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DOE OSTI2015

Evaluating the Potential for Marine and Hydrokinetic Devices to Act as Artificial Reefs or Fish Aggregating Devices. Based on Analysis of Surrogates in Tropical, Subtropical, and Temperate U.S. West Coast and Hawaiian Coastal Waters

Wave energy converters (WECs) and tidal energy converters (TECs) are only beginning to be deployed along the U.S. West Coast and in Hawai‘i, and a better understanding of their ecological effects on fish, particularly on special-status fish (e.g., threatened and endangered) is needed to facilitate project design and environmental permitting. The structures of WECs and TECs placed on to the seabed, such as anchors and foundations, may function as artificial reefs that attract reef-associated fishes, while the midwater and surface structures, such as mooring lines, buoys, and wave or tidal power devices, may function as fish aggregating devices (FADs), forming the nuclei for groups of fishes. Little is known about the potential for WECs and TECs to function as artificial reefs and FADs in coastal waters of the U.S. West Coast and Hawai‘i. We evaluated these potential ecological interactions by reviewing relevant information about fish associations with surrogate structures, such as artificial reefs, natural reefs, kelps, floating debris, oil and gas platforms, marine debris, anchored FADs deployed to enhance fishing opportunities, net-cages used for mariculture, and piers and docks. Based on our review, we postulate that the structures of WECs and TECs placed on or near the seabed in coastal waters of the U.S. West Coast and Hawai‘i likely will function as small-scale artificial reefs and attract potentially high densities of reef-associated fishes (including special-status rockfish species [Sebastes spp.] along the mainland), and that the midwater and surface structures of WECs placed in the tropical waters of Hawai‘i likely will function as de facto FADs with species assemblages varying by distance from shore and deployment depth. Along the U.S. West Coast, frequent associations with midwater and surface structures may be less likely: juvenile, semipelagic, kelp-associated rockfishes may occur at midwater and surface structures of WECs in coastal waters of southern California to Washington, and occasional, seasonal, or transitory associations of coastal pelagic fishes such as jack mackerel (Trachurus symmetricus) may also occur at WECs in these waters. Importantly, our review indicated that negative effects of WEC structures on special-status fish species, such as increased predation of juvenile salmonids or rockfishes, are not likely. In addition, WECs installed in coastal California, especially in southern California waters, have the potential to attract high densities of reef-associated fishes and may even contribute to rockfish productivity, if fish respond to the WECs similarly to oil and gas platforms, which have some of the highest secondary production per unit area of seafloor of any marine habitat studied globally (Claisse et al. 2014). We encountered some information gaps, owing to the paucity or lack, in key locations, of comparable surrogate structures in which fish assemblages and ecological interactions were studied. TECs are most likely to be used in the Puget Sound area, but suitable surrogates are lacking there. However, in similarly cold-temperate waters of Europe and Maine, benthopelagic fish occurred around tidal turbines during lower tidal velocities, and this type of interaction may be expected by similar species at TECs in Puget Sound. To address information gaps in the near term, such as whether WECs would function as FADs in temperate waters, studies of navigation buoys using hydroacoustics are recommended.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2017

Triton: Igiugig Fish Video Analysis (Project Report)

This document summarizes the analysis of video data collected around the Ocean Renewable Power Company’s RivGen® device in the Kvichak River during July and August 2015. Human (manual) analysis of the data was undertaken and used to develop automated algorithms to detect fish in the frames and describe interaction behavior. In addition, a web application, EyeSea, was developed to combine manual and automated processing, so that ultimately the automated algorithms could be used to identify where human analysis was needed (i.e., when fish are present in video frames). The aim of the project was to develop algorithms that could identify video frames with fish present that could then be used to enable faster manual analysis. However, the project has also identified recommendations for future data collection, and research that could help analysis and interpretation. The manual analysis started to look at all data from the start of the deployment; this was to ensure rare events were seen, and initially focused on night-time data when more fish were present. This process highlighted the amount of time taken to identify fish, and ultimately only 42.33 hours of video were reviewed due to the time-consuming analysis. The data were classified as ‘Fish’, when the reviewer was confident it was a fish, and ‘Maybe’ fish, when it was difficult to distinguish. This was based on the movement, shape and color characteristics. ‘Fish’ were further classified as ‘adult’, ‘juvenile’, or ‘unidentifiable’. Behavioral attributes were noted, which were broadly divided into passive and avoidance activities. In over 42 hours data, there were only 20 potential contact interactions, of which 3 were ‘Maybe’ classifications, 12 were juveniles and 5 were adults; on only one occasion was an actual contact confirmed, and this was an adult fish with the camera, not the turbine itself. This also highlights the difficulties associated with confirming a strike or collision event as occurring or being a near-miss. More interactions were detected at night; this was probably biased by nighttime artificial light use, which may have attracted fish, but also could have increased detection probability as the light is reflected from the fish itself. For the algorithm development, background subtraction, optical flow, and deep learning techniques were considered. The deep learning approach was determined as needing too much training data for this application, and therefore was not continued. The optical flow analysis was considered promising, but did not give immediate results, so would need further investigation. Therefore, background subtraction was the main focus. Three methods of background subtraction were tried: Robust Principal Components Analysis (RPCA), Gaussian Mixture Model (GMM) and Video Background Extraction(ViBE). A classification technique was then applied to the foreground images to determine fish presence. Using this combination, it was found that fish could be accurately detected when occupying more pixels (>200 pixels, 98.2% correct; 100-200 pixels, 99.6% correct; 5-100 pixels, 85.4% correct; 2-5 pixels, 66.3% correct). In parallel, EyeSea was developed to convert the video data to a usable form and to enable manual and automated analysis of the data that would have a standardized output. Recommendations for further research, and standardized methods for data collection are given.

13 HYDRO ENERGY↗

DOE OSTI2022

Capabilities of an Acoustic Camera to Inform Fish Collision Risk with Current Energy Converter Turbines

A diversified energy portfolio may include marine energy in the form of current energy converters (CECs) such as tidal or in-river turbines. New technology development in the research stage typically requires monitoring for environmental effects. A significant environmental effect of concern for CECs is the risk of moving parts (e.g., turbine blades) colliding with animals such as fishes. CECs are installed in energetic locations in which it is difficult to operate sensors to fulfill monitoring requirements for informing collision risk. Collecting data (i.e., about blade strikes or near-misses) that inform interactions of fishes with CECs is usually attempted using active acoustic sensors or video cameras (VCs). Limitations of low-light conditions or water turbidity that preclude effective use of VCs are overcome by using high-resolution multibeam echosounders (or acoustic cameras (ACs)). We used an AC at two sites to test its ability to detect artificial and real fish targets and determine if strike, near-miss, and near-field behavior could be observed. Interactions with fish and artificial targets with turbines have been documented but strike confirmation with an AC is novel. The first site was in a tidal estuary with a 25 kW turbine and water clarity sufficient to allow VC data to be collected concurrently with AC data showing turbine blade strike on tethered artificial fish targets. The second site was a turbid, debris-laden river with a 5 kW turbine where only AC data were collected due to high water turbidity. Data collection at the second site coincided with downstream Pacific salmon (Oncorhynchus spp.) smolt migration. Physical fish capture downstream of the turbine was performed with an incline plane trap (IPT) to provide context for the AC observations, by comparing fish catches. Discrimination between debris and fishes in the AC data was not possible, because active movement of fishes was not discernable. Nineteen fishes were released upstream of the turbine to provide known times of possible fish/turbine interactions, but detection was difficult to confirm in the AC data. ACs have been used extensively in past studies to count large migratory fish such as Pacific salmon, but their application for small fish targets has been limited. The results from these two field campaigns demonstrate the ability of ACs to detect targets in turbid water and observe blade strikes, as well as their limitations such as the difficulty of distinguishing small fishes from debris in a high-energy turbid river. Recommendations are presented for future applications associated with CEC device testing.

16 TIDAL AND WAVE POWER↗

DOE OSTI2019

Evaluation of a fish-friendly self-cleaning horizontal irrigation screen using autonomous sensors

Irrigation modernisation is booming globally because of the increasing demand on water and food. However, irrigation infrastructures can injure fish or entrain them into irrigation water. Screening is an effective method to mitigate fish entrainment. In this study, two autonomous sensor devices, developed and manufactured at Pacific Northwest National Laboratory (Sensor Fish and its miniaturised version, Sensor Fish Mini) were deployed to evaluate the physical and fish passage conditions of a unique horizontal, flat-plate fish and debris screen (known as the Farmers Screen) that was installed in Oregon, USA. Only 1 of the 27 Sensor Fish Mini releases had a severe acceleration event, whereas 0 of the 37 Sensor Fish releases had severe events. The rates of severe events and amplitudes of accelerations at the Farmers Screen were significantly lower than those at other hydraulic structures, including a fish-friendly surface weir that recorded nearly 100% fish survival. Overall, the results indicated that the Farmers Screens can provide safe downstream passage for fish at irrigation diversions. This study also demonstrated that the Sensor Fish technology, including Sensor Fish Mini, is a suitable technology for evaluating irrigation structures and providing important information for the development of sustainable irrigation.

47 OTHER INSTRUMENTATION↗

DOE OSTI2017

Multi-scale temporal patterns in fish presence in a high-velocity tidal channel

The natural variation of fish presence in high-velocity tidal channels is not well understood. A better understanding of fish use of these areas would aid in predicting fish interactions with marine hydrokinetic (MHK) devices, the effects of which are uncertain but of high concern. To characterize the patterns in fish presence at a tidal energy site in Cobscook Bay, Maine, we examined two years of hydroacoustic data continuously collected at the proposed depth of an MHK turbine with a bottom-mounted, side-looking echosounder. The maximum number of fish counted per hour ranged from hundreds in the early spring to over 1,000 in the fall. Counts varied greatly with tidal and diel cycles in a seasonally changing relationship, likely linked to the seasonally changing fish community of the bay. In the winter and spring, higher hourly counts were generally confined to ebb tides and low slack tides near sunrise and sunset. In summer and fall of each year, the highest fish counts shifted to night and occurred during ebb, low slack, and flood tides. Fish counts were not linked to current speed, and did not decrease as current speed increased, contrary to observations at other tidal power sites. As fish counts may be proportional to the encounter rate of fish with an MHK turbine at the same depth, highly variable counts indicate that the risk to fish is similarly variable. The links between fish presence and environmental cycles at this site will likely be present at other locations with similar environmental forcing, making these observations useful in predicting potential fish interactions at tidal energy sites worldwide.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2020

Evaluation of Foster Dam Juvenile Fish Passage, 2018 (Final Report)

This report presents the results of a fish passage study conducted by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers Portland District (USACE) at Foster Dam (herein, Foster) during the spring (March–June) and fall (October–December) of 2018. The goal of this study was to provide biologists, engineers, resource managers, and regional decision-makers with information about passage of juvenile Chinook salmon and juvenile steelhead (or appropriate surrogates) through specific routes at Foster. The results of this study are intended to help facilitate decision-making regarding long-term measures for enhancing salmonid passage at Foster. Radio telemetry (RT) methods were instituted at low winter reservoir forebay elevation (low pool, 613 ft mean sea level (msl); spring 2018 and fall 2018) and high summer reservoir forebay elevation (high pool, 635 ft msl; late spring and early summer 2018) to accomplish the following objectives: I. Estimate the following passage metrics under typical operations (i.e., baseline conditions): a. Overall dam-passage survival and survival specific to each route of dam passage, calculated using two different methods: i. Cormack-Jolly-Seber (CJS) estimate: Probability of survival from dam passage to detection at the Primary Array, 19 river kilometers (rkm) downstream of Foster. ii. Virtual Release/Dead Fish Correction (ViRDCt) estimate: Corrects the bias that occurs from misidentifying fish that did not survive dam-passage as alive at the tailrace Egress Array, allowing an estimate of survival from dam passage to this array, 2.5 rkm downstream of Foster. b. Route distribution (passage proportions by route; also known as “passage efficiencies”). c. Efficiency metrics i. Dam-passage efficiency (DPE), the proportion of total fish passing the dam relative to the number of total fish detected in the near forebay of the dam and therefore available to pass. ii. Fish passage efficiency (FPE), the proportion of fish passing via a non-turbine route, relative to the number of total fish in the near forebay and available to pass. iii. Fish weir efficiency (FWE) and spill bay efficiency (SBE), the proportion of fish passing the weir or spill bays, respectively, relative to the total number of fish passing the dam. d. Reservoir residency time (time elapsed between release into reservoir and dam passage) and travel times through the system. II. Estimate efficiency and effectiveness of the new fish weir, compared to the turbines and the spillway. III. Under alternative operations, compare passage through each route (turbines, weir, spillway) using a block/treatment (on/off) design similar to the 2015 and 2016 studies. IV. Estimate efficiency of the new fish weir operating at a low level of discharge (< 500 cfs) and a high level of discharge (= 500 cfs), as well as dam passage survival at each weir discharge level. V. Evaluate survival and behavior of hatchery summer steelhead to wild surrogate winter steelhead for potential use of summer steelhead as a surrogate species winter steelhead. VI. Evaluate juvenile passage rates in the auxiliary water supply (AWS), forebay water supply (FWS), and hatchery water supply (HWS).

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2020

The skin microbiome of elasmobranchs follows phylosymbiosis, but in teleost fishes, the microbiomes converge

Background: The vertebrate clade diverged into Chondrichthyes (sharks, rays, and chimeras) and Osteichthyes fishes (bony fishes) approximately 420 mya, with each group accumulating vast anatomical and physiological differences, including skin properties. The skin of Chondrichthyes fishes is covered in dermal denticles, whereas Osteichthyes fishes are covered in scales and are mucous rich. The divergence time among these two fish groups is hypothesized to result in predictable variation among symbionts. Here, using shotgun metagenomics, we test if patterns of diversity in the skin surface microbiome across the two fish clades match predictions made by phylosymbiosis theory. In this work, we hypothesize (1) the skin microbiome will be host and clade-specific, (2) evolutionary difference in elasmobranch and teleost will correspond with a concomitant increase in host-microbiome dissimilarity, and (3) the skin structure of the two groups will affect the taxonomic and functional composition of the microbiomes. Results: We show that the taxonomic and functional composition of the microbiomes is host-specific. Teleost fish had lower average microbiome within clade similarity compared to among clade comparison, but their composition is not different among clade in a null based model. Elasmobranch’s average similarity within clade was not different than across clade and not different in a null based model of comparison. In the comparison of host distance with microbiome distance, we found that the taxonomic composition of the microbiome was related to host distance for the elasmobranchs, but not the teleost fishes. In comparison, the gene function composition was not related to the host-organism distance for elasmobranchs but was negatively correlated with host distance for teleost fishes. Conclusion: Our results show the patterns of phylosymbiosis are not consistent across both fish clades, with the elasmobranchs showing phylosymbiosis, while the teleost fish are not. The discrepancy may be linked to alternative processes underpinning microbiome assemblage, including possible historical host-microbiome evolution of the elasmobranchs and convergent evolution in the teleost which filter specific microbial groups. Our comparison of the microbiomes among fishes represents an investigation into the microbial relationships of the oldest divergence of extant vertebrate hosts and reveals that microbial relationships are not consistent across evolutionary timescales.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2014

Assessing ecological risks to the fish community from residual coal fly ash in Watts Bar Reservoir, Tennessee

For this research, extensive site-specific biological and environmental data were collected to support an evaluation of risks to the fish community in Watts Bar Reservoir from residual ash from the December 2008 Tennessee Valley Authority (TVA) Kingston ash release. This paper describes the approach used and results of the risk assessment for the fish community, which consists of multiple measurement endpoints (measures of exposure and effects) for fish. The lines of evidence included 1) comparing postspill annual fish community assessments with nearby prespill data and data from other TVA reservoirs, 2) evaluating possible effects of exposures of fish eggs and larval fish to ash in controlled laboratory toxicity tests, 3) evaluating reproductive competence of field-exposed fish, 4) assessing individual fish health through physical examination, histopathology, and blood chemistry, 5) comparing fish tissue concentrations with literature-based critical body residues, and 6) comparing concentrations of ash-related contaminants in surface waters with US Environmental Protection Agency's (USEPA) Ambient Water Quality Standards for Fish and Aquatic Life. These measurement endpoints were treated as independent lines of evidence that were integrated into an overall weight-of-evidence estimate of risk to the fish community. Collectively, the data and analysis presented here indicate that ash and ash-related constituents pose negligible risks to the fish communities in Watts Bar Reservoir. This conclusion contradicts the predictions by some researchers immediately following the ash release of devastating effects on the aquatic ecology of Watts Bar Reservoir. The information presented in this article reaffirms the wisdom of carefully evaluating the evidence before predicting probable ecological effects of a major event such as the TVA Kingston ash release. Lastly, this study demonstrates that a thorough and detailed investigation using multiple measurement endpoints is needed to properly evaluate ecological effects.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2020

A global analysis on the systemic effects of antibiotics in cultured fish and their potential human health risk: a review

Abstract The rearing of fish in intensive systems reduces their immunity leading to eruption of diseases, consequently prompting the use of antibiotics. Antibiotics are currently used in cultured fish globally to treat/prevent diseases. On the one hand, antibiotics used in aquaculture help to improve fish health by killing or inhibiting pathogenic bacteria proliferation. However, on the other hand, they cause multiple side effects. To date, information on systemic effects of antibiotics in cultured fish is scattered and their potential human health risk remains elusive. This review critically analyses and discusses the available information in the literature on the positive and negative effects of antibiotics in cultured fish and their potential human health risk via fish consumption. The review found 44 different antibiotics dominated by oxytetracycline were studied in various fish species worldwide. Antibiotics used in global aquaculture either decrease or increase fish growth and survival rates. They induce oxidative stress, which affect antioxidant and detoxification responses and cause host–microbiota dysbiosis. These changes compromise the fish immunity system, which ultimately lead to cellular damage. The toxicities generated inhibit the fish aerobic glycolysis, suppress lipogenesis and fatty acid β‐oxidation while increase energy demand by initiating gluconeogenesis and anaerobic glycolysis. Consumption of fish treated with antibiotics causes human health risk. Future studies are required on agents to restore dysfunctions induced by antibiotics in cultured fish, while attempts to limit their utilisation in aquaculture production are underway. [Correction added on 21 November 2020, after first online publication: The abstract has been amended to clarify the scope of the review.]

Limbu, Samwel Mchele↗

DOE OSTI2021

Creation of a prototype biomimetic fish to better understand impact trauma caused by hydropower turbine blade strikes

Biomimetic model organisms could be useful surrogates for live animals in many applications if the models have sufficient biofidelity. One such application is for use in field and laboratory tests of fish mortality associated with passage through hydropower turbines. Laboratory trials suggest that blade strikes are especially injurious and often causes mortality when fish are struck by thinner blades moving at higher velocities. Dose-response relationships have been created from these data, but the exact relationship between fish mortality and the actual forces enacted on fish during simulated blade strike testing remains unknown. Here, we describe the methods used to create a prototype biomimetic model fish composed of ballistic gelatin and covered with a surrogate skin to better approximate the biomechanical properties of a fish body. Frozen fish were scanned with high-fidelity laser scanners, and a 3D-printed, reusable mold was created from which to cast our gelatin model. Computed tomography scan data, imaged directly or taken from online data repositories, were also successfully used to create CAD models for use in additive manufacturing of molds. One 3-axis accelerometer was embedded into the gelatin to compare accelerometer data to dose-response data from previous laboratory research on live fish. The resulting model ( i.e. , Gelfish) had a statistically indistinguishable tissue durometer to that of real fish tissue and preliminary blade strike impact testing suggested its overall flexibility was similar to that of live fish. Gelfish was designed with biofidelity as its guiding principle and our results suggest initial experimentation was successful. Future research will include replication of initial Gelfish test results, quantitative measurement of model flexibility relative to real fish, and inclusion of surrogate skeletal structures to enhance biofidelity. Use of more sophisticated sensors would also better quantify the physical forces of blade strike impact and help determine how said forces correlate with rates of mortality observed during tests on live fish.

36 MATERIALS SCIENCE↗

DOE OSTI2024

Feasibility study for test rig assessments of fish passage conditions in a Kaplan turbine

The assessment of fish passage conditions in hydroelectric turbines consists of identifying and quantifying physical magnitudes leading to increased risks of injury of fish passing through turbines in operation. Such assessments are usually carried out either with the use of computer-based methods during design or with field testing of live fish and sensors passing through prototypes. A method in between consists of test rig experimentation, which is critical for testing fish-focused design concepts and offers the opportunity for implementing the most effective design measures for improved fish survivability. However, fish-related assessments in test rigs are not sufficiently documented for industrial applications. This work presents the main findings of an experimental campaign to quantify fish-related hydraulic magnitudes in a physical model of a Kaplan turbine in a commercial test rig. Two operating conditions were tested by releasing miniaturized autonomous sensor devices (termed Sensor Fish Mini) at the turbine intake flow, passing them through the runner in motion and recovering them at the draft tube exit. During passage, time series of acceleration, absolute pressure and rotational velocity were recorded. The recordings were then interpreted to determine the magnitude and likely location of hydraulic stressors hazardous to fish. The statistical tests on the reported measurements indicated that low pressure, collisions on the runner and rotations in the draft tube were not different between the two tested operating points. On the other hand, pressure drop and collision rates on the distributor differed considerably as a function of net head. The outcomes of this investigation showed that test rig evaluations of fish-related properties with Sensor Fish Mini can contribute to an evidence-based development of turbine geometries designed for providing safer passage conditions. Future work will investigate the scaling of test rig measurements to hydraulically equivalent magnitudes in the prototype and their biological consequences.

13 HYDRO ENERGY↗

DOE OSTI2015

Hydrologic filtering of fish life history strategies across the United States: implications for stream flow alteration

Lotic fish have developed life history strategies adapted to the natural variation in stream flow regimes. The natural timing, duration, and magnitude of flow events has contributed to the diversity, production, and composition of fish assemblages over time. Studies evaluating the role of hydrology in structuring fish assemblages have been more common at the local or regional scale with very few studies conducted at the continental scale. Furthermore, quantitative linkages between natural hydrologic patterns and fish assemblages are rarely used to make predictions of ecological consequences of hydrologic alterations. We ask two questions: (1) what is the relative role of hydrology in structuring fish assemblages at large scales? and (2) can relationships between fish assemblages and natural hydrology be utilized to predict fish assemblage responses to hydrologic disturbance? We developed models to relate fish life histories and reproductive strategies to landscape and hydrologic variables separately and then combined. Models were then used to predict the ecological consequences of altered hydrology due to dam regulation. Although hydrology plays a considerable role in structuring fish assemblages, the performance of models using only hydrologic variables was lower than that of models constructed using landscape variables. Isolating the relative importance of hydrology in structuring fish assemblages at the continental scale is difficult since hydrology is interrelated to many landscape factors. By applying models to dam-regulated hydrologic data, we observed some consistent predicted responses in fish life history strategies and modes of reproduction. In agreement with existing literature, equilibrium strategists are predicted to increase following dam regulation, whereas opportunistic and periodic species are predicted to decrease. In addition, dam regulation favors the selection of reproductive strategies with extended spawning seasons and preference for stable conditions.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2018

What’s hot about mercury? Examining the influence of climate on mercury levels in Ontario top predator fishes

Highlights: • Fish mercury levels have recently increased in many Ontario watersheds. • Weather, climate drivers, and emissions are contributing to changes in fish mercury. • Changes in climate may be an important driver of Ontario fish mercury levels. • Higher mercury levels in walleye and largemouth bass are related to climate drivers. • Higher precipitation contributed to higher mercury levels in smallmouth bass. Mercury (Hg) levels in Ontario top predator fishes have been increasing in recent decades. These increases may be a result of many additive factors, including global climate change. Only recently has research been conducted on how climate change may impact Hg levels in freshwater fishes at large-scales. We examined the relationship between Hg trends and (1) local weather, (2) large-scale climate drivers, and (3) anthropogenic Hg emissions, in native cool water (walleye and northern pike) and warm water (smallmouth bass and largemouth bass) predatory fishes in Ontario, Canada, for historical (1970–1992) and recent (1993–2014) time periods. For each fish species studied, > 25% of Ontario's secondary watersheds shifted from historically declining to recently increasing fish Hg trends, and ≥ 50% of watersheds experienced increasing trends between 1993 and 2014. Recent fish Hg increased at up to 0.20 µg/g/decade; which were significant (p < 0.05) for walleye, northern pike and smallmouth bass. Multiple linear regressions revealed a complex interplay of local weather, large-scale climate drivers, and anthropogenic Hg emissions influencing fish Hg levels. Recent Hg levels for walleye and largemouth bass increased with changes in global climate drivers, while higher precipitation influenced smallmouth bass Hg levels the most. Walleye Hg levels increased during the positive phases of global climate drivers, reflecting the local influence of local temperatures and precipitation indirectly. Differentiating the effects of climate-related parameters and emissions is increasingly crucial to assess how changing multiple environmental stressors may impact health of wildlife and humans consuming fish.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2023

Observing fish interactions with marine energy turbines using acoustic cameras

Abstract Marine current energy converters such as tidal and riverine turbines have the potential to provide reliable, clean power. The risk of collision of fishes with marine energy turbines is not yet well understood, in part due to the challenges associated with observing fish at turbine sites. Turbidity and light availability can limit the effectiveness of optical sensors like video cameras, motivating the use of acoustic cameras for this task. However, challenges persist in collecting and interpreting data acquired from acoustic cameras. Given the limited number of turbine deployments to date, it is prudent to draw on the application of acoustic cameras to monitor fish in other scenarios. This article synthesizes their use for other fisheries applications to inform best practices and set realistic expectations for the results of acoustic camera monitoring at turbine sites. We discuss six key tasks performed with acoustic cameras: detecting objects, identifying objects as fish, counting fish, measuring fish, classifying fish taxonomically and analysing fish behavior. Specific challenges to monitoring fish at turbine sites are discussed. This article is intended to serve as a reference for researchers, regulators and marine energy developers on effective use of acoustic cameras to monitor fish at turbine sites. The studies detailed in this article provide evidence that, in some scenarios, acoustic cameras can be used to inform the risk of fish collision with marine energy turbines but doing so requires careful study design and data processing.

Cotter, Emma↗

DOE OSTI2015

Impacts of electromagnetic fields associated with marine and hydrokinetic surrogate technologies on fish movements and behaviors.

Marine and hydrokinetic energy (MHK) and offshore wind devices are being developed and deployed in U.S. and international waters. Electric current flowing through subsea transmission cables associated with these devices will generate electromagnetic fields (EMF), which may interact with, and potentially impact, marine fishes. Some marine fishes can detect electric and/or magnetic fields and use them to navigate, orientate, and sense prey, mates and predators. Over the past five years there have been multiple comprehensive reviews and studies evaluating the potential vulnerability of marine fishes to EMF produced by MHK devices. Most documented effects involve sub-lethal behavioral responses of individual fish when in close proximity to EMF (e.g., fish being repelled by or attracted to fields). These reviews reach conclusions that the current state of research on this topic is still in its infancy and evaluations of potential impacts are associated with great uncertainty. A variety of MHK technologies are likely to be considered for deployment offshore of the Hawaiian Islands, and there is a need to be able to better predict and assess potential associated environmental impacts. The goal of this study was to provide a complementary piece to these previous reviews (e.g., Normandeau et al. 2011) by focusing on marine fish species in the Hawaii region. We compiled the relevant available information, then prioritized fish species as candidates for various paths of future research. To address this, we first developed a list of Hawaii Region Focal Species, which included fishes that are more likely to be sensitive to EMF. We then compiled species-specific information available in the literature on their sensitivity to EMF, as well as life history, movement and habitat use information that could inform an analysis of their likelihood of encountering EMF from subsea cables associated with MHK devices. Studies have only documented EMF sensitivity in 11 of the marine fish species in this region. There was also relatively little detailed information on fish movement and habitat use patterns for most of the focal species. Our last objective was to develop recommendations for research needs to close the important knowledge gaps. We describe species-independent baseline research that primarily consists of in situ quantification of EMF generated by MHK devices and undersea cables that can occur as pilot and commercial scale MHK devices are deployed in Hawaii. Then we propose a simple approach for prioritizing Hawaii Region Focal Species (ranked relative to each other) as candidates in multiple related research paths. The prioritization approach incorporates EMF sensitivity information with the likelihood of interacting with EMF generated undersea transmission cables associated with MHK devices. Finally, we discuss the types of research needed to help fill gaps in the scientific knowledge base for this region. These involve studies to better define species-specific EMF sensitivity thresholds under various environmental conditions, studies of life history, movement and habitat use patterns to improve our understanding of the likelihood and frequency fishes may be in the vicinity of EMF generated by subsea transmission cables, and studies of the potential for related population, community or ecosystem impacts. Many of these studies can and should occur opportunistically as pilot and commercial scale MHK devices are deployed in Hawaii.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2026

Stakeholder Questionnaire on Fish Passage Facilities at U.S. Hydropower Developments

To mitigate the environmental impacts of hydropower dams on fish populations in rivers, fish passage infrastructure may be required by regulatory authorities or recommended by state or federal agencies to allow migratory fish to pass hydropower barriers and complete their life histories. However, information on the location, types, and characteristics of fish passage infrastructure is incomplete at the national scale. This lack of information limits understanding of current fish passage capabilities and hinders efforts to anticipate future passage requirements during project licensing or relicensing. To address this knowledge gap, researchers at Oak Ridge National Laboratory partnered with federal agency and industry stakeholders to create the first national-scale database of fish passage infrastructure at U.S. hydropower developments. As part of this effort, a stakeholder questionnaire was created and deployed to solicit information on fish passage infrastructure, including engineering characteristics, operational schedules, targeted species, and costs. This online questionnaire was designed to allow respondents to provide highly detailed information regarding fish passage capabilities at U.S. hydropower developments as efficiently as possible. The questionnaire improved database coverage and accuracy by providing valuable development- or passage-specific stakeholder knowledge that is not otherwise publicly available. However, questionnaire response rates were low, and stakeholders showed a preference for providing data via the spreadsheet template. This is likely because most stakeholders had high-level knowledge about fish passage existence and type at many features, and few stakeholders had highly detailed, feature-specific knowledge of fish passage infrastructure, cost, operational scheduling, and capabilities. Nonetheless, the development and deployment of the stakeholder questionnaire advanced the project in several fundamental ways, and a similar questionnaire may be valuable for future database expansion via targeted dissemination to stakeholders with confirmed knowledge of detailed fish passage information at specific hydropower projects.

13 HYDRO ENERGY↗

DOE OSTI2014

Reproductive biomarkers responses induced by xenoestrogens in the characid fish Astyanax fasciatus inhabiting a South American reservoir: An integrated field and laboratory approach

Field studies evaluating the effects of endocrine disruption chemicals (EDCs) on the fish reproduction are scarce worldwide. The goal of this study was to assess hepatic levels of vitellogenin (Vtg), zona radiata proteins (Zrp) and insulin-like growth factors (IGF-I and IGF-II), and relating them to reproductive endpoints in a wild fish population habiting a reservoir that receive domestic sewage, agricultural and industrial residues. Adult fish Astyanax fasciatus were sampled during the reproductive season in five sites from the Furnas Reservoir, Grande River, and Paraguay–Paraná basin. As a control to field data, fish were experimentally exposed via dietary intake, to oestradiol benzoate (OB) for 7 days. Fish from site with little anthropogenic interference showed hepatic levels of Vtg, Zrp and IGF-I and IGF-II similar to those from the non-treated experimental group. In sites located immediately downstream from the municipal wastewater discharges, the water total oestrogen was >120 ng/l, and male fish displayed increased Vtg and Zrp and decreased IGF-I levels similar to OB treated fish. In females, levels of Vtg, Zrp, IGF-I and IGF-II suggest an impairment of final oocyte maturation and spawning, as also detected by frequency of over-ripening, follicular atresia and fecundity. At the sites that receive agricultural and industrial residues, the water total oestrogen was <50 ng/l and females showed decreased Zrp and increased IGF-II levels associated to reduced diameter of vitellogenic follicles, indicating an inhibition of oocyte growth. Overall, the current study reports oestrogenic contamination impairing the reproduction of a wild fish from a hydroeletric reservoir and, the data contribute to improving the current knowledge on relationship between hepatic Vtg, Zrp and IGF-I and IGF-II, and reproductive endpoints in a teleost fish. In addition, our data point out novel reproductive biomarkers (IGF-I, IGF-II and over-ripening) to assessing xenoestrogenic contamination in freshwater ecosystems. - Highlights: • We point out novel reproductive biomarkers to assess xenoestrogenic contamination. • Field captured fish showed altered hepatic Vtg and Zrp. • Hepatic IGF-I and II levels were associated to reproductive disturbances. • Over-ripening is a better xenoestrogen biomarker than follicular atresia.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2016

Estimating the probability of fish encountering a marine hydrokinetic device

We report strong tidal currents in eastern Maine, USA, make that region attractive for tidal power development. We know very little about the effects of marine hydrokinetic (MHK) devices on fish, yet many fish species use tidal currents for movements. We used empirical data from stationary and mobile hydroacoustic surveys to examine the probability that fish would be at the depth of an MHK device and may therefore encounter it. The probability was estimated using three components: 1) probability of fish being at device-depth when the device was absent; 2) probability of fish behavior changing to avoid the device in the far-field; and 3) probability of fish being at device-depth in the near-field when the device was present. Furthermore, there were differences in probabilities of fish encountering the MHK device based on month, diel condition and tidal stage. The maximum probability of fish encountering the whole device was 0.432 (95% CI: [0.305, 0.553]), and the probability of fish encountering only device foils was 0.058 (95% CI: [0.043, 0.073]). Mobile hydroacoustics indicated that fish likely avoided the device with horizontal movement beginning 140 m away. Finally, we estimated the encounter probability for one device, but results can be applied to arrays, which may have bay-wide implications.

16 TIDAL AND WAVE POWER↗