Juvenile Chinook salmon (age 0 and age 1), steelhead, and sockeye salmon were acoustic tagged and released at sites along the Yakima River in and below Yakima, WA 2018-2024. Detection sites varied across years but included arrays placed at diversion dams, canals, hydropower facilities, and other locations throughout the Yakima and Columbia rivers. Study design included paired fish releases above and below irrigation diversions to evaluate effects on fish movement and survival. Overall, the purpose of this study was to evaluate the effects of barriers and other structures on juvenile Chinook salmon and steelhead behavior and survival across variable hydrological conditions.

During the period of 1987 to 1994, Robin J. LeBrasseur and N. Brent Hargreaves lead a juvenile salmon predation research project in Alberni Inlet and Barkley Sound BC. This dataset contains the research survey catch data and individual fish examinations data.

Federally-threatened ago-0 spring Chinook salmon (Oncorhynchus tshawytscha) were acoustic tagged and released near Lookout Point Reservoir to estimate passage and survival during an experimental reservoir drawdown operation that was designed to facilitate downstream passage through two reservoirs and dams. The experimental operation consisted of lowering the water surface elevation of Lookout Point Reservoir on the Middle Fork Willamette River from 823 ft in late August 2023 to 750 ft by early November 2023 and passing water through regulating outlets at Lookout Point Dam. This operation was intended to improve fish passage for juvenile Chinook salmon through Lookout Point Dam. During our study, acoustic-tagged juvenile Chinook salmon produced by Oregon State University's Wild Fish Surrogate Program were released weekly during late August to late October to determine how fish responded to the drawdown. Detection sites were in Lookout Point Reservoir and Dexter Reservoir on the Middle Fork Willamette River; and near the city of Eugene, Oregon, and near Willamette Falls on the Willamette River. Estimates of fish survival through the study area were calculated from the release and detection records and combined with time-varying covariates of Lookout Dam operations and water temperature in Lookout Point Reservoir and the Middle Fork Willamette River.

Sound recordings were made in Tuxedni Bay and Chinitna Bays, Cook Inlet, Alaska. These recordings (files.wav) were made from ST-600HF sound recorders (Ocean Instruments NZ) programmed to sample on a duty cycle of 5 minutes on and 10 minutes off with a sampling rate of 48 kHz. Echolocation logs (files.FP1) from F-POD echolocation loggers (Chelonia Ltd.) sampled the frequency range of 40 to 160 kHz on a continuous basis from May to September and on a duty cycle of 1 minute every 2 minutes from October to April. Species recorded include harbor porpoise, beluga whales, killer whales, and humpback whales.

Drs. Marla Holt, Brad Hanson, and Candice Emmons of the NWFSC, along with efforts from the NWFSC dive team (coordinated by Nick Tolimieri), are currently conducting passive acoustic monitoring of harbor porpoises in Puget Sound. The occurrence of harbor porpoises are being acoustically documented using porpoise detectors (CPODs, made by Chelonia, Ltd), which detect and log harbor porpoise echolocation clicks and store the data on flash memory cards. CPODs are deployed on the sea floor by scientific divers, and must be recovered every three months to replace batteries and memory cards. The project is ongoing, and will document occurrence and habitat use of this protected marine species. The project is a well-defined component of a larger study that addresses harbor porpoise occurrence and habitat use in the Salish Sea. Passive acoustic monitoring.

This dataset consists of a complete set of audio recordings collected near a large walrus haulout at Point Lay, Alaska, during September of 2024. The recordings were collected using the Song Meter Mini 2 (Wildlife Acoustics, Inc., Maynard, MA) at two sites, one within 150 m of a large walrus herd resting on shore and one placed more than 4 km to the south of the herd directly under the approach path of aircraft servicing the Point Lay runway from and to the west. Audio recording were analyzed for the presence of walrus and a summary table of events is available with this data release. During the course of recording the walrus herd shifted south to within 40 m of the herd recorder. Specific herd locations interpreted from drone survey imagery, herd outlines, and satellite imagery are available to view in USGS data releases: Fischbach et al. 2025, https://doi.org/10.5066/P1CNBKN8,; Fischbach 2025, https://doi.org/10.5066/P1BFYBHG; and Fischbach and Douglas 2022, https://doi.org/10.5066/P9CSM0KN, respectively. Specific approach paths for aircraft arriving to and departing from Point Lay are published by the FAA. Three approach procedure charts for the Point Lay runways are available in FAA 2024.

Scientists from the Midwater Assessment and Conservation Engineering (MACE) Program of the Alaska Fisheries Science Center's (AFSC) Resource Assessment and Conservation Engineering (RACE) Division conducted an acoustic-trawl (AT) stock assessment survey of the western Gulf of Alaska (GOA) shelf to estimate the distribution and abundance of walleye pollock (Gadus chalcogrammus) in summer 2015. Previous surveys of the GOA were also conducted during the summers of 2003, 2005, 2011, and 2013 by MACE. The 2015 survey covered the shelf from the Islands of Four Mountains to Yakutat Trough including many associated bays and troughs. The biomass estimate for the entire survey area was 1,482,668 t. The majority of the pollock observed were located on the continental shelf (64%), Shelikof Strait (19%), east of Kodiak Island in Chiniak (2%) and Barnabas Troughs (6%), and in Marmot Bay (3%). The vast majority (91%) of the biomass for the entire survey was from fish 30-50 cm in length (likely mostly age-3 fish), Fish weight at length was slightly lower in fish greater than 40 cm FL compared to surveys conducted in the summer GOA in previous years. Backscatter was attributed to other species where possible. A biomass estimate was also calculated for Pacific ocean perch (Sebastes alutus, 407,988 t) and the relative abundance and distribution for euphausiids (primarily consisting of Thysanoessa inermis, but also including T. spinifera, T. raschii, and Euphausia pacifica) was estimated.

This data release includes images and field measurements used to map salmon spawning locations along the American River near Sacramento, California, via remote sensing; the data were collected November 5-7, 2018. The purpose of this study was to develop and test a spectrally based technique for identifying salmon spawning locations, known as redds, from various types of remotely sensed data. Traditionally, redds have been mapped by eye while walking the bank or from a boat, or by an observer in an aircraft or an interpreter visually examining aerial images. The goal of this proof-of-concept investigation was to assess the potential for more efficient, objective, and automated redd mapping from conventional true color (RGB, or red/green/blue) and hyperspectral images. This child page provides redd locations mapped in the field, with their coordinates defined by surveying the redd centers with real-time kinematic (RTK) GPS receivers. The field-mapped redds were used to train and validate various image-based approaches to mapping salmon spawning locations.

Scientists from the Midwater Assessment and Conservation Engineering (MACE) Program of the Alaska Fisheries Science Center's (AFSC) Resource Assessment and Conservation Engineering (RACE) Division routinely conduct echo integration-trawl (EIT) stock assessment surveys in the Gulf of Alaska (GOA) during late winter and early spring to estimate the distribution and abundance of walleye pollock (Theragra chalcogramma). Surveys were conducted in the Shumagin Islands area in 1994-96, 2001-03, and 2005-07 and along the GOA continental shelf break east of Chirikof Island to Barnabas Trench in 2002-07. This report presents the distribution and abundance of walleye pollock for surveys conducted in the Shumagins during February and March 2009.

The acoustic trawl database for Lynn Canals echo-trawl survey was conducted from 2001 to 2004 throughout southern Lynn Canal in southeast Alaska. Acoustic surveys were conducted one day per month and trawl surveys were conducted every 3 months to verify acoustic signals and collect biological data. This study was conducted to study the relationship between Steller sea lions (Eumetopias jubatus) and their prey. Additional acoustic surveys were conducted throughout the winter of 2004 to 2005 on 6 consecutive days once a month in order to study forage fish hots spots. Acoustic equipment were calibrated before every trawl survey. Acoustic data were analyzed by the same qualified acoustician throughout the surveys duration with calibrations entered into the analytical software after each calibration. Trawls were used to identify the fish species associated with a specific acoustic signal and to get length weight data per species. Trawl data were also used to enumerate and identify all nekton found within the study area and to generate length frequencies, species composition and abundance by species and season. The acoustic data was use to generate biomass estimates for Pacific herring and walleye pollock. Longlines were deployed to better identify and enumerate the benthic species not usually caught in pelagic trawls.