Nipigon Bay Research Articles

Spatial heterogeneity in water quality across the northern nearshore regions of the Laurentian Great Lakes

We provide the first comprehensive analysis of spatial heterogeneity in water quality across the Canadian nearshore regions of the Laurentian Great Lakes (LGL) with periodic sampling in the ice-free seasons from 2000 to 2019 for 24 water quality variables from 52 nearshore sites. We asked: (1) What is the extent, range, and magnitude of spatial heterogeneity in water quality conditions across the nearshore of the Canadian Great Lakes? and (2) How do features of anthropogenic development, sub-basin characteristics, anticipated coastal circulation, and weather influence water quality conditions in the nearshore of the Canadian Great Lakes? Principal Components Analysis explained 42% of the variation in water quality across the Canadian Great Lakes, with high spatial heterogeneity both within and among lakes, ranging from oligotrophic conditions in Lake Superior to eutrophic conditions in Lake Erie. Lakes Erie and Ontario generally had higher concentrations of chloride, chlorophyll a, and nutrients while higher silicate concentrations were observed in Lake Superior. Consistent patterns of degraded water quality were observed in Areas of Concern, such as Hamilton Harbour, Bay of Quinte, Nipigon Bay, and near Thunder Bay. Across the nearshore of the Canadian Great Lakes, regions with warmer air temperatures, in addition to urbanized and agricultural landscapes, were associated with deteriorated water quality. Our study highlights the importance of improving management practices across urban and agricultural landscapes, particularly in consideration of climatic change cumulatively degrading water quality conditions in the highly biologically, culturally, and socioeconomically important nearshore regions of the LGL.

Contemporary genetic structure of walleye (Sander vitreus) reflects a historical inter-basin river diversion

River diversions can have unexpected biological consequences. In the mid-20th century, the upper Ogoki River in northern Ontario was diverted from its original Hudson Bay drainage to flow into the Great Lakes. Although walleye were present in both systems prior to the diversion, the Hudson Bay and Great Lakes watersheds had previously been separated since the early Holocene (7500–8500 years ago). We assessed the effects that this inter-basin diversion has had on the genetic structure of two formerly allopatric populations. We assessed the genetic structure and diversity of walleye in the Ogoki and Little Jackfish river systems and Lake Nipigon (number, distribution, and divergence of identified genetic groups) and quantified the contribution of fish from the historical population (Hudson Bay drainage Ogoki River) and Lake Nipigon to walleye in the Ogoki and Little Jackfish Rivers. Walleye from Ogoki Lake, the Ogoki River diversion through the Little Jackfish River, Lake Nipigon and Nipigon Bay were genotyped at 10 microsatellite loci. Significant genetic differences were detected among sampling locations: walleye from Ogoki Lake, presumably representing fish originally from the historical Ogoki River gene pool, were genetically similar to but statistically distinct from walleye within the diversion. Walleye from sample sites within the diversion and Ombabika Bay appear to form a single genetic group that is largely derived from the Ogoki watershed and differs significantly from walleye in Lake Nipigon and Nipigon Bay. Our findings confirm that the historical river diversion has had long-term effects on the genetic composition of contemporary walleye populations.

Population structure and genomic variation of ecological life history diversity in wild-caught Lake Superior brook trout, Salvelinus fontinalis

Delineating patterns of extant genetic diversity is crucial for understanding the evolutionary history of populations and how they can be conserved. Brook trout (Salvelinus fontinalis; n = 173) were sampled from 11 locations in Nipigon Bay, Lake Superior to evaluate genetic differentiation between migratory (coaster) and non-migratory (resident) individuals. Stable isotope data were used to classify the trophic ecology of individuals, rather than relying on size or capture location and timing to classify ecotypes. Genome-wide association analysis of 4676 single nucleotide polymorphism (SNP) markers was conducted to test if phenotypic and behavioral differences within and among populations of brook trout were linked to allelic variation in the genome. Population genetic structure was also evaluated to determine the source of migratory coasters based on multilocus genotypes from a subset of 906 SNP markers. Significant population genetic structure was revealed among the sampled tributaries, and the population genetic structure suggests that a single, larger stream in the study area, Cypress River, was the primary source of migratory brook trout in Nipigon Bay. There was little evidence of genetic differentiation between sympatric migrant and stream-resident brook trout; across the genome only 11 SNP loci (<1%) were significantly associated with life history type. Our findings suggest that coaster brook trout are an ecotype derived from resident populations, rather than a distinct genetic form. Raw RADseq is deposited in the NCBI Genbank Sequence Read Archive (PRJNA486545). Biological metadata and processed genotypes are found in the Electronic Supplementary Material (ESM).

Tracking Coaster Brook Trout to Their Sources: Combining Telemetry and Genetic Profiles to Determine Source Populations

AbstractRadiotelemetry and genetic analysis are potent tools for informing fisheries management. Although they are usually applied independently, combining them can provide insights on fish origins, movement, and reproduction that could not otherwise be achieved. We applied these two techniques in two separate studies to resolve the origins and habitat use of coaster brook trout Salvelinus fontinalis in Nipigon Bay, Lake Superior. Telemetry of adult fish was used to determine the habitat use of coaster brook trout and microsatellite DNA genotyping to determine the relatedness of coasters to river‐resident brook trout. Both studies indicated that coaster brook trout utilize multiple tributaries within Nipigon Bay for spawning. In terms of philopatric homing, however, the tracking data suggested that coasters show site fidelity between years, whereas the genetic data indicated substantial gene flow among tributaries. For individual tracked fish, the genetic data supported the homing hypothesis for 10 of 11 fish but also conclusively showed straying for 1 individual. The complementary insights from these combined data sets significantly clarify the behavior and habitat use of coaster brook trout and provide an example of the power of these combined methodologies for fisheries management.

Genetic Population Structure among Source Populations for Coaster Brook Trout in Nipigon Bay, Lake Superior

AbstractPopulations of coaster brook trout Salvelinus fontinalis, a potadromous ecotype endemic to Lake Superior, have declined precipitously over the past 150 years. This study quantified the relatedness and genetic structure of remnant coaster and river‐resident brook trout within Nipigon Bay using microsatellite DNA markers. Individual assignment tests confirmed that coaster brook trout are a life history variant of brook trout derived from populations in tributary habitats, rather than a genetically distinct subspecies or evolutionarily significant unit. Furthermore, coasters appear to act as vectors for gene flow among riverine populations, providing genetic connectivity among allopatric tributaries. Molecular data indicated substantial gene flow among several below‐barrier populations, whereas other tributaries contained separate, largely discrete populations. Isolated above‐barrier populations showed the greatest interpopulation differentiation, with limited downstream gene flow observed within tributaries. The relative contributions of the sampled tributary populations to the coasters in Nipigon Bay were highly variable among rivers, indicating that management of source river populations will be critical for the effective conservation and restoration of coaster brook trout within Lake Superior.

Habitat Use and Movement Patterns of Brook Trout in Nipigon Bay, Lake Superior

AbstractBrook trout Salvelinus fontinalis are one of two salmonine species native to Lake Superior. Abundant and widely distributed a century ago, Lake Superior's brook trout (coasters) have been reduced to a few remnant stocks, probably as a result of exploitation and habitat loss. Twenty brook trout captured in Nipigon Bay, Lake Superior, were surgically implanted with radio transmitters and were located from June 1999 to October 2000. Brook trout locations were used to determine the characteristics of utilized lake habitat and to identify streams used for spawning and the spawning areas within them. These locations were also used to establish daily and seasonal movement patterns. A total of 638 locations were obtained during the tracking period, 483 occurring within Nipigon Bay and the remaining 155 within tributaries. Brook trout were located almost exclusively within the shallow nearshore areas of Nipigon Bay; 92% of the locations were less than 7 m deep and 94% were less than 400 m from shore. Brook trout occupied deeper areas with steeper shoreline slopes during July and August, when the water temperatures of shallow nearshore areas were at their highest. Following selected individuals for 24‐h periods revealed that brook trout often used deeper areas during daylight hours and moved to extremely shallow nearshore areas during the night. Radio‐tagged brook trout began ascending tributaries during late summer in both years of this study. The mean residency time for brook trout in tributaries was 46 d. Spawning occurred in early October, and most radio‐tagged brook trout returned to Lake Superior by mid‐October. Four different streams were used during the spawning period. Brook trout entering streams exhibited strong spawning site fidelity between years.

Proterozoic and Archean geology of the Nipigon Embayment: implications for emplacement of the Mesoproterozoic Nipigon diabase sills and mafic to ultramafic intrusions

The Nipigon Embayment is underlain by Archean rocks of the English River, Wabigoon, and Quetico subprovinces, and intruded along the west side by late- to post-tectonic mafic to ultramafic intrusions. The early Mesoproterozoic ultramafic to felsic Badwater intrusion and felsic English Bay Complex are located in the northwest corner of the Nipigon Embayment. Three mafic to ultramafic intrusions, the Disraeli, Seagull, and Hele intrusions, are located south of Lake Nipigon, and the Kitto intrusion is located east of the lake. A number of mafic to ultramafic bodies (Jackfish (Island), Shillabeer, Kama Hill, Nipigon Bay) have only limited outcrops. The gabbroic Nipigon diabase sills intrude all other rocks in the Nipigon Embayment and generally have a consistent mineralogy and geochemistry, except for the Inspiration sill(s) and the McIntyre Sill. Geological and geophysical data suggest emplacement of the ultramafic intrusions by mechanisms similar to those controlling emplacement of the saucer-shaped diabase sills. These mechanisms are partially dependent on a series of pre-existing north-, northwest-, and northeast-trending faults formed prior to Keweenawan magmatism. The presence of sills, rather than dykes, indicates that the Nipigon Embayment was not extensional during the Keweenawan Midcontinent Rift, suggesting that the Nipigon Embayment is not a classic failed arm.

Genetic Assessment of Walleye ( Sander vitreus) Restoration Efforts and Options in Nipigon Bay and Black Bay, Lake Superior

Walleye ( Sander vitreus) stocks in Nipigon Bay and Black Bay historically numbered as the largest stocks in Lake Superior, but collapsed in the 1960s due to overfishing, habitat loss, and other pressures. We used microsatellite DNA analyses to assess the success and relative contributions of past rehabilitation stocking to walleye in Nipigon Bay, and to investigate the relationship between historical and contemporary populations in Black Bay. Based on the genetic data, juvenile stocking and adult transfers from four source populations into Nipigon Bay differed substantially in their contributions to the reestablished population. The genetic data also indicated that natural reproduction was occurring and identified survivors from the former Nipigon Bay population. Similar genetic analysis of scale samples from the historical Black Bay fishery and present-day walleye from a major tributary (Black Sturgeon River) showed that the historical and contemporary samples comprise one genetic stock, which is significantly different from neighboring native and introduced populations. These findings suggest that walleye restoration efforts in Lake Superior are working, and highlight the utility of and options for adaptive management approaches for restoring extirpated populations.

The linkage among ecosystem perturbations, remediation, and the success of the Nipigon Bay fishery

Since the inception of the commercial fishery in Nipigon Bay of Lake Superior, walleye (Stizostedion vitreum) and lake sturgeon (Acipenser fulvescens) have been extirpated and the abundance of lake trout (Salvelinus namaycush), brook trout (Salvelinus fontinalis), and northern pike (Esox lucius) has declined significantly while the abundance of lake whitefish (Coregonus clupeaformis ) and lake herring (Coregonus artedii) has increased. Systemic stresses including eutrophication, airborne contribution of contaminants, and exploitation (reduced by closure of the commercial fishery in 1988) remain but may not impair populations of lake whitefish and herring, which interact less with tributaries and nearshore waters. Improvements in habitat, through water flow management in the Nipigon River, removal of logs in the nearshore, shoreline and stream restoration, cessation of log drives, as well as artificially increasing adult abundance have resulted in resumption of some limited reproduction by walleye and increased egg deposition and early life survival by brook trout. Multiple stresses are still ubiquitous in the Nipigon ecosystem, but relief of several stresses in tributaries and nearshore environments at least appears to have resulted in an initially encouraging response by two species dependent upon these areas.

The linkage among ecosystem perturbations, remediation, and the success of the Nipigon Bay fishery

The linkage among ecosystem perturbations, remediation, and the success of the Nipigon Bay fishery

Paleomagnetic dating of late glacial and postglacial sediments in Lake Superior

The oldest unit of the late Quaternary sedimentary sequence of Lake Superior consists of glacial till that was deposited about 9900 years BP during the last glacial readvance into the Lake Superior basin. The till deposits are unconformably overlain by a thin sequence of bedded sands and silts, which are overlain by a thick sequence of varved sediments (&gt; 10 m in thickness), which in turn are overlain by postglacial silty clays.Unfortunately, 14C has not been found to be a useful tool in dating the late glacial and postglacial sediments of Lake Superior. However, paleodeclination and paleoinclination logs provide a useful method of correlating and indirectly dating cores taken of the late glacial and postglacial sediments. It is concluded from paleomagnetic dating that rhythmic sedimentation ceased before 9200 years BP in the southeastern lake proper and at about 8700 years BP in the southeastern bay areas. However, rhythmic sedimentation continued until about 8200 years BP in the northern part of Lake Superior and until about 8000 years BP in the Nipigon Bay area.

THE FIRST RECORDS OF DOLOMEDES STRIATUS GIEBEL IN ALBERTA AND SASKATCHEWAN (ARANEIDA: PISAURIDAE)

During the summer of 1985, an intensive effort was made to collect the invertebrates, particularly insects and spiders, of the Wagner Natural Area. This is a 162-ha area 6 km west of the city limits of Edmonton, Alta., on the south side of Highway 16X.An examination of the spiders collected in the pitfall pans revealed two species of pisaurids, Dolomedes striatus Giebel, 1869, and Dolomedes triton (Walckenaer, 1837). This is the first record of Dolomedes striatus for Alberta. The previous known western limit of its distribution was more or less between Lake Nipigon and Thunder Bay, Ont. (Carico 1973).

The use of paleomagnetic curves for chrono-stratigraphic correlation of late Quaternary fluvial, estuarine and lacustrine stratigraphic sequences in Nipigon Bay, Lake Superior, Ontario, Canada

A study was carried out In Nipigon Bay, Lake Superior, to evaluate the use of paleomagnetic curves in correlating late Quaternary stratigraphic sequences from a variety of sedimentary environments within a limited geographic area. Oscillations of the paleodeclination and paleoinclination curves result from secular variations of the earth's magnetic field with time, so any correlation horizons picked on the character of either of these curves could be used for chrono-stratigraphic correlation from one core to another within Nipigon Bay. High-resolution paleodeclination and paleoinclination curves were compiled for cores taken from six fluvial, estuarine and lacustrine sites. Both the paleodeclination and the paleoinclination curves show marginal correlation for cores taken from within a specific sedimentary environment and reasonable correlation for cores taken from different sedimentary environments. Paleomagnetic curves can be used for chrono-stratigraphic correlation and in addition show considerable promise as a method for absolute age dating of late Quaternary stratigraphic sequences.

Sedimentation rates in Western Nipigon Bay, Lake Superior using the 210Pb method

210Pb, 226Ra and 137Cs profiles have been measured for sediment cores from three locations in western Nipigon Bay, Lake Superior, Canada. Compaction of the sediment with depth of burial was taken into account in calculating recent sedimentation rates and age profiles at these locations from the excess 210Pb profiles. The rates at two of the locations were 0.85±0.03 mmy −1 (16.7 mg cm −2 y −1) and 1.39±0.12 mmy −1 (29.5 mg cm −2 y −1). The third core had an anomaly in the 210Pb profile below a depth of 3.5 cm corresponding to the time that the outfall of a nearby pulp mill was relocated. The 137Cs profiles of the two undisturbed cores were in accord with the corresponding age/depth curves derived from the 210Pb measurements.

Influence of a pulp and paper mill effluent on aspects of distribution, survival and feeding of Nipigon Bay, Lake Superior, larval fish.

Surface distribution of Nipigon Bay larval fish was characterized by high abundance, between 500 and 2100 larval fish/10,000 m3 near shore, particularly in proximity to the pulp and paper mill effluent discharge, and low abundance, less than 100/10,000 m3 away from shore. Static bioassay indicated that approximately 60% effluent concentration was intolerable to the natural mixed larval fish community. No wood fibre was found among stomach contents and no difference was apparent in stomach contents of fish caught in influenced and uninfluenced areas. Data therefore suggest that larval fish either were not greatly influenced by plume conditions or were transients.

Walleye (Stizostedion vitreum vitreum) Fluctuations in the Great Lakes and Possible Causes, 1800–1975

Changes in walleye (Stizostedion vitreum vitreum) stocks in the Great Lakes from 1800 to 1975 were linked to proliferation of foreign species of fish and culturally induced sources of stress — exploitation, nutrient loading, alteration of spawning habitat, and toxic materials. During the 1800s, three small spawning stocks (and probably many others) were damaged or destroyed because of either overfishing or elimination of spawning habitat through logging, pollution, or damming.During 1900–40, stocks in the Michigan waters of Lake Superior, southern Green Bay, the Thunder Bay River of Lake Huron, the North Channel of Lake Huron, and the New York waters of Lake Ontario declined gradually. Pollution, in general, and degradation of spawning habitat, in particular, probably caused three of the declines and overexploitation was suspected in two instances. In addition, the decline of three of these stocks occurred when rainbow smelt (Osmerus mordax) were increasing.During 1940–75, stocks in seven areas declined abruptly: Saginaw Bay (1944), northern Green Bay (1953), Muskegon River (mid-1950s), western Lake Erie (1955), Nipigon Bay (late 1950s), Bay of Quinte (1960), and Black Bay (mid-1960s). The decline of each stock was associated with a series of weak year-classes. The stocks were exposed to various sources of stress, including overexploitation, pollution, and interaction with foreign species, which, if not important in the decline, may be suppressing recovery. Only the western Lake Erie stock recovered, in part due to a reduction in exploitation and, possibly, because of the relatively low density of smelt and alewives (Alosa pseudoharengus) in the nursery areas.Relatively stable stocks persisted in five areas: Wisconsin waters of Lake Superior, Lake St. Clair — southern Lake Huron, eastern Lake Erie, northern Lake Huron, and parts of Georgian Bay. Pollution problems were relatively minor in these areas and exploitation was light during recent decades. Apparently these stocks were more capable of withstanding the additional stresses exerted by alien species. Key words: population fluctuations, Percidae, Stizostedion, Great Lakes walleye, history of fisheries, summary of stresses, harvests, management implications

Relation between Nipigon Bay Benthic Macroinvertebrates and Selected Aspects of Their Habitat

In areas of Nipigon Bay unaffected by pulp and paper mill effluent, the benthic macroinvertebrate community was characterized by low standing stocks and high diversity. The coefficient of community and percentage similarity of community defined two major environments in Nipigon Bay, generally related to distance from the mill outfall. Near the pulp and paper mill outfall, further zonation of the benthic macroinvertebrate community was apparent. Inhibition and ultimate extinction of oligochaete populations appeared related to increasing levels of organic carbon and total sulphur, both associated with proximity to the outfall. Since a 10-yr period following abatement measures has not resulted in major responses by the macroinvertebrate community, recovery is expected to be slow.

Organic Contaminant Residues in Fishes from Nipigon Bay, Lake Superior

Three species of fish, caught at various distances from a kraft pulp and paper mill effluent discharge in Nipigon Bay, were analyzed for organic contaminants. Fishes from all sites contained residues of polychlorinated biphenyls and DDE. Most samples were also contaminated with hexachlorobenzene and several samples contained phthalic acid esters.From sampling sites close to the mill discharge, dehydroabietic acid was observed in one extract of each of the three fish species investigated. Two isomers of tetrachlorobenzene and one trichlorobenzene isomer were identified in a longnose sucker (Catostomus catostomus) extract from the vicinity of the mill outfall.

Distribution of Some Organic Compounds in the Receiving Waters of a Kraft Pulp and Paper Mill

Water, seston, sediment, and macrophyte samples were collected from Nipigon Bay, Lake Superior at distances up to 6.8 km from the effluent discharge of a kraft pulp and paper mill at Red Rock, Ontario. Fifteen compounds have been identified in mill effluent and six of these were found in samples from the Bay. Mill-related compounds were found most often in water and sediment samples, less often in seston samples, and in none of the macrophytes samples. Dehydroabietic acid, present in mill effluent in excess of 1 mg/ℓ, was found in most water and sediment samples and a few seston samples. This compound is a good indicator of the areal influence of the effluent. Palmitic acid and dioctyl phthalate were also widely distributed. Acetovanillone and sandaracopimaric acid were found in one water sample 1.0 km from the discharge. 7-oxodehydroabietic acid was found in five water samples at distances of up to 4.7 km from the discharge. This is apparently the first time that this compound has been reported in a mill effluent or in environmental samples.

Analysis of a Pulp and Paper Mill Effluent Plume

Several chemical surveys of a pulp and paper mill effluent plume in Nipigon Bay, Lake Superior, are analyzed to determine the average area and volume contained by a range of isoconcentration boundaries. Sodium, dissolved organic carbon, particulate organic carbon, and particulate organic nitrogen are the chemical variables used to examine changes occurring in the plume. Data are analyzed from three sampling regimes: (1) dye-slug tracking which allows interpretation of time-related processes, (2) surface surveys which indicate the areal extent of the plume, and (3) vertical profile surveys which indicate the degree of depth penetration for effluent components.Dilution dominates in the plume, though the nonconservative substances undergo significant changes. The plume area enclosed in a contour of 1% effluent is approximately 1.5 km2. Mass balance calculations indicate exchanges occurring between the plume and the old fiber beds in the vicinity of the effluent outfall.