Browsing Brage IMR by Author "Gibbons, Mark J."

Now showing items 1-3 of 3

    • Acoustic observations of jellyfish in the Namibian Benguela 

      Brierley, Andrew S.; Axelsen, Bjørn Erik; Buecher, Emmanuelle; Sparks, Conrad A. J.; Boyer, Helen; Gibbons, Mark J. (Journal article; Peer reviewed, 2001-01-26)
      Multi-frequency acoustic data (18, 38 and 120 kHz) were collected in conjunction with pelagic trawl sampling for gelatinous macrozooplankton during a cruise to the Namibian Benguela in September 1999. Sampling focused ...

    • Spatial dynamics of the bearded goby and its key fish predators off Namibia vary with climate and oxygen availability 

      Salvanes, Anne Gro V.; Bartholomae, Chris; Yemane, Dawit; Gibbons, Mark J.; Kainge, Paul; Krakstad, Jens-Otto; Rouault, Mathieu; Staby, Arved; Sundby, Svein (Journal article; Peer reviewed, 2015-02-06)
      Hypoxia [O2 < 2.0 mL L−1 (87 μmol kg−1)] and severely hypoxic water masses [O2 < 0.5 mL L−1 (21.8 μmol kg−1)] are increasing in coastal marine ecosystems due to eutrophication and warming. Here, we investigate the response ...

    • Towards the acoustic estimation of jellyfish abundance 

      Brierley, Andrew S.; Boyer, D.; Axelsen, Bjørn Erik; Lynam, Christopher P.; Sparks, Conrad A. J.; Boyer, Helen; Gibbons, Mark J. (Journal article; Peer reviewed, 2005-06-23)
      Acoustic target strengths (TSs) of the 2 most common large medusae, Chrysaora hysoscella and Aequorea aequorea, in the northern Benguela (off Namibia) have previously been estimated (at 18, 38 and 120 kHz) from acoustic ...