November 11, 2021
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Introducing Triton 3.0: Researching Stressor/Receptor Interactions

Graphic of Triton 3.0 projects

As the Triton Initiative moves into its sixth year of marine energy environmental monitoring research, we are delighted to announce Triton 3.0, an assembly of projects seeking to advance the mission of removing barriers to installing marine energy devices. The Department of Energy Water Power Technologies Office’s Triton Initiative works to understand the potential environmental impacts of marine energy systems to inform permitting of deployments of this emerging renewable energy technology in U.S. waters. Triton 3.0 is all about researching stressor/receptor interactions (RSRI)—how receptors such as marine mammals, fish, or habitats interact with potential stressors or parts of a marine energy device or system that may stress or harm the marine environment. With Triton 3.0’s new projects, the team will conduct RSRI studies, such as exploring ways to streamline data collection and processing from collision risk monitoring technologies and integrated sensors that alert and measure potential interactions between marine animals and devices. These studies help build knowledge around animal behavior in the presence of dynamic marine energy technologies and help inform mitigation solutions for protecting the ocean’s vulnerable residents. 

Each of the leads for Triton’s next generation of projects shares a sneak peek of their new research and how they will contribute to expanding the pool of knowledge around the environmental effects of marine energy systems.  

Joe Haxel profile photo

Measuring Acoustic Particle Motion  

I’m Joe Haxel, the principal investigator for the Triton Initiative and a researcher interested in the technology and science of measuring and characterizing underwater noise around marine energy systems. For Triton 3.0, I am leading a task focused on measuring the particle motion component of acoustic (sound) energy generated by operational marine energy devices, namely turbines and wave energy converters. Sound waves in water have both pressure and particle motion components. Typically, researchers only consider the pressure amplitude of sound waves measured by hydrophones for quantifying underwater noise effects on marine species, specifically marine mammals. Meanwhile, recent studies have shown that several fish and invertebrates are more sensitive to the particle motion component of propagating acoustic energy than to pressure. To date, there is limited information from particle motion measurements in the field, creating a significant data gap for this component of acoustic disturbance to fish and invertebrates. Particle motion is gaining recognition from regulators as an essential element for monitoring the possible environmental effects of marine energy projects.  

Helping further the progress of particle motion measurements for marine-energy-related underwater noise made by Integral Consulting’s Noisespotter™, the Triton team will work with industry partners to acquire a portable, battery-operated particle motion sensor and hydrophone instrument package. This instrument will consist of one three-axis accelerometer and reference hydrophone focused on particle motion at a single point, without the advanced sound source localization capabilities of the Noisespotter™ that has several accelerometer sensors mounted on an instrument frame. Triton will also work to develop and test various flow-noise mitigation strategies (such as shields) for the instrument package to reduce any non-acoustic pressure contributions from the energetic flow around the sensors. The team will quantify flow-noise contamination in a range of environmental conditions using an acoustic doppler current profiler—a device used to measure water velocities—deployed simultaneously.  

Lastly, the project will involve working with experts on particle motion and regulators in the industry to develop best practices for field measurements and understanding effects on marine animals. These many efforts aim to build on advancements in technology for measuring particle motion and contribute to a valuable database for regulators and marine energy industry stakeholders. This is an exciting, growing area of critical research for underwater noise disturbance to marine environments where Triton will be on the cutting edge. 

Garrett Staines and Kate Buenau thumbnail photos

The Probability of Encounter Model (PoEM) 

I’m Garrett Staines, a fish biologist who focuses on fish interactions with current energy converters, like tidal and riverine turbines. In this next phase of Triton, I am leading the Probability of Encounter Model (PoEM) task. This task will work with ecological modeler Kate Buenau to create a model that informs the probability of fish encountering turbines during major movement or migration periods. Turbines are confined to certain parts of the water column, and knowing where the moving components are relative to the distribution of fish informs how likely encounters are. For example, if most fish move or migrate at the top of the water column and the turbine is close to the bottom of the water column, this might indicate interactions to be unlikely or of lower probability than if the turbine were higher up in the water.  

Close-range outcomes—like strike, near-miss, or avoidance behavior—of interactions when fish encounter turbines are challenging to observe (see Staines’ Triton Story on collision risk here). Determining the probability of fish encountering a turbine can inform if direct interaction data through field observations are needed. If deemed necessary, PoEM data could also be useful in deducing community- or population-level effects of fish encountering a turbine to understand the potential extent of risk rather than focusing on individual events. This information assists in monitoring that informs the risk of current energy converters to animals and the environment. This knowledge of risk helps reduce barriers to installing turbines and testing them.  

Molly Grear profile photo

The Strain Gauge Project  

Hi! My name is Molly Grear. I usually call myself an ocean engineer, though my training is in environmental engineering and marine biology. For Triton 3.0’s RSRI efforts, I proposed a task to mitigate the risk of collision of marine animals and tidal turbines.  

The speed of tidal turbines is changed by the speed of the flowing water, causing blades to move at a pace of up to 11 revolutions per minute. The motion of a turbine can also be changed by a controller, which can apply more or less torque to the motor and change the speed of the rotation to optimize power output. If a marine mammal approaches the turbine, the controller could theoretically also be used to slow down the blades and mitigate potential harmful collision effects. With this project, we are working to develop algorithms that allow controllers to do just that.  

Turbine blades have strain gauges in them, which monitor the structural health of the device by measuring pressure, resistance, weight, and tension as indicators of stress on the system. With this project, we are working on using these strain gauges already present in turbine blades to also detect a marine mammal collision. By adjusting these technologies, we hope a strain gauge could detect an interaction with a marine mammal or more minor differences caused by the animal’s wake, triggering the turbine to slow down to decrease the impact of a collision or even avoid interaction at all. To develop this detection ability, we plan to run scaled experiments in a flume to test strain gauge sensitivities and determine whether or not early detection is feasible.  

Collision risk has historically held back the development of tidal energy. We are thrilled to conduct research that could become a tangible collision mitigation solution that uses technology already integrated within a tidal turbine, making it a cost-effective way to protect marine life while harnessing clean energy.  

Lenaig Hemery profile photo

Crab Fine-scale Tracking (CraFT) 

My name is Lenaïg Hemery. I am a marine biologist and naturalist by training, turned benthic ecologist by practice. For the next three years, I will be leading a new RSRI task called Crab Fine-scale Tracking, or CraFT.  

Electromagnetic fields (EMFs) occur naturally in the marine environment, but marine energy devices and export cables create altered or additional sources of EMF (read the Triton Story on EMF here). Potential effects may include changes in marine animal behavior and movement in the vicinity of the EMF source, which is a concern for regulators and stakeholders responsible for the environmental permitting of marine energy development. It remains uncertain as to whether EMF can affect sensitive marine animals, especially acting as a barrier or deterrent in their natural habitats. While relatively little is known about the effects of EMFs on marine benthic invertebrates, some crabs are known to be sensitive to magnetic fields.  

Several crab species are commercially significant along the U.S. coastlines. It is essential to understand if fisheries may be affected by marine energy cables acting as a barrier to or an attractant for crustaceans. Previous experiments have used laboratory settings that exposed crabs to artificial EMFs or field experiments with crustaceans in enclosures having to cross an energized cable to go from one side of the enclosure to the other. The CraFT project intends to use acoustic tags to track the fine-scale movements of crabs around an energized cable in a field setting and at a much greater resolution than previous studies. In addition, by varying the cable's power output, we will address aspects related to dose–response effects and help establish species-specific ranges of EMF detections and thresholds to gain a better grasp on crab responses to EMFs emitted by marine energy cables. This research hopes to better understand behavioral responses to artificial EMFs and alleviate regulators' and stakeholders' concerns regarding potential harm to marine life associated with energized cables.  

Alicia Amerson profile photo

Aerial Marine Wildlife Tracking, Monitoring Technology, and Data Analysis with Machine Learning Applications  

I'm Alicia Amerson, marine biologist, Triton Initiative's project manager, and lead for Triton's aerial marine wildlife monitoring and tracking technologies study.

The ability to capture photographs and videos with unoccupied aerial vehicles (UAVs) or other aerial devices such as a tethered balloon system provides a unique opportunity for researchers to collect data about whales and other marine wildlife from the air. These aerial devices can be launched from a boat, land, or a moored buoy at sea. Benefits of aerial technologies include their adaptability and modification to host several types of sensors, including digital cameras, altimeters, and infrared or thermal imaging sensors. As part of this research, I am investigating sensor technology applications that track and monitor animals in and above the water. Data analysis is a major challenge for marine wildlife researchers, and existing machine learning programs help identify marine wildlife species. To address this challenge, I am working with data scientists at Pacific Northwest National Laboratory to train artificial intelligence programs to detect marine wildlife around marine energy test sites. One of the stressors associated with marine energy is the displacement of wildlife, which includes a change in behavior or location of an animal or the loss of habitat. To measure displacement, we will use aerial technology to detect the presence or absence of marine wildlife.

This research will be performed near the PacWave marine energy test site off the coast in Newport, Oregon. The project will first review and test various optical and infrared sensor technologies for data collection in a marine environment. Second, we will determine the best aerial technology for integrating sensors, including a review of UAVs and aerostat balloons. Additionally, we will train an artificial intelligence program to detect marine wildlife and identify species using the PacWave site. Over the past five years, Dr. Leigh Torres, PhD,our partner at Oregon State University's Marine Mammal Institute, flew UAVs to collect video and image data on the gray whale population that forages near the PacWave test facility. We will use her dataset to train a machine learning program to analyze gray whale behavior and identify individuals that use the Oregon Coast to forage. With machine learning improvements, we will be able to increase aerial-based imagery data-processing capabilities and analysis time.  

The benefits of this study will include learning more about wildlife interactions with marine energy systems and filling knowledge gaps about displacement. This project is particularly compelling because we can integrate commercial off-the-shelf technologies (aerial technology, optical and infrared sensors, and machine learning software) to improve data collection methods and aerial technologies to answer important questions about animal displacement that are necessary to remove barriers to marine energy testing and implementation.  

Alicia Amerson and Joe Haxel

Anthropogenic Light Project  

Alicia Amerson and Joe Haxel here! We're thrilled to tell you about an exciting new RSRI topic we will be exploring in Triton 3.0.  

Human-introduced light at night is an essential aspect of the engineered marine environment, providing navigational aids for transitory routes near artificial structures and other natural hazards, such as large reefs or rocks. However, anthropogenic light at night can disrupt the physiology and behaviors of wildlife in marine and coastal environments. Lights may attract marine wildlife such as zooplankton, fish, birds, turtles, crustaceans, and marine mammals to a project area, leading to various potentially negative impacts. With limited marine energy devices being tested or deployed in U.S. waters, there is minimal research on how light may affect the marine wildlife that cohabitates with these devices.  

The project will assess relevant literature on the wildlife impacts from anthropogenic light, particularly related to species and ecology in the marine environment, by reviewing other maritime industry impacts such as lighting on oil and gas platforms. We will focus on investigating lighting impacts on sensitive and indicator species, look at relevant standards and requirements for marine lighting aids for navigation and safety, and categorize the intended function of types of marine lighting. Our partner in this research is Dr. Morgan Pattinson, PhD, the chief executive officer of Solid State Lighting Services, Inc., who works closely with terrestrial wildlife impacts associated with light at national parks. Through this partnership, we will review lighting requirements and consider wildlife impacts for developing and evaluating technical strategies for impact mitigation in the context of marine energy systems. This research will include a review of new lighting technology applications in terms of spectral power distribution (color), optical distribution, and intensity control to reduce impacts on local wildlife while also achieving necessary safety and navigation requirements. This work will identify gaps in understanding and shortcomings found in existing literature to determine possible field research efforts to address those needs.  

Because little is known about this potential stressor to marine wildlife as it relates to marine energy, we have an opportunity to inform recommendations to the industry that may lessen the stress or impact of light at night on marine wildlife as more devices are permitted and deployed. We can't wait to dive in!  

Noelani Boise profile photo

Triton Webinar Series 

My name is Noelani Boise, and I am an environmental scientist supporting Triton in its quest to communicate and disseminate the project's environmental monitoring technology development and research.  

Amid a global crisis, effective virtual communication is critical for bridging the gap between technical researchers and developers, sponsors, and the general public to move the needle for the marine energy industry. Over the past several years, the Triton team has researched the Triton Field Trials (TFiT). TFiT is a campaign that explores cost-effective methods and technologies to monitor potential environmental stressors associated with marine energy systems and performs field tests on those various instruments at diverse field sites. The outcomes of this project are collated in a set of recommendations for the use of environmental monitoring technology and methods to study and understand collision riskchanges in habitatEMF, and underwater noise. The team will publish these results and recommendations in a special issue in the Journal of Marine Science and Engineering titled "Technology and Methods for Environmental Monitoring of Marine Renewable Energy."  

In collaboration with Cailene Gunn, Triton will launch a monthly webinar series coinciding with the publication of this special issue. The series will dive into the TFiT results and recommendations and highlight Triton's RSRI research throughout the year. These webinars will enable marine energy stakeholders, research partners, and interested laypeople to learn about Triton's environmental monitoring research regularly and contribute to virtual discussions about research on the ecological effects of marine energy.  

We look forward to the opportunity to engage with all types of audiences and share the meaningful work Triton is doing to help advance the marine energy industry in an environmentally responsible manner. With this webinar series, Triton hopes to create a resource for broad audiences to learn about Triton's various projects and feel empowered to ask questions and offer feedback on Triton's research. Increased access to results and awareness of the science conducted to advance marine energy safely and sustainably helps inform permitting of marine energy device testing to move the industry closer to a cleaner energy portfolio in the United States. Stay tuned for more information on the webinar series, launching early in 2022!  

Triton 3.0 is made possible by funding from the Department of Energy Water Power Technologies Office. This new suite of projects all help propel the project's mission and expand the types of environmental monitoring data and instruments available to build confidence in the safety of marine energy technologies.  

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