Nitrogen (N) and phosphorus (P) losses to surface and coastal waters are still critically high across Europe and globally. Measures to mitigate and reduce these losses are being implemented both at the cultivated land surface and at the edge-of-fields. Woodchip bioreactors represent a new alternative in Denmark for treating agricultural drainage water, and the present study—based on two years of data from five Danish field-bas...

Characterizing the extent of genetic differentiation among individuals and its distribution across the genome is increasingly important to inform both conservation and management of exploited species. The Greenland Halibut is one of the main demersal fish species to be commercially exploited in Eastern Canada, and accurate information on geographic population structure and local adaptation is required to ensure the long-term p...

Inland waters play an active role in the global carbon cycle and emit large volumes of the greenhouse gases (GHGs), methane (CH 4 ) and carbon dioxide (CO 2 ). A considerable body of research has improved emissions estimates from lakes, reservoirs and rivers but recent attention has been drawn to the importance of small, artificial waterbodies as poorly quantified but potentially important emission hotspots. Of particular inte...

In this study, an anadromous strain (L) and a freshwater‐resident (R) strain of brook charr Salvelinus fontinalis as well as their reciprocal hybrids, were reared in a common environment and submitted to swimming tests combined with salinity challenges. The critical swimming speeds ( U crit ) of the different crosses were measured in both fresh ( FW ) and salt water ( SW ) and the variations in several physiological traits (os...

Intraspecific hybridisation may result in hybrid offspring exhibiting superior (heterosis) or inferior (outbreeding depression) fitness relative to their parental populations. As both have been demonstrated in salmonids, consequences of interbreeding between divergent populations are relevant to their conservation. Atlantic salmon Salmo salar L. were extirpated from Lake Ontario by the late 19th Century due to anthropogenic ca...

The influence of salinity on habitat selection and growth in juvenile American eels Anguilla rostrata captured in four rivers across eastern Canada was assessed in controlled experiments in 2011 and 2012. Glass eels were first categorized according to their salinity preferences towards fresh ( FW ), salt ( SW ) or brackish water ( BW ) and the growth rate of each group of elvers was subsequently monitored in controlled FW and...

This study examined the effects of prey exoskeleton characteristics on gastric evacuation patterns in Atlantic cod Gadus morhua . Three distinct stages were highlighted in the gastric evacuation of crustacean prey characterized by a robust exoskeleton. The experiments confirmed that the three shrimp species, Pandalus borealis , Pandalus montagui and Eualus macilentus , and the crab Chionoecetes opilio , were evacuated from the...

This study assessed the paternal effects on the growth of early juvenile winter flounder Pseudopleuronectes americanus and examined the energy allocation strategy employed during this critical stage. Males from three different locations (Passamaquoddy Bay, Baie‐des‐Chaleurs and the St Lawrence Estuary) were crossed with females from the Baie‐des‐Chaleurs, and the growth characteristics of hybrids from settlement to 45 days pos...

Final thermal preferendum ( T ) experiments were conducted in a horizontal thermal gradient tank from the beginning of August 2001 to mid‐November 2001 using Atlantic cod Gadus morhua from 6·5 to 79·0 cm fork length ( L F ). The value of T varied significantly ( P L F ( T = 7·23–0·054 L F ), with smaller (younger) fish choosing higher temperatures than larger (older) fish. The preferendum varied from 6·9° C for fish of 6·5 cm...

The winter flounder is an in‐shore flatfish living in shallow waters on the east coast of North America from Labrador to Georgia. In the St Lawrence estuary, the reproductive season is May and June. Our objective was to test the effects of winter‐spring photoperiod and temperature conditions on the timing of sexual maturation in both males and females. Groups (16 animals each) of winter flounder breeders were maintained from m...

In winter, brook charr Salvelinus fontinalis demonstrated poor osmoregulatory ability. Saltwater (SW) transfer resulted in sharp increases in plasma osmolality and chloride levels, a decrease in white muscle water content and high mortality. A clear improvement of the hypo‐osmoregulatory mechanism e.ciency was observed in spring; by May or June, fish achieved full acclimation within 1 week of SW transfer. In early fall, the ti...