Nikolaus Gantner

University of Northern British Columbia · Environmental Science Program

Lake trout, Salvelinus namaycush, are considered a freshwater species but have been documented using brackish and marine water environments in the Arctic in a semi-anadromous manner. The objective of this study was to describe lake trout life histories present in the brackish waters of Husky Lakes, Northwest Territories (NT) using otolith strontium...

On 4 August 2014, a catastrophic breach of the Mount Polley mine tailings impoundment released ~25 M m3 of tailings and water and scoured an unknown quantity of overburden into the West Basin of Quesnel Lake. We document Quesnel Lake and Quesnel River observations for 2 months postspill. Breach inflows raised Quesnel Lake by 7.7 cm, equivalent to ~...

Biotic and abiotic fractionation of mercury (Hg) isotopes has recently been shown to occur in aquatic environments. We determined isotope ratios (IRs) of Hg in food webs (zooplankton, chironomids, Arctic char) and sediments of 10 Arctic lakes from four regions and investigated the extent of Hg isotope fractionation. Hg IRs were analyzed by multicol...

Bull trout ( Salvelinus confluentus ) research has historically focused on highly impacted systems or occurred in a reactionary manner following overharvest. Here, we used telemetry and multi‐state capture–recapture modelling to inform management decision‐making for this highly migratory, conservation‐listed species in British Columbia's upper Fras...

Age, growth and diet of small (<100 mm fork length) Arctic charr, Salvelinus alpinus, from Lake Hazen, Ellesmere Island, Canada were studied during the ice-free season. Small charr (n=105) were captured by electro-fishing in the near-shore area of the lake (<1 m) during the first two weeks of August, 2001. Fish were measured (fork length, nearest 0...

Non‐anadromous forms of Arctic char (Salvelinus alpinus), those that are restricted to lakes and rivers, typically have higher mercury concentrations than anadromous forms that migrate to and from the sea. Using tissue burden data from the literature and our own analyses, we performed a screening‐level risk assessment of methylmercury for non‐anadr...

Following the Fukushima nuclear disaster in 2011, agencies began monitoring waters of coastal B.C. for radiation contamination. While radiation associated with the disaster has been detected, levels determined to date are far below those considered harmful to human or marine health.

Despite the many studies that have shown minimal health risks to individuals living outside of Japan following the Fukushima Nuclear Accident, there are persisting concerns regarding the consumption of Pacific seafood that may be contaminated with radioactive species from Fukushima. To address these concerns, the activity concentrations of anthropo...

Conference poster

The Canadian Arctic has vast freshwater resources, and fish are important in the diet of many Northerners. Mercury is a contaminant of concern because of its potential toxicity and elevated bioaccumulation in some fish populations. Over the last decade, significant advances have been made in characterizing the cycling and fate of mercury in these f...

Fish mercury (Hg) concentrations have been measured over the last 30–40 years in all regions of Canada as part of various monitoring and research programs. Despite this large amount of data, only regional assessments of fish Hg trends and patterns have previously been attempted. The objective of this study was to assemble available freshwater fish...

Pingualuk Lake fills a deep crater in the Parc National des Pingualuit on the Ungava Peninsula (Nunavik, Canada) and is isolated from nearby surface waters. The main objectives of this study were to determine and compare the concentrations of two atmospherically derived contaminants, mercury and perfluorinated chemicals (PFCs), in the lake water co...

Arctic lakes can provide a long-term perspective on environmental change, including trends in long-range atmospheric transport and deposition of contaminants, inferred from studies of sediment cores. In this study, we conducted the first detailed bathymetric survey of Lake Hazen (Quttinirpaaq National Park, Ellesmere Island, Nunavut), the world's l...

Environmental contextMercury, in its methylated form, is a neurotoxin that biomagnifies in marine and terrestrial foodwebs leading to elevated levels in fish and fish-eating mammals worldwide, including at numerous Arctic locations. Elevated mercury concentrations in Arctic country foods present a significant exposure risk to Arctic people. We pres...

The Canadian Arctic contains vast freshwater resources that cover about 140,000 km 2 of land north of 60° latitude (Prowse et al. 2009). Freshwater fish are important in the diet of many Northerners, particularly in the Northwest Territories, Yukon, and northern Quebec. Over the last two decades, extensive monitoring of Hg in freshwater fish has be...

A statistically robust method was applied to 83 time-series of mercury in Arctic biota from marine, freshwater and terrestrial ecosystems with the purpose of generating a 'meta-analysis' of temporal trend data collected over the past two to three decades, mostly under the auspices of the Arctic Monitoring and Assessment Program (AMAP). Sampling loc...

Mercury concentrations ([Hg]) in Arctic food fish often exceed guidelines for human subsistence consumption. Previous research on two food fish species, Arctic char (Salvelinus alpinus) and lake trout (Salvelinus namaycush), indicates that anadromous fish have lower [Hg] than nonanadromous fish, but there have been no intraregional comparisons. Als...

Canada agreed in 2008 to act as the lead country for the initial development of the Freshwater Expert Monitoring Group (FEMG) of CAFF’S Circumpolar Biodiversity Monitoring Program (CBMP). Prior to the first meeting of the FEMG Steering Group in May 2010, Canadian experts developed this document to provide a framework for the FEMG. “Development of a...

Mercury concentrations ([Hg]) in Arctic food fish often exceed guidelines for human subsistence consumption. Previous research on two food fish species, Arctic char (Salvelinus alpinus) and lake trout (Salvelinus namaycush), indicates that anadromous fish have lower [Hg] than nonanadromous fish, but there have been no intraregional comparisons. Als...

Concentrations of mercury (Hg) have increased slowly in landlocked Arctic char over a 10- to 15-year period in the Arctic. Fluxes of Hg to sediments also show increases in most Arctic lakes. Correlation of Hg with trophic level (TL) was used to investigate and compare biomagnification of Hg in food webs from lakes in the Canadian Arctic sampled fro...

Among-lake variation in mercury (Hg) concentrations in landlocked Arctic char was examined in 27 char populations from remote lakes across the Canadian Arctic. A total of 520 landlocked Arctic char were collected from 27 lakes, as well as sediments and surface water from a subset of lakes in 1999, 2002, and 2005 to 2007. Size, length, age, and trop...

Concentrations of mercury (Hg) have increased slowly in landlocked Arctic char over a 10- to 15-year period in the Arctic. Fluxes of Hg to sediments also show increases in most Arctic lakes. Correlation of Hg with trophic level (TL) was used to investigate and compare biomagnification of Hg in food webs from lakes in the Canadian Arctic sampled fro...

Selected chemical data collected between 2001 and 2008 from lakes and streams in Quttinirpaaq National Park, Nunavut are tabulated.

Human health risk assessment of dietary mercury (Hg) exposure in Canada assumes that all Hg from fish consumption is in the form of methylmercury (MeHg), the more bioavailable and hazardous form of Hg. In contrast, the risk assessment of dietary Hg to Inuit in northern Canada assumes that no more than two-thirds of dietary Hg is MeHg since mammal o...

Arctic char (Salvelinus alpinus L.), the top predator in High Arctic lakes, often is used as a bioindicator of Hg contamination in Arctic aquatic ecosystems. The present study investigated effects of trophic position, size, and age of Arctic char in Lake Hazen, the largest lake in the Canadian High Arctic (81 degrees 50'N, 70 degrees 25'W), on Hg b...

Wrasses (Perciformes, Labridae) are common littoral fishes in the Mediterranean Sea. We studied gut content, feeding morphology, feeding behavior, as well as diurnal activity of four abundant labrid species near Calvi, Corse. The studied species, Coris julis, Labrus merula, Sym-phodus tinca, and Symphodus roissali, are diurnal species, found in an...