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At least 415 records · Page 23Linked to original sources
USGS2024

Synchrony of alewife, Alosa pseudoharengus, year-class strength in the Great Lakes region

Fish recruitment is interannually variable and challenging to predict. Annual recruitment is often regionally synchronized among populations and identifying drivers of such synchrony may help shed light on recruitment dynamics. We investigated interannual variation of alewife Alosa pseudoharengus recruitment by estimating year-class strength for populations from three of the Laurentian Great Lakes (lakes Huron, Michigan, and Ontario) using annual assessment survey data from 1968 to 2022. We first determined the age when year-class strength was set for each dataset. We then used a mixed-modeling approach incorporating age, year-class, and sampling year to estimate year-class strength for each study lake. Thereafter, we evaluated regional synchrony in year-class strength across the three lakes and evaluated potential climatic drivers of synchrony. Our results suggest that alewife year-class strength is set by age-1. Our model-derived indices of alewife year-class strength were synchronized among the three lakes, and we identified spring-summer degree-days as a potential regional driver of synchrony. This analysis highlights the potential for strong influence of climatic conditions on fish recruitment in large freshwater systems.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2024

Declines and shifts in morphological diversity of ciscoes (Coregonus spp.) in lakes Huron and Michigan, 1917–2019

Ciscoes ( Coregonus spp . ) were historically abundant and ecologically important in Laurentian Great Lakes ecosystems. Despite well-documented declines in their abundance and taxonomic diversity, declines in morphological diversity remain understudied. This knowledge gap is especially pertinent for lakes Michigan and Huron, which have each lost six of eight historical species. Improved understanding of historical and contemporary morphological diversity of Great Lakes ciscoes can inform ongoing restoration efforts and further elucidate the factors that contributed to declines. Our goal was to characterize shifts in morphological diversity of ciscoes in lakes Michigan and Huron over a century (1917–2019). We analyzed size-corrected morphometric and meristic measurements from three periods: Early (1917–1923), Middle (1950–1972), and Contemporary (2015–2019). We then identified morphologically distinct clusters while remaining agnostic to species identifications. We found that morphological diversity and the number of distinct clusters declined over time. We then leveraged species identifications to highlight key species losses and examine morphological shifts among extant species. Our findings provide insights into the historical and contemporary morphological diversity of ciscoes and will inform restoration efforts.

Lake Huron, Lake Michigan↗
USGS2025

Dispersal and survival of sea lamprey in Lake Erie and connected waterways

Invasive sea lamprey inhabiting the North American Laurentian Great Lakes are the target of the world’s longest running vertebrate invasive species control program. However, metapopulation dynamics comprising survival and dispersal during the sea lampreys’ lake-resident life stages are poorly understood. We applied acoustic telemetry and continuous-time multistate capture-recapture modeling to address this knowledge gap in Lake Erie. We acoustic-tagged sea lamprey (n = 619) and deployed acoustic receivers into all known connected waterways containing larval sea lamprey rearing habitat (n = 23), including the Detroit River (connecting Lake Erie to Lake Huron) and distributaries to Lake Ontario. Distribution of tagged sea lamprey to putative spawning waterways was shaped by heterogeneous stream attractiveness and distance-limited dispersal. Using parameter estimates from our capture-recapture model and simulation, we predicted survival and dispersal outcomes for a hypothetical sea lamprey population evenly distributed throughout Lake Erie at the beginning of January (34% pre-spawn mortality, 45% dispersal into Lake Erie tributaries, 19% dispersal into the Detroit River, and 2% dispersal into Lake Ontario). The methodology we applied may be widely useful for investigating dispersal and survival of aquatic organisms.

Lake Erie, Lake Ontario↗
USGS2024

Impacts of artificial rearing on cisco Coregonus artedi morphology, including pugheadedness

Cisco ( Coregonus artedi Lesueur, 1818) in the Laurentian Great Lakes declined throughout the 19th and 20th centuries. Managers are attempting to restore Great Lakes cisco and other coregonines using multiple approaches, including stocking. A potential obstacle to these efforts is that artificially reared coregonines can display deformities and morphological differences compared to wild fish, but the impacts of artificial rearing on cisco morphology are not well understood. We compared morphologies of wild cisco to their artificially reared offspring, including one family that was exposed to three rearing temperature treatments. We found that artificially reared cisco had smaller eyes, shallower bodies, fewer gill rakers, and longer paired fins than their wild parents. We also found that artificially reared cisco were pugheaded, and this result held for another cisco population and rearing facility. Across the temperature treatments we tested, rearing temperatures did not impact the degree of pugheadedness or other morphological differences. Our results have important implications for coregonine restoration efforts. Future work should evaluate whether morphological differences that arise through artificial rearing affect cisco fitness in the wild.

Canadian Journal of Zoology↗
USGS2003

Chemosterilization of male sea lampreys ( Petromyzon marinus ) does not affect sex pheromone release

Release of males sterilized by injection with bisazir is an important experimental technique in management of sea lamprey ( Petromyzon marinus ), an invasive, nuisance species in the Laurentian Great Lakes. Sea lampreys are semelparous and sterilization can theoretically eliminate a male's reproductive capacity and, if the ability to obtain mates is not affected, waste the sex products of females spawning with him. It has been demonstrated that spermiating males release a sex pheromone that attracts ovulating females. We demonstrated that sterilized, spermiating males also released the pheromone and attracted ovulating females. In a two-choice maze, ovulating females increased searching behavior and spent more time in the side of the maze containing chemical stimuli from sterilized, spermiating males. This attraction response was also observed in spawning stream experiments. Also, electro-olfactograms showed that female olfactory organs were equally sensitive to chemical stimuli from sterilized and nonsterilized, spermiating males. Finally, fast atom bombardment mass spectrometry showed that extracts from water conditioned with sterilized and nonsterilized, spermiating males contained the same pheromonal molecule at similar levels. We concluded that injection of bisazir did not affect the efficacy of sex pheromone in sterilized males.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS1994

Dramatic decline of unionid bivalves in offshore waters of western Lake Erie after infestation by the zebra mussel, Dreissena polymorpha

Unionid bivalves and attached epizoic zebra mussels ( Dreissena polymorpha ) were collected at one index station in 1989, 1990, and 1991 and at 17 stations in 1991 in offshore waters of western Lake Erie of the Laurentian Great Lakes. Sampling at the index station revealed that the proportion of live unionids declined from 53% in September 1989 to 17% in May–June 1990 and to 0% in September 1990: this 100% mortality coincided with heavy infestation by zebra mussels. Quantitative sampling with a Ponar grab at the 17 stations in 1991 revealed a widespread and dramatic reduction in unionid populations. In 1982, five unionid species occurred at 35% of the stations at a density of 4/m 2 , whereas in 1991, no live unionid species were found. Qualitative sampling with an epibenthic sled at the 17 stations in 1991 yielded only 4 live specimens of 2 species ( Amblema plicata plicata and Fusconaia flava ) and 187 dead specimens of 10 species. These and other results indicate that unionid populations are being negatively affected by zebra mussels in the Great Lakes. Similar impacts on unionids are expected to occur where zebra mussels become abundant throughout North America.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2024

Evaluation of larval sea lamprey Petromyzon marinus growth in the laboratory: Influence of temperature and diet

Conservation aquaculture provides a means for promoting environmental stewardship, useful both in the context of restoring native species and limiting the production of invasive species. Aquaculture of lampreys is a relatively recent endeavor aimed primarily at producing animals to support the restoration of declining native populations. However, in the Laurentian Great Lakes, where sea lamprey Petromyzon marinus are invasive, the ability to acquire a reliable source of certain life stages would be a significant benefit to those controlling their populations and studying the species. Here, we apply methodologies developed for Pacific lamprey Entosphenus tridentatus restoration to investigate the feasibility of rearing larval sea lamprey under laboratory conditions. In two experiments lasting 3 and 9 months, we tested the effects of different dietary sources and water temperature (ambient and controlled) on the survival and growth of wild-caught larvae. Rearing conditions had no effect on mortality, as larval survival was 100% in both experiments. Growth was significantly affected by water temperature, with the highest average daily growth rates observed at 22 and 15°C (0.14 mm day −1 ) and lowest at 8°C (0.06 mm day −1 ). Diets of yeast alone (0.19 and 0.21 g L −1 ) performed better than those comprising a mixture of yeast and other material when fed 3 times weekly (rice flour, wheat flour, fish meal; 0.19 and 0.32 g L −1 ). Averaged across the three constant temperatures (8, 15, and 22°C), larvae fed on yeast grew 0.13 mm day −1 and 0.01 g day −1 , whereas on yeast + fish meal, they grew 0.09 mm day −1 and 0.01 g day −1 . At ambient temperature (4–20°C), larvae fed on yeast grew 0.15 mm day −1 and 0.01 g day −1 , whereas those fed on yeast + wheat flour grew 0.13 mm day −1 and 0.008 g day −1 and those fed on yeast + rice flour grew 0.12 mm day −1 and 0.009 g day −1 . An experimental duration of 90 days was sufficient to detect significant changes to larval sea lamprey growth stemming from temperature variation. Overall, rearing of sea lamprey in captivity appears feasible at low density (31–32 g m −2 and 17–25 larvae m −2 ), but uncertainties remain regarding the most appropriate means of providing adequate feed for these fish in high-density conditions.

Aquaculture Research↗
USGS2014

Distribution and population genetics of walleye and sauger

Conserving genetic diversity and local adaptations are management priorities for wild populations of exploited species, which increasingly are subject to climate change, habitat loss, and pollution. These constitute growing concerns for the walleye Sander vitreus, an ecologically and economically valuable North American temperate fish with large Laurentian Great Lakes' fisheries. This study compares genetic diversity and divergence patterns across its widespread native range using mitochondrial (mt) DNA control region sequences and nine nuclear DNA microsatellite (μsat) loci, examining historic and contemporary influences. We analyze the genetic and morphological characters of a putative endemic variant– “blue pike” S. v. “glaucus” –described from Lakes Erie and Ontario, which became extinct. Walleye with turquoise-colored mucus also are evaluated, since some have questioned whether these are related to the “blue pike”.

BMC Evolutionary Biology↗
USGS2017

Estimating incision healing rate for surgically implanted acoustic transmitters from recaptured fish

Background Intracoelomic implantation of electronic tags has become a common method in fishery research, but rarely are fish examined by scientists after release to understand the extent that surgical incisions have healed. Walleye ( Sander vitreus ) are a valuable, highly exploited fishery resource in the Laurentian Great Lakes. Here, fishery capture of walleye with internal acoustic transmitters combined with a high reward program provided multiple opportunities to examine photographs and quantify the status of surgical incisions. Walleye ( n = 926) from reef and river spawning populations in Lake Erie and Lake Huron were implanted with acoustic transmitters during spring spawning events from 2011 to 2016. Incisions were closed with polydioxanone monofilament using two to three interrupted sutures. Out of 276 recaptured fish, 60 incision sites were clearly visible in photographs, and these were scored by two independent readers for incision closure, inflammation, and the presence of sutures. Results While incision sites were completely closed by 61 days post-release (95% CI 44–94), sutures remained for up to 866 days. Sutures were expelled serially during a protracted period, and the probability of observing at least one suture in a recaptured fish declined below 50% after 673 days (95% CI 442–1016). Inflammation at the incision increased during the first 71 days and then declined monotonically, remaining detectable at low levels. Conclusion Our results emphasized that sutures remained in free-ranging fish past the time when they were beneficial for incision healing. Most dissolvable sutures have been designed for use in endotherms where the body temperature and internal milieu differ dramatically from the conditions experienced by fishes in temperate climates. Identification of new suture materials for fish that facilitate healing while absorbing or dissolving in a reasonable period (e.g., a few weeks to three months) in colder temperatures (e.g., <12 °C) would be beneficial to mitigate potential adverse impacts from inflammation at the incision.

Animal Biotelemetry↗
USGS2024

A comparison of survival and behavior of lake whitefish following transmitter implantation using electro- or chemical immobilization

Background The number of telemetry studies focused on lake whitefish ( Coregonus clupeaformis ) in the Laurentian Great Lakes has steadily increased over the last decade, but field tests of immobilization methods used for tag implantation, which have the potential to affect survival and behavior of fish after release, are lacking. We compared post-tagging survival and behavior of lake whitefish that were immobilized for tag implantation using electroimmobilization via a transcutaneous electrical nerve stimulation (TENS) unit or by chemical immobilization via exposure to 10% eugenol. Results Acoustic tags were implanted into 126 adult lake whitefish ( N = 126; N = 67 TENS treatment group, N = 59 eugenol treatment group) collected from the Fox River, Wisconsin, during the spawning period in November 2021. We found no significant differences between treatments in the number of days that lake whitefish spent in the Fox River following tagging (TENS mean = 13.4 days, eugenol mean = 14.7), and also found that the proportions of fish within each treatment group that returned to the Fox River during fall 2022 (51% from TENS treatment group, 49% from eugenol treatment group) did not differ from the proportions for all fish that were confirmed to be alive at that time. The best Cormack–Jolly–Seber model indicated no differences in survival between the two treatment groups (monthly survival = 0.980, 95% CI 0.970–0.987). Fish immobilized using TENS underwent almost immediate induction and recovery from surgeries, while fish immobilized using eugenol had induction times that ranged 167–487 s (mean = 347 s) and recovery times that ranged 51–2358 s (mean = 1242 s). Conclusions Short- and long-term behavior (time to exit of Fox River, return to Fox River in the next spawning season) and monthly survival estimates of lake whitefish did not differ between the immobilization treatments. Either method may be suitable for immobilization during tag implantation, but the additional time needed for induction and recovery of fish when using eugenol may be a limiting factor in some field-based tagging situations.

Wisconsin↗
USGS2013

Early responses to zebra mussels in the Great Lakes: a journey from information vacuum to policy and regulation

Invasive species such as zebra mussels pose a threat to the economies and environments of coastal and fresh-water habitats around the world. Consequently, it is important that government policies and programs be adequate to protect these waters from invaders. This chapter documents key events that took place in the early years (1988-1991) of zebra mussel colonization of the Laurentian Great Lakes and evaluates government responses (policies and programs) to this disruptive, invasive, freshwater species.

Book chapter↗
USGS2013

Chronological history of zebra and quagga mussels (Dreissenidae) in North America, 1988-2010

An unprecedented invasion began in North America in the mid-/late-1980s when two Eurasian mussel species, Dreissena polymorpha (zebra mussel) and Dreissena rostriformis bugensis (quagga mussel), became established in Laurentian Great Lakes. It is believed that Lake Erie was the initial location of establishment for both species, and within 3 years, zebra mussels had been found in all the Great Lakes. Since 1986, the combined distribution of two dreissenids has expanded throughout the Great Lakes region and the St. Lawrence River in Canada and also in the United States from the Great Lakes to the Mississippi Basin including Arkansas, Cumberland, Illinois, Missouri, Ohio, and Tennessee river basins. The distribution of dreissenid mussels in the Atlantic drainage has been limited to the Hudson and Susquehanna rivers. In the western United States, the quagga mussel established a large population in the lower Colorado River and spread to reservoirs in Arizona, California, Colorado, Nevada, and Utah. Overall, dreissenid species have been documented in 131 river systems and 772 inland lakes, reservoirs, and impoundments in the United States.

Book chapter↗
USGS2016

Evidence for partial overlap of male olfactory cues in lampreys

Animals rely on a mosaic of complex information to find and evaluate mates. Pheromones, often comprised of multiple components, are considered to be particularly important for species-recognition in many species. While the evolution of species-specific pheromone blends is well-described in many insects, very few vertebrate pheromones have been studied in a macro-evolutionary context. Here, we report a phylogenetic comparison of multi-component male odours that guide reproduction in lampreys. Chemical profiling of sexually mature males from eleven species of lamprey, representing six of ten genera and two of three families, indicated the chemical profiles of sexually mature male odours are partially shared among species. Behavioural assays conducted with four species sympatric in the Laurentian Great Lakes indicated asymmetric female responses to heterospecific odours, where Petromyzon marinus were attracted to male odour collected from all species tested but other species generally preferred only the odour of conspecifics. Electro-olfactogram recordings from P. marinus indicated that although P. marinus exhibited behavioural responses to odours from males of all species, at least some of the compounds that elicited olfactory responses were different in conspecific male odours compared to heterospecific male odours. We conclude that some of the compounds released by sexually mature males are shared among species and elicit olfactory and behavioural responses in P. marinus , and suggest that our results provide evidence for partial overlap of male olfactory cues among lampreys. Further characterization of the chemical identities of odour components is needed to confirm shared pheromones among species.

Journal of Experimental Biology↗
USGS2023

Lessons learned in applying decision analysis to natural resource management for high stakes issues surrounded by uncertainty

Management agencies are tasked with difficult decisions for conservation and management of natural resources. These decisions are difficult because of ecological and social uncertainties, the potential for multiple decision makers from multiple jurisdictions, and the need to account for the diverse values of stakeholders. Decision analysis provides a framework for accounting for these difficulties when making conservation and management decisions. We discuss the benefits of the application of decision analysis for these types of issues and provide insights from three case studies from the Laurentian Great Lakes. These case studies describe applications of decision analysis for decisions within an agency (management of double-crested cormorant), among agencies (response to invasive grass carp), and among agencies and stakeholders (sustainable fisheries harvest management). These case studies provide insight into the ways that decision analysis can be useful for conservation and management of natural resources, but we also highlight future needs for decision making for these resources. In particular, applications of decision analysis for conservation and management would benefit from enhanced integration of both ecological and social science, inclusion of a broader base of stakeholders and rightsholders, and better educational opportunities surrounding decision analysis for undergraduates and graduate students of natural resources management programs. Specific lessons from our experiences include the importance of establishing trust and transparency early through the formation of a working group, collaboratively defining objectives and evaluating uncertainties, risks, and tradeoffs, and implementing participatory modeling processes with an independent facilitator with appropriate quantitative skills.

Decision Analysis↗
USGS2003

Tidal-bundle sequences in the Jordan Sandstone (Upper Cambrian), southeastern Minnesota, U.S.A.: Evidence for tides along inboard shorelines of the Sauk Epicontinental Sea

This study documents for the first time tidal bundling in a lower Paleozoic sheet sandstone from the cratonic interior of North America, providing insights into the hydrodynamics of ancient epicontinental seas. The Jordan Sandstone (Upper Cambrian) in the Upper Mississippi Valley contains large-scale planar tabular cross-sets with tidal-bundle sequences, which were analyzed in detail at an exceptional exposure. Tidal-bundle sequences (neap-spring-neap cycles) were delineated by foreset thickening-thinning patterns and composite shale drapes, the latter of which represent accumulations of mud during the neap tides of neap-spring-neap tidal cycles. Fourier analysis of the bundle thickness data from the 26 measurable bundle sequences revealed cycles ranging from 15 to 34 bundles per sequence, which suggests a semidiurnal or mixed tidal system along this part of the Late Cambrian shoreline. We extend the tidal interpretation to widespread occurrences of the same facies in outcrops of lesser quality, where the facies is recognizable but too few bundles are exposed for tidal cycles to be measured. By doing so, this study shows that tidally generated deposits have a significant geographic and temporal extent in Upper Cambrian strata of central mid-continent North America. The deposition and preservation of tidal facies was related to the intermittent development of shoreline embayments during transgressions. The tidally dominated deposits filled ravined topographies that were repeatedly developed on the updip parts of the shoreface. Resulting coastal geomorphologies, accompanied perhaps by larger-scale changes in basinal conditions and/or configuration, led to changes in depositional conditions from wave-dominated to tide-dominated. Outcrops of the Jordan Sandstone tidal facies in the Upper Mississippi Valley represent the farthest inboard recorded transmission of ocean-generated tides in the Laurentian epicontinental seas, demonstrating that tidal currents were significant agents in the transport of sand along the far cratonic interior shorelines of Cambrian North America. The results of this study improve the facies-level understanding of the genesis of sheet sandstones. Furthermore, tidalites documented here occur in a specific position within a sequence stratigraphic architecture for the Jordan Sandstone. This provides a framework to compare these ancient deposits and processes to younger (e.g., Carboniferous) epicontinental systems where stratal and sediment dynamics are better documented.

Illinois, Indiana, Iowa, Michigan, Minnesota, Miss↗
USGS2012

Biostratigraphy and chronostratigraphy of the Cambrian-Ordovician great American carbonate bank

The carbonate strata of the great American carbonate bank (GACB) have been subdivided and correlated with ever-increasing precision and accuracy during the past half century through use of the dominant organisms that evolved on the Laurentian platform through the Cambrian and the Ordovician. Trilobites and conodonts remain the primary groups used for this purpose, although brachiopods, both calcareous and phosphatic, and graptolites are very important in certain facies and intervals. A series of charts show the chronostratigraphic units (series and stages) currently in use for deposits of the GACB and the biostratigraphic units (zones, subzones, and biomeres) whose boundaries delineate them. Older and, in some cases obsolete, stages and faunal units are included in the figures to allow users to relate information from previous publications and/or industry databases to modern units. This chapter also provides a brief discussion on the use of biostratigraphy in the recognition and interregional correlation of supersequence boundaries within the Sauk and Tippecanoe megasequences, and the varied perspectives on the nature of biostratigraphic units and their defining taxa during the past half century. Also included are a concise update on the biomere concept, and an explanation of the biostratigraphic consequences of a profound change in the dynamics of extinction and replacement that occurred on the GACB in the Early Ordovician when the factors responsible for platformwide biomere-type extinctions faded and ultimately disappeared. A final section addresses recent and pending refinements in the genus and species taxonomy of biostratigraphically significant fossil groups, the potential they hold for greatly improved correlation, and the obstacles to be overcome for that potential to be realized.

AAPG Memoir↗
USGS2013

Rivermouth alteration of agricultural impacts on consumer tissue δ 15 N

Terrestrial agricultural activities strongly influence riverine nitrogen (N) dynamics, which is reflected in the δ 15 N of riverine consumer tissues. However, processes within aquatic ecosystems also influence consumer tissue δ 15 N. As aquatic processes become more important terrestrial inputs may become a weaker predictor of consumer tissue δ 15 N. In a previous study, this terrestrial-consumer tissue δ 15 N connection was very strong at river sites, but was disrupted by processes occurring in rivermouths (the ‘rivermouth effect’). This suggested that watershed indicators of N loading might be accurate in riverine settings, but could be inaccurate when considering N loading to the nearshore of large lakes and oceans. In this study, the rivermouth effect was examined on twenty-five sites spread across the Laurentian Great Lakes. Relationships between agriculture and consumer tissue δ 15 N occurred in both upstream rivers and at the outlets where rivermouths connect to the nearshore zone, but agriculture explained less variation and had a weaker effect at the outlet. These results suggest that rivermouths may sometimes be significant sources or sinks of N, which would cause N loading estimates to the nearshore zone that are typically made at discharge gages further upstream to be inaccurate. Identifying definitively the controls over the rivermouth effect on N loading (and other nutrients) will require integration of biogeochemical and hydrologic models.

Great Lakes↗
USGS2013

Aspects of embryonic and larval development in bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix

As bighead carp Hypophthalmichthys nobilis and silver carp H. molitrix (the bigheaded carps) are poised to enter the Laurentian Great Lakes and potentially damage the region’s economically important fishery, information on developmental rates and behaviors of carps is critical to assessing their ability to establish sustainable populations within the Great Lakes basin. In laboratory experiments, the embryonic and larval developmental rates, size, and behaviors of bigheaded carp were tracked at two temperature treatments, one “cold” and one “warm”. Developmental rates were computed using previously described stages of development and the cumulative thermal unit method. Both species have similar thermal requirements, with a minimum developmental temperature for embryonic stages of 12.1° C for silver carp and 12.9° C for bighead carp, and 13.3° C for silver carp larval stages and 13.4° C for bighead carp larval stages. Egg size differed among species and temperature treatments, as egg size was larger in bighead carp, and “warm" temperature treatments. The larvae started robust upwards vertical swimming immediately after hatching, interspersed with intervals of sinking. Vertical swimming tubes were used to measure water column distribution, and ascent and descent rates of vertically swimming fish. Water column distribution and ascent and descent rates changed with ontogeny. Water column distribution also showed some diel periodicity. Developmental rates, size, and behaviors contribute to the drift distance needed to fulfill the early life history requirements of bigheaded carps and can be used in conjunction with transport information to assess invasibility of a river.

PLoS ONE↗