A5056604154- Marine and fisheries research
- Underwater Acoustics Research
- Marine animal studies overview
- Fish Ecology and Management Studies
- Marine Bivalve and Aquaculture Studies
- Astrophysics and Star Formation Studies
- Adaptive optics and wavefront sensing
- Rabies epidemiology and control
- Venomous Animal Envenomation and Studies
- Myxozoan Parasites in Aquatic Species
- Aquatic Invertebrate Ecology and Behavior
- Stellar, planetary, and galactic studies
- Arctic and Antarctic ice dynamics
- Vibration and Dynamic Analysis
- Fish Biology and Ecology Studies
- Ichthyology and Marine Biology
- Ultrasonics and Acoustic Wave Propagation
- Underwater Vehicles and Communication Systems
Norwegian Institute of Marine Research
2008-2022
Acoustics (Norway)
2020-2022
Abstract High abundance of Northeast Atlantic mackerel (Scomber scombrus L.), combined with limited food resources, may now force to enter new and productive regions in the northern Norwegian Sea. However, it is not known how exploit spatially varying feeding their vertical distribution swimming behaviour are also largely unknown. During an ecosystem survey Sea during summer season, direction, speed schools were recorded high-frequency omnidirectional sonar four different relative currents,...
Abstract Peña, H., Handegard, N. O. and Ona, E. 2013. Feeding herring schools do not react to seismic air gun surveys. – ICES Journal of Marine Science, 70: 1174–1180. The real-time behaviour exposed a full-scale 3D survey off Vesterålen, northern Norway, was observed using an omnidirectional fisheries sonar. Throughout the study period, swam slowly against predominant northeast current, with net displacement along current. mean swimming speed after subtracting drift velocities 0.35 m s−1,...
Abstract Weber, T. C., Peña, H., and Jech, J. M. 2009. Consecutive acoustic observations of an Atlantic herring school in the Northwest Atlantic. – ICES Journal Marine Science, 66: 1270–1277. Several successive images same (Clupea harengus) were collected over course ∼1 h just north Georges Bank Although fish may not have been their natural, undisturbed state, we observed what appeared to be fragmenting dispersing, using a split-beam multibeam echosounder. Calibrated, 38 kHz, echosounder...
Abstract Peña, H., and Foote, K. G. 2008. Modelling the target strength of Trachurus symmetricus murphyi based on high-resolution swimbladder morphometry using an MRI scanner. – ICES Journal Marine Science, 65: 1751–1761. The acoustic (TS) Chilean jack mackerel (Trachurus murphyi) was computed from three-dimensional reconstructions form. primary morphometric data were derived images made with a clinical whole-body 3-tesla magnetic resonance imaging (MRI) fish obtained commercial purse-seiner...
The acoustic backscatter from pressure release prolate spheroids and a three-dimensional representation of fish swimbladder (Chilean jack mackerel, Trachurus symmetricus murphyi) was calculated using four target strength models (Kirchhoff-approximation, Kirchhoff-ray-mode, finite element solution the Helmholtz equation, prolate-spheroid-modal-series). Smoothly varying errors were found in Kirchhoff-approximation Kirchhoff-ray-mode model results when compared to other models, provide...
To ensure efficient and sustainable purse-seine fisheries, the catch process must be monitored to better understand reactions of fish gear. In this study, we behaviours herring (Clupea harengus) mackerel (Scomber scombrus) schools during capture using a multibeam imaging sonar (Simrad MS70, 75–112 kHz) mounted on research vessel. The differed between species sets. For both species, acoustic volume backscattering coefficient increased as 0–80% seine was hauled aboard, indicating corresponding...
Abstract Peña, H. 2008. In situ target-strength measurements of Chilean jack mackerel (Trachurus symmetricus murphyi) collected with a scientific echosounder installed on fishing vessel. – ICES Journal Marine Science 65: 594–604. The use commercial vessels for purposes has increased worldwide in the past 10 years. Many such studies have involved collection acoustic data from both uncalibrated and calibrated echosounders. However, few investigations target strength (TS). During...
Multi-beam sonar is commonly used in purse seine fishing to visually evaluate school size and biomass. However, quantitative analyses of the across-beam dimensions may provide more accurate estimates volumes. These help fishers improve their fish biomass prior setting a set; assist scientists accurately assess distributions abundances pelagic schooling fishes. Fish-school volumes are evaluated using data from simulated Simrad SX90 sonar. The accuracy dependent on number ensonifying beams,...
Abstract Pelagic fishes are a major source of protein and unsaturated fatty acids, robust management is critical to avoid overfishing. Fisheries often supported by indices from scientific acoustic-trawl surveys, where vertically aligned echo sounders trawl samples used provide an estimate abundance. Survey biases may be introduced when fish located near the sea surface or if they survey vessel. Horizontally scanning acoustic equipment, such as fish-detection sonars, have been proposed method...
Abstract Economic profitability and responsible fisheries are objectives of fishermen managers. In purse seine fisheries, an accurate biomass estimate the targeted school is crucial to accomplish this. For this study, omnidirectional sonar was used individual Norwegian spring spawning herring (Clupea harengus) Atlantic mackerel (Scomber scombrus). A sampling design based on professional skipper’s experience provided detailed information dimensions acoustic backscattering. Using calibrated...
Abstract We present the James Clerk Maxwell Telescope (JCMT) 850 μ m Legacy Release, containing uniformly reduced, coadded tiles, and catalogs of detected emission, for data from all Submillimetre Common User Bolometer Array 2 (SCUBA-2) observations taken between 2011 February 2020 August 1. This release provides fastest easiest way to identify determined detections calibrated fluxes any position observed by JCMT. The include 11,722 hr observing time cover 1516 square degrees sky, with...
Abstract A method is proposed to estimate and correct athwart-beam distortion of multibeam sonars advance sonar-based abundance estimation. We illustrate its application using data from a Simrad SN90 sonar aboard tropical tuna purse-seiner, targeting mixed fish aggregations around drifting Fish Aggregating Devices (dFADs) in the Atlantic Ocean. To calculate horizontal swath, measurements were compared with more accurate simultaneous along-beam measurements. For vertical swath correction, we...
In September 2006, several schools of Atlantic herring were simultaneously imaged with a Reson 7125 SeaBat multibeam sonar (400 kHz) and Simrad EK60 Scientific echo sounder (38 kHz, 120 200 on Georges Bank in the Gulf Maine. One school was five separate times over span one hour. These two systems, along pelagic trawl catch data collected ship, provided synoptic view fish as it changed depth size, fragmented, eventually dispersed. Of particular interest is combination from sonars. The...
Fish target strength is primarily dependent on the physical dimensions of fish, acoustic frequency, and orientation fish. In traditional vertically observing echosounder surveys, fish are insonified in dorsal aspect with fairly limited tilt angle variation. oblique-angled sonar however, may be at other aspects. For herring, also depth as they cannot refill swimbladder depth. Understanding from several insonification angles thus required for quantitative measurements sonar. The dataset used...
Improved knowledge about target tilt can be used to improve acoustic estimates of abundance and gain insights into the behavioural patterns exploited marine species. This is because angle strongly affects backscatter, especially at high frequencies. In order estimate tilt, a dual-transducer system for synchronous observation organisms two angles (0o 9o) 38 kHz was tested. Data characterized via "angle response"; area backscatter from one transducer divided by sum both. metric computed layers...
An ocean acoustics waveguide remote sensing (OAWRS) system was deployed in the Gulf of Maine, near Georges Bank to image Atlantic herring and other fish populations from Sep-Oct 2006. OAWRS provides spatially unaliased imaging over wide areas, spannning 100 km diameter. Migration spawning behaviour observed using several diurnal periods, including massive movements on off bank spawn. Measurements made simultaneously with a conventional fish-finding echosounder (CFFS) multibeam sonar provide...