Presentations and Papers

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https://hdl.handle.net/1912/12

This collection represents presentations made by members of the staff of the MBLWHOI Library or at the behest of the Library, and articles authored by members of the Library staff.

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Browsing Presentations and Papers by Subject "Acoustics"
  • Article
    Diel vertical migrators respond to short-term upwelling events
    (American Geophysical Union, 2024-01-18) Sato, Mei ; Benoit-Bird, Kelly J.
    Pelagic organisms inhabiting coastal upwelling regions face a high risk of advection away from the nearshore productive habitat, potentially leading to mortality. We explored how animals remain in a productive yet highly advective environment in the Northern California Current System using the cabled observatory system located off the Oregon coast. Acoustic scatterers consistent with swimbladder-bearing fish were only present during the downwelling season as these animals avoided the cold waters associated with strong upwelling conditions in summer and fall. Fish responded to short-term upwelling events by increasing the frequency of diel vertical migration. Throughout the study, their vertical positions corresponded to the depth of minimum cross-shelf transport, providing a mechanism for retention. The observed behavioral response highlights the importance of studying ecological processes at short timescales and the abilities of pelagic organisms to control their horizontal distributions through fine-tuned diel vertical migration in response to upwelling.
  • Article
    Understanding the relationship between the Bering Sea Cold Pool and vocal presence of odontocetes in the context of climate changea)
    (Acoustical Society of America, 2024-04-03) Miksis-Olds, Jennifer L. ; Seger, Kerri D. ; Johnson, Jennifer J.
    The Cold Pool is a subsurface layer with water temperatures below 2 °C that is formed in the eastern Bering Sea. This oceanographic feature of relatively cooler bottom temperature impacts zooplankton and forage fish dynamics, driving different energetic pathways dependent upon Bering Sea climatic regime. Odontocetes echolocate to find prey, so tracking foraging vocalizations acoustically provides information to understand the implications of climate change on Cold Pool variability influencing regional food web processes. Vocal foraging dynamics of ice-associated and seasonally migrant marine mammal species suggest that sperm whales spend more time searching for prey in warm years when the Cold Pool is reduced but are more successful at capturing prey during cold years when the Cold Pool is stronger. Beluga whale foraging vocal activity was relatively consistent across climate regimes but peaked during the warm regime. Killer whale foraging vocal activity peaked in both warm and cold regimes with indicators of different ecotypes exploiting changing prey conditions across climate regimes. Foraging activity of odontocete apex predators may serve as a sentinel indicator of future ecosystem change related to prey availability that is linked to a diminishing Cold Pool as water temperatures rise and seasonal sea ice decreases due to climate change.