Jellyfish and Juvenile Salmon Associations with Oceanographic Characteristics during Warm and Cool Years in the Eastern Bering Sea

• Main Authors: Kristin Cieciel, Edward V. Farley, Lisa B. Eisner
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: jellyfish; salmon; climate; eastern Bering Sea; Bering Sea; Keta
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.155.1548; http://www.npafc.org/new/publications/Bulletin/Bulletin%20No.%205/NPAFC_Bull_5_209-224(Cieciel).pdf

Abstract: We explored possible associations between jellyfish biomass (Aequorea spp., Aurelia labiata, Chrysaora melanaster, and Cyanea capillata), juvenile salmon (Oncorhynchus keta, O. nerka, O. gorbuscha, O. kisutch, and O. tshawytscha) abundance, and oceanographic characteristics (temperature, salinity, chlorophyll-a, and bottom depth) during two warm years (2004, 2005) and two cool years (2006, 2007) in the eastern Bering Sea from the annual Bering-Aleutian Salmon International Surveys (US BASIS). A significant difference was observed in the mean relative biomass of the four jellyfish species in response to the various conditions in warm versus cool years. Our results indicated that juvenile O. tshawytscha were significantly associated with cooler temperatures in only cool years and shallower bottom depths in all years. Juvenile O. kisutch were associated with shallower than average bottom depths for all years and juvenile O. keta had only cool-year associations with lower salinities and shallower bottom depths. Similar spatial distributions were seen between jellyfish and juvenile salmon, suggesting the possibility of competition. Immature O. keta were significantly associated with the same physical ocean factors as Aequorea spp. during fall warm years, indicating a potential for interaction.