Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids
Acoustic assessment of Bering Sea euphausiids and their predators can provide useful data for ecosystem studies if the acoustic scattering characteristics of these animals are known. The amount of acoustic energy that is scattered by different marine zooplankton taxa is strongly affected by the cont...
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ftstateuny:oai:dspace.sunyconnect.suny.edu:1951/55627 2023-05-15T15:43:11+02:00 Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids Smith, Joy Nicole Warren, Joseph D. Department of Marine and Atmospheric Science 1-Aug-10 Electronic Resource application/pdf http://hdl.handle.net/1951/55627 en_US eng The Graduate School, Stony Brook University: Stony Brook, NY. Smith_grad.sunysb_0771M_10249.pdf http://hdl.handle.net/1951/55627 Biology Oceanography -- Applied Mathematics acoustics Bering Sea modeling target strength zooplankton Thesis ftstateuny 2021-03-08T12:02:58Z Acoustic assessment of Bering Sea euphausiids and their predators can provide useful data for ecosystem studies if the acoustic scattering characteristics of these animals are known. The amount of acoustic energy that is scattered by different marine zooplankton taxa is strongly affected by the contrast of the animal's density (g) and sound speed (h) with the surrounding seawater. Density and sound speed contrast were measured in the Bering Sea during the summer of 2008 for several different zooplankton and nekton taxa including: euphausiids (Thysanoessa inermis, Thysanoessa raschii, and Thysanoessa spinifera), copepods, amphipods, chaetognaths, gastropods, fish larvae, jellyfish, and squid. Density contrast values varied between different taxa as well as between individual animals within the same species. Sound speed contrast was measured for monospecific groups of animals and differences were found among taxa. The range, mean, and standard deviation of g and h for all euphausiid species were: g = 1.001-1.041; 1.018 ñ 0.009 and h = 0.990-1.017; 1.006 ñ 0.008. Changes in the relationship between euphausiid material properties and animal length, seawater temperature, seawater density, and geographic location were also evaluated. Results suggest that environmental conditions at different sample locations led to significant differences in animal density and material properties.Acoustic surveys monitor euphausiid populations in the Bering Sea because of their importance as prey walleye pollock. Various scattering models exist to convert acoustic survey data to numerical density estimates of euphausiids, but a target strength (TS) model specific to Bering Sea euphausiids did not exist. This study parameterized a distorted wave Borne approximation model using measured lengths and material properties (density contrast, g, and sound speed contrast, h) from live euphausiids. All model parameters (length, g, h, shape, orientation) were evaluated for their effect on TS estimates. Stony Brook University Libraries. SBU Graduate School in Department of Marine and Atmospheric Science. Lawrence Martin (Dean of Graduate School). Advisor(s): Joseph D -- Warren. Committee Member(s): Patrick H. Ressler; Stephan B -- Munch. Thesis Bering Sea Thysanoessa raschii Copepods Thysanoessa inermis The State University of New York: SUNY Digital Repository Bering Sea |
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Open Polar |
collection |
The State University of New York: SUNY Digital Repository |
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ftstateuny |
language |
English |
topic |
Biology Oceanography -- Applied Mathematics acoustics Bering Sea modeling target strength zooplankton |
spellingShingle |
Biology Oceanography -- Applied Mathematics acoustics Bering Sea modeling target strength zooplankton Smith, Joy Nicole Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
topic_facet |
Biology Oceanography -- Applied Mathematics acoustics Bering Sea modeling target strength zooplankton |
description |
Acoustic assessment of Bering Sea euphausiids and their predators can provide useful data for ecosystem studies if the acoustic scattering characteristics of these animals are known. The amount of acoustic energy that is scattered by different marine zooplankton taxa is strongly affected by the contrast of the animal's density (g) and sound speed (h) with the surrounding seawater. Density and sound speed contrast were measured in the Bering Sea during the summer of 2008 for several different zooplankton and nekton taxa including: euphausiids (Thysanoessa inermis, Thysanoessa raschii, and Thysanoessa spinifera), copepods, amphipods, chaetognaths, gastropods, fish larvae, jellyfish, and squid. Density contrast values varied between different taxa as well as between individual animals within the same species. Sound speed contrast was measured for monospecific groups of animals and differences were found among taxa. The range, mean, and standard deviation of g and h for all euphausiid species were: g = 1.001-1.041; 1.018 ñ 0.009 and h = 0.990-1.017; 1.006 ñ 0.008. Changes in the relationship between euphausiid material properties and animal length, seawater temperature, seawater density, and geographic location were also evaluated. Results suggest that environmental conditions at different sample locations led to significant differences in animal density and material properties.Acoustic surveys monitor euphausiid populations in the Bering Sea because of their importance as prey walleye pollock. Various scattering models exist to convert acoustic survey data to numerical density estimates of euphausiids, but a target strength (TS) model specific to Bering Sea euphausiids did not exist. This study parameterized a distorted wave Borne approximation model using measured lengths and material properties (density contrast, g, and sound speed contrast, h) from live euphausiids. All model parameters (length, g, h, shape, orientation) were evaluated for their effect on TS estimates. Stony Brook University Libraries. SBU Graduate School in Department of Marine and Atmospheric Science. Lawrence Martin (Dean of Graduate School). Advisor(s): Joseph D -- Warren. Committee Member(s): Patrick H. Ressler; Stephan B -- Munch. |
author2 |
Warren, Joseph D. Department of Marine and Atmospheric Science |
format |
Thesis |
author |
Smith, Joy Nicole |
author_facet |
Smith, Joy Nicole |
author_sort |
Smith, Joy Nicole |
title |
Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
title_short |
Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
title_full |
Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
title_fullStr |
Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
title_full_unstemmed |
Physical Characteristics of Bering Sea Zooplankton and Their Use to Parameterize an Acoustic Scattering Model for Euphausiids |
title_sort |
physical characteristics of bering sea zooplankton and their use to parameterize an acoustic scattering model for euphausiids |
publisher |
The Graduate School, Stony Brook University: Stony Brook, NY. |
publishDate |
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url |
http://hdl.handle.net/1951/55627 |
geographic |
Bering Sea |
geographic_facet |
Bering Sea |
genre |
Bering Sea Thysanoessa raschii Copepods Thysanoessa inermis |
genre_facet |
Bering Sea Thysanoessa raschii Copepods Thysanoessa inermis |
op_relation |
Smith_grad.sunysb_0771M_10249.pdf http://hdl.handle.net/1951/55627 |
_version_ |
1766377233188913152 |