conditions from 2014 to 2016, referred to as a marine heatwave (MHW), resulted in large‐scale ecosystem changes. Larval fishes quickly respond to environmental variability and are sensitive indicators of ecosystem change. Categorizing ichthyoplankton dynamics across marine ecosystem in the Northeast Pacific can help elucidate the magnitude of assemblage shifts, and whether responses are synchronous or alternatively governed by local responses to regional oceanographic conditions. We analyzed time‐series data of ichthyoplankton abundances from four ecoregions in the Northeast Pacific ranging from subarctic to subtropical: the Gulf of Alaska (1981–2017), British Columbia (2001–2017), Oregon (1998–2017), and the southern California Current (1981–2017). We assessed the impact of the recent (2014–2016) MHW and how ichthyoplankton assemblages responded to past major climate perturbations since 1981 in these ecosystems. Our results indicate that the MHW caused widespread changes in the ichthyoplankton fauna along the coast of the Northeast Pacific Ocean, but impacts differed between marine ecosystems. For example, abundances for most dominant taxa were at all‐time lows since the beginning of sampling in the Gulf of Alaska and British Columbia, while in Oregon and the southern California Current species richness increased as did abundances of species associated with warmer waters. Lastly, species associated with cold waters also increased in abundances close to shore in southern California during the MHW, a pattern that was distinctly different from previous El Niño events. We also found several large‐scale, synchronized ichthyoplankton assemblage composition shifts during past major climate events. Current climate projections suggest that MHWs will become more intense and thus our findings can help project future changes in larval dynamics, allowing for improved ecosystem management decisions. [ABSTRACT FROM AUTHOR]