Z. Daniel Deng

The Juvenile Salmon Acoustic Telemetry System: A New Tool

Abstract Limitations of biotelemetry technology available in 2001 prompted the U.S. Army Corps of Engineers Portland District to develop a new acoustic telemetry system to monitor survival of juvenile salmonids through the Columbia River to the Pacific Ocean. Eight years later, the Juvenile Salmon Acoustic Telemetry System (JSATS) consists of microacoustic transmitters (12 mm long, 0.43 g weight in air), autonomous and cabled receiving systems, and data management and processing applications. Transmitter pulse rate can be user-defined and as configured for this case study was set at 5 seconds, with an estimated tag life of 30 days and detection range of 300 m. Before JSATS development, no technology existed to study movement and survival of fish smaller than 10 g migrating long distances from freshwater and into saltwater. In a 2008 study comparing detection probabilities, travel times, and survival of 4,140 JSATS-tagged and 48,433 passive integrated transponder (PIT)-tagged yearling Chinook salmon (Oncor...

Understanding Barotrauma in Fish Passing Hydro Structures: A Global Strategy for Sustainable Development of Water Resources

ABSTRACTFreshwater fishes are one of the most imperiled groups of vertebrates, and population declines are alarming in terms of biodiversity and to communities that rely on fisheries for their livelihood and nutrition. One activity associated with declines in freshwater fish populations is water resource development, including dams, weirs, and hydropower facilities. Fish passing through irrigation and hydro infrastructures during downstream migration experience a rapid decrease in pressure, which can lead to injuries (barotrauma) that contribute to mortality. There is renewed initiative to expand hydropower and irrigation infrastructure to improve water security and increase low-carbon energy generation. The impact of barotrauma on fish must be understood and mitigated to ensure that development is sustainable for fisheries. This will involve taking steps to expand the knowledge of barotrauma-related injury from its current focus, mainly on seaward-migrating juvenile salmonids of the Pacific Northwest, to...

Tunable electrochemical properties of fluorinated graphene

The structural and electrochemical properties of fluorinated graphene have been investigated by using a series of graphene fluorides (CFx, x = 0.47, 0.66, 0.89). Fluorinated graphene exhibited high capacity retentions of 75–81% of theoretical capacity at moderate rates as cathode materials for primary lithium batteries. Specifically, CF0.47 maintained a capacity of 356 mA h g−1 at a 5 C rate, superior to that of traditional fluorinated graphite. The discharged graphene fluorides also provide an electrochemical tool to probe the chemical bonding on the parent graphene substrate.

The Effects of Neutrally Buoyant, Externally Attached Transmitters on Swimming Performance and Predator Avoidance of Juvenile Chinook Salmon

Abstract Migrating juvenile salmonids experience rapid decompression that could result in injury or mortality due to barotrauma as they pass turbines at hydropower facilities. Recent research indicates that the risk of injury or mortality due to barotrauma is higher in fish bearing surgically implanted transmitters. Since tagged fish are used to represent the entire population, this tag effect potentially leads to inaccuracies in survival estimates for fish passing turbines. This problem led to development of a novel transmitter, the use of which may eliminate bias associated with the passage of transmitter-bearing fish through turbines. Juvenile Chinook salmon Oncorhynchus tshawytscha were tagged with two different neutrally buoyant, externally attached transmitters (types A and B). The effects of transmitter presence on swimming performance were examined by comparing critical swimming speeds (Ucrit ; an index of prolonged swimming performance) of externally tagged fish, untagged individuals, and fish th...

Design and Implementation of an Underwater Sound Recording Device

To monitor the underwater sound and pressure waves generated by anthropogenic activities such as underwater blasting and pile driving, an autonomous system was designed to record underwater acoustic signals. The underwater sound recording device (USR) allows for connections of two hydrophones or other dynamic pressure sensors, filters high frequency noise out of the collected signals, has a gain that can be independently set for each sensor, and allows for 2 h of data collection. Two versions of the USR were created: a submersible model deployable to a maximum depth of 300 m, and a watertight but not fully submersible model. Tests were performed on the USR in the laboratory using a data acquisition system to send single-frequency sinusoidal voltages directly to each component. These tests verified that the device operates as designed and performs as well as larger commercially available data acquisition systems, which are not suited for field use. On average, the designed gain values differed from the actual measured gain values by about 0.35 dB. A prototype of the device was used in a case study to measure blast pressures while investigating the effect of underwater rock blasting on juvenile Chinook salmon and rainbow trout. In the case study, maximum positive pressure from the blast was found to be significantly correlated with frequency of injury for individual fish. The case study also demonstrated that the device withstood operation in harsh environments, making it a valuable tool for collecting field measurements.

A 3D approximate maximum likelihood solver for localization of fish implanted with acoustic transmitters

Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developed using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.

The effect of an externally attached neutrally buoyant transmitter on mortal injury during simulated hydroturbine passage

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing through hydroturbines experience a rapid decrease in pressure as they pass by the turbine blade. The severity of this decompression can be highly variable but can result in injuries such as swim bladder rupture, exophthalmia, and emboli and hemorrhaging in the fins and tissues. Recent research indicates that the presence of a telemetry tag (acoustic, radio, inductive) implanted inside the coelom of a juvenile salmon increases the likelihood that the fish will be injured or die during turbine passage. Thus, previous turbine passage survival research conducted using telemetry tags implanted into the coelom of fish may have been inaccurate. Therefore, a new technique is needed to provide unbiased estimates of survival through turbines. This study evaluated the effectiveness of a neutrally buoyant externally attached acoustic transmitter on decompression-stressed juvenile Chinook salmon. Both nontagged fish and fish ...

A Field Evaluation of an External and Neutrally Buoyant Acoustic Transmitter for Juvenile Salmon: Implications for Estimating Hydroturbine Passage Survival

Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System) used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT) tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm) downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss) to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days) single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to confirm this.

Perspective: Towards environmentally acceptable criteria for downstream fish passage through mini hydro and irrigation infrastructure in the Lower Mekong River Basin

Tropical rivers have high annual discharges optimal for hydropower and irrigation development. The Mekong River is one of the largest tropical river systems, supporting a unique mega-diverse fish community. Fish are an important commodity in the Mekong, contributing a large proportion of calcium, protein, and essential nutrients to the diet of the local people and providing a critical source of income for rural households. Many of these fish migrate not only upstream and downstream within main-channel habitats but also laterally into highly productive floodplain habitat to both feed and spawn. Most work to date has focused on providing for upstream fish passage, but downstream movement is an equally important process to protect. Expansion of hydropower and irrigation weirs can disrupt downstream migrations and it is important to ensure that passage through regulators or mini hydro systems is not harmful or fatal. Many new infrastructure projects (<6 m head) are proposed for the thousands of tributary stre...

Broadband Acoustic Environment at a Tidal Energy Site in Puget Sound

Located near shipping lanes, as a possibly highly variable acoustic environment that is frequented by the endangered Southern Resident killer whale (SRKW), Admiralty Inlet, Puget Sound, Washington, has been selected as a potential tidal energy site. The first step to receiving approval to deploy tidal turbines is resolving environmental impacts. In order to determine the presence of SRKW near the turbines, several monitoring technologies are being considered. Broadband noise level measurements are critical for determining design and operational specifications of these technologies. Using a cabled vertical line array from two cruises during flood and ebb tidal periods in May and June 2011,acoustic environment data at the proposed site were acquired at different depths. The ambient noise level decreases approximately 5 dB re 1 μPa per octave for frequency ranges of 1-70 kHz and increases approximately 5 dB re 1 μPa per octave for the frequency from 70 to 100 kHz. The difference between noise pressure levels in different months varies from 10 to 30 dB re 1 μPa for the frequency range below 70 kHz. The most significant contributors to sound pressure levels for the frequency range of 1-50 kHz were found to be commercial shipping and ferry vessel traffic, and the variation could be as high as 30 dB re 1 μPa. The basic information for designing and evaluating both active and passive monitoring systems proposed for deployment and operation of a tidal power generation alert system are provided by these noise level measurements.