Geology topics

Ralph Lampman

Publications and source records attributed to Ralph Lampman.

6 recordsLinked to original sources

USGS2025

New technology for an ancient fish: A lamprey life cycle modeling tool with an R Shiny application

Lampreys (Petromyzontiformes) are an ancient group of fishes with complex life histories. We created a life cycle model that includes an R Shiny interactive web application interface to simulate abundance by life stage. This will allow scientists and managers to connect available demographic information in a framework that can be applied to questions regarding lamprey biology and conservation. We used Pacific lamprey ( Entosphenus tridentatus ) as a case study to highlight the utility of this model. We applied a global sensitivity analysis to explore the importance of individual life stage parameters to overall population size, and to better understand the implications of existing gaps in knowledge. We also provided example analyses of selected management scenarios (dam passage, fish translocations, and hatchery additions) influencing Pacific lamprey in fresh water. These applications illustrate how the model can be applied to inform conservation efforts. This tool will provide new capabilities for users to explore their own questions about lamprey biology and conservation. Simulations can hone hypotheses and predictions, which can then be empirically tested in the real world.

PLoS ONE↗

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↗

USGS2024

New technology for an ancient fish: A lamprey life cycle modeling tool with an R Shiny application

Lampreys (Petromyzontiformes) are an ancient group of fishes with complex life histories. We created a life cycle model that includes an R Shiny interactive web application interface to simulate abundance by life stage. This will allow scientists and managers to connect available demographic information in a framework that can be applied to questions regarding lamprey biology and conservation. We used Pacific lamprey (Entosphenus tridentatus) as a case study to highlight the utility of this model. We applied a global sensitivity analysis to explore the importance of individual life stage parameters to overall population size, and to better understand the implications of existing gaps in knowledge. We also provided example analyses of selected management scenarios (dam passage, fish translocations, and hatchery additions) influencing Pacific lamprey in fresh water. These applications illustrate how the model can be applied to inform conservation efforts. This tool will provide new capabilities for users to explore their own questions about lamprey biology and conservation. Simulations can hone hypotheses and predictions, which can then be empirically tested in the real world.

EcoEvoRxiv↗

USGS2024

Defining sediment handling practices to limit negative impacts to larval lampreys

Sediment manipulation activities such as dredging and restoration efforts (e.g., culvert install/repair) may disturb habitats where larval lampreys live burrowed in stream sediments. Sediment added on top of larval lamprey burrowing areas results in ‘overburden’, which poses risks of mortality from respiratory distress, reduced movement, and crushing injuries or may have sublethal effects such as changes in growth or burrowing activity. To avoid negative outcomes, larvae must be able to vertically migrate through the overburden to reach areas near the new (elevated) sediment-water interface. Current guidance on how to limit negative impacts to lampreys during sediment handling activities is limited by a lack of information on how lampreys respond to overburden. The goal of this study was to evaluate larval lamprey responses to variable overburden depths and exposure durations using two sediment types: fine (<0.250 mm) and sand (0.250 - 0.500 mm). We assessed lamprey (mix of Pacific Lamprey Entosphenus tridentatus and Lampetra spp.) survival and injury and evaluated burrowing performance as an indicator of sublethal impacts of overburden stress. We designed an experimental system using 15-cm diameter plastic tubes partitioned into sections that allowed us to describe the approximate vertical position of larval lampreys within the overburden so we could assess vertical migration ability. The tube sections were stacked in a column and secured using straps. The bottom tube section was 10 cm tall and was attached to a flat, rectangular base plate. This section was filled with sediment and lampreys at the start of a test. The middle tube sections were each 10 cm tall, with the number of sections adapted to the depth of the overburden. The top tube section was 20 cm tall to allow room for 10 cm of water over the surface of the overburden. Sampling involved removing the tubes from a holding tank and quickly separating the sections to locate lampreys and assign their position to the tube section where they were recovered. Our primary objectives for the study were to better understand how depth of overburden and exposure duration affect larval lampreys, but there was no previously published information to inform our selection of test parameters. Thus, we used a two phased approach where Phase 1 was a pre-test to help us refine appropriate treatments for Phase 2. In Phase 1 of the study, we used a constant overburden depth (50 cm) and exposure duration (24 h) to compare four sediment treatments that varied the initial burrowing sediment and the overburden sediment: fine-fine, fine-sand, sand-fine, sand-sand. In all four treatments, most lampreys vertically migrated through the overburden and were recovered in the uppermost tube section 24 h after overburden was added. There were no lamprey mortalities, few injuries, and little evidence of sublethal effects of overburden stress based on burrowing performance tests. Lampreys moved the most in the fine-sand and fine-fine treatments, so they were used for continued testing. In Phase 2 we doubled the overburden depth to 100 cm and tested extended exposure durations (1 to 4 d), and based on those results, added tests of shorter durations (1 to 8 h). Since both treatments used fine sediment for initial borrowing, these tests effectively compared fine and sand sediments as overburden. Overall for Phase 2, there were no lamprey mortalities, little evidence of sublethal effects, and 6.4% of the treatment fish were injured. Most of the injuries were mild abrasions, but some fish had serious damage such as a large gash or nearly complete bisection. We estimate that the serious injuries occurred as tube sections were separated during sampling, but the cause of the minor injuries could not be clearly ascribed to overburden stress or sampling activity. Lampreys moved to the upper sections of the tubes through 100 cm of fine and sand overburden within 1 d. Lamprey position was comparable among the 1-4 d exposures, although position was more variable at 1 d compared to 4 d. Tests of exposures less than 24 h showed that fewer than 40% of lampreys completed vertical migrations to the top of the tube after 4 h, and after 8 h the uppermost tube section contained 33% of lampreys in the sand treatment and 44% of lampreys in the fine treatment. We concluded that the minimum time needed for most lampreys to complete vertical migrations through 100 cm of overburden lies somewhere between 8 and 24 h. Lamprey size influenced recovery position in 4 and 8 h exposures to sand overburden, but not for other tests. The mean size of fish near the bottom of the tubes was significantly larger than the size of fish near the top of the tubes. To our knowledge this was the first formal study to evaluate lamprey responses to overburden. Although our test systems were imperfect simulations of natural conditions, and several questions would benefit from additional research, our findings can inform guidelines on sediment handling practices to limit negative impacts to larval lampreys.

Report↗

USGS2023

Influence of lamprey rearing type on measures of performance

Declines in populations of Pacific Lamprey (Entosphenus tridentatus) have raised concerns by the Columbia River tribes, who then initiated efforts to protect and restore them throughout their historical range. The Columbia River Inter-Tribal Fish Commission (CRITFC) devised a restoration plan for lamprey in the Columbia River Basin which highlights the significance of lamprey to the tribes and recommends conservation actions. The plan calls for the development of artificial propagation (AP) protocols to provide fish for research (e.g., downstream passage studies) and restoration activities (e.g., supplemental releases into streams/rivers). The ideal outcome of these efforts would be cultured fish that are comparable to the corresponding wild fish, and efforts are underway to conduct such evaluations in larval and juvenile lamprey. The CRITFC lamprey restoration plan lists improving dam passage for juvenile and larval lamprey as a high priority action. Active telemetry techniques have not been an option until recently, when a prototype micro acoustic transmitter was designed for small, elongate fishes like lamprey and eels. Passage survival studies of juvenile and larval lamprey using acoustic telemetry are now possible but are challenged with the limited availability of research animals. The use of AP fish would facilitate passage survival studies, under the assumption that AP juvenile and larval lamprey perform and survive comparably to the wild lamprey they are intended to represent. The current study was enacted to add to the growing knowledge of how reliably AP lamprey can be used as surrogates for wild lamprey. Study objectives were to: 1) compare the swimming ability of AP and wild juvenile lamprey implanted with the prototype micro acoustic transmitter and 2) compare the performance of AP and wild larval lamprey by evaluating night activity levels, burrowing ability, and photokinetic response to tail illumination over a period of 5-months in a culture setting. Evaluations of juvenile lamprey sustained swimming performance did not reveal any differences between tagged and untagged lamprey of AP or wild origin. We standardized the stage of transformation for all tested lamprey to minimize variation. Our tests were constrained by limited access to juvenile lamprey, so significant differences between rearing types may have gone undetected. More information on how rearing type influences other lamprey life stages and swimming performance will add to the growing knowledge on how reliably AP lamprey can serve as surrogates for wild lamprey. We compared AP and wild larval lamprey using three performance metrics, both shortly after they arrived at our laboratory and through a 5-month study period. Within the AP and wild test groups, we divided lamprey into small (30-70 mm total length) and large (80-120 mm total length) size categories, forming four test groups. Each of the test groups were comprised of 25 lamprey and were held in separate tanks. These tanks were the source of test fish for all performance testing. Our results for 2 of 3 of the performance metrics showed no differences between rearing types, and we found limited evidence to suggest that duration in a culture setting changed performance. Night activity levels were low for all test groups. Burrowing times were significantly different by rearing type, with wild lamprey burrowing faster than AP lamprey, in both the small and large size categories. These significant differences in rearing type could be a concern for use of AP lamprey for restoration or research needs, but they may not be biologically meaningful. Both AP and wild lamprey completed burrowing in median times of less than 1 min, which minimizes concerns about predation risk. Additional opportunities to evaluate burrowing performance of AP and wild larval lamprey would be helpful to inform future planned uses of AP lamprey. Finally, our evaluations of photokinetic response to tail illumination revealed similar proportions of AP and wild larvae moving in response to illumination, and no significant differences in response time between the groups. The wild lamprey, however, consistently had faster (but not significantly) response times than AP fish. This finding supports the significantly faster burrowing times we observed for wild lamprey compared to AP fish. Taken together, these lines of evidence raise some concerns for the ability of AP lamprey to serve as defensible surrogates for wild lamprey because the ability to reliably burrow is so critical for larvae. Burrowing performance and photokinetic response to tail illumination were both easy to measure and will be valuable metrics for evaluating rearing types in future studies.

Report↗

USGS2019

Effectiveness of fish screens in protecting lamprey (Entosphenus and Lampetra spp.) ammocoetes—Pilot testing of variable screen angle

Thousands of screened water diversions throughout the Columbia River Basin of the Pacific Northwest are sources of entrainment (unintended diversion into an unsafe passage route), injury, and mortality for a range of fish species and screening criteria have been developed to reduce and mitigate these effects. Large knowledge gaps exist concerning the potential effects of these screens on juvenile and larval lampreys ( Entosphenus and Lampetra spp. ) that may be particularly vulnerable to screening effects owing to their small size, unique morphology, and poor swimming performance. The few studies that have evaluated screen impacts for lampreys have compared common screen materials in a laboratory setting using a large, recirculating flume, and have reported that screen size and material influence the risk of entrainment. We compared entrainment rate, impingement rate and duration, injury rate, and delayed (24-hour) mortality of larval lamprey (ammocoetes) exposed to two screen angles. A 20-degree screen was tested because it is a common configuration, and a 12-degree screen was selected to represent a screen more parallel to flow than the 20-degree screen. We included juvenile rainbow trout ( Oncorhynchus mykiss ) in tests for both screen angles so that any screen interaction improvements observed for lamprey could be considered in light of their effect on salmonids ( Oncorhynchus spp. ). Study fish were released singly into the flume at two locations: near-screen (SCR) releases at about 30 centimeters upstream of the screen and mid-channel (MID) releases at about 1.4 meters upstream of the screen. We completed 120 screen trials with ammocoetes and 117 screen trials with juvenile tout during April–May 2018. Ammocoetes had short mean trial durations (less than 30 seconds) and were most frequently bypassed. Over one-half of the ammocoetes briefly (for less than 1 second) contacted the screen. Rates of screen contact were similar between the two screen angles, but higher for SCR releases (about 83–90 percent) than for MID releases (about 28–44 percent). Screen impingements were not common (8.3 percent of ammocoetes) and did not result in significant injury or delayed mortality. The final logistic regression model showed that screen angle and release location did not significantly affect whether ammocoetes were bypassed. The size of the lamprey, expressed as mass or length, was the only significant predictor of fate. We noted an estimated 4.7-percent increase in the odds of being bypassed for every 1-milligram increase in ammocoete mass and a 49-percent increase in the odds of being bypassed for every 1-millimeter increase in length. Trout did not experience negative effects with the 12-degree screen; they had short mean trial durations (less than 40 seconds) and limited contact with the screens (11.1 percent of trout), were most commonly bypassed, and none were entrained. Screen angle and release location were not significant drivers of fate for trout. The 12-degree and 20-degree screens performed comparably for both lamprey and trout and effectively bypassed these fishes. Some metrics showed advantages for the 12-degree screen, suggesting that screens installed more parallel to flow might warrant further testing.

Columbia River Basin↗