USGS Science⌕ Search

USGS · 70250108

A comparison of stable isotopes and polychlorinated biphenyls 1 among genetic strains of Lake Ontario lake trout (Salvelinus namaycush)

Abstract

This study quantified stable carbon (δ 13 C) and nitrogen (δ 15 N) isotopes, polychlorinated biphenyl (PCB) concentrations and growth rates among multiple genetic strains of Lake Ontario lake trout ( Salvelinus namaycush ) to evaluate the potential role of genetics in these parameters. Fish ranging in age from 1 to 31 years ( n = 72) and representing nine genetic strains including wild-recruits to hatchery fish derived from Lakes Ontario, Superior and Champlain watersheds, and individuals of unknown hatchery origin. Carbon (δ 13 C) and nitrogen (δ 15 N) stable isotope values averaged −22.2 ‰ and 17.4 ‰, respectively, but did not differ significantly among genetic strains. ΣPCB concentrations ranged from 42 to 1820 ng/g and varied significantly among individuals including those of similar age and genetic strain. For example, Sum PCB (ΣPCB) concentrations among 7-year-old fish ( n = 16) ranged from 159 to 607 ng/g, which compares to growth rates of 3.5 – 32.9 %/yr for these same fish. Multivariate analysis of stable isotope and PCB profiles, however, provided considerable resolution among the strains. For example, fish of unknown hatchery origin ordinated most similar to Seneca Lake fish, the predominant strain stocked in Lake Ontario. Wild fish had a unique ordination with only Lake Superior Klondike strain fish overlapping into their ordination space. Lakes Champlain and Superior strain individuals had similar ordinations but did not overlap substantially with wild or Klondike strain fish. Combined, these differences agree with the ecologies described for these strains in their native ecosystems suggesting that insight can be gained from strain specific evaluations of ecological tracers and these pollutants among Great Lakes lake trout.

Explore related subjects

90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 43.232649116660866° to 43.6042153418901° latitude; -78.57910303634092° to -76.76283308220034° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Nicole E. Saavedra, N. Roxanna Razavi, Donald J. Stewart, Brian F. Lantry, Gordon Paterson. 2024. A comparison of stable isotopes and polychlorinated biphenyls 1 among genetic strains of Lake Ontario lake trout (Salvelinus namaycush). https://doi.org/10.1016/j.jglr.2023.102252

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Groundwater nutrient contributions to surface water in the upper Maumee River basin

Harmful algal blooms triggered by nutrient loading have negatively affected Lake Erie water quality for decades, but the role groundwater plays in transporting nutrients to tributary streams is unclear. Here, we apply a multi-scale approach to investigate groundwater nitrogen (N) and phosphorus (P) dynamics at the field scale, along a groundwater flow path, and at the Maumee River basin scale. Unsaturated zone monitoring indicates that macropore flow is the primary mechanism for N and P leaching with nitrate and orthophosphate (OP) concentrations from macropore samplers more than double those from soil-matrix samplers. Shallow (< 4.5 m) groundwater nitrate concentrations indicate the timing of saturated-zone nitrate fluxes is crop dependent with more nitrate mobilized during the maize growing season whereas concentrations below soybeans can remain elevated (> 3 mg/L) through winter months. A three-end-member hydrograph analysis for the upper Maumee River basin indicates that tile drains transport most subsurface N and P with greater than 15,000 kg per day of nitrate transported between January and May. Orthophosphate concentrations in tile drainage at an edge-of-field site correlate well with concentrations in a nearby tributary of the Maumee River. While runoff is the dominant source of OP loading, tile drainage and groundwater discharge contributed an estimated 36% of OP load during a 2018–2022 analysis period with most subsurface loading occurring between January and March. These findings highlight how best management practices (such as cover crops and tile drainage control structures) can be used to help limit leaching and tile effluent during the nongrowing season.

Indiana↗

Low recapture rates preclude survival estimates of larval and juvenile sea lamprey in the Lake Erie basin

Our goal was to estimate survival of non-native larval and juvenile sea lamprey ( Petromyzon marinus ) in the Lake Erie basin and compare estimates with those from Lakes Huron and Michigan. Accomplishing the goal would inform decisions about allocating limited control resources among the Laurentian Great Lakes to protect valued fish stocks. Between 2012 and 2018, coded-wire tagged (CWT) larvae and juveniles were released in three Lake Erie tributaries where they were unlikely to experience control program-induced mortality. Adult sea lamprey returning to tributaries to spawn were captured and scanned for CWTs, with the objectives being to determine (1) if survival differed between the Saint Clair River and other sea lamprey-producing tributaries of Lake Erie, and (2) if survival in Lake Erie differed from estimates in Lakes Huron and Michigan. No tagged larvae were recaptured as adults, preventing survival estimation. Recovery probability of tagged juveniles released in the Saint Clair River in the adult stage was about half that of other streams, but statistical comparisons were limited due to low recovery (Objective 1). Estimated lake-wide adult sea lamprey abundance was at record lows when tagged larvae were expected to return as adults. Simulations suggest that survival estimates of larval and juvenile sea lamprey in Lake Erie may be less than survival estimated in Lakes Huron and Michigan (Objective 2). Understanding survival rates of sea lamprey across the Great Lakes and individual streams could guide control effort allocation, although alternative methods for quantifying survival may be needed given the challenges encountered here.

Lake Erie basin↗

Short-term outcomes of juvenile sea lamprey feeding on lake trout vary among parasite–host number combinations in a controlled laboratory setting

The parasitic juvenile stage of the invasive sea lamprey ( Petromyzon marinus ) causes host injury and mortality in the Laurentian Great Lakes, yet laboratory feeding studies have generally used single-host or simple host-choice designs. We conducted controlled 7-d trials to quantify lake trout ( Salvelinus namaycush ) wounding, sea lamprey recovery, positive net mass change, growth, and wound location across four lamprey–host number combinations: 1:3, 6:6, 6:3, and 18:9. Candidate models evaluated whether outcomes were better explained by number combination, lamprey abundance, lamprey:host ratio, or separate lamprey and host effects. Across 27 trials, 70 of 135 lake trout (51.9%) were wounded, producing 113 wounds. Wounding was lowest in 1:3 (sea lamprey:host) and highest in 18:9, where 72.2% of hosts were wounded, and wound intensity was 1.33 wounds per host. In pooled descriptive models, each additional stocked sea lamprey was associated with a 13% increase in the odds that an exposed lake trout was wounded and an 8.3% increase in wound intensity per host. Among 173 recovered sea lamprey, 104 (60.1%) exhibited positive net mass change. This probability varied among number combinations, whereas candidate predictors provided little improvement over constant-mean models for continuous growth. Among lamprey exhibiting positive net mass change, intercept-only models were best supported, indicating little evidence that growth magnitude varied systematically among combinations. Wounds were distributed non-randomly among host body regions relative to proportional surface area. Short-term outcomes, therefore, varied among the tested parasite–host number combinations.

Journal of Great Lakes Research↗