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Atlantic herring (Clupea harengus) are economically and ecologically significant but have been in decline in Atlantic Canada due to an uncertain combination of environmental recruitment controls, predation, and fishing (commercial fishery and poorly documented bait removals). Fisheries and Oceans Canada partially closed Atlantic mackerel (Scomber scombrus) and herring fisheries in March 2022 amid controversy and disagreement. Here, we develop a conceptual model for natural and anthropogenic controls on herring abundance centered on the southern Gulf of St. Lawrence (sGSL) and evaluate the likely importance of each. We provide the first estimates of the magnitude of bait fishery withdrawals in the sGSL. The decline in sGSL herring is likely driven by natural predation exacerbated by fishing. Bait fishery removals were 182 tonnes in 2021, suggesting that previous estimates for removals of spring-spawning herring were ~30% too low. Fisheries closure is consistent with a precautionary approach given uncertainties and irreversibility of stock collapse. Ecosystemic models are needed but will be difficult to develop given the incomplete understanding of prey substitutability and net effect of interacting environmental processes. Key words: Atlantic herring, bait fishery, fishery rebuilding, fishery closure, environmental modelling, precautionary principle, 1. Introduction Forage fish fulfil large economic, environmental, and social roles worldwide; commercial landings of forage fish have been valued at $5.6 billion per year globally, with landings of species [...]

Simple nutritional condition indicators are needed to provide information on the influence of ecosystem changes on the populations of the American lobster Homarus americanus (H. Milne Edwards, 1837) on various timescales. This study validates the use of the water content (% wet mass) of the digestive gland as an indicator of nutritional condition in the lobster (carapace length 65–127 mm) by assessing its capacity to estimate digestive-gland lipid reserves under variable environmental and physiological conditions. The validation was completed using samples from wild lobsters dissected shortly after being captured during different seasons and in various locations in the St. Lawrence Estuary and Gulf of St. Lawrence (GSL), and data from an environmentally realistic laboratory study on post-ovigerous females from the southern and the northern GSL sampled at different stages of their molt cycle. In both wild and experimental lobsters, water content was the best predictor of lipid reserves compared to other condition indicators (i.e. condition factor, various digestive-gland indices, and hemolymph Brix index). A strong linear relationship was found between lipid and water contents. Lipid content and interrelated molting status were identified as two important factors leading to the variations in water-fat regression equations among groups of wild or experimental lobsters. As lipid content could vary spatiotemporally in unexpected ways in a changing environment, it is recommended to use a sampling event-specific regression line to estimate digestive-gland lipid content from measured water content in field monitoring programs. Combining water content with molt status indicators such as Brix index is recommended to support interpretation of the observed variations in condition. [ABSTRACT FROM AUTHOR]

Abstract: We have developed an approach to restore bogs after peat extraction, but, when sedge-peat layers are exposed, the minerotrophic remnant peat conditions require restoration towards a fen ecosystem. Three [...]

To the American lobster (Homarus americanus) fishery in the Northeast US and Atlantic Canada, 2012 may have gone down as the year that drove climate change home. An ocean heat [...]

The article examines the structure of fisheries governance in Canada with a specific focus on Nunavut and the co-management framework, created through the Nunavut Land Claims Agreement (NLCA). Topics discussed include existing legal framework governing the harvesting of wildlife resources in Nunavut and provides a brief overview of knowledge systems; and existing legal framework governing the harvesting of wildlife resources in Nunavut and provides a brief overview of knowledge systems.