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14.2: Definitions

  • Page ID
    10363
    • Contributed by Miracosta Oceanography 101
    • Sourced from Miracosta)

    Definitions

    • Planktonic: applies to organisms that float or drift with flowing currents (zooplankton are animals, phytoplankton are plants.)
    • Nektonic: applies to organism that actively move swim by their own means.
    • Pelagic: means relating to the open sea, chiefly shallow layers. Planktonic and nektonic organisms live in open water (more in chapter 16).
    • Benthic: means relating to, or occurring at the bottom of a body of water (oceans, lakes), relates to bottom-dwelling organism (more in chapter 15).
    The term benthic applies to:
    shoreline and nearshore environments (littoral and estuarine)
    littoral (pertaining to the shore and very near shore of ocean or lake)
    estuarine (pertaining to transition from river to ocean settings)
    neritic (pertaining to the seabed in shallow ocean and deep water settings)
    limnetic (pertaining to lakes)
    • Terrestrial refers to land environments (desert, mountain, rivers, etc) - some marine predators live in terrestrial environments.
    Benthic and Pelagic zones
    Figure 14.3. Benthic and pelagic zones.
    Elkhorn Slough, a tidal estuary in central California between Monterey and Santa Cruz Counties
    Figure 14.4. Elkhorn slough, a tidal estuary in central California, has littoral, estuarine, neritic, and limnetic sub environments.

    Feeding behaviors

    * Autotrophic: Produce their own food (primary producers)
    * Heterotrophic: Eat other things (living or dead) (consumers - primary, secondary, and tertiary).
    Feeding strategies of heterotrophic marine organisms:
    * Filter feeding: ex: shellfish
    * Deposit feeding: Eat deposits of dead or decaying matter
    * Carnivorous feeding: Capture and eat it!
    Humpback whales join in on a feeding frenzy.
    Figure 14.5. Humpback whales and birds joining in on a feeding frenzy on smaller fish who were feeding on zooplankton.
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