Inicio Inicio

CCAMLR

Comisión para la Conservación de los Recursos Vivos Marinos Antárticos

  • Inicio
  • Contenido
  • Inicio de sesión

Formulario de búsqueda

  • Acerca de la CCRVMA
  • Medidas de conservación
  • Ciencia
  • Pesquerías
  • Ejecución
  • Datos
  • Reuniones
  • Publicaciones
  • English
  • Français
  • Русский
  • Español
  • Inicio
  • Reuniones
  • WG-EMM-99/42
Print this page
Increase font size
Decrease font size

Effects of orientation on acoustic scattering from Antarctic krill at 120 kHz

Doc Number: WG-EMM-99/42
Autor(es): D.E. McGehee (USA), R.L. O’Driscoll (New Zealand) and L.V. Martin Traykovski (USA)
Submitted By: ()

Please complete a document request form to access this document

Inicio de sesión

  • Solicitar una nueva contraseña
Abstract: 

Backscattering measurements of 14 live individual Antarctic krill (Euphausia superb a) were made at a frequency of 120 kHz in a chilled insulated tank at the Long Marine Laboratory in Santa Cruz, CA. Individual animals were suspended in front of the transducers, were only loosely constrained, had substantial freedom to move, and showed more or less random orientation. One thousand echoes were collected per animal. Orientation data were recorded on video. The acoustic data were analyzed and target strengths determined from each echo. A method was developed for estimating the three-dimensional orientation of the krill based on the video images and was applied to five of them, giving their target strengths as functions of orientation. Scattering models based on a simplified distorted-wave Born approximation (DWBA) method were developed for five animals and compared with the measurements.
Both measured and modeled scattering patterns showed that 120 kHz acoustic scattering levels are highly dependent on animal orientation. Use of these scattering patterns with orientation data from shipboard studies of E. superba gave mean scattering levels approximately 12 dB lower than peak levels. These results underscore the need for better in situ behavioral data to properly interpret acoustic survey results. A generic E. superb a DWBA scattering model is proposed that is scalable by animal length. With good orientation information, this model could significantly improve the precision and accuracy of krill acoustic surveys.

This page was last modified on 30 Sep 2011

Datos de contacto

Correo electrónico: ccamlr [at] ccamlr [dot] org
Teléfono: +61 3 6210 1111
Facsímil: +61 3 6224 8744
Dirección: 181 Macquarie Street, Hobart, 7000, Tasmania, Australia
Dirección postal: PO Box 213, North Hobart 7002, Tasmania, Australia

 

Enlaces destacados

  • Ofertas de empleo
  • Lista de las medidas de conservación vigentes en la temporada 2019/20
  • Asistencia
  • Boletín Estadístico

Reuniones recientes y próximas

  • WG-ASAM-2020 - De 01 jun 2020 hasta 05 jun 2020
  • WG-SAM-2020 - De 29 jun 2020 hasta 03 jul 2020
  • WG-EMM-2020 - De 06 jul 2020 hasta 17 jul 2020
  • WG-FSA-2020 - De 12 oct 2020 hasta 23 oct 2020
  • SC-CAMLR-39 - De 26 oct 2020 hasta 30 oct 2020

Footer Links Spanish

  • Inicio de sesión
  • Correo electrónico
  • Grupos-e de la CCRVMA
  • Asistencia técnica
  • Derechos de autor
  • Descargo de responsabilidad y política de confidencialidad
  • Mapa del sitio
© Copyright - the Commission for the Conservation of Antarctic Marine Living Resources 2019, Todos los derechos están reservado..  |  Volver arriba  |  Sitio creado por Eighty Options