A seasonal comparison of trace metal concentrations in the tissues of Arctic charr (Salvelinus alpinus) in Northern Québec, Canada

Abstract

Ecotoxicological research detailing trace metal contamination and seasonal variation in the tissues of northern fishes such as Arctic charr (Salvelinus alpinus) has been poorly represented in the literature beyond examination of mercury. In an effort to address this, anadromous Arctic charr were collected from the Deception River watershed in the late summer and post-winter season, before quantifying seasonal and organotropic variations in dorsal muscle and liver concentrations of arsenic, cadmium, chromium, copper, nickel, lead, and zinc. Potential linkages with biological variables (fork length, age, and somatic condition) and indicators of feeding behaviour (δ 13 C and δ 15 N) were also assessed. Trace metal organotropism favouring elevation in liver tissue concentrations was exhibited by cadmium, copper, nickel and zinc, while arsenic, chromium and lead exhibited no significant organotropic variation. Seasonal differences in concentrations were metal and tissue dependent, but generally increased in tissues collected from post-winter sampled Arctic charr. Significant correlations with biological and trophic descriptors were also determined to be element and tissue dependent. These parameters, in addition to season, were incorporated into multi-predictor variable models, where variations in trace metal concentration data were often best explained when season, somatic condition, and trophic descriptors were included. These variables were also of greatest relative importance across all considered trace metals and tissue types. These findings suggest that seasonally linked processes have the greatest influence on trace metal concentrations in anadromous Arctic charr. Future metal-related research on Arctic charr and other northern fish species should further consider these variables when evaluating elemental accumulation.

Exploring the role of water chemistry on metal accumulation in biofilms from streams in mining areas

“…The biomonitoring approach has proven to be very useful as a proxy for the bioavailability of metals in the field. In recent years, many biological models have been used in natural waters, such as fish (Weber et al, 2008;Martyniuk et al, 2020), invertebrates (Lebrun et al, 2015;Mebane et al, 2020) or freshwater periphytic biofilms (Xie et al, 2010;Faburé et al, 2015). The latter are particularly useful for a biomonitoring approach in natural waters; they are sedentary, ubiquitous and at the base of the trophic chain.…”

Evidence of a temperature–oxygen squeeze within floodplain thermal refuge habitats

“…While this could suggest that the epilimnetic temperatures we observed were not suboptimally warm, temperatures that maximise aerobic scope may not maximise fitness (Holt & Jørgensen, 2015). The optimal temperature for growth depends on foraging rates (Brett, 1971); fish consuming low rations for prolonged periods will often select for cooler temperatures (Javaid & Anderson, 1967; Martyniuk et al., 2020). In our system, cutthroat trout in floodplain alcoves frequently subsist on small rations comprised of relatively low‐quality prey (i.e.…”