aquatic ecology course zoo 374
DESCRIPTION
Zooplankton (Consumersالمستهلكات ) Zooplankton are heterotrophic (sometimes detritivorous) type of plankton. The name of zooplankton is derived from the Greek zoon meaning “animal”. Many zooplankton are too small to be seen individually with the naked eye. Northern krill Jelly fish CopepodsTRANSCRIPT
Aquatic Ecology Course
Zoo 374
• Zooplankton (Consumersالمستهلكات
)• Zooplankton are heterotrophic
(sometimes detritivorous) type of plankton.
• The name of zooplankton is derived from the Greek zoon meaning “animal”.
• Many zooplankton are too small to be seen individually with the naked eye.
Northern krill
Jelly fish
Copepods
Zooplankton are initially the sole prey item for almost all fish larvae.Fish larvae use up their yolk sacs and switch to external feeding for nutrition. Zooplankton limitation can in turn strongly affect the larval survival, and consequently breeding success and stock strength, of fish species.
•Importance of zooplankton To Fish
• Holoplankton Vs Meroplankton
• Holoplankton are those organisms that spend their entire life cycle as part of the plankton (e.g. most algae, copepods, salps, and some jellyfish).
• Meroplankton are those organisms that are only planktonic for part of their lives (usually the larval stage), and then graduate to either the nekton or a benthic (sea floor) existence. Examples of meroplankton include the larvae of sea urchins, starfish, crustaceans, marine worms, and most fish.
A chain of salps near the surface.
Copepods
Pennate and centric diatoms
Again
• Biozone
Pelagic
Neritic Oceanic
benthic
littoral
supralittoralintertidal
subtidal
High medium low
Prof.Dr.Hanan M Mitwally, Marine Biology
plankton
Nekton
Benthos
pelagic
Ass. Prof.Dr. Hanan M. Mitwally
BiozonesBiozonesBiological HabitatsBiological Habitats
Benthic zone
Pelagic zone
Pelagic
NeriticProductive Coastal
Water
OceanicDeep waters of
open ocean
•The word pelagic comes from •the Greek pélagos, = open sea.
• Neritic zone:• It is extending from low tide mark to the edge of the
continental shelf.• Characters of Neritic zone:
• Shallow depth ≈ 200 meters.• well-oxygenated water • Low water pressure.• Stable temperature and salinity levels. • High photosynthetic activities from phytoplankton
and floating sargassum . • At the edge of the neritic zone, the continental shelves
end rapidly descending to the deeper oceanic crust and the pelagic zone.
• Oceanic zone• Any water in the sea that starts
beyond the continental shelves.• offshore, high light levels,
upper regions of water column
• Conditions change with depth: the pressure increases and there is
less light.