1. Aquatic Ecology Course Zoo 374

2. 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

3. 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.

4. Importance of zooplankton To Fish

5. 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.
Pennate and centric diatoms
Copepods
A chain of salps near the surface.

6. Again Marine Life Forms Marine Bacteria Plankton Phyto- plankton Zoo-
Nekton
fish &
mammals
Benthos
Benthos&
Macro-algae
Zoo-benthos
Invertebrate
animals
Again

7. Biozone benthic Pelagic littoral supralittoral subtidal Neritic
Oceanic
intertidal
High
medium
low

8. Prof.Dr.Hanan M Mitwally, Marine Biology
plankton
pelagic
Nekton
Benthos
Prof.Dr.Hanan M Mitwally, Marine Biology

9. Ass. Prof.Dr. Hanan M. Mitwally
Biozones
Biological Habitats
Pelagic zone
Benthic zone
Ass. Prof.Dr. Hanan M. Mitwally

10. The word pelagic comes from
the Greek pélagos, = open sea.

11. 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.

12. 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.