Geology topics

Research about Canada, United States

Source-linked reports with geographic coverage including Canada, United States.

At least 433 records · Page 24Linked to original sources

USGS2021

Estimating age and growth of invasive sea lamprey: A review of approaches and investigation of a new method

We review recent advances in age and growth estimation of invasive sea lamprey ( Petromyzon marinus ) in the Great Lakes and present a more accurate method for growth estimation. To forecast growth and prioritize streams for control actions, sea lamprey managers currently use an average daily growth model. Here, a new linear model that included stream and lake as contributing variables was investigated and found to outperform the currently used growth model (roughly a 10 mm difference at age 1). Length-at-age of larvae between ages 1 and 4 were also best forecasted by a linear model with the predictor variables including growing degree days, stream, lake, and larval lamprey density. The model predicts that larval sea lamprey grow faster in warm streams with low densities of lamprey larvae. More accurate growth models could allow sea lamprey control managers to improve decisions concerning how sea lamprey control effort is allocated among streams, and could help inform broader modeling efforts evaluating the population demographics of a lake-wide populations exposed to varying control and environmental scenarios. Priority areas for research include investigating if temperatures have increased in sea lamprey-producing streams in response to climate change, using close-kin mark-recapture to mark family groups at age 1 to age large larvae and transformers years later, and determining if sex determination is environmentally mediated by larval growth and density.

Great Lakes↗

USGS2021

Identifying sources and year classes contributing to invasive grass carp in the Laurentian Great Lakes

Relative contributions of aquaculture-origin and naturally-reproduced grass carp ( Ctenopharyngodon idella ) in the Laurentian Great Lakes have been unknown. We assessed occurrence and distribution of aquaculture-origin and wild grass carp in the Great Lakes using ploidy and otolith stable oxygen isotope (δ 18 O) data. We inferred natal river and dispersal from natal location for wild grass carp using otolith microchemistry and estimated ages of wild and aquaculture-origin fish to infer years in which natural reproduction and introductions occurred. Otolith δ 18 O indicated that the Great Lakes contain a mixture of wild grass carp and both diploid and triploid, aquaculture-origin grass carp. Eighty-eight percent of wild fish (n = 49 of 56) were caught in the Lake Erie basin. Otolith microchemistry indicated that most wild grass carp likely originated in the Sandusky or Maumee rivers where spawning has previously been confirmed, but results suggested recruitment from at least one other Great Lakes tributary may have occurred. Three fish showed evidence of movement between their inferred natal river in western Lake Erie and capture locations in other lakes in the Great Lakes basin. Age estimates indicated that multiple year classes of wild grass carp are present in the Lake Erie basin, recruitment to adulthood has occurred, and introductions of aquaculture-origin fish have happened over multiple years. Knowledge of sources contributing to grass carp in the Great Lakes basin will be useful for informing efforts to prevent further introductions and spread and to develop strategies to contain and control natural recruitment.

Michigan, New York, Ohio, Ontario↗

USGS2021

Assessing the assumptions of classification agreement, accuracy, and predictable healing time of sea lamprey wounds on lake trout

Sea lamprey control in the Laurentian Great Lakes relies on records of sea lamprey wounds on lake trout to assess whether control efforts are supporting fisheries management targets. Wounding records have been maintained for 70 years under the assumption that they are a reliable and accurate reflection of sea lamprey damage inflicted on fish populations. However, two key assumptions underpinning the use of these data need thorough evaluation: sea lamprey wounds follow a predictable healing progression, and individuals classify wounds accurately and reliably. To assess these assumptions, we conducted a workshop where experienced professionals examined lake trout with known sea lamprey wounds. For most lake trout, pictures were taken at regular intervals during the healing process. Our evaluation of wound pictures found high variability in healing times and wound progressions that did not conform to the currently used classification system. Participants’ wound classification agreement and accuracy were low and misclassification rates were high for most wound types. Training provided during the workshops did not markedly improve these metrics. We assessed wound classification accuracy for the first time and found assumptions of high accuracy and agreement are not met. We recommend misclassification rates be incorporated into models using wound data, sensitivity analyses be conducted to assess the potential impact of wound misclassification on estimates of key metrics (such as sea lamprey-induced mortality for lake trout), and alternative biomarkers be developed to quantify wound status with greater accuracy and precision.

Laurentian Great Lakes↗

USGS2021

Registration and application of sea lamprey pheromones for sea lamprey control in the United States and Canada

Since the identification of 3-trifluoromethyl-4-nitrophenol as a lampricide in the 1950s, control of sea lamprey populations in the Great Lakes has largely relied on lampricides, barriers, and traps. Lampricide treatments target larval lampreys in tributaries of the Great Lakes. The Great Lakes Fishery Commission oversees sea lamprey control efforts and has invested in technologies that may target other life stages to provide a more integrated approach to sea lamprey control. One technology under development is the use of pheromones to alter behavior of spawning adults. Pheromones are considered biopesticides , which are substances made from naturally occurring products, or derived from living organisms, or a microorganism, that controls pests. We provide a review of sea lamprey management that led to the development of pheromone registration. We also describe the process used to register the first vertebrate pheromone, 3-ketopetromyzonal-24-sulfate (3kPZS) in the United States and Canada and its potential uses in sea lamprey control as a supplemental tool to chemical lampricides.

Journal of Great Lakes Research↗

USGS2021

Winter severity, fish community, and availability to traps explain most of the variability in estimates of adult sea lamprey in Lake Superior

Animal populations are assessed to estimate rates of artificial and natural mortality at ecologically relevant spatial and temporal scales to develop exploitation quotas. But how the population’s natural mortality rate and how the ability to observe the population changes through time are poorly understood in most invasive fishes, despite efforts to control their populations. By investigating a 30-year abundance index of invasive sea lamprey ( Petromyzon marinus ) in Lake Superior, we found that the index was highly correlated (R 2 = 0.75) with biotic and abiotic factors hypothesized to influence sea lamprey natural mortality and their availability to index traps. The index was lowest in years (1) following winters with below average ice cover on Lake Superior, (2) when stream discharge during sea lamprey migration was below average, (3) when adult sea lamprey were smaller than average, and (4) when adult sea lamprey were more likely to be distributed in tributaries on the east side of Lake Superior. These results highlight the need for policy makers to consider invasive species abundance indexes not just in the context of control effort, but also in the context of biotic and abiotic conditions because they could markedly influence natural mortality or the ability to observe highly suppressed populations.

Lake Superior↗

USGS2021

Seasonal movements of muskellunge in the St. Clair – Detroit River System: Implications for multi-jurisdictional fisheries management

The St. Clair-Detroit River System contains a world-class Great Lakes muskellunge ( Esox masquinongy ) fishery that has avoided the declines observed in many Great Lakes muskellunge populations. Muskellunge are an upper trophic level predator, and therefore a naturally low-density species. Limited fishery-independent data exist on which to base management decisions. To remedy this, we initiated an acoustic telemetry study in May of 2016, in collaboration with the Great Lakes Acoustic Telemetry Observation System. Our objective was to describe patterns of movement of muskellunge in this large and open system to better understand their spatial ecology. We acoustically tagged 133 muskellunge in the Detroit River and Lake St. Clair, and movements of 58 fish that passed our data quality control screens were analyzed. We utilized mixed modelling to assess the effects of sex, length, release location, and season on daily movement rates. We found that movement rates only differed among seasons, with highest movement rates occurring in the fall and lowest movement rates in the winter. Muskellunge tagged at different locations exhibited distinct residency patterns, and fish frequently crossed jurisdictional and waterbody boundaries. Ultimately our study highlights the scope and patterns of muskellunge movement in a large, unimpounded system and demonstrates that management of these fish would benefit from consideration of their full distribution covering multiple management jurisdictions.

Michigan, Ontario↗

USGS2021

Evidence of successful river spawning by lake trout (Salvelinus namaycush) in the lower Niagara River, Lake Ontario

Restoration of a wild-produced lake trout Salvelinus namaycush population in Lake Ontario has not been successful despite the adult population often meeting or exceeding restoration targets. Lack of high-quality spawning habitat in Lake Ontario is suggested as one impediment to recruitment of wild lake trout, although the quantity and location of spawning habitat is poorly understood. If high-quality spawning habitat is limited in Lake Ontario, lake trout may be using uncommon spawning locations such as rivers. Anecdotal angler accounts point to the Niagara River as a lake trout spawning location. To better understand the potential of the Niagara River as a spawning location, egg and juvenile fish collections were conducted 12–14 river kilometers from the mouth of the Niagara River from 2010 to 2012; and mature female lake trout with surgically implanted acoustic tags were monitored from 2015 to 2019. Genetic analyses confirmed 60% of collected eggs and 93% of collected post-hatch juvenile fish in the Niagara River were lake trout. Tagged female lake trout returned to the Niagara River over consecutive years during the spawning season. The short duration of lake trout presence in the river (mean = 56 days/year) suggests female lake trout use the Niagara River primarily for spawning. Diversity in spawning locations may provide lake trout population’s resilience against environmental variability through a portfolio effect. Improved identification of riverine spawning locations, including their overall contribution to wild recruitment, may be a useful tool for managers to restore a wild-produced population of lake trout in Lake Ontario.

New York, Ontario↗

USGS2021

Stationary hydroacoustics demonstrates vessel avoidance biases during mobile hydroacoustic surveys of alewife in Lake Ontario

Mobile hydroacoustic surveys are routinely used to estimate pelagic fish abundance . In the Great Lakes, alewife are commonly surveyed with mobile hydroacoustics, however, their behavior often has them associated with epilimnetic habitats which increases the potential for vessel avoidance to bias hydroacoustic observations. Abundance estimates from mobile hydroacoustic surveys are typically made using depth and size thresholds to classify targets to species. In hydroacoustic surveys, fish can appear to be smaller when oriented off horizontal axis, as is common with fish displaying vessel avoidance behaviour. This presents a problem where alewives that are diving may appear too small to be correctly classified. We compared alewife swimming behaviours and target strength distributions between stationary up-looking and mobile down-looking hydroacoustics to quantify how vessel avoidance may bias hydroacoustic observations. Alewives from the mobile survey were found to be diving away from the surface, moving faster and in more linear paths than the undisturbed fish from the stationary survey. In the mobile survey, alewives were observed at smaller target strength values than would be expected if boat avoidance was not occurring. Our results suggest that alewife behavioral changes associated with vessel avoidance affect the number and size of targets classified as alewife from mobile hydroacoustic surveys in Lake Ontario.

Lake Ontario↗

USGS2021

Progress towards integrating an understanding of chemical ecology into sea lamprey control

The sea lamprey, Petromyzon marinus , is a destructive invader in the Laurentian Great Lakes that relies on several complex chemical cues to complete their life cycle. The central roles of chemical cues in sea lamprey reproduction provide opportunities to leverage knowledge of sea lamprey chemical ecology when developing alternative or supplemental strategies for sea lamprey control. A solid foundation has been laid regarding sea lamprey chemical ecology, with recent advances in our understanding of the migratory pheromone, male sex pheromone, and alarm cues broadening our fundamental understanding of the diversity, complexity, and evolution of chemical cues used by sea lamprey. Additionally, research applying semiochemicals in differing management scenarios has provided useful insights into the challenges of incorporating chemical cues into the sea lamprey control program. Here, we synthesize new findings related to fundamental research of chemosensory cues along with knowledge learned from management-based tests and explore options for integrating an understanding of chemical ecology into sea lamprey control in light of new knowledge. We also highlight current unknowns and future research needs that should be addressed prior to implementation of sea lamprey chemical ecology into the sea lamprey control program.

Great Lakes↗

USGS2021

What can commercial fishery data in the Great Lakes reveal about juvenile sea lamprey (Petromyzon marinus) ecology and management?

The Laurentian Great Lakes of North America support a large and profitable freshwater fishery, but one continuously beset by parasitism from the invasive sea lamprey ( Petromyzon marinus ). Despite being the life stage that inflicts damage to the fishery, therefore necessitating a bi-national control program, our knowledge of juvenile sea lamprey ecology is poor and their response to control efforts are not assessed. Incidental capture of juvenile sea lamprey by commercial fishers is one means to collect data on this enigmatic life stage, and in Lake Huron such data have been collated since 1967. Here, we explore incidental captures of juvenile sea lamprey and their hosts from northern Lake Huron between 1987 and 2017 ( n = 33,246 observations) to address four objectives. Firstly, we document collection efforts by fishers to provide historical context to the dataset. Secondly, we pose and test a series of questions related to fishery encounter, host selection, growth, distribution, and sex ratio to highlight how these types of data can be informative regarding juvenile sea lamprey ecology. Results presented here could be used to develop biological hypotheses to be addressed in future work. Thirdly, we directly assessed whether juvenile sea lamprey capture data could be useful in corroborating trends observed in adult sea lamprey abundance and wounding, as well as in identifying abundance and wounding hotspots. Lastly, we summarize research and outreach efforts that have benefited from the capture of juvenile sea lamprey in recent years.

Great Lakes↗

USGS2021

Spatial and temporal distributions of Dreissena spp. veligers in Lake Huron: Does calcium limit settling success?

The larval stage of invasive Dreissena spp. mussels (i.e., veligers) are understudied despite their seasonal numerical dominance among plankton. We report the spring and summer veliger densities and size structure across the main basin, North Channel, and Georgian Bay of Lake Huron, and seek to explain spatiotemporal variation. Monthly sampling was conducted at 9 transects and up to 3 sites per transect from spring through summer 2017. Veliger densities peaked in June and July, and we found comparable densities and biomasses of veligers between basins, despite differences in density of juvenile and adult mussels across these regions. Using a generalized additive model to explain variations in veliger density, we found that temperature, chlorophyll a , and nitrates/nitrites were most important. We generated an index of veliger attrition based on size distributions that revealed a higher rate of attrition in the North Channel than the rest of the lake. A logistic model indicated a threshold calcium concentration of around 22 mg/L was necessary for veligers to survive to larger sizes and recruit to their juvenile and benthic adult life stages. Improved understanding of factors that regulate the production and survival of Dreissena veligers could improve the ability of managers to assess future invasion threats as well as explore potential control options.

Lake Huron↗

USGS2021

Understanding sea lamprey populations in the Great Lakes prior to broad implementation of sea lamprey control

Control of invasive sea lamprey in the Great Lakes with a selective pesticide (lampricide) that targeted larval sea lamprey began in the late 1950's and continues to be one of the main methods for control. Although the Great Lakes Fishery Commission, which was formed with the mandate of controlling sea lamprey, often expresses the success of the sea lamprey control program in terms of percent reduction from lake-wide pre-lampricide control adult sea lamprey abundances, there remains a large amount of uncertainty surrounding these estimates. In this study, we gathered historical data on adult sea lamprey captures from trapping efforts from the mid-1950's through the late 1970's to better understand pre-control abundance. We used this information to estimate lake-wide population abundances of adult sea lamprey using a weighted linear regression that includes environmental and lampricide treatment predictor variables. We varied trapping efficiency for early trapping data to evaluate the uncertainty in abundance estimates. Pre-control adult sea lamprey abundances in all lakes were much greater than current population sizes, but estimates were quite sensitive to trapping efficiency. In Lake Superior, declines in abundance aligned with increases in control efforts, but in other lakes, declines were occurring prior to the onset of lampricide application, perhaps because of a loss of prey. We suggest that previous estimates of pre-control adult sea lamprey abundance may have been underestimated unless trapping efficiency was greater than what is currently achieved in the basin.

Great Lakes↗

USGS2021

Trade-offs between suppression and eradication of sea lampreys from the Great Lake

Ecosystem managers confronted with newly invasive species may respond with a program of suppression or eradication. Suppression of an invasive species refers to management of a species such that its effect on other biota in the local ecosystem is acceptable. Eradication is the removal of all individuals of a species from a defined region. We examine the cost and benefit trade-offs between suppression and eradication of Laurentian Great Lakes sea lampreys ( Petromyzon marinus ) based on discussions at the 3rd Sea Lamprey International Symposium (held in 2019). Substantial effort has been expended annually since the 1960s to suppress sea lampreys in the Great Lakes basin. Choosing between suppression and eradication is a value judgement, ideally made jointly by scientists, decision-makers, stakeholders, and society. Successful large-scale eradications have been limited to a small number of cases for which the cost to human society justified and supported the long-term commitment necessary for success. The greatest challenge to successful eradication of sea lampreys from the Great Lakes may be a suitable social, political, legal, and institutional environment. Preparations could be made now for a transition in which public pushback on current control methods (pesticide applications and barriers to fish passage) leads to more extensive use of an alternative control method, such as genetic control.

Great Lakes and Saint Lawrence River areas↗

USGS2021

Quantifying Great Lakes sea lamprey populations using an index of adults

Effective control of aquatic invasive species requires knowledge of the population throughout the infested area. Lake-wide assessments of invasive sea lampreys ( Petromyzon marinus ) are used to assess their status in the Laurentian Great Lakes, informing fisheries managers and decision makers in the sea lamprey control program. Initially these assessments focused on an estimate of absolute abundance, but later switched to an estimate of relative abundance as an index. In this paper, we describe the recently developed index of sea lamprey abundance and the reasons for its use. Rather than trying to estimate spawning run sizes of all Great Lakes tributaries, the index instead estimates run sizes of a small subset of index streams. Streams chosen for the index had large spawning runs and a history of trapping operations that consistently yielded mark-recapture estimates. This change enabled the sea lamprey control program to abandon a previously used regression model that predicted run size on streams with no sea lamprey traps. Further research is needed to determine how strongly correlated the index is with actual patterns in the lake-wide population of adult sea lampreys.

Lake Erie, Lake Huron, Lake Michigan, Lake Ontario↗

USGS2021

Enhancing Great Lakes coastal ecosystems research by initiating engagement between scientists and decision-makers

A disconnect between scientific research and environmental management communities can be a detriment to both. In the case of Great Lakes coastal ecosystems, which are inherently complex and subject to uncertain effects of future climatic, environmental, and anthropogenic drivers, greater collaboration could be beneficial to their sustainability. We capture the challenges and opportunities identified by a scientist/decision-maker co-production workshop focused on the future environmental quality of Great Lakes coastal wetlands. We explain our path through the stakeholder workshop process, our challenges in translating meeting outcomes into actionable items, and lessons learned to bridge gaps between scientists and decision-makers. Additionally, we determine topics and directions identified by decision-makers that can be modeled with existing technologies and others that require further research. These topics may be incorporated into future research efforts and could serve as a shortlist of research priorities that were identified by decision-makers working with coastal wetland issues. Based on lessons learned during and after the workshop, we provide suggestions for bridging the gap between researchers and decision-makers, including sustained engagement between these groups and improved interaction through the beginning, duration, and end of research and/or management efforts.

Great Lakes↗

USGS2021

Incorporation of non-native species in the diets of cisco (Coregonus artedi) from eastern Lake Ontario

Cisco Coregonus artedi was once an important native fish in Lake Ontario; however, after multiple population crashes, the cisco stock has yet to recover to historic abundances. Rehabilitation of cisco in Lake Ontario is a fish community management objective, but the extent to which recent non-native species and pelagic food web changes have influenced cisco is not well understood. We described cisco diets in contemporary Lake Ontario following the addition and spread of non-native zooplankton species. We collected 618 cisco and processed 178 for full diet analysis in eastern Lake Ontario using mid-water trawls and bottom-set gill nets from 2016 to 2020. We found that Lake Ontario cisco were mostly zooplanktivorous, and non-native zooplankton dominated their diet during July and September. Cisco smaller than 300 mm had a more diverse diet including both native and non-native zooplankton, while cisco larger than 300 mm fed almost exclusively on non-native predatory cladocerans Bythotrephes longimanus and Cercopagis pengoi (98.9% consumed prey dry mass). We also found fish eggs, presumed to be of coregonine origin in 75% of non-empty December-collected cisco diets, suggesting eggs subsidize cisco diets when available. Juvenile round goby Neogobius melanostomus , alewife Alosa pseudoharengus and rainbow smelt Osmerus mordax were found in 2% of all analyzed non-empty stomachs. Lake Ontario cisco diet appears to be more similar to zooplanktivorous Lake Superior cisco than Lake Michigan where piscivory is prevalent. Lake Ontario cisco diets reflected zooplankton community changes indicating that non-native predatory cladocerans are now an important energy source supporting this native species.

Eastern Lake Ontario↗

USGS2021

Response of fish assemblages to restoration of rapids habitat in a Great Lakes connecting channel

Rapids habitats are critical spawning and nursery grounds for multiple Laurentian Great Lakes fishes of ecological importance such as lake sturgeon, walleye, and salmonids. However, river modifications have destroyed important rapids habitat in connecting channels by modifying flow profiles and removing large quantities of cobble and gravel that are preferred spawning substrates of several fish species. The conversion of rapids habitat to slow moving waters has altered fish assemblages and decreased the spawning success of lithophilic species. The St. Marys River is a Great Lakes connecting channel in which the majority of rapids habitat has been lost. However, rapids habitat was restored at the Little Rapids in 2016 to recover important spawning habitat in this river. During the restoration, flow and substrate were recovered to rapids habitat. We sampled the fish community (pre- and post-restoration), focusing on age-0 fishes in order to characterize the response of the fish assemblage to the restoration, particularly for species of importance (e.g. lake whitefish, walleye, Atlantic salmon). Following restoration, we observed a 40% increase in age-0 fish catch per unit effort , increased presence of rare species, and a shift in assemblage structure of age-0 fishes (higher relative abundance of Salmonidae, Cottidae, and Gasterosteidae). We also observed a “transition” period in 2017, in which the assemblage was markedly different from the pre- and post-restoration assemblages and was dominated by Catostomidae. Responses from target species were mixed, with increased Atlantic salmon abundance, first documented presence of walleye and no presence of lake sturgeon or Coregoninae.

Michigan, Ontario↗

USGS2021

The path toward consistent achievement of sea lamprey abundance and lake trout marking targets in Lake Ontario, 2000–2019

Lake Ontario boasts a diverse fish community comprised of native and introduced species that support vibrant recreational, commercial and Indigenous fisheries. The effective delivery of a program to assess and control the sea lamprey ( Petromyzon marinus ) is crucial to achievement of Lake Ontario Fish Community Objectives of rehabilitating native fish stocks while protecting and maintaining the abundance of introduced salmonines. During 2000–2019, the Great Lakes Fishery Commission (GLFC) and its control agents, Fisheries and Oceans Canada (DFO) and the U. S. Fish and Wildlife Service (USFWS), delivered a consistent program of sea lamprey assessment and control. Beginning in 2004, rising sea lamprey abundance and marking rates on lake trout ( Salvelinus namaycush ) in Lake Ontario coincided with a decline of large lake trout in gillnet surveys. Efforts were undertaken to identify and control important sources of juvenile sea lampreys, including larvae that survived treatment, inhabited deepwater areas, or colonised previously uninhabited stream reaches and tributaries. A renewed reliance on proven conventional controls, including lampricide treatments and barriers, has resulted in consistent suppression of sea lamprey abundance and lake trout marking to prescribed targets in Lake Ontario during 2014–2019. This achievement is unprecedented in the 49-year history of Sea Lamprey Control Program delivery in Lake Ontario, and is attributable to the collaborative efforts of the GLFC, the control agents, and federal, provincial, state, and Indigenous partners.

Lake Ontario↗