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Understanding the drivers behind fluctuations in fish populations remains a key objective in fishery science. Our predictive capacity to explain these fluctuations is still relatively low, due to the amalgam of interacting bottom-up and top-down factors, which vary across time and space among and within populations. Gaining a mechanistic understanding of these recruitment drivers requires a holistic approach, combining field, experimental and modelling efforts. Here, we use the Western Baltic Spring-Spawning (WBSS) herring (Clupea harengus) to exemplify the power of this holistic approach and the high complexity of the recruitment drivers (and their interactions). Since the early 2000s, low recruitment levels have promoted intense research on this stock. Our literature synthesis suggests that the major drivers are habitat compression of the spawning beds (due to eutrophication and coastal modification mainly) and warming, which indirectly leads to changes in spawning phenology, prey abundance and predation pressure. Other factors include increased intensity of extreme climate events and new predators in the system. Four main knowledge gaps were identified related to life-cycle migration and habitat use, population structure and demographics, life-stage specific impact of multi-stressors, and predator–prey interactions. Specific research topics within these areas are proposed, as well as the priority to support a sustainable management of the stock. Given that the Baltic Sea is severely impacted by warming, eutrophication and altered precipitation, WBSS herring could be a harbinger of potential effects of changing environmental drivers to the recruitment of small pelagic fishes in other coastal areas in the world. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1007/s11160-022-09739-2. B Correction to: Rev Fish Biol Fisheries b https://doi.org/10.1007/s11160-022-09739-2 Following publication of the original article [1], the authors identified an error in Table 1. [Extracted from the article]

During development crustaceans experience a range of oxygen tensions (PO) in their various developmental environments. Therefore, it is likely that they developed varying strategies to respond to hypoxic events during their ontogeny. We investigated short-term responses to various oxygen levels in early life stages of two anomuran decapods Petrolisthes laevigatus and Lithodes santolla that develop in different habitats. Embryos and juveniles of P. laevigatus inhabit the upper rocky intertidal and are regularly exposed to hypoxia during low tide, while larvae of this species inhabit well-oxygenated surface waters. L. santolla is a subtidal species that inhabits fjords and is frequently exposed to hypoxia due to stratification in this environment. Oxygen consumption (MO), lactate content, RNA/DNA ratio, lactate dehydrogenase and superoxide dismutase (SOD) activities were measured in embryos, larvae and juveniles after exposure to POs of 3-21 kPa for 24 h. Results indicated considerable variation in hypoxia tolerances among the ontogenetic stages of both species. Embryos of both species relied on anaerobiosis at all tested PO yet were able to regulate MO until 15 kPa. In contrast, larvae of L. santolla were oxyconformers, while those of P. laevigatus continued to oxyregulate in conjunction with a decrease in SOD activities in response to low PO. Juveniles of P. laevigatus were more sensitive to hypoxia than those of L. santolla as all tested parameters were affected at higher PO in the former. This study shows that aerobic and anaerobic metabolism, antioxidant defence and protein synthesis of early life stages are diverse and reflect the variety of inhabited environments. [ABSTRACT FROM AUTHOR]