Factors Influencing the Acoustic Behavior and Nearshore Residence of the Gray Whale (Eschrichtius robustus) along their Migration Route

Abstract

Our long-term goal is to quantify the acoustic behavior of gray whales in the coastal waters of the Northeast Pacific Ocean and to characterize the link between coastal residency patterns of these migratory mammals and the distribution of hyperbenthic swarms of their primary prey (mysids). Several years of observations off the Oregon coast have revealed considerable interannual variability in the residence patterns of gray whales as well as in foraging behavior (Newell and Cowles 2006). For example, during the summer of 2005, the resident gray whale population had 50% fewer individuals than the previous three summers, and those 2005 residents displayed many fewer characteristic feeding behaviors than residents in other summers. This variability in residency and foraging was likely due to changes in the distribution and abundance of swarms of benthic mysids, the gray whale s preferred prey in this region. We have observed that the resident gray whales repeatedly forage on discrete hyperbenthic mysid swarms throughout the spring and summer months (late April late September).

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2011
Accession Number
ADA597899

Entities

People

  • David Mellinger
  • Kelly Benoit-Bird
  • Timothy J. Cowles

Organizations

  • Oregon State University

Tags

DTIC Thesaurus Topics

  • Abstracts
  • Acoustic Detectors
  • Acoustics
  • Detection
  • Detectors
  • Frequency
  • Frequency Response
  • Human Behavior
  • Mammals
  • Marine Mammals
  • Migration
  • Observation
  • Oceanography
  • Oceans
  • Odontocetes
  • Pacific Ocean
  • Universities

Fields of Study

  • Environmental science

Readers

  • Atmospheric Science/Meteorology
  • Marine Mammal Biology